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Quality of Life and Dietary Changes among Cancer Patients: a
Systematic Review
Angelos P. Kassianosa*, Monique M. Raatsb, Heather Gagec, Matthew Peacockb
a
Primary Care Unit, Department of Public Health & Primary Care, University of
Cambridge, Cambridge, CB1 8RN
b
School of Psychology, University of Surrey, Guildford, GU2 7XZ, UK
c
School of Economics, University of Surrey, Guildford, GU2 7XZ, UK
* Corresponding author at: Angelos P Kassianos, Primary Care Unit, Department of
Public Health and Primary Care, University of Cambridge, Strangeways Research
Laboratory, Worts Causeway, Cambridge, CB1 8RN, +441223 330323,
[email protected]
1
Abstract
Purpose: To review the literature focusing on the effects of dietary behavioural changes on cancer
patients’ health-related quality of life (HRQOL). Methods: Relevant databases were searched for
studies that report the relationship between dietary changes and HRQOL of people with cancer and
synthesized and systematically reviewed the available evidence. Papers were assessed for
methodological quality and the themes identified were summarized. Results: The selected studies
included only randomized-controlled trials, which target changes in diet. Twelve studies were
identified which focus on the association between lifestyle changes which included changes in diet
and HRQOL among cancer patients. Results have been mixed and dietary changes have been shown
to partly affect HRQOL, but other factors seem to be important as well in defining that relationship.
Moreover cancer groups with higher survival rates (prostate, breast, colorectal) seem to benefit more
from dietary changes while different HRQOL constructs are affected with no clear indication of
directional benefits on physical or mental health. Conclusions: Even though there are some
indications of a direct relationship between dietary changes and HRQOL further research should
establish which areas of HRQOL are directly affected. Perhaps nutritional changes in future
interventions can be isolated in order to identify a potential direct relationship with HRQOL.
Keywords: quality of life; cancer; oncology; diet; lifestyle
2
Introduction
Until recently, very few studies existed that investigated the association between dietary behaviour
and psychosocial factors such as quality of life and physical functioning. Ortega et al. [1] were among
the first to establish an association between diet and physical functioning among people at risk of
cardiovascular disease. Demark-Wahnefried et al. [2] extended this by adding that cancer patients’
physical functioning can be improved with dietary change.
In clinical research, Health Related Quality of Life (HRQOL) is used instead of quality of life and
constitutes patients’ perceptions of their present level of functioning and satisfaction compared to a
perceived ideal one [3]. In general, HRQOL quantifies the psychological, social and physical aspects
of therapy and the illness itself [4]. The importance of targeting HRQOL is evident from the radical
increase of HRQOL-related citations in Pub Med the past two decades [5].
Cancer patients are likely to pursue lifestyle changes and represent a group that could benefit from
dietary interventions [6]. Demark-Wahnefried et al. [7] found a strong interest among cancer patients
in health promotion programmes that encouraged healthier diets. In particular, a review [4] highlights
the importance of nutritional interventions in oncology and the critical importance of the relationship
between HRQOL and changes in diet.
When assessing the relationship between dietary change and HRQOL it is not clear whether diet
affects HRQOL or whether it reflects it. Therefore, systematically investigating the relationship
between changes in diet and HRQOL are prone to showing a potential association. Also, some studies
are limited by using a cross-sectional research design, which does not allow assessment of causal
relationships between HRQOL and changes to cancer patients’ diet [2, 8-9].
Evidence on the association between cancer patients’ HRQOL and their dietary changes are of
prominent interest to health professionals and especially nursing staff. A recent discursive paper [10]
highlighted that current cancer healthcare guidelines suggest that nursing staff should be able to
provide appropriate lifestyle advice including diet. According to the UK Department of Health [11]
guidelines in the UK suggest that educating healthcare staff on the importance and consequences of
changing cancer patients’ diet is an important public health target.
3
Until now, behaviour change strategies are reported to have failed to have an impact on patients’
HRQOL because of research design, poor reported information in reports and the multifaceted
interventions that make it difficult to evaluate the effect of different components [12]. This review
aims to fill the gap in knowledge regarding the association between HRQOL and dietary changes
among cancer patients.
The aims of this review are twofold:
a) To evaluate the relationship between change to diet after cancer and change to HRQOL among
cancer patients and
b) To evaluate the quality of available evidence to inform on gaps in our understanding and propose
directions for future research.
Methods
Search Criteria
Abstracts were initially reviewed using combinations of the following keywords: “cancer”
“survivors”, “quality of life”, “health-related quality of life”, “functioning”, “diet”, “nutrition
intervention”, “well-being”. Limits were set on the search in terms of “English” and “adults” because
there was no opportunity for translating foreign-language papers into English, and potential papers
with children diagnosed with cancer have the potential to skew the homogeneity of participants
because of specifics of child cancer. In Phase 1 the MEDLINE, PSYCINFO and IOS WEB OF
KNOWLEDGE databases were searched for published research articles. Duplicates were checked.
In Phase 2, the focus of reviewing papers was on information regarding the sample (cancer patients),
study design (randomized-control or clinical trials with at least a nutritional aspect on the
intervention), outcome measures (HRQOL), measurement tools (standardized HRQOL tools) and the
testing association (between dietary changes and HRQOL). All papers targeting patients of any cancer
type, in all treatment phases were considered for inclusion to allow for comparisons between cancer
4
and treatment types. Papers with people in cancer survivorship were also considered for inclusion.
Pilot and feasibility studies were excluded because of preliminary data. Abstracts were assessed
against the above criteria and studies that failed to meet the criteria were excluded (Figure 1).
655 studies
found from
search strategy
(databases)
Phase 1: 631 studies
excluded from reading
the abstract
24 studies included for
review given the
inclusion criteria
Phase 2: 12 studies excluded
No data reported (n=1)
Cross-sectional research design (n=4)
Prospective research design (n=2)
Feasibility or pilot studies (n=5)
12 studies eligible for inclusion
Figure 1: Study selection for inclusion in this review
Search Results and Data Synthesis
Initially, 655 studies were identified using the keywords and by hand search, while at Phase 1 631
studies were excluded based on the exclusion criteria of Phase 1. In Phase 2, 24 studies published
between 2000 and 2014, featuring 14,210 individuals diagnosed with cancer, exploring the association
between dietary change and HRQOL were identified. Fourteen studies were randomized-control trials
(RCTs), of which three focus on diet only, eight on diet and exercise, one on exercise, weight
management, diet, alcohol consumption, smoking and acceptance and commitment therapy, one on
diet, exercise and stress management and one on diet, exercise, sedentary behaviour, alcohol
consumption and smoking (see Tables 2-4 for details on interventions used for included studies).
Prospective and cross-sectional studies were excluded (6 studies) and only RCTs were included. That
5
was because RCTs offer robust evidence clearly designating their clinical implications [13] while they
also provide evidence on the direction of relationships and associations. Finally, one study [14] was
excluded because it has not produced any data as yet and four studies because they were pilot or
feasibility studies [15-18]. Therefore after Phase 2, twelve studies published between 2000 and 2014,
including a total of 4,014 individuals diagnosed with cancer, which explored the relationship between
dietary change and HRQOL, were included in the review.
A narrative approach [19] was used to critically and qualitatively reflect on the association between
changes to diet and HRQOL. Analysis focused on study characteristics (publication date; design;
country of origin; participants’ characteristics – both clinical and non-clinical; tool assessment), key
findings, and the conclusions of each study as well as their common findings.
Quality Assessment
A standardized Quality Checklist [20] was used to assess the quality of the included studies. This
checklist was chosen because it draws upon a scoring system based on existing tools and aims at
evaluating the quality of quantitative research papers. It includes 14 assessment criteria (Table 1).
6
Table 1: Criteria used in Quality Checklist [20]
1
Question / objective sufficiently described?
2
Study design evident and appropriate?
3
Method of subject/comparison group selection or source of information/input variables
described and appropriate?
4
Subject (and comparison group, if applicable) characteristics sufficiently described?
5
If interventional and random allocation was possible, was it described?
6
If interventional and blinding of investigators was possible, was it reported?
7
If interventional and blinding of subjects was possible, was it reported?
8
Outcome and (if applicable) exposure measure(s) well defined and robust to measurement /
misclassification bias? Means of assessment reported?
9
Sample size appropriate?
10
Analytic methods described/justified and appropriate?
11
Some estimate of variance is reported for the main results?
12
Controlled for confounding?
13
Results reported in sufficient detail?
14
Conclusions
Each study was scored using a 3-point scale (2= Yes, 1= Partially, 0= No). Where appropriate, a “nonapplicable” score was given to studies where the specific criteria were not relevant. Then adding the
scores and dividing them by the total number of items (excluding those non-applicable), a summary
score was calculated. The score was then converted into a percentage of the maximum possible score.
Two authors (APK, MP) have reviewed the included papers for quality and any discrepancies were
further discussed to come to an agreement.
Results
Study descriptions
Eight studies were conducted in the USA, one in Australia, one in Sweden, one in Portugal, and one
study included participants from the USA, Canada and the UK. Most of the studies included postdiagnosis cancer patients with a range of 6 months-10 years after diagnosis [7, 9, 21-25] while other
7
studies included cancer patients on therapy [26-28] or on active surveillance [29]. All of the studies
included prostate, breast and colorectal cancer patients except two that included endometrial cancer
patients only [22, 24] and one that included colorectal cancer patients only [21]. One study included
other cancer patient groups (head-neck/gastrointestinal tract, prostate, breast, lung, brain, gallbladder
and uterus) as well [26].
All the studies used standardized tools to assess HRQOL. Four studies used the Medical Outcomes
Study Short Form-36 (MOS SF-36) - RAND-36 Health Status Inventory; one study used the Physical
Functioning subscale of MOS SF-36; three studies used the European Organization for Research and
Treatment of Cancer (EORTC) QLQ C-30 and its modules; and four studies used the Functional
Assessment of Cancer Therapy (FACT) tool. Four studies also used the colorectal, breast and prostate
subscale of Functional Assessment of Cancer Therapy (FACT) while another also used SF-36 to
measure functional status and fatigue and endometrial symptoms subscales. This information is
outlined and the studies are presented according to whether they had a diet-only intervention (Table
2), a diet and exercise intervention (Table 3) or a multifaceted intervention (Table 4).
8
Table 2: Included studies with an intervention focused on diet only
Study
Aims
Sample and data
collection
Main and
subsidiary
outcomes
Intervention
HRQOL
measurement
Key findings about
the association of
HRQOL with
dietary changes
Other results
Carmody et
al. (2008)
To
investigate
whether men
with prostate
cancer are
able to make
changes to a
diet that is
strong in
plant-based
foods and
fish and
examine the
effect on
HRQOL and
prostatespecific
antigen
velocity.
36 prostate
cancer patients
and their partners
1) HRQOL
Dietary intervention (11
weeks and 3 months from
baseline)
Theory: unspecified
Intervention strategies:
focused on a plant-based
foods and fish diet
Intervention delivery: 11
weekly 2.5 hours didactic and
experiential classes including
cooked meals compliance,
shopping, study, diet and
mindfulness of dietary
change. The men’s spouses
accompanied them to classes.
Dietary intake (24-hour
Dietary Recall Nutrition
System-NDS-R).
Functional
Assessment of
Chronic Illness
Therapy – Prostate
Cancer Scale (FACTP).
The intervention
group had a
significant increase
in HRQOL (p =. 02)
compared to
controls.
Significant reduction in
the consumption of
saturated fat and
increased consumption of
vegetable proteins with
accompanying reductions
in animal proteins among
those in the intervention
group.
To
investigate
the impact
of a dietary
intervention
on the
HRQOL and
gastrointesti
nal side
effects of
prostate
cancer
patients
130 prostate
cancer patients
who are referred
to local curative
with external
beam
radiotherapy
combined with
either high-doserate
brachytherapy or
proton therapy.
Dietary intervention (intake
of insoluble dietary fibres and
lactose – 2 months)
Theory: unspecified
Intervention strategies:
focused on insoluble dietary
fibres and lactose intake
Intervention delivery:
Standardized dietary advice
(for 24 months after
radiotherapy), delivered by
research dietician on face-to-
EORTC QLQ C-30
and PR25
USA
Pettersson et
al. (2012)
SWEDEN
Received primary
treatment but not
in the last 6
months.
2) Prostatespecific antigen
(PSA) velocity.
1)
Gastrointestinal
side-effects
2) HRQOL
The mean PSA doubling
time for the intervention
group was substantially
longer at the 3-month
follow-up visit than that
of the controls.
No intervention
effect on HRQOL.
Radiotherapy effect on
bowel and urinary
symptoms, fatigue, pain,
physical and role
functioning
No effect of intervention
on reducing
gastrointestinal sideeffects
9
Study
Aims
Sample and data
collection
Main and
subsidiary
outcomes
undergoing
radiotherapy
.
Ravasco,
MonteiroGrillo and
Camillo
(2003)
PORTUGAL
To
investigate
cancer
patients’
HRQOL at
the
beginning
and at the
end of
radiotherapy
(RT); to
investigate
whether
nutrient
intake after
nutritional
counselling
influences
HRQOL and
to see which
symptoms
affect poor
HRQOL and
reduced
nutritional
intake.
Intervention
HRQOL
measurement
Key findings about
the association of
HRQOL with
dietary changes
Other results
EUROQOL and
EORTC (QLQ) –
C30
Individualized
nutritional
counselling improves
HRQOL
Individualized nutritional
counselling improves
nutritional intake.
face sessions.
Dietary intake: Food
Frequency Questionnaire
125 cancer
patients (headneck/gastrointesti
nal tract, prostate,
breast, lung,
brain,
gallbladder,
uterus cancer)
aged 33-86
Participants were
divided into highrisk (headneck/gastrointesti
nal tract), lowrisk (prostate,
breast, lung,
brain,
gallbladder,
uterus) patients.
1) HRQOL
2) Nutritional
status and
nutritional intake.
Diet focused trial assessing
nutritional status
Theory: unspecified
Intervention strategies and
delivery: nutritional
counselling.
Nutritional Status (Ottery’s
Subjective Global
Assessment)
Nutritional Intake (24hr
recall food questionnaire)
Lower risk patients
always had better
HRQOL than highrisk patients (p =.
01).
HRQOL
improvement in
high-risk patients
was correlated with
nutritional intake (p
=. 001) and both
remained stable in
low-risk patients.
Prevalent baseline
malnutrition in HR vs. LR
(p=. 02).
Nutritional intake
associated with
nutritional status (p=
.007) and status did not
change significantly
during radiotherapy.
In therapy
(radiotherapy)
10
Table 3: Included studies with an intervention focused on diet and exercise
Study
Aims
Sample and data
collection
Main and
subsidiary
outcomes
Intervention
HRQOL
measurement
Key findings about
the association of
HRQOL
with
dietary changes
Other results
DemarkWahnefried
et al. (2007)
To test the
efficacy of a
Fresh Start trial
and compare
sequentially
tailored versus
standardized
mail materials on
improving cancer
survivors’ diet
and exercise
behaviour*
543 breast and
prostate cancer
patients (57 ±10.8
years). 519
completed the
follow-up
1) Diet
2) Exercise
Behaviours
3) HRQOL
4) Risk of
depression
5) Social
support
6) Comorbidity
7) Perceived
health
8) Self-efficacy
9) Stage of
readiness for
undertaking
dietary and
exercise change
10) Tobacco use
11) Weight
Status
Diet and exercise focused trial
called FRESH START aiming at
improving fruit and vegetable
consumption, reducing fat intake
and increasing exercise –
baseline and 10 months followup
Theory: Social Cognitive
Theory [30] and Transtheoretical
Theory [31]
Intervention strategies: 10month programme of tailored
mailed print materials or 10month programme of nontailored mailed materials.
Intervention delivery: 1
telephone survey at baseline and
1 year afterwards assessing
BMI, dietary consumption,
physical activity and
psychosocial/behavioural
variables.
Dietary intake (Diet History
Questionnaire, eating 5 or more
servings of fruits and vegetables
and eating a low-fat diet only at
baseline, weight status)
Functional
Assessment of
Cancer Therapy
FACT- B
No improvements
were observed in
HRQOL by either
positive dietary or
exercise changes on
follow-up.
Both arms of the
intervention improved
their lifestyle
behaviours (P<.05).
USA
*there are
indications of
these behaviours’
effect on
HRQOL
Early staged
patients with in
situ, localized or
regional cancer
within 9 months
of diagnosis
Significantly greater
gains occurred in the
Fresh Start intervention
versus the control arm
(on practice of two or
more goal behaviours,
exercise minutes per
week, F&V per day,
total fat, saturated fat
and BMI).
11
Study
Aims
Sample and data
collection
Main and
subsidiary
outcomes
Intervention
HRQOL
measurement
Key findings about
the association of
HRQOL
with
dietary changes
Other results
DemarkWahnefried
et al. (2008)
To test the
feasibility and
variability of a
home-based
intervention trial
to prevent weight
gain and
concurrent losses
in muscle mass.
90 premenopausal
breast cancer
patients.25-53
years old
Newly diagnosed
stage I-IIIA and
on adjuvant
chemotherapy
1) Physical
Activity
2) Diet
3) Body
Composition
4) Body Density
5) Serologic
Biomarkers
6) Quality of
Life, Anxiety
and Depression.
7) Feasibility
Diet focused trial called
Survivor Training for Enhancing
Total Health (STRENGTH) –
baseline and 6 months follow-up
Theory: Social Cognitive
Theory [30] (verbal and written
instructions)
Intervention strategies: 3
intervention trials: one attention
control group with a calciumrich diet (CA) intervention and
two experimental arms: one with
CA and exercise (EX) and one
with CA, EX and high fruit and
vegetable and low-fat diet
(FVLF) arm.
Intervention delivery:
telephone counselling with 14
contacts of 10-30 minutes –
weekly during the first month
and bi-weekly for the remaining
5 months
Dietary intake (Diet History
Questionnaire and maintenance
of high fruit and vegetable and
low-fat diet during the
intervention)
Functional
Assessment of
Cancer Therapy
FACT- B
Significant
improvements to
HRQOL on all
groups of the
intervention
including the FVLF
group
Modest attrition
observed (8.8%).
Diet and exercise intervention
programme called SUCCEED –
baseline, 3 and 6 months followup.
Theory: Social Cognitive
Theory [30]
Intervention Strategies:
randomized to two groups:
FACT-G
USA
McCarroll et
al. (2013)
USA
To investigate
whether a diet
and exercise
intervention can
have an impact
on self-efficacy
and HRQOL of
obese/overweigh
75 overweight
and obese early
stage endometrial
cancer survivors.
1) Self-efficacy
2) HRQOL
Also the Hospital
Anxiety and
Depression Scale
(HADS)
No significant
differences on
anxiety and
depression scales.
Increased calcium
intake in all arms and
higher F&V intake and
lower fat intake in the
CA+EX+FVLF arm.
No differences in
physical activity.
Significant difference
in the percentage of
body fat.
No differences
observed in other end
points.
Improved fatigue 3
months after the
intervention.
Enhanced self-efficacy.
Improved physical
functioning 6months after the
12
Study
Aims
Sample and data
collection
Main and
subsidiary
outcomes
t endometrial
cancer patients.
Mosher et al.
(2009)
USA,
CANADA,
UK
To investigate
the association
between healthy
behaviours and
quality of life
outcomes.
To investigate
whether
adherence to a
healthy lifestyle
behaviour
HRQOL
measurement
intervention (SUCCEED) on a
6-month intervention and in
usual care.
Intervention delivery: delivered
by physicians and nutritionrelated health professionals.
Randomization based on
baseline BMI calculations, 10
60-minute weekly sessions
followed by 6 bi-weekly ones
(goal setting and individual
counselling embedded).
Dietary intake: BMI reductions.
753 older (≥65
years) long-term
breast, prostate
and colorectal
cancer survivors
1) HRQOL
Long-term
survivors (≥ 5
years postdiagnosis).
DemarkWahnefried
et al. (2006)
Intervention
420 older prostate
and breast cancer
patients (≥65
years)
1) Declines in
physical
functioning (PF)
Key findings about
the association of
HRQOL
with
dietary changes
Other results
intervention.
Diet and exercise focused trial
called Reach Out to Enhance
Wellness (RENEW)
Theory: unspecified
Intervention strategies: homebased diet and exercise
Intervention delivery: 2
telephone surveys before the
intervention, which included
tailored-mailed materials and
telephone counselling.
Dietary intake (2 24-hour
dietary recall interview using the
Nutrition Data System Software)
BMI (self-reports)
MOS SF-36 – 8
domains.
Diet and exercise focused trial
(6 and 12 months from baseline)
called Leading the Way in
Exercise and Diet (LEAD)
MOS SF-36
Physical
Functioning
Subscale with
four items from
Diet quality
significantly
associated with
physical
functionality and
vitality.
There is high
prevalence of
suboptimal health
behaviours among
older long-term
survivors.
Indications of a
negative impact of
obesity and positive
impact of physical
activity and healthy
diet in physical
HRQOL.
Differences between
intervention group
and controls were
clinically but not
statistically
The intervention after 6
months is associated
with statistically
significant
improvements in diet
13
Study
Aims
USA
intervention may
prevent
functional
decline.
Sample and data
collection
Within 18 months
of diagnosis
(therapy stage:
unknown)
Main and
subsidiary
outcomes
Intervention
HRQOL
measurement
Key findings about
the association of
HRQOL
with
dietary changes
Other results
2) Physical
Activity
Theory: unspecified
Intervention strategies: aimed
to increase exercise and improve
diet (increasing fruits and
vegetables and whole grains
consumption, decrease total fat;
cholesterol and saturated fat and
adequate calcium and iron)
Diet Quality (Diet Quality
Index from 3-day dietary recalls
– Nutrition Data System
Software – NDS, Minneapolis)
Satariano et al.
[32]
significant.
quality (p <. 003) but
non-significant changes
in other domains.
3) Diet quality
Intervention
improved both
HRQOL and
depression.
Recidivism was not
significant (all p<. 05)
from 6 to 12 months.
Significant
improvements in selfefficacy for exercise
but no changes were
observed in readiness
to exercise measures.
Emotional well-being
and self-efficacy are
improved with weighloss
Von
Gruenigen et
al., (2009)
USA
To assess the
effects of a
lifestyle
intervention in
overweight and
obese
endometrial
cancer survivors’
HRQOL,
depression, selfefficacy and
eating behaviour
changes.
45 early stage
endometrial
cancer survivors
of unknown age.
1) HRQOL
Unknown if in
treatment but
with stage I-II
endometrial
cancer.
3) Self-efficacy
2) Depression
4) Eating
behaviour
changes.
Diet and exercise focused
intervention (6 months from
baseline)
Theory: Social Cognitive
Theory [30]
Interventions strategies:
aiming at nutrition and exercise
Intervention delivery:
conducted by a registered
dietician (contracting
participants), the primary
investigator (met with
participants at 3, 6 and 12
months) and a psychologist
Functional
Assessment of
Cancer TherapyGeneral FACT –
G with fatigue
and endometrial
symptoms
subscales and
MOS SF-36 for
functional status.
Intervention did not
have effects on
global HRQOL
outcomes but
significant
differences observed
for emotional
wellbeing HRQOL
(p=. 02)
Significant
improvements for selfefficacy related to
social pressure (p =.
03) and restraint (p =.
02) and significant
differences for selfefficacy related to
negative emotions (p <.
01), food availability (p
=. 03) and physical
discomfort (p =. 01).
14
Study
Aims
Sample and data
collection
Main and
subsidiary
outcomes
Intervention
HRQOL
measurement
Key findings about
the association of
HRQOL
with
dietary changes
Other results
MOS
SF-36
Physical
functioning
Subscale)
Overall
HRQOL
decreased after the
intervention
but
were
of
lower
magnitude compared
to the control group
and were sustained
for
overall
and
mental health. (2.15; 95%CI, -0.36
to -3.93 vs. -4.84;
95% CI, -3.04 to 6.63) and with p =.
03.
The mean baseline
lower
extremity
function were 78.2 and
changes were 0.34
(95% CI, -0.84 to 1.52)
in intervention group
compared with control
-1.89 (95% CI, -0.70 to
-3.09) with p=0.005.
(conducted cognitive and
behavioural self-management
strategies for stress management
and weight-loss).
Eating Behaviour (ThreeFactor Eating Questionnaire
TFEQ)
Patient anthropometric data
(i.e. weight, BMI, measured
manually by a clinician).
Morey et al.
(2009)
USA
To
investigate
the effect of a
diet and exercise
intervention in
older overweight
cancer survivors’
functional
decline
641 overweight
(BMI ≥25 and
<40)
–
319
intervention
participants and
322
controls
(aged
65-91)
prostate, breast
and
colorectal
cancer patients
Long-term cancer
survivors (≥ 5
years
after
diagnosis)
1)
Physical
Functioning
(primary)
2) Changes in
function
on
basic
and
advanced lower
extremity
function
subscales
of
Late
Life
Function
and
Disability Index
3)
Physical
Activity
4) BMI
5)
Overall
HRQOL
Diet and exercise focused trial
called Reach Out to Enhance
Wellness (RENEW) (12 months
from baseline)
Theory:
Social
Cognitive
Theory [30]
Intervention strategies: homebased intervention to promote
exercise, improving diet quality
and modest weight-loss
Intervention
delivery:
a
program
of
telephone
counselling
and
automated
prompts (15 sessions and 8
prompts), a personally tailored
workbook and a series of
newsletters.
Changes in function (basic and
advanced
lower
extremity
function subscales of Late Life
Function and Disability Index)
Dietary intake (2 24-hour
recalls - Nutrition Data System
Software)
Physical functioning
declined
postintervention
(p
=0.03).
Physical
functioning, general
health and social
functioning
were
significantly
changed.
Physical activity and
dietary
behaviours
increased significantly
in the intervention
group compared with
the
control
while
weight loss was greater
(2.06 kg – 95& CI,
1.69 to 2.43 kg) vs.
95% CI, 0.51 to 1.33
kg respectively with p
<. 001.
15
Table 4: Included studies with a multifaceted intervention
Study
Aims
Sample
and
data collection
Main
subsidiary
outcomes
Daubenmenier
et al. (2006)
To investigate
the effects of
lifestyle changes
on prostate
cancer patients’
HRQOL,
perceived stress
and self-reported
sexual function.
93
prostate
cancer patients
(44 intervention,
49
usual-care
controls)
1) Health-related
Quality of Life
USA
Participating in
active
surveillance
and
2) Perceived
Stress
3) Self-reported
sexual function
Intervention
HRQOL
measurement
Key findings about the
association of HRQOL
with dietary changes
Other results
Diet, exercise and stress
management focused trial
(12 months from baseline)
MOS SF-36
Significant correlations
between
lifestyle
changes and specific
areas of HRQOL – the
physical
health
summary score (role
limitations
due
to
physical
symptoms,
vitality,
social
functioning,
role
limitations
due
to
emotional symptoms,
mental
health
and
bodily pain) r = .21 (p <
.05) to r = .32 (p < .01).
No
significant
associations
between
lifestyle changes and
mental health summary
score and sexual function.
Theory: unspecified
Intervention strategies: a
low-fat, vegan diet, enhanced
exercise
and
stress
management
Intervention
delivery:
delivery of a diet, 3-hours perweek moderate exercise, and
1 hour of daily stress
management practice. Also
weekly
support
group
meetings
were
held
throughout.
Lifestyle behaviors (lifestyle
index)
Changes in lifestyle
index not related to
changes
in
the
individual
SF-36
subscales
among
intervention participants
and across experimental
groups but changes over
time showed enhanced
physical HRQOL.
Healthier lifestyle at entry
associated with greater
physical and mental
health
and
sexual
functioning
Changes in lifestyle index
not related to changes in
sexual function.
Participants
whose
lifestyle improved over
time showed decreased
perceived stress.
16
Study
Aims
Sample
and
data collection
Main
subsidiary
outcomes
Hawkes et al.
(2014)
To investigate
the effect of a
multiple health
behaviour
change
programme (Can
Change)
targeting
colorectal cancer
survivors
410
primary
colorectal cancer
survivors,
1) Physical
activity
2) HRQOL
3) Cancer-related
fatigue
4) Behavioural
and psychosocial
outcomes
AUSTRALIA
and
Intervention
HRQOL
measurement
Key findings about the
association of HRQOL
with dietary changes
Other results
General
lifestyle
intervention (6 weeks from
baseline)
called
“CanChange”:
Theory: Social Cognitive
Theory [30] including
psychosocial and lifestyle
support aiming at positive
lifestyle
behaviour
changes.
Interventions strategies:
included healthy eating
and dietary goals and were
based
on
national
guidelines
for
the
prevention of colorectal
cancer.
Intervention delivery: by
telephone sessions while
participants received a
handbook for goal setting
and personal assessment –
11 sessions based on
acceptance
and
commitment
therapy
focusing
on
physical
activity,
weight
management, diet, alcohol,
smoking.
FACT-C
Physical
functioning
improved 6 (p = .049)
and 12 months (p =
.037) after intervention.
Post-traumatic
growth
improved at 6-12 months,
spirituality
and
acceptance at 6 months
after the intervention.
17
Themes identified
Association between HRQOL and dietary change
Only three studies [25-26, 28] used an intervention focusing on diet only. Six studies [9, 22-24, 33]
used a combined intervention focusing on diet and exercise, one study [29] used a combination of
diet, exercise and stress management and one study [21] used a general lifestyle intervention which
included healthy eating.
Four studies [7, 24-25, 28] showed a non-significant relationship between dietary changes and
HRQOL while seven studies [9, 21-22, 26-27, 29, 33] found significant results either for the
relationship between dietary changes and HRQOL or with some aspects of HRQOL (physical
functioning) and dietary changes. Even though one study [23] found clinically significant effects of a
home-based diet (aiming at healthier diet) on HRQOL they were unable to demonstrate that this
association was statistically significant. The relationship between dietary change and change in
HRQOL is found to be in the following direction: dietary change (factor) – HRQOL (outcome).
Carmody et al. [25] found a significant increase on prostate cancer patients’ HRQOL (p= .02) after
having healthier diets with an improvement in diet quality showing a positive association with
increased HRQOL.
Some researchers found that interventions to improve diet quality did indeed improve psychosocial
well-being/depression and HRQOL [23] and overall HRQOL [26, 29, 33]. Another study using the 5A-Day fruit and vegetable recommendation found that the interventions did not significantly affect or
lead to a change in HRQOL but found weight loss (which possibly indicates a change in eating habits)
to improve emotional well-being and self-efficacy [24].
All of the standardized HRQOL tools comprise measures of mental and physical health. Not all
studies have reported significant changes in both domains. For example, two studies [9,21] found diet
change to have a positive effect on physical HRQOL outcomes only. On the other hand, Daubenmeier
et al [29] found significant improvements to six HRQOL subscales (role limitations due to the
physical symptoms, vitality, social functioning, role limitations due to emotional symptoms, mental
18
health and bodily pain) but not on physical functioning and general health. Furthermore different
subscales of HRQOL are differently associated with dietary changes. Three studies found significant
differences in physical functioning for all patients [9, 23, 33] and one only for head and neck cancer
patients [26]. Two studies found significant differences in social functioning [29-30], two in vitality
[9, 29], one in general health [33] and one in bodily pain, role-emotional, role functioning and mental
health [9]. McCarroll et al. [22] found the diet and exercise intervention to improve physical HRQOL
six months after and fatigue three months after the intervention.
Cancer Type
One study [7] including breast cancer patients found significant improvements to HRQOL in all
groups of the intervention. Specifically, components with a) a selenium-rich diet with exercise and b)
a selenium-rich diet with exercise and a diet high in fruit and vegetables and lower in fat led to
improved HRQOL, but no significant improvements were found with regard to anxiety and
depression. At the same time, dietary changes were found to be associated with changes on 3 out of 4
mental health subscales: social functioning (p = .05), role limitations-emotional (p = .02), mental
health (p = .01) and 2 out of 4 physical health subscales: physical functioning (p = .02) and bodily
pain (p = .03). Two studies, which included prostate cancer patients, found an association between
HRQOL and changes in diet. The one found a significant increase of HRQOL (p = .002) after
adhering to a healthier diet and an association between a healthier lifestyle and physical, mental health
and sexual functioning [27] while the other found improvements to lifestyle associated with
improvements to physical health and perceived stress [31]. The third study that included prostate
cancer patients [30] and employed a dietary intervention only did not find the intervention to improve
HRQOL but found radiotherapy to increase prostate-specific symptoms (urinary and bowel), pain,
fatigue, physical and role functioning.
Two studies [7, 25], which included both prostate and breast cancer patients, found that changes to
physical functioning were clinically significant but not statistically significant. One found that
19
HRQOL and depression scales were improved [25]. The other study [7] found no significant
improvement to HRQOL (p = .16).
One study that included colorectal cancer patients found an improvement in physical health six and
twelve months after an intervention based on elements of the acceptance and commitment therapy
which included diet [21] A study that included prostate, breast and colorectal cancer patients found a
decrease in physical functioning (p = .03), an increase in overall HRQOL (p < .001) and changes to
social functioning and general health (p = .02) [33]. A healthier diet was found to be associated with
increased physical health (vitality and physical functioning) (p < .05) and lower a BMI associated
with reduced physical health (p < .001). Two studies with endometrial cancer patients found a
significant increase in overall HRQOL (p = .02) [24] and improvement of fatigue (p = .008) and
physical health (p = .048) [22].
Finally, one study [26] included patients with head-neck and gastrointestinal tract (high-risk group)
and prostate, breast, lung, brain, bladder and uterus cancer (low-risk group) and found an
improvement to HRQOL after nutritional counselling in both groups but higher in high-risk patients
than low-risk patients (p = .001). Also, at the end of radiotherapy, HRQOL was found to improve
through dietary change in high-risk patients (p = .001). This study is the only one that indicates the
differences in how dietary changes affect HRQOL according to cancer type with high-risk patients
having higher improvement onto their HRQOL than the low-risk group.
Stage of treatment
It appears that results from studies using interventions focused on cancer patients at an early stage
after diagnosis and while undergoing treatment [7, 23-24, 26-28] have mixed results. This is clearer in
one study [28], which showed the dietary intervention not to improve HRQOL but radiotherapy to
decrease HRQOL by increasing prostate-specific symptoms, pain, fatigue, physical, and role
functioning. On the other hand, studies with participants who were cancer survivors and with most of
them already having undergone treatment (surgery, radiotherapy, chemotherapy) more than two years
20
before or who were on active surveillance found a significant association between dietary change and
HRQOL [9, 21-22, 25, 29, 33].
Quality appraisal
The overall quality of studies can be rated as very high. Ten out of twelve studies scored higher than
90% with only two scoring less. Ratings ranged from 79.2% to 95.8 % (Mean = 91.7, SD = 2.4). All
of the studies succeeded well in having a question or objective sufficiently described an evident and
appropriate study design, a recruitment method and source appropriate and described, sufficiently
described subject characteristics, appropriate and described analytic methods, variance estimations,
detailed reported results, and a conclusion supported by results. Studies were less successful in having
well-defined outcome and exposure measures that were robust to measurement bias, and having
clearly described randomization procedures. There was limited information on sample size
calculations and this is discussed in detail later in the limitations of the included studies. All studies
were only partly successful at controlling for confounding variables (Table 5).
21
Table 5: Quality appraisal of included studies in the systematic review
Study
Question
or
objective
sufficiently
described
Study
design
evident and
appropriate
Method of
subject/comparison
group selection or
source of
information/input
variables described
and appropriate?
Subject (and
comparison
group, if
applicable)
characteristics
sufficiently
described?
If
interventional
and random
allocation
was possible,
was it
described?
If
interventional
and blinding of
investigators
was possible,
was it
reported?
If
interventional
and blinding
of subjects
was possible,
was it
reported?
Carmody et al (2008)
2
2
2
2
1
NA
NA
Demark-Wahnefried et al (2006)
2
2
2
2
2
NA
NA
Demark-Wahnefried et al (2007)
2
2
2
2
2
NA
2
Demark-Wahnefried et al (2008)
2
2
2
2
2
NA
NA
Daubenmeier et al (2006)
2
2
2
2
2
NA
NA
Hawkes et al (2014)
2
2
2
2
2
NA
NA
McCarroll et al (2013)
2
2
2
2
2
NA
NA
Morey et al (2009)
2
2
2
2
2
NA
NA
Mosher et al (2009)
2
2
2
2
1
NA
NA
Pettersson et al (2012)
2
2
2
2
2
NA
NA
Ravasco et al (2003)
2
2
2
2
2
NA
NA
Von Gruenigen et al (2009)
2
2
2
2
2
NA
NA
Total
26/26
26/26
25/26
26/26
24/26
-
2
22
Table 5: Quality appraisal for included studies in the systematic review (continued)
Study
Outcome and
exposure
measures well
defined and
robust to
measurement
bias? Means of
assessment
reported?
Was a
sample size
calculation
reported?
Analytic
methods
described/just
ified and
appropriate?
(e.g., testing
of parametric
assumptions)
Some
estimate of
variance is
reported for
the main
results?
Controlled
for
confounding?
Results
reported
in
sufficient
detail?
Conclusion
supported
by results?
Overall
% of
available
score for
all item
checklists
Carmody et al (2008)
1
0
2
2
1
2
2
79.2
Demark-Wahnefried et al (2006)
1
2
2
2
1
2
2
91.7
Demark-Wahnefried et al (2007)
1
2
2
2
1
2
2
92.3
Demark-Wahnefried et al (2008)
2
2
2
2
1
2
2
95.8
Daubenmeier et al (2006)
1
0
2
2
1
2
2
91.7
Hawkes et al (2014)
2
2
2
2
1
2
2
95.8
McCarroll et al (2013)
2
0
2
2
1
2
2
87.5
Morey et al (2009)
2
2
2
2
1
2
2
95.8
Mosher et al (2009)
2
2
2
2
1
2
2
91.7
Pettersson et al (2012)
2
2
2
2
1
2
2
95.8
Ravasco et al (2003)
1
1
2
2
1
2
2
90.9
Von Gruenigen et al (2009)
1
2
2
2
1
2
2
91.7
20/26
19/26
26/26
26/26
13/26
26/26
26/26
Total
23
Limitations of included studies
The included studies have several limitations that influence their internal and external validity and limit
the generalizability of their findings. The use of self-report tools to measure HRQOL is not really a
limitation even though it is reported as such by some of the authors of the included studies. In cancer
research, most of the information used to measure HRQOL is collected using self-report
questionnaires. Moreover, Osoba [34] indicate that quality of life measures are more appropriately
assessed using questionnaires even though self-report assessment has minimum objectivity. However,
three authors state this as a study limitation [9, 27, 33]. Self-report methods for measuring HRQOL
continue to be widely used and are regarded as an accepted means of measurement so it is not a major
barrier for measuring HRQOL.
A low response rate leading to response bias is another limitation common to most of the included
studies. Two studies explicitly state this as a limitation of their study with a response rate of 34% [23]
and 6% [9] while a third [7] indicate differential dropout between the study arms as a limitation (6.6% intervention arm and 2.2% - attention control arm). Moreover Mosher et al. [9] found significant
differences between respondents and non-respondents with respect to sex, age, race and time since
diagnosis. The rest of the included studies failed to report response rates.
Also, not all the studies reported sample size calculations and some even had a small number of
participants. This has affected the quality of reporting of relationships given the limited variance in diet
and HRQOL seen with such a small sample. One study [21] had limited intervention satisfaction data
available.
Finally it was not possible to determine whether the source of change in HRQOL is the healthier diet or
the behavioural change itself. The mechanisms of behavioural change are important for an
understanding of why some patients change their behaviour while others do not. An association is
evident in some studies rather than a causal explanation.
24
Discussion
The aim of this review was to evaluate the relationship between change in diet after cancer and change
in HRQOL and to evaluate the quality of available evidence. The findings have been mixed. Twelve
studies were identified with a range of cancer type patients, using standardized tools to measure
HRQOL and interventions that targeted dietary change. Eight of the included studies found significant
differences between changes in diet and changes in HRQOL while four did not. Results have been
mixed for the domains of HRQOL affected by dietary changes. In general, findings per cancer type
varied but it was found that studies that included prostate, breast and colorectal cancer patients found
significant associations between HRQOL and dietary change. Findings per stage of treatment also
varied. The quality appraisal of included studies revealed highly rated quality.
The mixed findings from this systematic review reflect contrary findings found previously on two
prospective studies. One [35] included head and neck (group a) or oesophageal cancer patients (group
b) that were evaluated one and three weeks after hospital discharge and used as their own controls and
found a non-significant relationship between dietary changes and HRQOL. On the contrary, Wayne et
al., [36] included breast cancer patients evaluated 2 years after study entry and found a significant
relationship between diet and HRQOL, which was stronger for mental rather than physical functioning.
This strengthens the argument in this review that survivors rather than persons in active treatment can
more adequately enhance their HRQOL through dietary changes. For example recent evidence show
that cancer therapy [37] or surgery [38] can have a severe impact on patients’ HRQOL.
A meta-analysis of physical activity interventions [39] and a review of physical activity primary care
interventions [40] point out that single-factor intervention are more effective in achieving lifestyle
change-related outcomes rather than multiple-factor interventions. Unlike these findings, this
systematic review could not support this. There was no consistent evidence that studies including a
single-factor intervention (i.e. interventions with a dietary component only) were associated with
HRQOL-related benefits compared to studies including a multifaceted intervention.
25
Only one study [29] found dietary change to affect mental health, contrary to Wayne et al. [36] who, in
their prospective study, had previously found better diet quality to be associated with three of the four
mental health subcategories and two out of four physical health subcategories and diet quality to be
associated with mental and physical functioning. Recent evidence proposed that fatigue is the most
impacted component among breast, prostate and colorectal cancer patients [41]. This review found
different components of HRQOL to be affected by interventions with a dietary component.
Cancer patient groups in the included studies were affected differently by changes to their diet. This is
in line with Blanchard et al., [42] who found that healthy eating recommendations significantly
affected the HRQOL of breast, prostate and colorectal and skin melanoma patients but not of bladder
and uterine cancer patients. Previously, it was demonstrated that a significant relationship between
physical well-being and diet among cervical cancer patients while breast cancer patients had a
significant improvement to their physical well-being and exercise but not to their diet [43]. This may
indicate the importance, when assessing cancer survivors rather than cancer patients who are in
treatment, of noting that the treatment can have adverse side effects, which can interfere with their
HRQOL.
Overall cancer populations with a high percentage of survivors (breast, prostate and colorectal) seem to
be most responsive to interventions, judging by the indications of dietary modification effects on their
HRQOL. This may be due to the fact that they are the most researched population but it can also reflect
gender issues with female patients more interested in changing their diets or even media coverage of
dietary effects. There are also concerns with external validity that make generalizing the findings of
these studies problematic, namely that the majority of them deal with the most frequently researched
cancer populations.
Differences between cancer types were also found in a study looking at changes to head and neck
cancer patients’ relationship with food [44]. This is similar to what Ravasco et al. [26] found with the
high-risk group of cancer patients (head and neck) having less improvement in their HRQOL after the
intervention rather than low-risk group. It is expected that head and neck cancer patients would report
differently as the cancer has a direct influence on their capacity to eat. However, if patients’
perspectives and attitudes towards food differ among cancer groups, this may explain the wide variance
26
in results when it comes to eating behaviour, especially among cancer groups receiving different and
diverse therapies.
Methodological issues can also explain the variability of findings such as the fact that two of the five
included studies that found non-significant associations between HRQOL and dietary change, suffer
from small sample size. There is also a chance of ceiling effects because scores on HRQOL were
already high at baseline.
Identifying any associations between any form of lifestyle change and HRQOL is vital as it can help
health practitioners and policy makers decide whether modifications to a cancer patients’ lifestyle will
be beneficial or not. The literature provides useful indications that an association may be present but
suggests that more research is needed to identify how different forms of HRQOL are affected by
lifestyle changes and, moreover, to focus on dietary change in particular. More work in this area is
clearly needed as previous research [45] indicates that physicians’ recommendations can lead to
significant positive dietary change among patients. This review offers useful information to begin the
understanding of the relationship between HRQOL and dietary changes in the cancer population.
Limitations
A problem derives from the fact that very few studies in the review include diet as the single target of
the intervention. Most of them include other changes as well, like exercise, smoking cessation, etc. The
issue of multi-behavioural interventions creates a difficulty in isolating the effects of dietary change
from those of other lifestyle changes.
Another problem is that the included patients were at different treatment stages. Intervening with a
group of cancer patients who are undergoing active treatment is different from intervening with cancer
survivors while the time since diagnosis also plays an important role in the type and efficacy of the
intervention. Side-effects on patients in active treatment can substantially influence their HRQOL
through effects on their eating capacity (swallow, appetite), bowel function, treatment-related anxiety,
etc. For example, two randomized control trials [46-47] share a lot of similarities but differ
significantly due to the fact that one had patients on active treatment and the other did not. Demark-
27
Wahnefried [7] suggests that the timing of lifestyle intervention is important when HRQOL is the
primary outcome. However, most of the included studies did not have HRQOL as the primary
outcome.
The variance in results on HRQOL domains confirms the need for robustly designed RCTs that aim to
investigate the effects of lifestyle changes on HRQOL and the necessity to re-visit the properties of
HRQOL psychometric testing. It could be that relating HRQOL with other mental and physical health
variables such as self-efficacy and control or depression, sleep quality and anxiety levels may highlight
the overlap of HRQOL with other psychological constructs and explain mixed results. Nonetheless, the
variability in results can be moderated by the inclusion of a perceived behavioural control measure in
future studies. The importance of control is one that might interlink with other constructs like HRQOL.
Future studies should aim to identify whether there is an underlying dimension linking HRQOL and an
internal sense of control and investigate whether changes to lifestyle or behaviour affect either or both
of these constructs. Future systematic reviews can consider including patients in active treatment or
active surveillance only.
Conclusions
Findings from the systematic review are inconclusive but indicative of the need to further investigate
the association between dietary changes and HRQOL among cancer patients. Firstly, it is suggested
that the interventions used to change patients’ dietary behaviour have mixed effects on patients’
HRQOL. Secondly, different constructs of HRQOL are differently affected by changes in diet with no
clear indication of a strong effect on physical or mental health. Therefore there is need to explore the
areas of patients’ HRQOL that are associated with dietary behaviour change. Thirdly, patients
diagnosed with a cancer with high survival rates (prostate, breast and colorectal cancer) or those
categorized as lower risk are more likely to experience changes in their HRQOL after changing their
diet compared to other cancer types. Therefore, cancer survival rates create the need to understand the
association between HRQOL and dietary behaviour change. This can trigger clinicians to focus on
patients’ adherence to healthy eating recommendations.
28
References
1. Ortega, R.M., Rodríguez L., Andrés, P., Gaspar, M.J., Robles, F., Jiménez, A., Pascual, T. (1996).
Functional and psychic deterioration in elderly people may be aggravated by folate deficiency. Journal
of Nutrition 126, 1992–1999.
2. Demark-Wahnefried, W., Clipp, E.C., Morey, M.C., Pieper, C.F., Sloane, R., Clutter Snyder, D.,
Cohen, H.J. (2004). Physical function and association with diet and exercise: Results of a crosssectional survey among elders with breast or prostate cancer. International Journal of Behavioural
Nutrition and Physical Activity, 1(16).
3. Ferrell, B.R., Dow, K.H. & Grant, M. (1996). Measurement of quality of life in cancer survivors.
Quality of Life Research, 4, 523-531.
4. Marin Caro, M.M., Laviano, A. & Pichard, C. (2007). Nutritional intervention and quality of life in
adult oncology patients. Clinical Nutrition, 26, 289-301.
5. Armstrong, D., Liford, R., Ogden, J., Wessely, S. (2007). Health-related quality of life and the
transformation of symptoms. Sociology of Health and Illness, 29(4), 570-583.
6. Patterson, R.E., Neuhouser, M.L., Hedderson, M.M, Schwartz, S.M., Standish, L.J., Bowen, D.J.
(2003). Changes in diet, physical activity, and supplement use among adults diagnosed with cancer.
Journal of the American Dietetic Association, 103, 323-328.
7. Demark-Wahnefried, W. (2007). Move onward, press forward, and take a deep breath: can lifestyle
interventions improve the Quality of Life of women with breast cancer, and how can we be sure,
Journal of Clinical Oncology, 25(28).
8. Blanchard, C.M., Stein, K.D., Baker, F., Dent, M.F., Denniston, M.M., Courneya, K.S., Nehl, E.
(2004). Association between current lifestyle behaviours and health-related quality of life in breast,
colorectal and prostate cancer survivors’, Psychology & Health, 19(1), 1-13.
9. Mosher, C.E., Sloane, R., Morey, M.C., Clutter Snyder, D., Cohen, H.J., Miller, P.E., DemarkWahnefried. (2009). Associations between lifestyle factors and Quality of Life among older long-term
breast, prostate, and colorectal cancer survivors. Cancer, 115, 4001-4009.
10. Murphy, J.L. and Girot, E.A. (2013). The importance of nutrition, diet and lifestyle advice for
cancer survivors- the role of nursing staff and interprofessional workers. Journal of Clinical Nursing,
22, 1539-1549.
29
11. Department of Health. (2010). Equity and excellence: Liberating the NHS. Available at:
http://www.dh.gov.uk/prod_consum_dh/groups/dh_digitalassets/@dh/@en/@ps/documents/digitalasset
/dh_117794.pdf (Accessed 29 July 2014).
12. Michie, S. and Abraham, C. (2004). Interventions to change health behaviours: Evidence-based or
evidence-inspired? Psychology and Health, 19(1), 29-49.
13. Cockle-Hearne, J., Faithful, S. (2010). Self-management for men surviving prostate cancer: a
review of behavioural and psychosocial interventions to understand what strategies can work, for
whom and in what circumstances. Psycho-Oncology, 19(9), 909-22.
14. Haseen, F., Murray, L.J., O’Neill, R.F., O’Sullivan, J.M., Cantwell., M.M. (2010). A randomized
control trial to evaluate the efficacy of a 6 month dietary and physical activity intervention for prostate
cancer patients receiving androgen deprivation therapy. Trials, 11, 86.
15. Bourke, L., Thompson, G., Gibson, D. J., Daley, A., Crank, H., Adam, I., ... & Saxton, J. (2011).
Pragmatic lifestyle intervention in patients recovering from colon cancer: a randomized controlled pilot
study. Archives of physical medicine and rehabilitation, 92(5), 749-755.
16. Hawkes, A. L., Patrao, T. A., Green, A., & Aitken, J. F. (2012). CanPrevent: a telephone-delivered
intervention to reduce multiple behavioural risk factors for colorectal cancer. BMC Cancer, 12(1), 560.
17. Schmidt, M., Pfetzer, N., Schwab, M., Strauss, I., & Kämmerer, U. (2011). Effects of a ketogenic
diet on the quality of life in 16 patients with advanced cancer: A pilot trial. Nutr Metab (Lond), 8(1),
54.
18. Von Gruenigen, V. E., Frasure, H. E., Kavanagh, M. B., Lerner, E., Waggoner, S. E., & Courneya,
K. S. (2011). Feasibility of a lifestyle intervention for ovarian cancer patients receiving adjuvant
chemotherapy. Gynecologic oncology, 122(2), 328-333.
19. Petticrew, M., & Roberts, H. (2008). Systematic reviews in the social sciences: A practical guide.
Wiley.
20. Kmet, L., Lee, R., & Cook, L. (2004). Standard quality assessment criteria for evaluating primary
research papers from a variety of fields. Alberta Heritage Foundation for Medical Research.
21. Hawkes, A. L., Pakenham, K. I., Chambers, S. K., Patrao, T. A., & Courneya, K. S. (2014). Effects
of a Multiple Health Behavior Change Intervention for Colorectal Cancer Survivors on Psychosocial
Outcomes and Quality of Life: a Randomized Controlled Trial. Annals of Behavioral Medicine, 1-12.
30
22. McCarroll, M. L., Armbruster, S., Frasure, H. E., Gothard, M. D., Gil, K. M., Kavanagh, M. B.,
Waggoner, S. & von Gruenigen, V. E. (2013). Self-efficacy, quality of life, and weight loss in
overweight/obese endometrial cancer survivors (SUCCEED): A randomized controlled
trial. Gynecologic oncology, 132, 397-402.
23. Demark-Wahnefried, W., Clipp, E.C., Morey, M., Pieper, C.F., Sloane, R., Clutter Snyder, D,
Cohen, H.J. (2006). Lifestyle intervention development study to improve physical function in older
adults with cancer: outcomes from project LEAD. Journal of Clinical Oncology, 24(21).
24. Von Gruenigen, V.E., Gibbons, H.E., Kavanagh, M.B., Janata, J.W., Lerner, E., Courneya, K.S.
(2009). A randomized trial of a lifestyle intervention in obese endometrial cancer survivors: quality of
life outcomes and mediators of behaviour change. Health and Quality of Life Outcomes, 7(17).
25. Carmody, J., Olendzki, B., Reed, G., Andersen, V., Rosenzweig, P. (2008). A dietary intervention
for recurrent prostate cancer after definitive primary treatment: Results of a randomized pilot trial.
Urology, 72(6).
26. Ravasco, P., Monteiro-Grill, I. & Camillo, M.E. (2003). Does nutrition influence quality of life in
cancer patients undergoing radiotherapy? Radiotherapy and Oncology, 67, 213-220.
27. Demark-Wahnefried, W., Rock, C. L., Patrick, K., & Byers, T. (2008). Lifestyle interventions to
reduce cancer risk and improve outcomes. American Family Physician, 77(11), 1573.
28. Pettersson, A., Johansson, B., Persson, C., Berglund, A., & Turesson, I. (2012). Effects of a dietary
intervention on acute gastrointestinal side effects and other aspects of health-related quality of life: A
randomized controlled trial in prostate cancer patients undergoing radiotherapy. Radiotherapy and
Oncology, 103(3), 333-340.
29. Daubenmeier, J.J., Weidner, G., Marlin, R., Crutchfield, L., Dunn-Emke, S., Chi, C., Gao, B.,
Carroll, P., Ornish, D. (2006). Lifestyle and Health-Related Quality of Life of men with prostate cancer
managed with active surveillance. Urology, 67(1), 125-130.
30. Bandura, A. (1986). Social Foundations of Thought and Action: A Social Cognitive Theory (1986
Edn). Prentice-Hall: Englewood Cliffs, Jew Jersey.
31. Prochaska, J.O and DiClemente, C.C. (1982) Transtheoretical Therapy: Toward a more integrative
model of change. Psychotherapy, Theory and Practice, 19(3), 276.
31
32. Satariano, W.A., Ragheb, N.E., Branch, L.G., et al. (1990). Difficulties in physical functioning
reported in middle-aged and elderly women with breast cancer: Case-control comparison, Journal of
Gerontology, 45, 3-11.
33. Morey, M.C., Snyder, D.C., Sloane, R. et al. (2009). Effects of Home-Based Diet and Exercise on
Functional Outcomes Among Older, Overweight Long-term Cancer Survivors: RENEW: A
Randomized Control Trial. The Journal of the American Medical Association, 301(18), 1883-1891.
34. Osoba, D. (1994). Lessons learned from measuring health-related quality of life in oncology.
Journal of Clinical Oncology, 12, 608-616.
35. Roberge, C., Tran, M., Massoud, C., Poirée, B., Duval, N., Damecour, E., Frout, D., Malvy, D.,
Joly, F., Lebailly, P., Henry-Amar, M. (2000). Quality of life and home enteral tube feeding: a French
prospective study in patients with head and neck or oesophageal cancer. British Journal of Cancer,
82(2), 263-269.
36. Wayne, S.J., Baumgartner, K., Baumgartner, R.N., Bernstein, L., Bowen, D.J., Ballard-Barbash, R.
(2006). Diet quality is directly associated with quality of life in breast cancer survivors. Breast Cancer
Research and Treatment. 96, 227-232.
37. Luutonen, S., Sintonen, H., Stormi, T., & Salminen, E. (2013). Health-related quality of life during
adjuvant radiotherapy in breast cancer. Quality of Life Research, 1-7.
38. Jacobs, M., Macefield, R. C., Elbers, R. G., Sitnikova, K., Korfage, I. J., Smets, E. M. A.,
Henselmans, I., van Berge Henegouwen, M.I., de Haes, J.C., Blazeby, J.M. & Sprangers, M. A. G.
(2013). Meta-analysis shows clinically relevant and long-lasting deterioration in health-related quality
of life after esophageal cancer surgery. Quality of Life Research, 1-22.
39. Conn, V. S., Valentine, J. C., & Cooper, H. M. (2002). Interventions to increase physical activity
among aging adults: a meta-analysis. Annals of Behavioral Medicine, 24(3), 190-200.
40. Eakin, E.G., Glasgow, R.E., Riley, K.M. (2000) Review of primary-care based physical activity
intervention studies: effectiveness and implications for practice and future research. Journal of Family
Practice, 49(2), 158-68.
41. Färkkilä, N., Torvinen, S., Roine, R. P., Sintonen, H., Hänninen, J., Taari, K., & Saarto, T. (2013).
Health-related quality of life among breast, prostate, and colorectal cancer patients with end-stage
disease. Quality of Life Research, 1-8.
32
42. Blanchard, C.M., Courneya, K.S. & Stein, K. (2008). Cancer survivors’ adherence to
lifestyle behaviour recommendations and associations with Health-Related Quality of Life: Results
from the American Cancer Society’s SCS-II. Journal of Clinical Oncology, 26(13), 2198-2204.
43. Ashing-Giwa, K.T., Lim, J-W., Gonzalez, P. (2010). Exploring the relationship between physical
well-being and healthy lifestyle changes among European and Latina American breast and cervical
cancer survivors. Psycho-Oncology, 19(11), 1161-1170.
44. McQuestion, M., Fitch, M., Howell, D. (2010). The changed meaning of food: Physical, social and
emotional loss for patients having received radiation treatment for head and neck cancer. European
Journal of Oncology Nursing, 1-7.
45. Blanchard, C.M., Denniston, K.S., Baker, F., Ainsworth, S., Courneya, K.S., Hann, D., Gesme, D.,
Reding, D., Flynn, T., Kennedy, J. (2003). Do adult cancer survivors change their lifestyle behaviours
once they are diagnosed with cancer? American Journal of Health Behaviour, 27, 246-256
46. Courneya, K. S., Jones, L. W., Mackey, I. R., & Fairey, A. S. (2006). Exercise beliefs of breast
cancer survivors before and after participation in a randomized controlled trial. International Journal of
Behavioural Medicine, 13(3), 259-264.
47. Moadel, A. B., Shah, C., Wylie-Rosett, J., Harris, M. S., Patel, S. R., Hall, C. B., & Sparano, J. A.
(2007). Randomized controlled trial of yoga among a multiethnic sample of breast cancer patients:
effects on quality of life. Journal of Clinical Oncology, 25(28), 4387-4395.
33