Download Cataract surgical outcomes, visual function and quality of life in four

Clinical and Experimental Ophthalmology 2011; 39: 119–125 doi: 10.1111/j.1442-9071.2010.02427.x
Original Article
ceo_2427
119..125
Cataract surgical outcomes, visual function and
quality of life in four rural districts in Vietnam
Leonard Yuen MD MRCOphth MPH,1 Nhu Hon Do MD PhD,2 Quoc Luong Vu MD,2 Sruti Gupta MD,3
Evelyn Ambrosio MD4 and Nathan Congdon MD MPH5
1
Singapore National Eye Centre, Singapore; 2Vietnam National Institute of Ophthalmology, Hanoi, Vietnam; 3School of Medicine, Johns
Hopkins University, Baltimore, Maryland, 4Helen Keller International, New York, New York, USA; and 5Zhongshan Ophthalmic Center,
Sun Yat-sen University, Guangzhou, China
ABSTRACT
Background: To evaluate cataract surgical outcomes
in four rural districts of Ha Tinh Province, Vietnam.
Design: Cross-sectional study.
Participants: Post-cataract surgery patients sampled
randomly from facilities in four rural districts of Ha
Tinh Province >3 months after surgery.
Main Outcome Measures: Postoperative visual acuity
(VA), visual function and quality of life.
Results: Among 412 patients, the mean age was
74.5 ⫾ 9.4 years, 67% (276) were female, and 377
(91.5%) received intraocular lenses (IOL). Nearly
two-thirds of patients had no postoperative visits
after discharge. Postoperatively, more than 40% of
eyes had presenting VA <6/18, while 20%
remained <6/60. The mean self-reported visual
function and quality of life for all patients were
68.7 ⫾ 23.8 and 73.8 ⫾ 21.6, respectively. Most
patients (89.5%) were satisfied with surgery and
the majority (94.4%) would recommend surgery to
others. One-third of patients paid ⱖ$US50 for
surgery. In multiple regression modelling, older age
(P < 0.01), intraoperative complications (P < 0.01)
and failure to receive an IOL (P < 0.01) were associated with postoperative VA <6/60.
Conclusion: Satisfaction with surgery was high, and
many patients were willing to pay for their
operations. Poor visual outcomes were common;
however, and better surgical training is needed to
reduce complications and their impact on visual
outcomes. More intensive postoperative follow-up
may also be beneficial.
Key words: cataract, epidemiology, quality of life,
Vietnam, visual function.
INTRODUCTION
Cataract remains the leading cause of blindness in
the world.1 It accounts for 65% of blindness in Vietnam2 and with an incidence of 87.6 cases per 100 000
persons annually, there are 70 870 new cases per
year.3 Vietnam has a large and rapidly aging population with over 86 million people (thirteenth most
populous in the world). Thus the already-significant
cataract burden will only worsen without additional
intervention.
National cataract surgical programmes have
proven able to significantly reduce the backlog of
un-operated blind4 but are highly dependent on
good output. In Vietnam, the cataract surgical rate
was 1362 cases per million population per annum
in 2006 (Personal correspondence with Dr Richard
Le Mesurier, FRCS, FRCOphth, Vision 2020
Regional Coordinator for the Western Pacific
Region). Although this figure is three times that of
China (450 cases per million population per
annum)5 it is significantly less than that of India
(4425).6
䊏 Correspondence: Professor Nathan Congdon, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China. Email:
[email protected]
Received 16 May 2010; accepted 23 August 2010.
© 2011 The Authors
Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists
120
Yuen et al.
In order to achieve the further increases in the
cataract surgical rate that will be needed to reduce
the backlog of cataract blindness in Vietnam, maximizing the quality of postoperative outcomes will be
critical. Previous studies have shown that cataract
surgery in rural Asia may often be associated with
poor visual outcomes,7–12 low visual function (VF),
and reduced quality of life (QOL).7,8,11 These undesirable results are particularly striking when compared with excellent results reported from urban
centres, such as in India.13,14 To date, there is little
information available on visual outcomes for cataract
surgery in Vietnam.15
Ha Tinh is among the poorest provinces of
Vietnam with 2008 Gross Domestic Product of
$US420/person/year.16 We report on postoperative
vision, VF and QOL for a sample of patients
undergoing extracapsular cataract extraction in Ha
Tinh Province. We also report the incidence of postsurgical complications, compliance of patients
with aftercare instructions, and the association of
patient and surgical factors with visual outcomes.
These data were collected by the Vietnam National
Institute of Ophthalmology (VNIO) and an international non-governmental organization, Helen
Keller International, before initiating a cataract surgical programme, and were designed to be representative of prevailing surgical outcomes at a
variety of facilities in Vietnam at the time of the
survey in 2003.
MATERIALS
AND METHODS
Twenty separate institutions including tertiary
government hospitals, local government facilities,
local private hospitals/clinics and eye camps run by
local government facilities were chosen as representative of surgical facilities in the four districts of Ha
Tinh (Thi xa Ha Tinh, Thi xa Hong Linh, Huyen
Nghi Xuan and Huyen Duc Tho). Random sampling
from surgical lists at these facilities was used to
identify 700 persons who had undergone cataract
surgery in one or both eyes between January and
December 2003. Among these, 412 subjects (58.9%)
could be located for examination and interviews at
commune health stations. These were conducted at
least 3 months after the patient’s latest operation,
with patients having had more recent surgery
excluded.
Oral informed consent was obtained for each
patient, and analysis of data was approved by the
Institutional Review Board of the Johns Hopkins
University School of Medicine. The Declaration
of Helsinki was followed throughout all study
procedures. Field work was conducted by two
clinical teams, each covering two of the four districts. Each team consisted of an ophthalmologist,
a supervisor, a team leader and two eye health
workers. The research teams underwent a 3-day
didactic and practical training course conducted by
the VNIO and Helen Keller International on interview, vision measurement and ocular examination
techniques.
Presenting visual acuity (VA) was measured for
each eye of all subjects using a Tumbling E Snellen
vision chart at a distance of 6 meters, with and
without pinhole. A slitlamp examination, including
dilation of the pupil, was performed by the team
ophthalmologist to identify the presence or absence
of an intraocular lens (IOL) and of surgical complications, including: posterior capsular opacification,
abnormalities of wound architecture, presence of an
irregular pupil, iris or vitreous adherent to the
wound, de-centration of the IOL, or persistent
corneal oedema.
All subjects were administered questions
adapted from the World Health Organization
Standard Cataract Survey Form regarding the date
and type of facility where the surgery was performed, the amount paid for surgery, duration of
admission, the number of postoperative visits and
compliance with postoperative instructions and
medications.
The VF and QOL interviews were conducted by
one of two trained interviewers. The VF-1417 was
used to assess VF, and the QOL questionnaire used
in the current survey was a Vietnamese-language
translation of an instrument developed for use
among cataract patients in rural southern India.18
These instruments have been previously described
elsewhere in detail. Briefly, the VF questionnaire
consisted of 11 questions within 4 subscales: visual
perception, peripheral vision, sensory adaptation
and depth perception. Subjects rated their function
and/or current vision problems in each of the 11
areas on a four point scale, from ‘not at all/very good’
(1) to ‘a lot/poor’ (4). The QOL questionnaire
included 12 questions within 4 categories: self care,
mobility, social interaction and mental well-being.
Subject responses were also on a 4-point scale, with
problems in each area rated as ‘none at all’ (1) to ‘a
lot’ (4). For both instruments, an aggregate score of
1–100 was the created, with 1 reflecting a maximum
difficulty level and 100 reflected the absence of any
difficulty.
Team supervisors reviewed all forms collected on
a daily basis for completeness, quality of entries and
consistency. The completed forms were then submitted to the VNIO Project Coordinators.
Statistical methods
Descriptive statistics (means, proportions, tables and
graphs) were completed using SPSS Builder (SPSS
© 2011 The Authors
Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists
Cataract surgical outcomes in Vietnam
Inc, Chicago, IL, USA) for age in years, gender,
number of follow-up visits postoperatively, number
of days in hospital and total patient cost. Presenting
VA was grouped into three categories: Good (6/6–6/
18), Borderline (<6/18–6/60) and Poor (<6/60). A
cumulated logistic model was used to analyse single
eye surgeries. Only the right eye was used in all
analyses for patients having bilateral surgery. ChiSquared test for the proportional odds assumption
was used to validate the assumption of independence for VA categories. This was not statistically
significant, indicating that the categories were independent from each other (c2 test with 8 degrees of
freedom = 10.8, P = 0.21).
Multiple logistic regression was performed for
factors that were associated with having postoperative presenting VA worse than 6/60. Covariates
included older age (years), operative complications,
IOL insertion, duration in hospital (days), hospital
type, cost of surgery ($US), time since surgery
(months), any postoperative follow-up visits and
gender. The VF and QOL scores were assessed against
age, gender and visual outcomes. P-value < 0.05 was
considered statistically significant.
RESULTS
The survey collected data from 412 patients, with a
mean age of 74.5 ⫾ 9.4 years and among whom
67% (276) were female. (Table 1) Surgery had been
performed on a single eye in 308 (74.8%) patients,
and 104 (25.2%) had undergone surgery in both
eyes. The IOLs were inserted in 377 (91.5%) eyes.
Only 12.6% of patients reported spending 3 or
fewer days in hospital postoperatively, and the
mean was 5.7 ⫾ 2.4 days (range 1 to 27 days).
(Table 1)
Nearly two-thirds (64.6%) of patients had no
further postoperative visits after discharge from the
surgical facility. (Table 1) Principal reasons included
‘felt follow-ups were unnecessary’ (n = 76, 32.7%),
‘forgot’ (n = 57, 24.6%), ‘distance or expense of
travel’ (n = 56, 24.1%) and ‘not informed of need to
follow up’ (n = 35, 15.1%).
Surgery was performed in local government hospitals in 18.9% of cases, eye camps in 56.8% and
tertiary government hospitals in 10.2%. About twothirds (64.8%) of patients reported paying <$US50
for surgery (Table 1). Median time since surgery was
24 months.
Postoperatively, 44% of eyes had presenting VA
better than 6/18, while 36% fell between <6/18 and
6/60, and 20% remained <6/60 after surgery. The
mean self-reported VF and QOL for all patients were
68.7 ⫾ 23.8 and 73.8 ⫾ 21.6, respectively, on a scale
of 0–100. (Table 1) The VA, VF and QOL outcomes
were better in Vietnam than has been reported for
121
Table 1. Demographic and clinical data for 412 subjects who
underwent cataract surgery in Ha Tinh, Vietnam
Factor
Age (years)
ⱕ50
51–60
61–70
71–80
>80
Gender
Male
Female
Hospital type
Local government hospital
Local private hospital / clinic
Tertiary hospital
Eye surgical camp
Other
Postoperative days in hospital
ⱕ3
4
5
6
7
ⱖ8
Postoperative visits
0
1
2
ⱖ3
Total amount paid for surgery ($US)
ⱕ20
21–49
50–99
ⱖ100
Data unavailable
Presenting postoperative visual acuity
>6/18
6/18–6/60
<6/60
Visual Function (mean ⫾ SD)
Quality of life (mean ⫾ SD)
Number
%
7
25
81
209
90
1.7
6.1
19.7
50.7
21.8
136
276
33.0
67.0
78
39
42
234
19
18.9
9.5
10.2
56.8
4.6
52
58
125
20
134
23
12.6
14.1
30.3
4.9
32.5
5.6
266
72
53
21
64.6
17.5
12.9
5.0
166
102
124
16
4
40.3
24.8
30.1
3.9
1
182
148
82
44
36
20
68.7 ⫾ 23.8
73.8 ⫾ 21.6
SD, standard deviation.
two population-based studies in rural China,7,8 but
not as good as those for a clinical series from an
urban centre in Southern India.14 (Table 2) Surgical
complications were recorded as present at the time of
follow-up examination for 14.6% (60/412) of operated eyes. (Table 3)
Among 408 patients responding to the question,
365 (89.5%) were satisfied with the surgery and 385
(94.4%) would recommend surgery to others.
Among those who were unsatisfied or unwilling to
recommend surgery, the principal reason was poor
visual outcome (79% [34/43] and 87% [20/23],
respectively.)
© 2011 The Authors
Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists
122
Yuen et al.
Table 2. Surgical outcomes among 412 persons undergoing cataract surgery in Ha Tinh, Vietnam as compared to figures reported from
studies in India and China
Outcome
Visual acuity worse than 6/60 (%)
Mean visual function score
Mean quality of life score
Ha Tinh, Vietnam
(current study)
Doumen, China6
Shunyi, China7
Aravind, India13
20
68.7 ⫾ 23.8
73.8 ⫾ 21.6
52.6
41.6 ⫾ 20.0
54.5 ⫾ 29.3
44.8
61.9 ⫾ 30.0
71.0 ⫾ 31.8
1.1
79.8 ⫾ 20.0
88.5 ⫾ 20.0
Note that visual function and quality of life scores vary from 1 (worst) to 100 (best).
Table 3. Surgical complications recorded at the time of follow-up examination. (Eyes may have had more than one complication: 60
subjects had any complication, and a total of 83 complications were reported)
Complications
Aphakia
Posterior capsule opacification
Uveitis
Iris trauma
Dislocated IOL
Persistent corneal oedema
Scleral erosion of the IOL
Number
% among 60 subjects
with complications
% among all
412 subjects
35
23
14
3
3
3
2
58.3%
38.3%
23.3%
5.0%
5.0%
5.0%
3.3%
8.5%
5.6%
3.4%
0.73%
0.73%
0.73%
0.49%
IOL, intraocular lens.
Table 4. Multiple logistic regression of factors potentially associated with having postoperative visual acuity >6/60 in 412 subjects who
underwent cataract surgery in Ha Tinh, Vietnam
Factor
Beta value
95% confidence interval
P-value
Older age (years)
Operative complications present
Intraocular lens inserted
Duration in hospital (days)
Hospital type†
Cost of surgery ($US)
Time since surgery (months)
Any postoperative follow-up visits
Female gender
-0.010
-0.212
0.210
0.0057
0.031
0.0001
0.00035
-0.34
0.486
-0.004, -0.016
-0.057, -0.367
0.001, 0.421
-0.239, 0.035
-0.017, 0.792
-0.001, 0.001
-0.002, 0.003
-0.488, 0.534
-0.012, 0.649
<0.01
<0.01
<0.01
0.71
0.20
0.24
0.80
0.57
0.70
Bold font indicates values significant at the <0.05 level. †Operated in tertiary government hospitals or in eye camps compared with
surgeries performed in local government hospitals or local private hospitals/clinics (denominator).
In multiple logistic regression modelling, increasing age (P = 0.002), intraoperative complications
(P = 0.007) and failure to receive an IOL (P = 0.001)
were significantly associated with presenting postoperative acuity <6/60 in the surgical eye. Gender,
time since surgery, time in hospital, amount paid for
surgery, having reported any follow-up visits, and
the type of hospital in which the patient was operated were unassociated with poor postoperative
vision (Table 4). Poor VF scores were associated with
having poor vision in the operated eye (P < 0.0001),
and with female gender (P = 0.03). Poor QOL scores
were associated with poor vision and older age
(P = 0.01) (Table 5).
DISCUSSION
The results of this study indicate that cataract surgical outcomes including acuity, self-reported VF and
QOL for a broad variety of settings in rural Vietnam
appear to be better than those reported for several
locations in rural China.7,8 However, one out of five
patients remained blind after surgery, a result which
compares poorly with major Asian urban centres
such as Aravind,14 and results recently reported
for rural Asian centres emphasizing high-quality
training.19
Besides self-reported VF and QOL, there are other
indices of patient satisfaction that are of importance
© 2011 The Authors
Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists
Cataract surgical outcomes in Vietnam
123
Table 5. Linear regression analyses for visual function score and quality of life as associated with visual acuity in the better eye, the
worse eye, age and gender
Visual function score
Vision in the better eye (<6/60 compared to ⱖ6/18)
Vision in the worse eye (<6/60 compared to ⱖ6/18)
Age
Gender
Quality of life score
Vision in the better eye (<6/60 compared to ⱖ6/18)
Vision in the worse eye (<6/60 compared to ⱖ6/18)
Age
Gender
to cataract surgical programmes. Recent evidence
suggests that positive word of mouth advertising is
of particular importance in patients’ willingness to
accept surgical services in rural Asia.20 In the current
study, 90% of patients were not only satisfied with
their own surgery, but would recommend it to
others. Given the relatively high proportion of
persons with poor postoperative results, the high
levels of self-reported satisfaction may reflect poor
preoperative vision (which we were unable to
assess). It is also significant that the primary reason
for not recommending surgery was failure to restore
sight in the patient’s eye.
Another important index of patient satisfaction for
programmes dependent on surgical revenues is
uptake of second eye surgery. The figure in this
cohort was only 25%, as compared to greater than
50% in other rural Asian self-pay cataract surgical
programmes with good outcomes.21 This is another
indication that satisfaction with surgical results may
not have been optimal in the current study, though
the lower uptake might also be due to cost, travel
distance or the lack of need for high-quality bilateral
vision in this population.
The results of this study have practical implications
for sustainable surgical programmes in Vietnam.
Patients are willing to pay substantial amounts for
cataract surgery: nearly 35% paid $US50 or more, a
figure consistent with the mean of $US55 reported by
willingness to pay studies in rural China.22 These
amounts are sufficient to cover the equipment, personnel and material costs in a surgical programme
taking full advantage of economies of scale.
Our results with regards to risk factors for poor
visual outcomes (postoperative vision worse than
6/60 in the operated eye) suggest specific strategies
for reducing the observed figure of 20% after surgery.
Surgical complications, an important determinant of
poor post-surgical vision in this setting, could be
reduced through additional training and surgeon
feedback. Training in appropriate case-selection may
also improve visual results. The finding that surgical
Beta value
-15.93
-1.24
-0.91
-2.21
Beta value
-9.51
0.02
-2.66
-1.67
95% confidence interval
-12.71,
1.81,
-0.82,
-0.36,
-19.66
-4.29
-1.00
-4.06
95% confidence interval
-5.96,
3.37,
-2.55,
0.37,
-13.06
-3.33
-2.77
-3.71
P-value
<0.001
0.22
0.36
0.03
P-value
<0.001
0.22
0.01
0.09
complications are prevalent and significantly associated with vision outcome echoes results from other
settings in rural Asia.8,9,23,24
The fact that failure to use an IOL is significantly
associated with poor outcomes suggests that further
increasing the already high (>90%) rate of pseudophakia will further reduce poor outcomes.
Aphakia and failure to optimize the resulting refractive error has been identified as among the most
common causes of poor postoperative vision in Asian
studies.8,10,11,23,24 Strong anecdotal evidence suggests
that the large majority of these patients received an
average-power IOL rather than one chosen on the
basis of biometry. It is likely that more widespread
use of biometry will reduce poor visual outcomes in
this setting.
A tendency towards long inpatient stays and relatively few outpatient postoperative visits was clearly
visible in our data: two-thirds of patients had no
visits after discharge. Though the postoperative
follow-up was not significantly associated with
visual outcome in this cohort, the observational
study design was subject to bias in this regard. The
question remains as to whether more comprehensive
follow-up might have improved outcomes. More
intensive follow-up implies additional costs to both
patients and hospitals. Services such as refraction21
and yttrium aluminium garnet (YAG) capsulotomy25
delivered at the time of follow-up may improve
vision, though uptake in rural Asian settings may be
low.21,25 Studies of scaled-back follow-up in the
developed world have not generally shown a significant impact on vision,26 but these are of uncertain
relevance in the developing world setting, where
postoperative follow-up can offer an opportunity to
identify and treat ocular comorbidities masked preoperatively by dense lens opacity.27
The results of this study must be understood
within the context of its limitations. Although
the sample was chosen to be representative of different venues for cataract surgery in four rural districts in Ha Tinh Province, Vietnam, it is not
© 2011 The Authors
Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists
124
Yuen et al.
population-based, as are some Asian studies of cataract surgical outcomes.7–10 The possibility of bias and
failure to accurately represent the population of
interest cannot be excluded.
As noted above, no controlled protocol was
employed for length of hospital stay or follow-up. The
possibility remains that failure to observe an association between these variables and visual outcome is
due to the fact that vision drove decisions about
inpatient stay or follow-up, rather than the reverse.
Though pinhole vision was measured, refraction
and best-corrected VA were not. It may, however, be
argued that presenting acuity is the most relevant
visual outcome in this setting in view of the modest
reported uptake of postoperative refractive services
even when available in rural Asia.21
Finally, ocular comorbidities and posterior capsular opacity, potentially important and remediable
cause of suboptimal postoperative visual outcomes in
rural Asia25,27 were not assessed in the current study.
Despite its limitations, the current report provides
data on cataract surgical outcomes in one of the
largest countries in Southeast Asia. These results
highlight the fact that patients are generally willing
to recommend surgery to others and often ready to
pay substantial amounts for operations, both of
which are of importance to programme planners in
Vietnam. Observed risk factors for poor outcomes
suggest some practical strategies to reduce the prevalence of postoperative blindness, which affected one
out of five patients in this setting.
ACKNOWLEDGEMENTS
A.
B.
C.
D.
Funding: This study was supported by a grant
from the Starr Foundation, New York City, NY,
USA.
Financial disclosures: None.
Contributions of authors: Design and conduct of
the study (NHD, QLV); collection, management,
analysis, and interpretation of the data (LY,
NHD, QLV, EA, NC); and preparation, review, or
approval of the manuscript (LY, NHD, QLV, SG,
EA, NC).
Statement of conformity with author information: Oral informed consent was obtained for
each patient, and analysis of data was approved
by the Institutional Review Board of the Johns
Hopkins University School of Medicine. The
Declaration of Helsinki was followed throughout all study procedures.
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© 2011 The Authors
Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists