Download Emergency Department Visits and Primary Care Among Adults With

ORIGINAL ARTICLE
Emergency Department Visits and Primary Care Among
Adults With Chronic Conditions
Jane McCusker, MD, DrPH,*† Danièle Roberge, PhD,‡§ Jean-Frédéric Lévesque, MD, PhD,¶
Antonio Ciampi, PhD,*† Alain Vadeboncoeur, MD,㛳 Danielle Larouche, MSc,‡
and Steven Sanche, MSc*
Background: An emergency department (ED) visit may be a
marker for limited access to primary medical care, particularly
among those with ambulatory care sensitive chronic conditions
(ACSCC).
Objectives: In a population with universal health insurance, to
examine the relationships between primary care characteristics and
location of last general physician (GP) contact (in an ED vs.
elsewhere) among those with and without an ACSCC.
Research Design: A cross-sectional survey using data from 2 cycles
of the Canadian Community Health Survey carried out in 2003 and
2005.
Subjects: The study sample comprised Québec residents aged ⱖ18
who reported at least one GP contact during the previous 12 months,
and were not hospitalized (n ⫽ 33,491).
Measures: The primary outcome was place of last GP contact: in an
ED versus elsewhere. Independent variables included the following:
lack of a regular physician, perceived unmet healthcare needs,
perceived availability of health care, number of contacts with doctors and nurses, and diagnosis of an ACSCC (hypertension, heart
disease, chronic respiratory disease, diabetes).
Results: Using multiple logistic regression, with adjustment for
sociodemographic, health status, and health services variables, lack
of a regular GP and perceptions of unmet needs were associated with
last GP contact in an ED; there was no interaction with ACSCC or
other chronic conditions.
Conclusions: Primary care characteristics associated with GP contact in an ED rather than another site reflect individual characteristics (affiliation with a primary GP and perceived needs) rather than
From the *Department of Clinical Epidemiology and Community Studies, St
Mary’s Hospital, Montreal, QC, Canada; †Department of Epidemiology,
Biostatistics and Occupational Health, McGill University, Montreal, QC,
Canada; ‡Centre de Recherche de l’Hôpital Charles LeMoyne, Longueuil,
QC, Canada; §Department des sciences communautaires de la Faculté de
Médecine, Université de Sherbrooke, QC, Canada; ¶Centre de recherche du
CHUM et Institut National de Santé Publique du Québec, Montréal, Canada;
and 㛳Emergency Medicine Services, Montreal Institute of Cardiology, Montreal, QC, Canada.
Supported by Fonds de la Recherche en Santé du Québec.
Presented at the Annual Meeting of the Canadian Association for Health
Services and Policy Research; May 11–14, 2009; Calgary, Alberta.
Reprints: Jane McCusker, MD, DrPH, Department of Clinical Epidemiology
and Community Studies, St. Mary’s Hospital, Montreal, Québec H3T
1M5, Canada. E-mail: [email protected].
Copyright © 2010 by Lippincott Williams & Wilkins
ISSN: 0025-7079/10/4811-0972
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the geographic availability of healthcare, both among those with and
without chronic conditions.
Key Words: emergency department, primary care, chronic
disease, cross-sectional study
(Med Care 2010;48: 972–980)
T
he emergency department (ED) plays multiple functions
for populations with chronic conditions. It provides a
source of care in medical, surgical, and traumatic emergencies, but also functions as an alternative source for primary
medical care.1 Certain characteristics of primary care (eg,
lack of a regular physician, unmet needs for healthcare, poor
continuity of care, perceived lack of rapid access to care)
have been associated with an increased likelihood of making
an ED visit,2– 8 although the evidence is inconsistent.9 Even
under Canada’s universal health insurance program there may
be differential access to primary care; certain population
subgroups (recent immigrants, those with serious mental
health problems) may be more likely to seek care in the ED
than in other ambulatory care settings.10 Certain chronic
medical conditions (eg, diabetes, asthma, congestive heart
failure) are considered to be particularly sensitive to access to
primary care services; hospitalization rates for these conditions are used in many jurisdictions as an indicator of limited
access to primary care.11 Better primary care management of
these conditions may improve the process of care and clinical
outcomes12–14 and is hypothesized to reduce the probability
of complications or clinical deterioration that could lead to an
ED visit or hospitalization.11,15
Most research on ambulatory care sensitive chronic
conditions (ACSCC) has examined ACSCC-hospitalization
rates in relation to access to care,16 and among population
groups with lower access to care, including racial or ethnic
minority groups,17 and low income populations.18 However,
the evidence relating ACSCC hospitalizations to characteristics of primary care is inconsistent and requires further
validation.9,19 In US studies of those aged less than 65, rates
of ACSCC-related ED visits are higher among Medicaid
beneficiaries and racial minority groups.20 Among Medicaid
beneficiaries, rates of ACSCC-related ED visits are higher
among those without a regular source of care,21 and those
who receive treatment outside community health centers.22
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Medical Care • Volume 48, Number 11, November 2010
In this research, we aimed to extend this research to a
population with universal health insurance, including all age
groups, in the province of Québec, Canada. International
comparative studies indicate that Québec has among the
highest rates of ED visits, the lowest proportion with a
regular family doctor, poor perceived accessibility by telephone to a family doctor, and the longest waiting times for an
appointment.23 In a telephone survey, more than one-third of
those who reported an ED visit considered that the problem
could have been treated by their family physician, if available.1 We used pooled data from 2 population health surveys
in Québec to investigate the relationship between primary
care characteristics and use of the ED among those with and
without ACSCC. Specifically, the surveys provide self-reported information on the location of last contact with health
professionals, in an ED or elsewhere. We hypothesized that
the relationships between characteristics of primary care and
last general physician (GP) contact in an ED would be
stronger in the population with ACSCC than among those
with other or no chronic conditions.
METHODS
Data were derived from the combined Canadian Community Health Survey cycles 2.1 and 3.1, carried out in 2003
and 2005, respectively.24 The study sample comprised Québec residents aged ⱖ18. The Canadian Community Health
Survey (CCHS) is a probability sample of Canadian residents
aged 12 and over, excluding those in Indian Reserves, Crown
lands, institutions or certain remote regions, and full-time
members of the Canadian Forces. In cycle 3.1 (similar to 2.1)
3 sampling frames were used: an area frame (49%), a telephone frame (50%), and a random digit dialing frame (1%).
A multistage sample was selected from the area frame,
stratifying on socioeconomic and geographical variables,
while clustering on household groups. Sampling from the
telephone frame was random within health regions. The
interviews were computer assisted and were achieved in
person for the sample coming from area frame, and by
telephone for the rest of the total sample. The Québec
response rates were of 82.6% for the area frame and 72.5%
for interviews over the telephone, for an overall response rate
of 76.4%. A priori oversampling as well as a posteriori
weighting adjustments corrected for nonresponse. As the 2
survey cycles include identical questions, they were combined for increased statistical power. Note that there was a
very low probability of the same individual participating in
both surveys.
Outcome Variables
Participants were asked a series of 3 questions: (1) “In
the past 12 months, have you been a patient overnight in a
hospital, nursing home, or convalescent home?” (2) “Not
counting when you were an overnight patient, in the past 12
months, how many times have you seen or talked on the
telephone about your physical, emotional, or mental health
with a family doctor or general practitioner?” (3) among
those with at least one such contact: “Where did the most
recent contact take place?” The primary outcome (last GP
contact in an ED) was defined, among participants with one
© 2010 Lippincott Williams & Wilkins
Emergency Department Visits
or more GP contacts, as the location of last GP contact: in an
ED versus all other locations. This measure was highly
correlated with an equivalent measure derived from the provincial physician claims database, among 20 subgroups defined by 5 age and 4 rural-urban residence groups (Pearson’s
r ⫽ 0.89; unpublished data). This cross-validation revealed a
systematic effect of age but not of residence, suggesting
greater underreporting of last GP contact in an ED among
those aged ⱖ65 compared with other age groups.
In Québec, the great majority of physicians who work
in EDs are GPs. However, as patients are probably unaware
of the specialty of the physician seen at an ED visit, we
analyzed 2 secondary outcomes: location of last contact with
specialists and nurses, based on a similar sequence of questions as the primary outcome. Specialist contacts were those
with “any other medical doctor, such as a surgeon, allergist,
orthopedist, gynecologist, or psychiatrist”; nurse contacts
were those with “a nurse for care or advice.” Because it was
impossible to determine whether or not the last ED contact
resulted in hospitalization, we restricted our analyses of place
of last contact to participants who reported no hospital admission during the past 12 months. We also conducted
sensitivity analyses of the primary outcome that included
those with a history of hospitalization.
Independent Variables
Sociodemographic Variables
Age was analyzed as a 5-level categorical variable
(18 –24, 25–34, 35– 44, 45– 64, 65⫹). Marital status was
grouped in 3 categories: never married; divorced, separated,
or widowed; common-law or married). Immigration status
was grouped in 4 categories: born in Canada, 5 or fewer
years, 6 to 10, and more than 10 years. Educational attainment was classified as follows: no secondary diploma, secondary diploma, some postsecondary studies, postsecondary
diploma); income was defined as family income adjusted for
family size, in quartiles. The area of residence was a 7-level
variable measuring the influence of large urban core areas on
residence and place of work from the highest (residence
inside or close to a major urban core) to the lowest (areas with
no major urban core influence).25 We aggregated levels 2, 3,
and 4 because (1) the primary outcome was similar in these 3
levels, and (2) this led to the best fit (see statistical methods).
Health Status
Chronic conditions diagnosed by a doctor were classified into 3 categories: ACSCC (one or more of 5 conditions—
diabetes, hypertension, asthma, chronic obstructive pulmonary disease, heart disease)16; other chronic conditions only;
or no chronic conditions. We also created a measure of the
total number of chronic conditions. Respondents reported
their perceived general health status (fair or poor vs. good,
very good, or excellent), health change during the past 12
months (worse vs. the same or better). Activity limitation was
the extent to which the individual was limited in their usual
activities (never, sometimes, often). Dependence in activities
of daily living was a 3-category hierarchical variable: none,
dependence only in instrumental activities (preparing meals,
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McCusker et al
Medical Care • Volume 48, Number 11, November 2010
getting to appointments, housework, heavy household chores,
personal finances), and dependence in basic activities of daily
living (moving around inside the house, personal care). A
measure of psychologic distress was used to identify respondents with potentially serious mental illnesses.26 High alcohol
consumption was defined as reporting 5 or more consecutive
drinks at least once a week.
Health Services
Two measures of primary care were defined as dichotomous variables: a regular or family physician (yes, no),
unmet healthcare needs (yes, no). We also analyzed the
perceived availability of healthcare in the community (excellent, good, or fair vs. poor); this variable was only available
in cycle 2.1. Measures of health services utilization included
the following receipt of homecare services (yes, no), and
numbers of contacts during the past 12 months with GPs
(none, 1, 2–3, 4, or more), specialists (none, 1–2, 3, or more),
and nurses for care/advice (none, 1, 2, or more).
Statistical Methods
Combination of the 2 CCHS surveys involved sampling
and bootstrap weights. These weights were divided by 2,
reflecting equal importance of the 2 surveys.27 Sampling
weights were used in the calculation of the estimates to
correct for the sampling design and nonresponse. We used
bootstrap weights to obtain the variance of the estimates
because no exact formula is available.28
We used multiple logistic regression models for predicting the primary outcome, last contact with a GP in an ED,
using the independent variables. The initial models reported
were adjusted for age and sex. Further logistic regression
modeling of the primary outcome was conducted in 2 stages
with the following independent variables: (1) age, sex, number of contacts with a GP, chronic conditions, and health
services variables; (2) all independent variables. Interactions
between chronic conditions and the other independent variables were also examined. For all multivariate modeling
stages, we selected variables using Bayesian model averaging
(BMA),29 a procedure accounting for the uncertainty in the
model choice by selecting all likely models. If the BMA
procedure suggested more than 1 model, the models with a
posteriori probabilities of 5% or more were investigated. Age,
sex, chronic conditions, and number of contacts with a GP
were preselected in each model. Because of the complex
nature of the CCHS sampling methodology, all the BMA
selected models were further analyzed using logistic regression for complex surveys, as implemented in the SUDAAN
software; this provides correct usage of bootstrap weights, as
described above. Although we examined all models selected
by the BMA, we used the minimum Akaike Information
Criterion and minimum Bayesian Information Criterion to
select 2 final models; one model with and one without
interactions. All likely models without interactions exhibited
similar parameter estimates and confidence intervals (CIs),
and had similar Akaike Information Criterion and Bayesian
Information Criterion values. Therefore, we present the most
complete model containing all variables considered in the
BMA output. When considering models with interactions, as
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FIGURE 1. Derivation of study sample. CCHS indicates Canadian Community Health Survey; ED, emergency department;
GP, general physician. *Includes overnight stay in hospital,
nursing home, or convalescent home.
there was little parameter variability between these 2 chosen
models, we chose to present the simpler of the 2 while
describing interactions of interest. We used similar methods
for the sensitivity analyses that included the sample with a
history of hospitalization. The secondary analyses of place of
last contact with specialists and nurses were adjusted for age
and sex only, because of the more restricted sample sizes.
RESULTS
Figure 1 shows the steps in the selection of the sample
of participants with at least one GP contact during the
previous 12 months (n ⫽ 33,491), of whom 1677 (5.0%)
reported their last contact in an ED. Table 1 shows the results
of the initial and multivariate logistic regression models of
the primary outcome. In the initial age- sex adjusted models,
sociodemographic variables associated with last GP contact
in an ED included: age under 35, male, a low level of
education, and living in an area with a lower metropolitan
influence. Among the health status measures, absence of a
chronic condition, deteriorating health, and high alcohol consumption were associated with last GP contact in an ED.
Health services variables associated with last GP contact in
an ED were nurse contacts in last 12 months, lack of a
regular GP, and unmet healthcare needs. Notably, neither
the perceived availability of health care in the community
nor the total number of contacts with a GP were related to
the place of last contact. For simplicity, we have not
presented results for the following variables that were not
significant in initial models and were not selected for the
© 2010 Lippincott Williams & Wilkins
Medical Care • Volume 48, Number 11, November 2010
Emergency Department Visits
TABLE 1. Odds Ratios and 95% Confidence Intervals for Associations With Last General Physician Contact in an Emergency
Department, in the Past 12 Months (n ⫽ 33,491)
Initial Models†
Variable
Sociodemographic variables
Age
18–24
25–34
35–44
45–64
65⫹
Sex
Female
Male
No. years living in Canada
Born in Canada
5 or less
Between 6 and 10
More than 10
Education
No secondary diploma
Secondary diploma
Some post secondary studies
Post secondary diploma
Area of residence
CMA
CA or strong CMA/CA influence
Moderate CMA/CA influence
Weak CMA/CA influence
No CMA/CA influence
Health status
Chronic condition
No chronic condition
Has an ACSCC
Has a chronic condition but not an ACSCC
No. chronic conditions
No chronic condition
1 or 2 chronic conditions
3 or more chronic conditions
Perceived health status
Fair or poor
Excellent, very good, or good
Perceived health changes during the past 12 months
Worse or much worse
Much better, better, or about the same
High alcohol consumption
No
Yes
Health services
No. contacts with a GP (past 12 mo)
1
2 or 3
4 or more
© 2010 Lippincott Williams & Wilkins
Final Model
%*
OR
95% CI
OR
95% CI
10.6
14.7
19.8
37.3
17.6
1.00
0.80
0.46
0.25
0.11
—
(0.63, 1.00)
(0.35, 0.60)
(0.19, 0.31)
(0.08, 0.17)
1.00
0.84
0.59
0.40
0.18
—
(0.65, 1.08)
(0.43, 0.80)
(0.29, 0.53)
(0.11, 0.29)
54.5
45.5
1.00
1.61
—
(1.35, 1.92)
1.00
1.25
—
(1.03, 1.50)
88.7
1.7
1.4
8.2
1.00
0.79
0.26
0.83
—
(0.43, 1.48)
(0.10, 0.73)
(0.51, 1.33)
13.4
8.8
5.4
72.4
1.44
0.96
1.36
1.00
(1.03, 2.01)
(0.72, 1.29)
(0.97, 1.92)
—
67.3
17.7
10.8
3.6
0.6
1.00
1.64
1.82
2.88
4.23
—
(1.35, 2.00)
(1.40, 2.36)
(2.20, 3.76)
(2.02, 8.86)
1.00
1.94
2.38
3.27
5.42
—
(1.56, 2.40)
(1.80, 3.16)
(2.44, 4.40)
(2.24, 13.11)
26.5
31.2
42.3
1.00
0.68
0.81
—
(0.54, 0.87)
(0.66, 0.99)
1.00
0.72
0.80
—
(0.55, 0.93)
(0.65, 0.99)
26.9
46.7
26.4
1.00
0.72
0.92
—
(0.59, 0.88)
(0.71, 1.17)
11.2
88.8
0.94
1.00
(0.68, 1.30)
—
11.9
88.1
1.45
1.00
(1.10, 1.90)
—
1.39
1.00
(1.02, 1.89)
—
97.7
2.3
1.00
1.65
—
(1.03, 2.64)
1.00
1.52
—
(0.96, 2.38)
38.9
37.8
23.3
1.00
1.18
0.90
—
(0.97, 1.45)
(0.70, 1.16)
1.00
1.23
0.92
—
(0.98, 1.53)
(0.68, 1.25)
(Continued)
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McCusker et al
TABLE 1. (Continued)
Initial Models†
Variable
No. contacts with a specialist (past 12 mo)
No contact
1 or 2
3 or more
No. contacts with a nurse for care or advice (past 12
mo)
No contact
1
2 or more
Regular GP
No
Yes
Unmet healthcare needs
No
Yes
Perceived availability of services in the community‡
Poor
Excellent, good, fair
Final Model
%*
OR
95% CI
OR
95% CI
66.2
25.6
8.2
1.00
0.94
0.89
—
(0.74, 1.19)
(0.62, 1.28)
84.7
8.1
7.2
1.00
1.38
1.55
—
(1.04, 1.83)
(1.21, 2.00)
1.00
1.36
1.48
—
(0.99, 1.87)
(1.11, 1.99)
15.8
84.2
4.54
1.00
(3.70, 5.56)
—
4.58
1.00
(3.67, 5.72)
—
86.4
13.6
1.00
1.64
—
(1.31, 2.06)
1.00
1.38
—
(1.06, 1.80)
14.5
85.5
1.33
1.00
(0.88, 1.99)
—
*Estimated percent of the Québec population, aged 18 and over, with one or more GP contacts in the past 12 months.
†
Odds ratios are adjusted for age and sex.
‡
Sample restricted to respondents from CCHS cycle 2.1 (2003) only.
ACSCC indicates Ambulatory care sensitive condition; CMA, Census metropolitan area; CA, Census agglomeration; GP, General physician; OR, Odds Ratios; CI, Confidence
Intervals.
final models: marital status, income, activity limitations,
dependence in activities of daily living, psychologic distress, and receipt of home care.
In the final multivariate model without interactions,
variables that continued to be statistically significant predictors of last GP contact in an ED were: age younger than 35,
male sex, residence further from a metropolitan area, absence
of a chronic condition, worsening health, 2 or more contacts
with a nurse, absence of a regular physician, and unmet
healthcare needs. The associations with absence of a regular
GP physician and with chronic conditions were similar to
those in the initial models, whereas that with unmet needs
was somewhat attenuated.
The best-fitting model with interactions (not shown) included a strong interaction between chronic conditions and sex
(P ⬍ 0.01), indicating that the association of male sex with ED
contact was restricted to those without a chronic condition (odds
ratio 关OR兴: 1.75 关95% CI: 1.26; 2.41兴). In further exploration of
this interaction, we found that inclusion of injuries in the model
resulted in attenuation of the OR for male sex in the group with
no chronic conditions (data not shown). A second strong interaction was between lack of a regular GP and area of residence
(P ⬍ 0.01). The ORs for lack of a regular GP for all except the
most rural subgroup were strong and statistically significant,
whereas the OR for the most rural subgroup was weaker and
nonsignificant (OR: 1.87, 关95% CI: 0.40, 8.82兴). A weaker
interaction was found with number of nurse contacts (P ⫽ 0.07),
indicating that, among those with no chronic conditions, a single
nurse contact was associated with last GP contact in an ED (OR:
2.23 关95% CI: 1.37; 3.64兴). The BMA procedure selected an
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interesting but nonsignificant interaction (P ⫽ 0.33), suggesting
that unmet needs are associated with ED contact only among
those with an ACSCC or other chronic conditions (OR: 1.69
关95% CI: 0.96; 2.97兴 and OR: 1.64 关95% CI: 1.17; 2.30兴,
respectively, compared with OR: 1.00 关95% CI: 0.58; 1.73兴
among those without any chronic condition). There was no
interaction between lack of regular GP and chronic conditions
(P ⫽ 0.63); the ORs were similar and strong among participants
with and without ACSCC or other chronic conditions.
Sensitivity analysis that included hospitalized individuals yielded very similar results to those presented above
(data not shown). In the main model, the effects of lack of
regular GP (OR: 4.23, 95% CI: 3.43, 5.21) and unmet needs
(OR) 1.28 (95% CI: 1.01, 1.63) remained significant. Interestingly, there was an interaction between unmet needs and
hospitalization, such that the association with GP last contact
in an ED was observed only for individuals without hospitalization, supporting our decision to exclude hospitalized
persons in our primary analysis.
Table 2 shows the results of the secondary analyses of
place of last contact with specialists and with nurses for
care/advice. In general, the associations of the sociodemographic and health status variables with these outcomes were
similar to those found for the primary outcome, whereas there
were notable differences for some of the health service
variables. The OR for lack of a regular GP was lower for both
secondary outcomes, although it remained significant for last
nurse contact. Unmet needs were associated with place of last
nurse contact but not last specialist contact. Two or 3 GP
contacts were associated with a lower odds of last specialist
© 2010 Lippincott Williams & Wilkins
Medical Care • Volume 48, Number 11, November 2010
Emergency Department Visits
TABLE 2. Odds Ratios* and 95% Confidence Intervals for Associations With Last Specialist and Last Nurse Contact in an
Emergency Department, in the Past 12 Months
Specialist†
(n ⴝ 13,624)
Variable
Sociodemographic variables
Age
18–24
25–34
35–44
45–64
65⫹
Sex
Female
Male
No. years living in Canada
Born in Canada
5 or less
Between 6 and 10
More than 10
Education
No secondary diploma
Secondary diploma
Some post secondary studies
Post secondary diploma
Area of residence
CMA
CA or strong CMA/CA influence
Moderate CMA/CA influence
Weak CMA/CA influence
No CMA/CA influence
Health status
Chronic condition
No chronic condition
Has an ACSCC
Has a chronic condition but not an ACSCC
No. chronic conditions
No chronic condition
1 or 2 chronic conditions
3 or more chronic conditions
Perceived health status
Fair or poor
Excellent, very good, or good
Perceived health changes during the past 12 months
Worse or much worse
Much better, better or about the same
High alcohol consumption
No
Yes
Health services
No. contacts with a GP (past 12 mo)
No contact
1
2 or 3
4 or more
© 2010 Lippincott Williams & Wilkins
Nurse‡
(n ⴝ 6962)
OR
95% CI
OR
95% CI
1.00
0.94
0.86
0.63
0.80
—
(0.61, 1.44)
(0.56, 1.32)
(0.40, 0.98)
(0.52, 1.23)
1.00
0.94
0.54
0.59
0.27
—
(0.62, 1.41)
(0.36, 0.82)
(0.40, 0.87)
(0.16, 0.45)
1.00
1.90
—
(1.49, 2.42)
1.00
2.32
—
(1.75, 3.08)
1.00
1.16
0.77
0.48
—
(0.41, 3.30)
(0.11, 5.63)
(0.24, 0.97)
1.00
0.86
0.44
1.11
—
(0.24, 3.14)
(0.02, 10.38)
(0.43, 2.84)
2.02
1.17
1.20
1.00
(1.21, 3.37)
(0.78, 1.75)
(0.64, 2.26)
—
1.62
1.62
1.53
1.00
(0.90, 2.94)
(1.01, 2.59)
(0.62, 3.80)
—
1.00
1.72
2.12
2.67
2.69
—
(1.18, 2.50)
(1.48, 3.04)
(1.75, 4.05)
(1.39, 5.21)
1.00
1.41
2.10
3.48
0.61
—
(1.00, 2.00)
(1.39, 3.19)
(2.16, 5.61)
(0.11, 3.26)
1.00
0.81
0.69
—
(0.58, 1.14)
(0.49, 0.96)
1.00
1.02
0.66
—
(0.67, 1.56)
(0.45, 0.97)
1.00
0.75
0.66
—
(0.54, 1.05)
(0.48, 0.93)
1.00
0.78
0.68
—
(0.54, 1.14)
(0.44, 1.05)
0.86
1.00
(0.60, 1.22)
—
0.91
1.00
(0.55, 1.50)
—
1.25
1.00
(0.91, 1.72)
—
1.43
1.00
(0.95, 2.14)
—
1.00
1.44
—
(0.68, 3.06)
1.00
0.76
—
(0.36, 1.60)
1.00
0.88
0.69
0.95
—
(0.64, 1.21)
(0.48, 0.99)
(0.68, 1.34)
1.00
0.96
0.98
0.89
—
(0.63, 1.45)
(0.65, 1.49)
(0.60, 1.31)
(Continued)
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McCusker et al
TABLE 2. (Continued)
Specialist†
(n ⴝ 13,624)
Variable
No. contacts with a specialist (past 12 mo)
No contact
1 or 2
3 or more
No. contacts with a nurse for care or advice (past 12
mo)
No contact
1
2 or more
Regular GP
No
Yes
Unmet healthcare needs
No
Yes
Perceived availability of services in the community§
Poor
Excellent, good, fair
Nurse‡
(n ⴝ 6962)
OR
95% CI
OR
95% CI
—
1.00
0.82
—
—
(0.60, 1.11)
1.00
0.88
0.66
—
(0.63, 1.24)
(0.40, 1.10)
1.00
1.25
1.42
—
(0.88, 1.78)
(0.96, 2.10)
—
1.00
0.71
—
—
(0.53, 0.95)
1.23
1.00
(0.92, 1.69)
—
1.49
1.00
(1.06, 2.08)
—
1.00
1.13
—
(0.82, 1.56)
1.00
1.67
—
(1.17, 2.38)
1.22
1.00
(0.77, 1.93)
—
1.54
1.00
(0.73, 3.27)
—
*Odds ratios are adjusted for age and sex.
†
Sample consists of respondents with one or more specialist contacts in the last 12 months.
‡
Sample consists of respondents with one or more nurse contacts for care or advice in the last 12 months.
§
Sample restricted to respondents from CCHS cycle 2.1 (2003) only.
ACSCC indicates Ambulatory care sensitive condition; CMA, Census metropolitan area; CA, Census agglomeration; GP, General physician; OR, Odds Ratios; CI, Confidence
Intervals.
contact in an ED; more than 2 nurse contacts was associated
with a lower odds of last nurse contact in an ED.
DISCUSSION
We pooled data from 2 population health surveys conducted in the province of Québec, Canada, to investigate the
relationships between characteristics of primary care and last
doctor or nurse contact in an ED, among those with and
without ambulatory care sensitive or other chronic conditions. Four features of this study make new contributions to
knowledge. First, we focused on ambulatory ED visits (that
did not lead to hospitalization), which may be more sensitive
to primary care services than are ED visits with hospitalization.1 Second, the sample was not limited to those under 65 or
with particular types of health insurance, but was a representative population sample of all adults aged 18 and over. Third,
the study was conducted in a population with universal health
insurance, which may have implications for the expansion of
health insurance coverage in the US. Fourth, unlike previous
research, we investigated ED visits in the population with
ACSCC, and not ACSCC-related ED visits. Diagnostic information collected at ED visits may not be valid; a more
complete picture of ED utilization avoids this bias. Finally,
we compared individuals with selected ACSCC with those
with other or no chronic conditions. In general, the outcomes
were similar in the 2 chronic condition groups, suggesting
that ACSCC are not more sensitive than other chronic conditions to limited access to primary care.
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We found that 2 measures of inadequate primary care
were associated with last GP contact in an ED, even after
adjustment for covariates including sociodemographics,
health status, and number of GP contacts: lack of a regular
GP and perceived unmet needs. Lack of a regular GP was
strongly associated with last GP contact in an ED, both
among those with and without chronic conditions. Having a
regular or primary physician is associated with better perceived access to care9,30 and greater utilization of preventive
services.8,31 Primary care physicians may also play a role in
reducing unnecessary health service utilization and
costs.8,32,33 We found a similar but weaker association between lack of a regular GP and place of last contact with a
nurse, but not with place of last contact with a specialist.
Patients may be more likely to recall that they saw a specialist
in the ED whether they are referred to an ED by a specialist.
Perceptions of unmet healthcare needs increased the
odds of last GP contact in an ED, but only among those
without prior hospitalization. This finding suggests that ambulatory ED visits are more likely to substitute for regular
primary care than do those at which the patient is hospitalized.1 After adjustment for covariates, the relationship of
unmet needs with place of last GP contact was attenuated and
appeared to be limited to subgroups with ACSCC and other
chronic conditions (although only the CIs for non-ACSCC
chronic conditions exclude unity.) Unmet needs are increasing in Canada. Although multiple factors contribute to perceptions of unmet need, in Québec, this variable appears to
© 2010 Lippincott Williams & Wilkins
Medical Care • Volume 48, Number 11, November 2010
reflect mainly a perceived lack of accessibility to health care
(eg, long waiting times).34
As reported elsewhere, we found important rural-urban
differences in use of the ED.7 A more rural residence was
associated with an increased likelihood of contacting any
health professional (GP, specialist, or nurse) in an ED. Furthermore, the effect of lack of a regular GP was strong in all
regions except the most rural. In a previous Québec study,
greater continuity of care with a primary physician was
associated with fewer ED visits; this relationship was stronger in urban versus rural areas.2 Rural primary care differs
from that in urban areas; rural physicians are more likely to
practice in multiple locations, including the ED, which becomes an additional site for primary care.7
Overall, these results provide little support for the
hypothesis that ambulatory ED visits among adults with
ACSCC are more sensitive to characteristics of primary care
than are ED visits in those with other or no chronic conditions. Researchers in the United States have also questioned
the validity of this hypothesis in relation to hospitalization
data.9,19 Differences in our study results from those of prior
research20 –22 may be due to differences in methodology (eg,
measurement of ACSCC) or the study population (eg, representative population sample, healthcare system differences,
inclusion of all age groups).
Limitations of this study include those of any crosssectional survey, including the potential for recall bias. Several potential limitations implicit in the survey design should
also be noted. First, our primary measure of place of last GP
contact was limited to those who reported GP contacts, 62.7%
of the survey population aged 18 and over. Although participants may not have recalled correctly the type of health
professional they contacted, and probably underreported
health professional contacts in an ED, our cross-validation
suggests that this measure is valid in general. The relatively
greater underreporting of the outcome among those aged 65
and over may be explained by impaired memory as well as
higher rates of physician contact. Second, no information was
available on a regular site of care; having a regular physician
may be less important among those with a site of care.9 Third,
no information was collected on the reasons for the ED
contact. However, there is no reason to think that the frequency of ED visits for problems unrelated to chronic conditions (eg, trauma) would differ among those with and
without chronic conditions.
There are several implications of the study for health
policy. First, the proportion of GP contacts in the ED may be
a useful indicator of the accessibility of primary health care
services.10 Use of this indicator should take into account the
differences in primary care practice in rural versus urban
populations. Second, primary care characteristics associated
with whether care is obtained in an ED rather than another
site reflect individual characteristics (affiliation with a primary GP and perceived needs) rather than the geographic
availability of healthcare. Prior research in Québec seniors
found that although increased provider continuity was associated with decreased ED visits, greater availability of physicians in an area (the physician-population ratio) was para© 2010 Lippincott Williams & Wilkins
Emergency Department Visits
doxically associated with greater ED utilization.2 Therefore,
primary care reform should aim to increase affiliation with a
regular physician, or at least a regular source of care, if the
goal is to reduce the use of the ED as a source of primary
care.23 Additional strategies to support this goal include
group practice, multidisciplinary teamwork, and mechanisms
to coordinate services.35 Notably, the experiences of Kaiser
Permanente and the Veterans Administration suggest that
improving the integration of primary care with other levels of
care make it possible to reduce utilization of hospital and ED
services.36,37
ACKNOWLEDGMENTS
While the research and analysis are based on data from
Statistic Canada, the opinions expressed do not represent the
views of Statistics Canda.
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