Context Some have argued that Canada's uniquely restrictive approach to private
health insurance keeps the socioeconomic elite inside the public system so
that their demands and influence elevate the standard of service for all Canadian
citizens. The extent to which this theory is a valid representation of Canadian
health care is unknown.
Objectives To explore how patients with acute myocardial infarction from different
socioeconomic backgrounds perceive their care in Canada's universal health
care system and to correlate patients' backgrounds and perceptions with actual
Design, Setting, and Patients Prospective observational cohort study with follow-up telephone interviews
of 2256 patients 30 days following acute myocardial infarction discharged
from 53 hospitals across Ontario, Canada, between December 1999 and June 2002.
Main Outcome Measures Postdischarge use of cardiac specialty services; satisfaction with care;
willingness to pay directly for faster service or more choice; and mortality
according to income and education, adjusted for age, sex, ethnicity, clinical
factors, onsite angiography capacity at the admitting hospital, and rural-urban
Results Compared with patients in lower socioeconomic strata, more affluent
or better educated patients were more likely to undergo coronary angiography
(67.8% vs 52.8%; P<.001), receive cardiac rehabilitation
(43.9% vs 25.6%; P<.001), or be followed up by
a cardiologist (56.7% vs 47.8%; P<.001). Socioeconomic
differences in cardiac care persisted after adjustment for confounders. Despite
receiving more specialized services, patients with higher socioeconomic status
were more likely to be dissatisfied with their access to specialty care (adjusted
RR, 2.02; 95% confidence interval, 1.20-3.32) and to favor out-of-pocket payments
for quicker access to a wider selection of treatment options (30% vs 15% for
patients with household incomes of Can $60 000 or higher vs less than
Can $30 000, respectively; P<.001). After
adjusting for baseline characteristics, socioeconomic status was not significantly
associated with mortality at 1 year following hospitalization for myocardial
Conclusions Compared with those with lower incomes or less education, upper middle-class
Canadians gain preferential access to services within the publicly funded
health care system yet remain more likely to favor supplemental coverage or
direct purchase of services.
Canada's universal health insurance system provides comprehensive coverage
for most medical and hospital services without user fees at point of service.
Under such provisions, patients are entitled to equitable access to health
care services based on medical need, regardless of affluence, education, social
position, or race. Known as "Medicare," this social program has iconic status
in Canada and is unique among industrialized nations in banning any parallel
private insurance of publicly insured services.1
Proponents of the Canadian Medicare program have long argued that Canada's
unusually restrictive approach to private insurance ensures that the socioeconomic
elite remain in the public system.2-4 Because
they have high expectations of service and have influence beyond their numbers,
the elite are perceived to elevate the standard of service for all citizens.5 Critics respond by suggesting that the increased demands
of those most affluent are as likely to be excessive as appropriate, thereby
placing pressure on the public system by preferentially accessing an already
limited supply of specialty services.6-8
No study has formally evaluated how service patterns and perceptions
of care vary across socioeconomic strata in Canada for an acute life-threatening
disease. Our objective was to explore how Canadian patients from different
socioeconomic backgrounds perceive their medical care and to correlate patients'
backgrounds and care received with perceptions of health care access, quality,
Data were obtained from the Socio-Economic Status and Acute Myocardial
Infarction study (SESAMI). SESAMI is an ongoing prospective longitudinal observational
study of patients hospitalized with acute myocardial infarction (AMI) throughout
Ontario, Canada.9 The data elements collected
in SESAMI pertinent to this analysis include a 13-item patient-completed questionnaire
addressing risk factors for atherosclerosis as well as socioeconomic status
(SES) and ethnic characteristics and 30-day follow-up telephone interviews
addressing functional status, quality of life, utilization of specialized
cardiac services, medication use, and perceptions of health care access, satisfaction,
and quality. Mortality was identified through the Ontario Registered Persons
Data Base by data linkage using encrypted health card numbers. Participation
in SESAMI required written patient consent. SESAMI received research ethics
approval from each of the participating institutions.9
SESAMI recruited English-speaking Ontario residents who were admitted
for AMI through the emergency departments in 53 of 57 large-volume Ontario
hospitals (≥100 AMI admissions per year) between December 1, 1999, and
June 1, 2002. Trained nurses identified eligible AMI patients through chart
surveillance while patients were hospitalized in the coronary or intensive
care unit. The diagnosis of AMI was based on any 2 of 3 criteria: symptoms,
electrocardiographic (ECG) abnormalities, or elevated cardiac enzymes. Patients
were excluded if they were younger than 19 or older than 101 years, had no
valid Ontario health card number, or were transferred into the recruiting
site. Patients who died early (eg, within 24 hours), those with severe illness
(eg, receiving ventilatory support), persons with language barriers, and those
discharged or transferred early after presentation were ineligible for study
participation given their requirement to complete the self-administered baseline
survey at study entry.9
In total, 3335 of the 4474 consecutive eligible AMI patients approached
agreed to participate in baseline surveys and comprised the original SESAMI
cohort. Among these patients, 21.4% were ineligible for 30-day telephone interviews
due to death, recurrent hospitalization, or insufficient follow-up information,
leaving 2620 patients available for follow-up, of which 2256 patients consented
to 30-day telephone interviews (86% participation rate). Ineligible patients
(due to early death, recurrent hospitalization, or insufficient follow-up
information) were less affluent, older, and significantly more likely to have
preexisting heart disease than were those who participated in 30-day interviews.
However, the sociodemographic and clinical risk profiles of ineligible patients
were generally similar to those who were approached but refused participation
in the 30-day telephone follow-up interview. Moreover, socioeconomic risk
factor gradients were similar in relative magnitudes between ineligible and
eligible (consented and nonconsented) patients.
Socioeconomic and Ethnic/Racial Characteristics
SESAMI collected information on household annual income (7-level categorical
variable ranging from Can <$15 000 to ≥$80 000) and education
(5-level categorical variable ranging from incomplete high school to university
degree). In total, 94% of patients divulged their income, while 98% of participants
provided information related to education. To ensure similar sample sizes
across socioeconomic subgroups, both income and education data were each reaggregated
into 3-level categorical variables (income: ≤$29 999; $30 000-$59 999;
≥$60 000; education: incomplete high school; completed high school
or any incomplete postsecondary school education; degree in university, college,
or trade school). Similar aggregation levels for income and education have
been used elsewhere and shown to be important determinants of disease risk.10-14 Income
cutoffs also corresponded to Canadian federal and provincial year 2000 income
tax rate thresholds of $30 000 and $60 000.15 All
income levels reported herein are in Canadian dollars (Can $1 = US $1.34 as
of February 4, 2004).
Information on ethnicity was obtained through self-report. Patients
could select from 1 or more categories of a possible 13 ethnic/racial subgroups.10 For the purposes of this study, ethnic/racial data
were reaggregated a priori into 5 variables: white, black, South Asian, First
Nations (Canadian Native Indians), and other (eg, East Asian/Chinese). Each
of these categories has been shown to be associated with variations in disease
severity, treatment patterns, or both.16-18
Geographic and Hospital Characteristics
Previous studies by our group and others have demonstrated that geographic
and admitting hospital characteristics are important determinants of cardiac
specialty service use in Canada.19,20 Patients
were therefore categorized by urban vs rural place of residence and admitting
hospital characteristics (ie, onsite coronary angiography capacity). Urban-rural
information was obtained from patient postal codes using a Statistics Canada
Data regarding risk factors and preexisting heart disease were obtained
on all patients at study entry and were categorized by the presence or absence
of the following self-reported factors: diabetes mellitus, hypertension, hyperlipidemia,
current smoking, family history, and preexisting heart disease (and duration
if applicable). The reliability of self-reported risk factors was evaluated
through hospital chart audits for 1609 patients. Agreement levels were similar
across SES strata, ranging from 73% (hyperlipidemia) to 95% (diabetes).
Specialty Service Utilization
Patients were asked to report at 30 days on 3 measures of specialty
service use: (1) coronary angiography, (2) early referral for cardiac rehabilitation,
and (3) cardiology visits following discharge from the index AMI hospitalization.
We also examined post-AMI discharge visits to a primary care physician (general
practitioner/family physician) as a comparator. The reliability of self-reporting
for invasive procedures was evaluated through linkage to administrative data
for 1937 consecutive patients. Agreement levels were again similar across
SES strata, ranging from 74% (angiography) to 98% (coronary artery bypass
Patients were asked a series of questions with a 5-item response scale
from 1 (poor) to 5 (excellent) plus the option "don't know." Upon completion
of the interview, patients were asked to respond (yes, no, uncertain) to 2
supplementary questions about perceptions regarding privatization and willingness
to pay. The first applied to anyone willing to pay: "Based on the care you
received over the past 4 weeks, are you in favour of a two-tiered health care
system, whereby those who are willing to pay could have quicker access to
care and a wider selection of treatments and services, over and above standard
care?" The second was narrower and applied only to the respondent's willingness
to pay himself/herself: "Based on the care that you received over the past
4 weeks, would you be willing to pay for quicker access to services and a
wider choice of treatment and hospital options?" Because the questions were
added following study initiation, only 1815 of 2256 consecutive patients were
asked about their perceptions regarding privatization and willingness to pay.
The ethics review boards of the participating institutions were informed of
the supplemental questions. All but 1 hospital (consisting of 57 study patients)
consented to the additional question, leaving 1758 eligible patients to respond,
of whom 1684 (95.8%) did so.
We examined crude differences in baseline characteristics, specialty
service use, perceptions of care, and outcomes across income and education
categories using the Mantel-Haenszel χ2 test for trend for
categorical data and analysis of variance for continuous data. Because perceptions
of care were skewed per usual toward the positive extreme, the relationship
between SES and perceptions was examined for most satisfied (vs less so) and
least satisfied (vs more so). Multiple logistic regression techniques examined
for differences in the perception and utilization of specialty cardiac care
across SES, after adjusting for age, sex, ethnic/racial differences, cardiac
risk factors, preexisting coronary artery disease, onsite catheterization
capacity at the admitting hospital, and place of residence (urban vs rural),
using backward stepwise regression comparing –2 log likelihood ratios
between models. Multiple logistic regression models were also used to examine
for any interactions between SES, participation status, and clinical risk
factor profiles. Cox proportional hazard models examined the relationship
between SES and mortality at 1 year following the AMI, after adjusting for
each of the baseline characteristics described above, using stepwise regression.
For all analyses, income and education were examined as 3-level categorical
variables, with each SES variable adjusting for the presence of the other
in multivariate analyses. Diagnostic testing for collinearity revealed that
no explanatory variable had an associated variance inflation factor of greater
than 5 (maximum in our analysis was 1.88). Odds ratios were converted to relative
risks (RRs) using the method described by Zhang and Yu.22 Statistical
significance was defined as P<.05. SAS version
8.2 (SAS Institute, Cary, NC) was used for all analyses.
Baseline Characteristics and Survival
The median age of the study sample was 64 years; 30% were women. Table 1 compares the distribution of baseline
characteristics between SESAMI patients who consented and those who did not
consent to telephone follow-up. Consenting patients were younger, more affluent,
more educated, and less likely to have preexisting heart disease.
Less affluent patients were significantly older, more likely to be women,
more likely to be South Asian, reside in rural communities, and have diabetes,
hypertension, and preexisting heart disease (P<.001
for all comparisons) than were more affluent patients. Socioeconomic risk
factor gradients among study participants were most marked for diabetes (range,
30.9% to 16.7% from lowest to highest income tertile; P<.001), preexisting heart disease (range, 49.1% to 30.6% from lowest
to highest income tertile; P<.001), and hypertension
(range, 58.0% to 40.7% from lowest to highest income tertile; P<.001). The corresponding socioeconomic risk factor gradients among
eligible patients who refused participation in the telephone follow-up were
similar in relative magnitudes. There were no significant interactions between
SES and participation status in their associations with any of the risk factor
profiles examined (interaction terms, P>.20).
Crude mortality rates in the interval between 30 days and 1-year follow-up
were higher among patients with lower household incomes (5.1% vs 1.9% for
earnings ≤$29 999 vs earnings ≥$60 000, respectively; P = .001) and lower education (4.4% and 2.9% for those
with incomplete high school vs those with completed high school and postsecondary
degrees/diplomas, respectively; P = .07). After adjusting
for baseline characteristics, neither income (adjusted risk ratio, 1.25; 95%
confidence interval [CI], 0.68-2.31 for earnings ≤$29 999 vs ≥$60 000)
nor education (adjusted risk ratio, 0.88; 95% CI, 0.51-1.50 for incomplete
high school vs postsecondary degrees/diplomas) was significantly associated
with mortality at 1 year following hospitalization for AMI.
Provision of Specialty Cardiac Services
While the vast majority of patients who received interventions did so
during the index hospitalization regardless of their SES (88%), patients with
higher incomes and education levels were significantly more likely to have
been referred for coronary angiography (P<.001),
cardiac rehabilitation (P<.001), and to a cardiologist
(P = .04 for education, P<.001
for income) following discharge from AMI hospitalization. In contrast, general
practitioner follow-up did not vary by patient income or education (Figure 1 and Table 2).
After adjusting for baseline characteristics, education was a stronger
and more consistent determinant of specialty cardiac service use than was
income. Compared with patients with postsecondary degrees/diplomas, patients
who did not complete high school were less likely to receive any specialty
cardiac services by 30 days following AMI (Table 2). After adjusting for baseline income and other variables,
persons not completing high school education had significantly lower probabilities
of receiving coronary angiography and cardiac rehabilitation than individuals
who completed postsecondary education (Table 2).
Socioeconomic service gradients were similar in relative magnitudes
when confining the analysis to urban patients regardless of whether onsite
cardiac catheterization capacity was available at the admitting institution.
Perceptions of Cardiac Care
Table 3 illustrates the
univariate associations between SES and perceptions of care. After adjusting
for baseline demographic and clinical factors, income was the strongest predictor
of responses on the affordability of medications, while education was the
strongest determinant of perceptions of care (Table 4). Compared with higher income categories, patients earning
less than $30 000 per year were less likely to be able to afford all
necessary medications. Compared with patients who did not finish high school,
those with postsecondary degrees/diplomas were more likely to be extremely
dissatisfied with access to specialty care (adjusted RR, 2.02; 95% CI, 1.20-3.32),
with provider "skill, concern, and caring" (adjusted RR, 2.40; 95% CI, 0.91-6.13),
and with overall care (Table 4).
In total, 20% of AMI patients stated that they favored allowing private
care for anyone who was willing to pay. When asked about their own willingness
to pay, the proportion of those in favor of out-of-pocket payments for more
expedient or a wider selection of treatment or hospital services increased
marginally to 25%. Patients who were most satisfied with access to specialty
care (21.4% vs 28.0%, P = .007), with provider concern
(22.2% vs 26.7%, P = .05), and with the overall care
received (22.1% vs 25.9%, P = .09) were less willing
to pay for medical services compared with those with lesser degrees of satisfaction.
Perceptions regarding privatization and willingness to pay varied significantly
more widely across income than education (Figure 2). After adjusting for baseline factors including education,
cardiac risk factors, rural-urban status, and onsite procedural capacity,
patients with higher household incomes were significantly more likely to prefer
privatization of services (adjusted RR, 1.65; 95% CI, 1.24-2.14 for patients
earning ≥$60 000; adjusted RR, 1.25; 95% CI, 0.93-1.65 for patients
earning $30 000-$59 999), and acknowledged a greater willingness
to pay for faster service or more service choices (adjusted RR, 2.11; 95%
CI, 1.70-2.58 for patients with household incomes ≥$60 000; adjusted
RR, 1.50; 95% CI, 1.16-1.90 for patients with household incomes of $30 000-$59 999).
Preferences for private payment options were as marked for urban patients
admitted to hospitals with onsite procedural capacity as they were for urban
patients admitted to hospitals without, and persisted after adjusting for
We found significant socioeconomic differences in the provision and
perceptions of care among patients with AMI in Canada. Despite receiving more
intensive specialty cardiac services, patients in higher socioeconomic strata
were more dissatisfied with access to and quality of care and much more willing
to pay out-of-pocket for expedited services or for a wider array of treatment
options. In the latter respect, we found that one quarter of all AMI survivors
were willing to pay out-of-pocket for either expedited services or for a wider
array of treatment options, with proportions ranging from just over 15% for
persons with household incomes of less than $30 000 annually to more
than 30% for those with household incomes of $60 000 and above. While
overall satisfaction with care was high across all subgroups, those with highest
SES were more likely to be dissatisfied than patients of lower SES.
These findings suggest that Canadian restrictions on parallel private
insurance may serve to keep the upper-middle class "canaries in the coalmine,"
thereby providing a check on the amount of deterioration in the publicly funded
system that would be tolerated. However, the question may be raised as to
whether their advocacy truly enhances the overall system or is primarily self-serving.
A significant minority of these individuals are also willing to pay for services
outside the system. Absent a ban on private insurance, these persons may gain
even more advantages in consumption of health services. But it is also arguable
that these persons are competing successfully against other socioeconomic
groups for scarce resources in the public system and might just as well pay
privately for the unfair advantages they are deriving within the public system.
The argument is further illuminated by data on physician service utilization
from other countries. Van Doorslaer et al23 recently
reviewed 1990s survey data from Organisation for Economic Co-Operation and
Development nations and found that, after adjusting for age, sex, and indices
of morbidity, wealthier respondents visited specialists more often in 13 of
14 nations studied. In contrast, use of general practitioner services was
generally income-neutral after adjusting for need. All these nations except
the United States offered some form of national health service or universal
health insurance, and only Canada proscribes parallel or supplementary private
insurance for physician services. There was no evidence that the differentials
in service consumption were smaller in Canada, notwithstanding the variable
uptake of private insurance in other nations.
Historically, Canadian data suggest that the initiation of universal
health care coverage reduced socioeconomic disparities in consumption of health
services but never fully eliminated them.24 Our
study adds to a small but growing body of work demonstrating that access to
specialist services and procedures continues to vary with SES in Canada.14,19,25,26 For
example, our data suggest that patients who completed a postsecondary education
were almost twice as likely to access cardiac rehabilitation as those who
had not completed high school. The issue accordingly is not whether Medicare
has enhanced equity in access to health care, but whether Canada's uniquely
restrictive approach to private insurance is defensible and sustainable.
On the positive side of the ledger, our study demonstrates that only
a minority of patients were willing to pay for faster or more varied services.
Furthermore, only small numbers of patients were extremely dissatisfied with
access to specialists, waiting times, or the skill, caring, and concern of
clinicians. This may reflect the phenomenon that patients who have recently
accessed health services tend to be more positive than those who are awaiting
care or who have not themselves been helped by the health system in the recent
Our study has several important limitations. First, patients were required
to provide informed consent, patient enrollment was confined to large-volume
hospitals, and attrition of the initial sample following discharge from the
index AMI hospitalization may have biased our sample. However, the overall
consent rate for the original SESAMI cohort was excellent (75%)9;
86% of eligible patients consented to participate in 30-day follow-up interviews;
and socioeconomic risk factor gradients were similar between participants
and nonparticipants (either because they had refused participation or because
they were ineligible for telephone follow-up due to early death, recurrent
hospitalization, or insufficient follow-up information). Second, SESAMI was
restricted to Ontario, and the generalizability of our results to other Canadian
provinces is unknown. However, Ontario comprises one third of the nation's
population, and socioeconomic AMI–cardiac service gradients have been
demonstrated in other Canadian provinces.30 Finally,
information on clinical parameters such as infarct size or severity was not
known. However, the available clinical data suggest that patients with less
education or lower incomes would, if anything, have more serious infarcts
and a greater need for cardiac rehabilitation and secondary prevention.31
In conclusion, as evidenced by patients hospitalized for AMI, upper-income
and better-educated Canadians were less likely to be satisfied with access
to and quality of health care received, despite receiving more specialty cardiac
services than those in lower socioeconomic groups. In contrast, citizens in
the lower and middle tertiles of income and education received fewer specialty
services but were more satisfied with services and less interested in paying
for services privately. These findings speak to continuing tensions in the
financial framework for Canada's Medicare system. In turn, these tensions
are likely to shape continuing debate about the organization and finance of
the Canadian health care system in the years ahead.
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