INCOME LEVEL AND ASTHMA PREVALENCE AND CARE PATTERNS

Manitoba has a universally accessible health-care system that records physician contacts and hospitalizations in such a way that they can be ascribed to individuals. We examined the prevalence of physician diag nosed asthma, bronchitis, and airways obstruction (total respiratory m orbidity [TRM]) in Winnipeg in 1988 and 1992, using place of residence to divide people into quintiles according to average family income. P hysician office visits, hospitalizations, and consultation referrals w ere each examined. Three age groups: 0 to 14 yr, 15 to 34 yr, and grea ter than or equal to 35 yr were studied. The prevalence of TRM was gre ater in low- than in high-income quintiles. Asthma prevalence was unre lated to income in the younger age groups; in the older group asthma w as more common in low-income groups, but was less strongly related to income than was TRM. Asthma prevalence increased over the years studie d, but the increase was not related to income level. There was some ev idence of income-related diagnostic bias in that low-income patients w ere more likely to be labeled with a related diagnosis in addition to asthma than were high-income patients. Low-income patients had more ph ysician contacts than did high-income patients. In terms of physician office visits, care continuity did not differ among income quintiles. Low-income quintiles had more hospitalizations than did high-income qu intiles, and differences were larger than could be accounted for by di agnostic bias; asthma was probably more severe in low-income quintiles . High-income quintiles had more consultation referrals than did low-i ncome quintiles.