Trends in rates of admission to hospital and death from asthma among children and young adults in Canada during the 1980s

Abstract

OBJECTIVE: To update reports of increases in the rates of admission to hospital and death from asthma among children and young adults in Canada during the 1970s by examining data for the 1980s. DESIGN: Age-standardized rates were calculated from data for people less than 35 years of age at the time of death from asthma, bronchitis or other respiratory conditions (from 1980 through 1989) and at the time of admission to hospital for treatment of these diseases (from 1980 through 1988). Standardized mortality ratios were calculated with the death rate for Canada as the expected rate. SETTING: Data for all of Canada were examined by sex, age group and province. RESULTS: In contrast to sharp increases in the rate of death from asthma observed from 1970 through the early 1980s among Canadians less than 35 years of age, the rate showed no net change between 1980 and 1989; on average, there were 58 deaths in this age group annually. During the decade, the rates of death from asthma were three times higher in Saskatchewan and Alberta than in Newfoundland. The national rate of hospital admission/separation for asthma, however, increased greatly, though changes in the rate varied by province. Increases of over 90% were observed in Prince Edward Island and New Brunswick, whereas little overall change occurred in Newfoundland, Manitoba and Saskatchewan. The rate of hospital admission/separation for asthma was highest in Prince Edward Island and lowest in Manitoba and British Columbia. Although the rates of hospital admission/separation for asthma among boys aged less than 15 years of age were consistently 50% higher than those among girls of that age, the rate among people aged 15 through 34 years was twice as high among females as males. A slight decrease in the rates of death from respiratory conditions other than asthma was observed, together with a steady, fairly substantial decline in the rates of hospital admission/separation for these conditions. CONCLUSIONS: Whether there is any relation between increases in rates of admission to hospital for asthma and trends in the rates of death from asthma during the decade will require further study.