Chest
Volume 124, Issue 2, August 2003, Pages 438-448
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Clinical Investigations
ASTHMA
Stabilization of an Increasing Trend in Physician-Diagnosed Asthma Prevalence in Saskatchewan, 1991 to 1998*

https://doi.org/10.1378/chest.124.2.438Get rights and content

Objectives

To determine the prevalence of asthma, bronchitis, and COPD using the physician services database of the Saskatchewan Health Department from 1991 to 1998.

Design

Descriptive population-based study.

Setting

The Province of Saskatchewan, Canada.

Participants

Residents of Saskatchewan covered by universal health care in the province.

Results

In all age groups, asthma prevalence increased between 1991 and 1995 and either was stable or declined between 1996 and 1998. Preschool children had the highest asthma prevalence during the study period, followed by children aged 5 to 14 years, young adults aged 15 to 34 years, and adults aged 35 to 64 years. Children aged 0 to 4 years and adults aged 35 to 64 years in the Registered Indian population had greater asthma prevalence than persons in other urban or rural populations during the study period. Asthma prevalence rates in rural populations were less than or similar to the rates of urban populations in all age groups during the study period. The prevalence of bronchitis was greater in the Registered Indian population than in urban and rural populations in all age groups throughout the study period. When persons who had visited a physician for bronchitis were excluded from the prevalence calculation, the original increases seen in asthma prevalence among very young children and older adults of Registered Indian origin disappeared, with the urban population having greater asthma prevalence in all age groups. In the Registered Indian population, adults aged 35 to 64 years had almost twofold increases in the prevalence of COPD in comparison to other Saskatchewan populations.

Conclusions

Asthma prevalence, which had been on the increase in the 1980s and early 1990s, was either stable or declining during the latter part of 1990s in Saskatchewan. Preschool children and older adults from the Registered Indian population had greater asthma prevalence than did those from other Saskatchewan populations. Asthma prevalence among the rural populations was either similar or lower in comparison to the rates for the urban populations in all age groups during the study period. Further research is required to elucidate the findings in this study.

Section snippets

Saskatchewan Population

As reported in the 1996 census, the population of Saskatchewan was composed of 976,615 persons, which included people of European origin (81.7%), aboriginal origin (11.4%), and other single (2.3%) and multiple (4.7%) origins.1920 The Registered Indians of Saskatchewan are of aboriginal origin and have registered under section 6 of the Indian Act with the Federal Government of Canada. This population is made up of mainly Cree and Chipewyan origins, and a small number of Saulteaux, Assinibione,

Asthma Prevalence

As shown in Figure 1, asthma prevalence rates were highest in preschool children aged 0 to 4 years during the study period, followed by school-going children, young adults, and older adults. This pattern was consistent throughout the study period. There was a rapid increase in asthma prevalence rates from 1991 to 1995, and a steady increase from 1996 to 1998 among preschool children as well as young adults and older adults. In school-going children aged 5 to 14 years, an increase was observed

Discussion

In our study, we used the physician services database of the Saskatchewan Health Departments to estimate the period prevalence of asthma from 1991 to 1998. The period prevalence estimates of 8.1% in preschool children (0 to 4 years) and 5.9% in school-going children (5 to 14 years) in 1998 from our study are consistent with those of a Canadian cross-sectional study,1 which reported a lifetime asthma prevalence of 10% among children aged 0 to 14 years of age.

In our previous report,18 asthma

ACKNOWLEDGMENT

The authors thank Winanne Downey of Research Services, Population Health Branch, Saskatchewan Department of Health for assistance with abstracting the data and reviewing the manuscript.

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    The research was supported by a grant from the Health Services and Utilization Research Commission, Saskatchewan, Canada.

    This study is based in part on nonidentifiable data provided by the Saskatchewan Department of Heath. The interpretations and conclusions contained herein do not necessarily represent those of the Government of Saskatchewan or the Saskatchewan Department of Health.

    Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (e-mail: [email protected]).

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