Trends in asthma prevalence: the Bogalusa Heart Study.

BACKGROUND

Epidemiologic surveys from different parts of the developed world are showing increases in asthma prevalence; the causes are not known.

OBJECTIVE

To describe trends in prevalence of childhood asthma measured across serial cross-sectional surveys of the school age population of Bogalusa, Louisiana.

METHODS

The Bogalusa Heart Study is a long-term epidemiologic study of risk factors for cardiovascular disease in children in a stable, semirural, biracial community. Part of the examination includes a parent-completed health history questionnaire. The item, "Does your child have or has your child had in the past...asthma?" was included in the 1983-5, 1987-8, and 1992-4 surveys. Data analysis was restricted to subjects aged 5 to 17 years.

RESULTS

Three thousand two hundred seventy-six subjects participated in 1983-5, 3256 in 1987-8, and 3128 in 1992-4. Reported asthma prevalence increased from 9.2% to 15.9% between 1983-5 and 1992-4. Maternal smoking was associated with asthma in all three surveys. Young age and African American ethnicity were associated with asthma only in the 1992-4 survey.

CONCLUSIONS

The prevalence of asthma among the school age population of Bogalusa, Louisiana increased by 73% between the 1983-5 and the 1992-4 surveys. Whether the increase in asthma prevalence represents an increase in disease presence or an increase in disease recognition cannot be determined from these data.