The rising prevalence of asthma in young Melbourne adults is associated with improvement in treatment

Abstract

Background: Asthma is a common source of morbidity and is now recognized as a national health priority in Australia. Although a number of epidemiologic studies have been conducted in Australia to determine the prevalence of asthma in adults, it is unclear whether the prevalence is changing.

Objectives: To determine the prevalence in 1998 of self-reported asthma and respiratory symptoms among young adults and changes in prevalence between 1990 and 1999.

Methods: Cross-sectional postal survey to 4,455 young adults (aged 20 to 44 years) randomly selected from the electoral rolls of the inner southeastern suburbs of metropolitan Melbourne. The survey instrument was the validated European Community Respiratory Health Survey screening questionnaire, which gathered data on self-reported respiratory symptoms, including whether asthma had been diagnosed. Identically worded questions from similar surveys conducted in 1990, 1992, and 1999 were used to compare changes in prevalence.

Results: A response rate of 72% was achieved in 1998 after three mailings and telephone followup. Forty-two percent reported nasal allergies, 26% wheezed within the past 12 months, and 20% ever had asthma. The prevalence of doctor-diagnosed asthma was 18%, whereas 10% reported using asthma medications within the past 12 months. Nine percent of respondents reported an asthma attack within the past 12 months. The prevalence of having ever had asthma, doctor-diagnosed asthma, and using asthma medications had increased significantly since 1990. However, the prevalence of respiratory symptoms did not significantly change over this time.

Conclusions: The prevalence of asthma is likely to be rising, but the symptoms of asthma are being better managed in young Melbourne adults.