Increasing prevalence of asthma in UK primary care during the 1990s

To estimate recent prevalence trends of physician-diagnosed asthma in primary care in the UK, and to test the hypothesis that the asthma epidemic in the UK peaked in the mid-1990s and is currently declining.

A retrospective cohort of asthma patients was obtained from the General Practice Research Database (GPRD). From January 1990 to February 1999, asthmatics were followed up to death, censoring or mention of chronic obstructive pulmonary disease (COPD) in their clinical record. Prevalence rates of ever and managed asthma were obtained by sex, age and calendar year.

From 1990 to 1998, annual prevalence rates of managed physician-diagnosed asthma in women rose from 3.01% (95%CI 2.99-3.03) to 5.14% (95%CI 5.10-5.18), and in men from 3.44% (95%CI 3.41-3.46) to 5.06% (95 %CI 5.02-5.10) (P for trend <0.01 in both). In 1998, prevalence rates of managed asthma in children aged 5-14 affected 7.86% (95%CI 7.71-8.00) of girls and 10.30% (95%CI 10.15-10.47) of boys. Increasing prevalence rates in adult asthma (maximum 4.11% in 1998, 95%CI 4.03-4.19) and elderly asthma (maximum 3.37% in 1998, 95%CI 3.29-3.46) were observed as well in 1998. The study shows that the burden of asthma in UK primary care during the 1990s was still increasing.