Prevalence and correlates of asthma in the elderly

Abstract

The prevalence of asthma has been increasing for the past two decades. Bronchial asthma in the elderly has not received as much attention as asthma among children and adults. Recent studies have suggested that asthma is not an uncommon condition in the elderly. Our objectives were to determine the prevalence and correlates of asthma and asthma symptoms in the West Texas elderly population. Texas Tech 5000 is a telephone-administered longitudinal health study of the elderly age 65 and older residing in the 108 counties that comprise West Texas. In wave 3 of the survey a total of 3392 subjects participated with a response rate of 89%. Subjects with emphysema were excluded and the analysis was restricted to subjects with non-Hispanic white or Hispanic race or ethnicity ( n = 3021). The sample data were weighted using U.S. Census 2000 West Texas population. The prevalence and predictors of current asthma, probable asthma and wheezing were estimated using survey logistic regression analyses. Health-related quality of life (QoL) was determined using a 15-item mini-Asthma QoL scale and a 12-item SF-12 scale. The prevalence of current asthma was 6.3%, whereas 19.7% reported having wheezing in the previous 12 months. The prevalence of current asthma was lowest among Hispanic Americans (4.1%, 95% CI = 2.0, 6.2). The most common nocturnal asthma symptoms reported were cough and shortness of breath. A significant impairment in QoL (especially for rural residents) was observed for the environmental stimuli domain among subjects with asthma. Significant physical impairment (lower PCS score on the SF-12 scale) was also observed for subjects with current asthma ( P < 0.05). In the multiple logistic regression analysis, Hispanic ethnicity (adjusted odds ratio AOR = 0.46, 95% confidence interval CI = 0.23, 0.91), hay fever (AOR = 3.56, 95% CI = 2.56, 4.95), low income (AOR = 1.84, 95% CI = 1.04, 3.27), history of smoking cigarettes (AOR = 1.48, 95% CI = 1.03, 2.14), two or more ER visits in the previous 12 months (AOR = 2.2, 95% CI = 1.16, 4.17), and severe pain (AOR = 1.55, 95% CI = 1.05, 2.28) were independent risk factors for current asthma. This study identified several risk factors associated with current asthma. Given that older individuals spend most of their time indoors, routine environmental assessment should be considered as part of their asthma management plan.