Asthma and its comorbidities in middle-aged and older adults; the Rotterdam Study

Little is known on the prevalence and characteristics of asthma in middle-aged and older adults, since previous studies mainly focused on children and young adults. Therefore, the aim was to investigate the prevalence of physician-diagnosed asthma and its comorbidities, in a population-based cohort of adults 45 years of age and over.

We identified participants with physician-diagnosed asthma in the Rotterdam Study; a prospective population-based cohort in the Netherlands. Pulmonary function measurements and comorbidities of the asthma cases were assessed at baseline and compared to those of the general population.

Out of 14,621 participants (mean age 65.5 years; 59% women), 524 subjects (31.5%males) had physician-diagnosed asthma at study entry, implicating an asthma prevalence of 3.6% [95% Confidence Interval (CI) 3.3%-3.9%] (2.8% in males and 4.2% in females). Asthmatic subjects had a significantly higher prevalence of obesity and depressive symptoms (Odds Ratio [OR]: 2,02 [95% CI 1,66-2,47] and [OR]: 2,01 [95% CI 1,52-2,66] respectively). Longer duration of asthma and current smoking were associated with lower lung function in asthmatic subjects.

Four percent of middle-aged and older adults have physician-diagnosed asthma. These adult asthmatics suffer more frequently from obesity and depression than subjects without obstructive lung disease.