Asthma and its comorbidities in middle-aged and older adults

Background: 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.
Methods: 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.
Results: 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.
Conclusion: 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.