['To examine the incidence of asthma in adult patients with major depressive disorder (MDD).', 'From the National Health Insurance database of Taiwan, we identified 30 169 adult patients who were newly diagnosed with MDD between 2000 and 2010. Individuals without depression were randomly selected four times and frequency matched for sex, age and year of diagnosis. Both cohorts were followed-up for the occurrence of asthma up to the end of 2011. Adjusted hazard ratios (aHRs) of asthma were estimated using the Cox proportional hazards method.', 'The overall incidence of asthma was 1.91-fold higher in the MDD cohort than in the non-depression cohort (7.55 v. 3.96 per 1000 person-years), with an aHR of 1.66 (95% confidence interval (CI) 1.55-1.78). In both cohorts, the incidence of asthma was higher in patients and controls who were female, aged, with comorbidities and users of aspirin or beta-adrenergic receptor blockers. No significant difference was observed in the occurrence of asthma between patients with MDD treated with selective serotonin reuptake inhibitors (SSRIs) and those treated with non-SSRIs (SSRIs to non-SSRIs aHR = 1.03, 95% CI 0.91-1.17).'] Is major depressive disorder associated with subsequent adult-onset asthma : a population-based cohort study?