RT Journal Article SR Electronic T1 Adult asthma increases dementia risk: a nationwide cohort study JF Journal of Epidemiology and Community Health JO J Epidemiol Community Health FD BMJ Publishing Group Ltd SP 123 OP 128 DO 10.1136/jech-2014-204445 VO 69 IS 2 A1 Yi-Hao Peng A1 Biing-Ru Wu A1 Ching-Hua Su A1 Wei-Chih Liao A1 Chih-Hsin Muo A1 Te-Chun Hsia A1 Chia-Hung Kao YR 2015 UL http://jech.bmj.com/content/69/2/123.abstract AB Background Studies on the association between adult asthma and dementia are few. We investigated the risk of dementia in patients diagnosed with adult asthma compared with that of people without asthma who were age and sex matched to the study patients. Methods We used data from the National Health Insurance Research Database. A total of 12 771 patients with newly diagnosed asthma between 2001 and 2003 were evaluated and 51 084 people without asthma were used as the comparison cohort. Cox proportional hazard regression analysis was used to measure the HR of dementia for the asthmatic cohort, compared with that of the non-asthmatic cohort. Results The HR of dementia was 1.27 (95% confidence interval (CI) 1.15 to 1.41) for the asthmatic cohort, compared with the non-asthmatic cohort after adjusting for age, sex, comorbidities, annual outpatient department visits and medicine used. The HR of dementia development increased substantially as frequency of asthma exacerbation and hospitalisation increased. Conclusions This nationwide cohort study suggests that the risk of dementia development is significantly increased in patients with asthma compared with that of the general population. In addition, dementia risk increases substantially with asthma exacerbation and hospitalisation frequency increases.