Evening chronotypes have the increased odds for bronchial asthma and nocturnal asthma

Earlier studies have found associations of chronotypes with a range of health-related factors. In the light of these findings, the behavioral trait of eveningness in particular associates with determinants that might have a negative impact on health. In this study, based on a random sample of population aged 25-74 years living in five large geographical areas in Finland (N = 6089), we tested whether the evening chronotypes have the increased odds for respiratory symptoms and diseases. As a result, after controlling for socio-demographic and lifestyle factors, evening-types had wheezy breathing without respiratory infection, a diagnosed or treated bronchial asthma, awoken in shortness of breath, awoken in heavy to breath, wheezy breathing with dyspnea, wheezy breathing as such and medication for asthma more often than morning-types (odds ratios (ORs) of 1.5-1.9) and intermediate-types (ORs of 1.3-1.6). In addition, evening-types had current medication for asthma, and awoken in coughing more often (OR = 1.5 and OR = 1.4, respectively) than morning-types. Evening-types did not have a diagnosed or treated chronic bronchitis more frequently than others. Our results suggest that the behavioral trait of eveningness associates with the increased odds for the bronchial asthma and nocturnal asthma in particular.