Hassan M, et al. - In this systematic review of 14 reports including 2,297 patients, researchers assessed the prevalence as well as determinants of nonadherence in adult patients with severe asthma. They searched Embase and Pubmed to identify the relevant studies. For inclusion, the studies were required to have utilized objective methods for monitoring adherence and clear definition of the level of asthma severity. This review did not include predominantly pediatric studies or studies of less severe asthma. Nonadherence to treatment was identified as a common problem in the management of patients with severe asthma. As per the findings of the meta-analysis of adherence predictors, male sex was found to be related to adherence with an odds ratio of 2.25 and higher asthma quality of life questionnaire scores with a mean difference 0.47 points in adherent patients. Older age, more knowledge about asthma, simpler medication schedules were identified as other predictors, from single studies, demonstrating a significant relation to adherence.