Association between asthma and dry eye disease: a meta-analysis based on observational studies

ObjectiveThis study aimed to systematically review the relationship between dry eye disease (DED) and asthma based on published population-based studies.Data sourcesPubMed, EMBASE and ISI Web of Science from their inception were searched up to October 2019.Study selectionObservational studies addressing the association between asthma and DED will be eligible.Data extraction and synthesisTwo reviewers independently conducted the data extraction and quality assessment. We used a random-effects model for all analyses. Subgroup analysis according to ethnicity was performed to test the influence of ethnicity on the association.Main outcomes and measuresSix independent studies (a total of 45 215 patients with asthma and 232 864 control subjects) were included in this review and had an average of seven stars by the Newcastle-Ottawa Scale. Our current findings suggest that the prevalence of DED was higher in the asthma group than in the control group (Z=7.42, p