Objects: The aim of our study was to investigate whether major depressive disorder (MDD) increased the risk of hypertension using propensity score matching (PSM) in patients with MDD in Taiwan. Methods: In this study, we recruited all samples from a random sample sub-dataset of one million insured individuals from 2005. A total of 743,114 outpatients were included in our study. We used PSM (nearest neighbor matching) stratified by age, hospital level, insurance amount, and Charlson Comorbidity Index score. Results: The hazard ratio (HR) of hypertension was significantly greater in the male MDD outpatients (HR = 1.116, P = 0.004) than in the female MDD outpatients (HR = 0.93, P = 0.02). Using PSM, we selected 27,988 outpatients with hypertension and 27,988 outpatients without hypertension for a nested case-control study. In this analysis, female outpatients with MDD (relative risk = 0.852) had lower risks of hypertension. Male outpatients without/with MDD (relative risk = 1.987/3.018) showed a synergistic interaction with gender in which male patients had a higher risk of hypertension in a multiplicative model. Furthermore, MDD appeared to have an interaction effect with gender (HR = 1.82, P < 0.001) in the proportional hazards model analysis. Antidepressant use also increased the risk of hypertension (HR = 1.16, P < 0.001). Conclusions: There was gender disparity in the risk of hypertension in subjects with MDD. MDD outpatients who used antidepressants had a higher risk of suffering from hypertension. A large-scale, population-based study is warranted to generalize these results in the future.
Keywords: National Health Insurance Database; hypertension; major depressive disorder (MDD); propensity score matching (PSM); risk factors.