Metabolic syndrome and depression: evidence from a cross-sectional study of real-world data in Japan

BACKGROUND: Both metabolic syndrome (MetS) and depression are high priority health problems, especially for working age. Numerous studies have explored the link between metabolic syndrome and depression; however, not all of them have consistently demonstrated an association. The objective of this study was to determine whether there is an association between MetS and depression by analyzing extensive real-world data (RWD). METHODS: Our data was drawn from insurance claims and health checkups of local government officials across all prefectures in Japan except for Tokyo in the 2019 fiscal year. According to the number of months with diagnosis of depression and prescription of antidepressants, the study participants were classified into the following categories: Certainly not Depression (CN), Possibly not Depression (PN), Possible Depression (PD), and Certain Depression (CD). Associations between MetS and its components-visceral obesity, hypertension, hyperlipidemia, and diabetes- and these categories of depression were analyzed by logistic regression. RESULTS: The depression categories of the 130,059 participants were as follows: CN 85.2%; PN 6.9%; PD 3.9%; and CD 4.1%. For men, the adjusted odds ratio (AOR) for MetS were PN 0.94 (95% CI: 0.86-1.02), PD 1.31 (1.19-1.43), and CD 1.63 (1.50-1.76), with reference to CN. For women, AOR of MetS were PN 1.10 (0.91-1.32), PD 1.54 (1.24-1.91), and CD 2.24 (1.81-2.78). Among the MetS components, visceral obesity, hyperlipidemia, and diabetes were significantly associated with depression categories. CONCLUSIONS: In this study, we found a significant association between MetS and depression, this association being similar to that previously reported. Our findings provide robust evidence for linkage between MetS and depression, suggesting that analysis of RWD is useful for providing concrete evidence.