Early menarche and adult major depressive disorder among Japanese women: The role of childhood traumatic experience and socioeconomic conditions in young adulthood.

Aim: The aim of this study is to examine the long-term impact of early menarche with adult depression, and to assess whether this association was explained by childhood traumatic experience and socioeconomic condition in early adulthood.

Methods: The data were derived from World Mental Health Survey Japan Second, a cross-sectional survey conducted among Japanese community residents between 2013 and 2015. We used the data of female respondents aged 20-75 years ( = 1171). Hazard ratio (HR) of the onset of major depression up to 40 years was calculated for an early-menarche group and a non-early-menarche group, respectively. Kaplan-Meier curve and log-rank statistics were used to examine the difference in failure. Cox proportional hazard models were administered for the association of major depression with early-menarche and early-life psychosocial factors.

Results: Risk for major depressive disorders were three to four times higher in an early-menarche group, and the differences in survival functions were significant ( < 0.001). HR of early menarche was 2.79 (95% CI = 1.29-6.02), and was slightly changed when childhood traumatic experience and socioeconomic conditions in young adulthood were added in the model (HR = 2.88, 95% CI = 1.30-6.38; HR = 3.19, 95% CI = 1.41-7.21).

Conclusion: Early menarche was significantly associated with increased risk for depression by the age of 40 years. Childhood trauma and socioeconomic hardship in early adulthood did not account for the association. Both physical and psychosocial risk factors in early life need to be addressed for preventing women's depression.