Association of Age at Menarche With Depression in Adulthood in NHANES 2015-2023: A Cross-Sectional Study.

PURPOSE: The primary objective of this study is to elucidate the role of age at menarche in depression in adulthood and explore the implications of this association. METHODS: We conducted a study involving 9,826 adult female participants from the National Health and Nutrition Examination Survey (NHANES) between 2015 and August 2023. Age at menarche was categorized as early (<12 years), normal (12-14 years), or late (≥15 years). Depression was assessed using the 9-item Patient Health Questionnaire (PHQ-9) and clinical diagnoses. Logistic regression and restricted cubic spline analyses were performed to address the study objectives. In addition, subgroup analyses were conducted based on demographic, lifestyle, and clinical characteristics. RESULTS: The depression group had a significantly higher proportion of young adults (aged 18-30 years) compared to the nondepression group (26.46% vs. 20.52%, p < .001). Conversely, the nondepression group included a greater proportion of older adults (over 60 years) than the depression group (29.53% vs. 23.98%, p < .001). After comprehensive adjustments, early menarche was significantly associated with increased depression risk (adjusted odds ratio [aOR] = 1.224, 95% confidence interval [CI]: 1.003-1.493, p = .047). Restricted cubic spline analyses revealed an L-shaped nonlinear pattern (p for nonlinearity = 0.006), with optimal age at menarche around 12 years. Subgroup analyses confirmed consistent associations without significant interactions. DISCUSSION: Early menarche is linked to increased depression risk, especially among women aged 18-30 years. Menarche at 12 years may serve as a key point for early intervention to prevent depression in young women.