Abstract
OBJECTIVES: Psychosocial stress is a potential risk factor for type 2 diabetes (T2D); however, the influence of the timing of stress exposure remains uncertain. We examined the prospective associations of baseline, cumulative average, and recent psychosocial stress with the risk of incident T2D in middle-aged adults. METHODS: We analyzed data from 7,880 participants aged 40-64 years without T2D at baseline. Psychosocial stress was assessed repeatedly using the Psychosocial Well-Being Index-Short Form. Incidence rate ratios (IRRs) and 95% confidence intervals (CIs) were estimated using modified Poisson regression models with robust error estimators. RESULTS: A total of 437 T2D cases occurred over 47,621 person-years. While baseline stress showed a non-significant association, both cumulative and recent stress demonstrated positive associations with T2D risk. Recent stress exhibited the strongest association in both male (stress vs. healthy group: IRR, 2.23; 95% CI, 1.41 to 3.52; highest [T3] vs. lowest tertile [T1]: IRR, 1.50; 95% CI, 1.07 to 2.10) and female (stress vs. healthy group: IRR, 1.72; 95% CI, 1.11 to 2.66; T3 vs. T1: IRR, 1.73; 95% CI, 1.26 to 2.37). These associations were more pronounced among participants with abdominal obesity, showing a significant positive linear trend (Bonferroni-corrected threshold, p=0.003). CONCLUSIONS: Recent psychosocial stress was associated with an increased incidence of T2D, underscoring the importance of integrating psychosocial factors into diabetes prevention strategies, particularly for individuals with abdominal obesity.