Abstract
BACKGROUND: This study evaluated the association between psychological distress and development of type 2 diabetes (T2D) among male individuals in the workplace. METHODS: This observational cohort study enrolled 6,326 male participants aged 18 - 65 years (mean age 47.4 ± 9.5 years, body mass index 23.4 ± 3.4 kg/m(2), hemoglobin A1c 5.5±0.3%), who received annual health checkups from April 2016 to March 2017. Those who had a hemoglobin A1c level ≥ 6.5%, previous history of diabetes, or used diabetes medication were excluded from the analysis. Psychological distress was measured using the Brief Job Stress Questionnaire. Multivariate Cox proportional hazard regression models were used to estimate the development of T2D in relation to psychological distress and stress-related symptoms. The calculated hazard ratio (aHR) was adjusted for age, body mass index, and hemoglobin A1c level. RESULTS: During a mean follow-up period of 1.9 years, the incidence rate of new-onset T2D was 2.0%. Baseline psychological parameters did not differ between participants with or without new-onset T2D. Depression was associated with an increased risk of T2D (aHR = 1.54, 95% confidence interval (CI): 1.07 - 2.22), whereas vigor, irritation, fatigue, and anxiety were not. Moreover, inability to handle work (aHR = 2.18, 95% CI: 1.14 - 4.19), sadness (aHR = 1.93, 95% CI: 1.14 - 3.26), headache (aHR = 1.98, 95% CI: 1.18 - 3.34), shoulder stiffness (aHR = 1.56, 95% CI: 1.10 - 2.23), and constipation/diarrhea (aHR = 1.71, 95% CI: 1.04 - 2.80) were associated with T2D incidence. CONCLUSIONS: Depression and stress-related symptoms were associated with an increased risk of T2D. Industrial physicians and health care providers should evaluate these factors during health checkups to lower the T2D incidence in this population.