Mentally tiring work and type 2 diabetes in women: A 22-year follow-up study

Hypothesis: Previous work suggested no or inconsistent associations between components of work-related stress and type 2 diabetes risk, but suggested sex-specific differences should be further investigated, as women potentially had higher risks. Methods: We analyzed data from 73 517 women, mostly teachers, from the E3N cohort study followed for 22 years (1992–2014), to study the association between mentally tiring work, used as a proxy of job demands, and type 2 diabetes risk. Univariate and multivariable Cox regression models were used to estimate hazard ratios and 95% confidence intervals. Results: A total of 4187 incident cases of type 2 diabetes cases were observed. There was a higher type 2 diabetes risk for women with a ‘Very mentally tiring work’ when compared to women with ‘Little or not mentally tiring work’ (HR = 1.21 (1.09–1.35)). This association was independent of unhealthy lifestyle and traditional metabolic factors. An interaction between mentally tiring work and BMI was detected (P < 0.0001), with a stronger association being observed in non-overweight women, HR = 1.26 (1.08–1.47) vs HR = 1.14 (0.98, 1.32), in overweight women. Conclusions: We observed an increased risk of type 2 diabetes associated with mentally tiring work, used as a proxy of job demands. These observational results suggest the importance of taking into consideration the potential long-term metabolic impact of work-related stress for women working in a demanding environment. Increased support for such women should be investigated in intervention studies.