Exposure to shift work as a risk factor for diabetes

Using telephone survey data from 1111 retired older adults (≥65 years; 634 male, 477 female), we tested the hypothesis that exposure to shift work might result in increased self-reported diabetes. Five shift work exposure bins were considered: 0 years, 1-7 years, 8-14 years, 15-20 years, and >20 years. Shift work exposed groups showed an increased proportion of self-reported diabetes (χ(2) = 22.32, p < 0.001), with odds ratios (ORs) of about 2 when compared to the 0-year group. The effect remained significant after adjusting for gender and body mass index (BMI) (OR ≥ 1.4; χ(2) = 10.78, p < 0.05). There was a significant shift work exposure effect on BMI (χ(2) = 80.70, p < 0.001) but no significant gender effect (χ(2) = 0.37, p > 0.50).