Association between work shifts, occupational stress, and abdominal obesity in female workers in Southern Brazil.

Background: Night work and occupational stress contribute to weight gain and abdominal fat accumulation through behavioral and metabolic changes. This study investigated the relationship between occupational stress, work shifts, and abdominal obesity among female workers in Southern Brazil. Methods: This repeated cross-sectional study included two samples collected in 2017 and 2022, each comprising 400 female workers from two factories located in Southern Brazil. Abdominal obesity was measured by waist circumference (WC ≥ 88 cm), and occupational stress was assessed using the Job Stress Scale - short version. Data on demographic, socioeconomic, occupational, reproductive, and health variables were collected. Poisson regression with robust variance was used for multivariate analysis, stratified by occupational stress (absence vs. presence) and adjusted for potential confounders. Results: The workers' mean ages were 35.8 ± 9.0 years (2017) and 34.2 ± 9.9 years (2022). The prevalence of abdominal obesity was 45.1% (95% confidence interval [CI]; 40.2-50.0) in 2017 and 43.0% (95% CI, 38.1-47.9) in 2022, while occupational stress was observed in 22.9% (95% CI, 18.8-27.1) and 21.0% (95% CI, 17.0-25.0) of the workers, respectively. Among workers with occupational stress, nightshift workers were twice more likely to have abdominal obesity compared to daytime workers (2017; prevalence ratio [PR] = 2.23, 95% CI; 1.47-3.38, Conclusion: Occupational stress significantly modified the relationship between nighttime work and abdominal obesity. This study found a high prevalence of abdominal obesity, especially among female night shift workers, with no significant changes in prevalence rates between 2017 and 2022.