Job strain and binge eating among Brazilian workers participating in the ELSA-Brasil study: does BMI matter?

OBJECTIVE To assess the association between job strain and binge eating as well as the effect-modifying influence of body mass index (BMI) on this association. METHODS A total of 11,951 active civil servants from the multicenter Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) was included in this cross-sectional analysis. Job strain was assessed using the Demand-Control-Support Questionnaire. Binge eating was defined as eating a large amount of food with a sense of lack of control over what and how much is eaten in less than 2 hours at least twice a week. Multiple logistic regression was used to determine the association between binge eating and job strain as well as its interaction with BMI. RESULTS After adjustment, and using low-strain job as the reference category, binge eating was associated with high-strain job (high demand/low control: odds ratio [OR]=1.58, 95% confidence interval [CI] 1.26-1.98), active job (high demand/high control: OR=1.35, 95% CI 1.07-1.70), and passive job (low demand/low control: OR=1.24, 95% CI 1.01-1.53). Psychological job demands were positively associated with binge eating (OR=1.04, 95% CI 1.01-1.07), while greater job control and social support at work were each inversely associated with binge eating (OR=0.95, 95% CI 0.92-0.97 and OR=0.96, 95% CI 0.94-0.98, respectively). BMI modified the association between job strain and binge eating: Heavier psychological job demands were associated with higher odds of binge eating among obese participants, while a stronger inverse association between job control and binge eating was seen among slimmer participants. CONCLUSIONS Job strain increases the odds of binge eating and this association is modified by BMI.