Shift work, job strain, and metabolic syndrome: Cross‐sectional analysis of ELSA‐Brasil

Background Shift work and psychosocial stressors may contribute to higher metabolic syndrome (MetS) incidence. Few studies investigated whether the presence of both factors simultaneously has a synergic effect on risk of MetS. Methods This cross‐sectional analysis used baseline data (2008‐2010) for 10 960 current workers from ELSA‐Brasil. Multiple logistic regression was used to estimate independent associations between shift work and job strain and MetS. An interaction between these factors was tested by including a multiplicative term in the final model. Results Exposure to three‐shifts a week (that is, three 12 h shifts of work followed by 36 h of rest) and high job‐strain were independently associated with greater risk of MetS. We found no indication (P > 0.05) of interaction between working in shifts and job strain on MetS. Conclusions Efforts to reduce job strain and shift work should be considered as part of a primary prevention strategy to reduce the risk of MetS.