[Hyperuricemia in shift workers: a cross-sectional study in a spanish chemical factory]

There is no clear consensus over the findings of research into shift work and cardiovascular risk factors, such as those present in the metabolic syndrome (MetS). This is further confounded by the varying definitions of MetS and shift work. Our objective was to learn about the link between shift work, lifestyles and cardiovascular health in chemical factory workers.

Cross-sectional analytical study, carried out 2018-2019; data obtained from annual occupational health check-ups. 515 workers chosen, with a 1:3 ratio (shifts/no shifts). Variables collected: MetS, arterial hypertension, obesity, abdominal adiposity and biochemical alterations (glucose, total cholesterol, HDL cholesterol, triglycerides and uric acid). Explanatory variables: age, gender, tobacco consumption, physical activity and shift work. Besides the usual descriptions, both non-adjusted and adjusted bivariate logistic regression were performed, producing Odds Ratio (OR) values with 95% CI.

The non-adjusted logistic regression showed that shift workers performed less physical activity (OR=0.22; 95% CI=0.14-0.35; p<0.001) and had lower HDL cholesterol levels (OR=2.1; 95% CI=1.2-3.8; p<0.05), plus a higher rate of hypertriglyceridemia (OR=2.05; 95% CI=1.3-3.2; p<0.01) and hyperuricemia (OR=2.7; 95% CI=0.9-2.7; p<0.001). In the logistic regression adjusted for age, gender, tobacco consumption, physical activity and shift work only the prevalence of hyperuricemia was higher in shift workers (OR=2.25; 95% CI=1.1-4.6; p<0.05), as well as with less moderate/high physical activity (OR=0.19; 95% CI=0.12-0.31; p<0.001).

While no link was found between shift work and increased smoking or a higher cardiovascular risk, there was evidence of an association with high uric acid levels and less moderate/high physical activity.