Systematic review and meta-analysis of the association between long working hours and hypertension risk

Background Hypertension, a major public health problem worldwide, has been linked to lifestyle factors and work conditions, with conflicting evidence on the association between long work hours and risk of hypertension. Methods We conducted a systematic review and meta-analysis of observational studies to investigate the relationship between working hours and hypertension or blood pressure, assessed the risk of bias and performed subgroup analyses. The protocol was registered with the International Prospective Register of Systematic Reviews. Results The pooled OR for the association between long working hours and risk of hypertension was 1.09 (95% CI: 0.88 to 1.35) in the 15 studies that used hypertension as the outcome. In the three studies that used blood pressure as the outcome, diastolic blood pressure was higher among those with long working hours compared with those with non-long working hours (1.24 mm Hg, 95% CI: 0.19 to 2.29). In subgroup analysis, the pooled OR for the association between long working hours and risk of hypertension was 1.28 (95% CI: 1.14 to 1.44) and 1.00 (95% CI: 0.64 to 1.56) in women and men, respectively. Conclusions Although this study could not clearly confirm the relationship between long working hours and hypertension, the subgroup analysis suggests that long working hours may be associated with hypertension, particularly among women. More reliable research is needed to establish causality.