Heparanase procoagulant activity, factor Xa, and plasminogen activator inhibitor 1 are increased in shift work female nurses

Epidemiologic studies indicate on an increased risk of cardiovascular disease and cancer in shift workers, although the underling mechanism is obscure. Heparanase directly enhances tissue factor (TF) activity leading to increased factor Xa production and subsequent activation of the coagulation system. In the present study, a comparison of coagulation markers among healthy shift working (SW) vs. healthy daytime working (DW) female nurses was performed. Thirty SW and 30 DW female nurses were enrolled. For each of the 60 participants, blood was drawn between 7:00 and 8:00 a.m. and at least 8 h after the last work shift. Plasma was studied for coagulation marker that included TF/heparanase procoagulant activity, TF activity, heparanase procoagulant activity, heparanase level, factor Xa level, plasminogen activator inhibitor 1 (PAI-1), plasminogen, α₂-antiplasmin, fibrinogen, global protein C, von Willebrand factor, and D-dimer by chromogenic assays and enzyme-linked immunosorbent assays (ELISAs). Sleep quality was assessed by self-report according to the Pittsburgh Sleep Quality Index. The heparanase procoagulant activity increased by 2-fold and the TF/heparanase procoagulant activity increased by 1.5-fold in SW nurses compared to DW nurses (P < 0.05). Factor Xa levels and PAI-1 levels were significantly higher among SW nurses compared to the DW group (22 vs. 18 ng/ml, P < 0.05, and 32 vs. 22 ng/ml, P < 0.005, respectively). No significant differences were found in the other tested coagulation markers between the study groups. Heparanase procoagulant activity, factor Xa level, and PAI-1 level were significantly higher in SW nurses compared to the DW group. These alterations of blood coagulation activation may potentially contribute to cardiovascular and cancer morbidity.