The association of sex differences in ambulatory blood pressure with cardiovascular events and mortality in dialysis patients

Abstract

Male patients with pre-dialysis chronic kidney disease (CKD) have worse ambulatory blood pressure (BP) control than females; this is associated with higher mortality. Male hemodialysis patients have higher ambulatory BP levels than females. This analysis aimed to investigate the association of sex differences in ambulatory BP with cardiovascular events and mortality in hemodialysis individuals. 129 male and 91 female hemodialysis patients with valid 48-h BP monitoring were followed for 53.4 ± 31.1 months. The primary endpoint was cardiovascular mortality; the secondary endpoint was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, resuscitation after cardiac arrest, heart failure-hospitalization, coronary or peripheral revascularization. Cumulative freedom from the primary endpoint was lower for women (logrank-p = 0.032), while cumulative-freedom from the secondary endpoint did not differ significantly between-groups (logrank-p = 0.644). The crude risk for cardiovascular mortality was significantly higher in women (HR = 1.613, 95% CI [1.037, 2.509]). The crude risk for the combined endpoint was not different between the two groups (HR = 0.918, 95% CI [0.638, 1.320]). After adjusting for major risk factors (age, diabetes, dialysis vintage, coronary disease and hemoglobin) no significant differences in the risk for both the primary and the secondary endpoint were observed between women and men (primary: HR = 1.295 (95% CI [0.808, 2.078]), secondary: HR = 0.763 (95% CI [0.521, 1.118])). After additional adjustment for 44-h systolic BP the above relationships did not alter (primary: HR = 1.329 (95% CI [0.826, 2.137]), secondary: HR = 0.808 (95% CI [0.551, 1.184])). In conclusion, female hemodialysis patients have higher crude but similar adjusted cardiovascular mortality rates compared to male counterparts. In contrast to pre-dialysis CKD, the neutral relationship between gender and adverse cardiovascular outcomes in hemodialysis is not further affected by ambulatory BP.