Increased risk of fatal infections in women starting peritoneal dialysis

Although cardiovascular disease (CVD) is an important cause of morbidity and mortality in patients with end-stage renal disease, non-CVD causes account for more than 50% of total deaths. We previously showed that, compared with men, women starting dialysis-- both hemodialysis and peritoneal dialysis (PD)--have higher non-CVD mortality rates. Here, we evaluate sex-specific outcomes in a large cohort of incident PD patients.

Incident de novo PD patients from the Andalusian SICATA Registry for 1999 - 2010, with follow-up until 31 December 2010 or up to 5 years, were investigated for fatal outcomes. Causes of death were extracted from medical records. The analysis used traditional and competing-risk Cox models for all-cause and cause-specific mortality in men and women, correcting in the competing-risk models for the events of kidney transplantation and transfer to hemodialysis.

A total of 1458 patients (57% men; mean overall age: 55.3 ± 17.0 years) initiated PD in Andalusia during the study period. During follow-up, 350 deaths, 355 renal transplantation procedures, and 331 transfers to hemodialysis were recorded. Vascular disease and diabetic nephropathy were the most frequent causes of kidney failure in men; other causes were more common in women. In the traditional Cox model, both sexes showed a similar all-cause mortality risk [crude hazard ratio (HR): 0.90; 95% confidence interval (CI): 0.72 to 1.12]. However, with respect to specific causes of death, women showed a borderline lower risk of both CVD (crude HR: 0.71; 95% CI: 0.50 to 0.99) and non-CVD mortality from other than infection (crude HR: 0.81; 95% CI: 0.57 to 1.15). In contrast, the risk of death from infection was almost doubled in women compared with men (crude HR: 1.92; 95% CI: 1.15 to 3.20), a finding that held true after multivariate adjustment for age, primary renal disease, period of inclusion, and initial PD modality (adjusted HR: 1.76; 95% CI: 1.03 to 3.01). This result was confirmed even taking into consideration the competing events of kidney transplantation and transfer to hemodialysis.

Compared with men starting PD, women starting PD are at higher risk of mortality from infection. More stringent screening measures and corrective efforts in women might be indicated.