Compared with male patients, female patients have been found to have a higher risk of all-cause mortality in the first five years post-dialysis initiation—a difference driven by higher mortality from infections and dialysis withdrawals.
These findings have been published in the American Journal of Kidney Diseases (AJKD) by Wai Lim (Sir Charles Gairdner Hospital, Perth, Australia) and colleagues.
The authors note that higher early mortality rates on dialysis have, at times, been observed among female patients compared to their male counterparts. However, discrepancies in cause-specific mortality between male and female incident dialysis patients are “not well understood” and, as such, Lim et al set out to elucidate this further via a retrospective cohort study.
Their cohort included incident patients who had initiated dialysis in Australia and New Zealand from 1998–2018. The key outcomes of their analysis were cause-specific and all-cause mortality on dialysis. The researchers also note that they censored for kidney transplantation, and applied adjusted, cause-specific, proportional hazards models, focusing on the first five years following initiation of dialysis.
Among 53,414 patients (39% female), followed for a median period of 2.8 years, 27,137 (51%) died, with the predominant cause of death being attributed to cardiovascular disease (CVD, 18%) followed by dialysis withdrawal (16%).
Compared to male patients, female patients were more likely to die in the first five years after dialysis initiation (adjusted hazard ratio [aHR] of 1.06). And, Lim et al report, while female patients experienced a lower risk of CVD-related mortality (aHR 0.93) compared to male patients, they experienced a greater risk of infection-related (aHR 1.20) and dialysis withdrawal-related (aHR 1.19) mortality.
After acknowledging the possibility of residual and unmeasured confounders as a potential limitation, the authors conclude that their research could help to inform the study of sex differences in mortality in other geographic settings.