Female Dialysis Patients Face Greater Infection, Withdrawal-Related Mortality Risk

Jessica Harding, PhD

Credit: National Institutes of Health

New research is shedding light on disparities in mortality among patients receiving maintenance dialysis for end-stage kidney disease (ESKD), with study results highlighting notable sex differences in cause-specific mortality further influenced by age and race.¹

The analysis of United States Renal Data System (USRDS) data between 2000 and 2020 found female patients on dialysis have a 3% greater likelihood of mortality and are at a greater risk of infection and withdrawal-related mortality, while male patients are more likely to die from cardiovascular disease (CVD) or cancer. Further analysis revealed these risks are especially pronounced among younger women and older men.¹

According to the American Kidney Fund, an estimated 35.5 million people in the US have kidney disease, about 808,000 of whom are living with kidney failure. Although kidney transplantation is widely considered to be the best treatment for ESKD, less than 3% of people with newly diagnosed kidney failure in 2023 were able to receive a transplant before starting dialysis. Currently, more than 557,000 people in the US are on dialysis.²

“Despite a growing body of evidence of sex differences in cause-specific mortality, contemporary US data on cause-specific mortality by sex, beyond 1 year, and by age and race, is lacking,” Jessica Harding, PhD, an epidemiologist and associate professor at Emory University School of Medicine, and colleagues wrote.1 “Such information is needed to help guide strategies to mitigate mortality risk in this high-risk population where a one-size-fits-all approach may not be suitable.”

To address this gap in research, investigators examined USRDS data for 2,161,269 US adults ≥ 18 years of age who initiated dialysis for ESKD between 2000 and 2020. Death data, including cause of death, was obtained through the Centers for Medicare and Medicaid (CMS) death notification form, complemented by the CMS enrollment database, patient files in the ESKD Quality Reporting System data, and Organ Procurement and Transplantation Network transplant data.¹

All individuals were followed from dialysis start date until death date, transplant, 10 years, or end of follow-up in December 2021, whichever occurred first.¹

Of the 2,161,269 patients with ESKD who initiated dialysis between 2000 and 2020, 43.3% were female and the mean age was 62.9 ± 15.0 years. Among the cohort, 832,259 men (67.9%) and 658,043 women (70.4%) died receiving maintenance dialysis with median survival times of 2.69 (interquartile range [IQR],1.17-5.19) and 2.72 (IQR, 1.16- 5.21) years, respectively.¹

Investigators noted CVD was the leading cause of mortality, accounting for 38.6% of deaths in women and 40.2% of deaths in men. Withdrawal (11.1% women; 9.6% men) and infections (9.8% women; 8.6% men) also accounted for significant proportions of deaths in the analysis.¹

Upon analysis, women had a 9% (adjusted hazard ratio [aHR],1.09; 95% CI, 1.08-1.11) and 15% (aHR, 1.15; 95% CI, 1.14-1.17) greater likelihood of infection and withdrawal-related mortality compared with men, respectively. Conversely, investigators pointed out women had a 7% (aHR, 0.93; 95% CI, 0.92-0.94) and 10% (aHR, 0.90; 95% CI, 0.87-0.92) lower likelihood of CVD and cancer-related mortality, respectively, compared with men.¹

They observed significant interactions between sex and age (P <.001) for each cause-specific outcome, and between sex and race for CVD (P <.001), cancer (P <.001), and infection (P <.01)-related mortality, but not withdrawal-related mortality (P = .90).¹

By age, investigators noted younger women, specifically those 18-44 years of age, had an increased likelihood of excess mortality across all specific causes. They were 8%, 28%, and 21%, more likely to die from CVD, infection, and cancer than men the same age. However, women ≥ 75 years of age were 14%, 5%, and 25% less likely to die from these same causes than men ≥ 75 years of age, respectively.¹

By race, non-Hispanic Black women had higher mortality across all specific causes than non-Hispanic Black men. Investigators noted that for all other races, sex differences were similar to the overall population.¹

“Since 2000, women in the US undergoing maintenance dialysis are more likely to die from infection and dialysis withdrawal, while men are more likely to die from CVD and cancer,” investigators concluded.¹ “A sex-specific approach that incorporates intersectionality of both age and race in the management of complications among dialysis patients may be recommended to mitigate excess mortality risks.”

References

1. ^{Abi N, Rossi A, Pastan SO, et al. Sex and Cause-Specific Mortality among US Adults Receiving Maintenance Dialysis: A National U.S. Cohort Study 2000-2021. Kidney360. doi:10.34067/KID.0000000741}

2. ^{American Kidney Fund. Quick kidney disease facts and stats. July 19, 2024. Accessed February 17, 2025. https://www.kidneyfund.org/all-about-kidneys/quick-kidney-disease-facts-and-stats}