Researchers at the University of Calgary’s Cumming School of Medicine have found that the usual female survival advantage does not extend to patients with end‑stage kidney disease. In a population‑based cohort of 7,506 adults with incident stage 5 chronic kidney disease (CKD) in Alberta, Canada, women under age 55 experienced higher mortality and were less likely to receive a kidney transplant than men of the same age.
Study design and key findings
The retrospective study linked provincial health‑administrative databases, laboratory records and vital‑statistics data to follow patients from the time they first met criteria for stage 5 CKD (estimated glomerular filtration rate < 15 mL/min/1.73 m² for at least three months). Participants were grouped into six five‑year age brackets, and outcomes were compared with age‑ and sex‑matched rates in the general Alberta population.
Overall, 54.9 % of the cohort were male (4,121) and 45.1 % female (3,385). Over a median follow‑up of 7.9 years, women under 45 had a standardized mortality ratio (SMR) of 47.5, more than three times the SMR of 12.0 observed in men of the same age. Even in the 55‑64‑year group, women’s SMR (14.1) exceeded men’s (8.5). By contrast, in patients 85 years and older the SMRs for both sexes converged at around 4.2.
Five‑year crude mortality risk after a stage 5 CKD diagnosis was 58.9 % for women compared with 51.9 % for men. Death without receiving kidney replacement therapy (KRT) occurred in 39.9 % of women versus 28.3 % of men. Transplantation was performed in 8.5 % of female patients, less than half the 14.5 % rate observed in males.
Why the findings matter
Globally, CKD affects about 10 % of adults, and stage 5 disease is the final common pathway before dialysis or transplantation. According to the World Health Organization, CKD is responsible for an estimated 1.2 million deaths each year. The new evidence suggests that women with advanced kidney disease face a disproportionate risk of death and reduced access to life‑saving transplantation, challenging the long‑standing observation that women outlive men by roughly six years in the general population—a pattern highlighted in a recent NPR report on longevity.
Expert commentary
“Historically, most CKD studies have focused on earlier stages and on patients seen in nephrology clinics, which underrepresents those with the most severe disease,” said Dr. Christian Chan, postdoctoral associate at the Cumming School of Medicine. “Our province‑wide data show that once kidney function declines to the point of needing replacement therapy, the protective effect of female sex disappears, and in younger patients it is reversed.”
Dr. Nephrologist Dr. Anita Patel of the Canadian Kidney Foundation, who was not involved in the study, noted that socioeconomic factors, referral biases and differences in comorbid conditions may contribute. “Women often have higher rates of frailty and may be evaluated less aggressively for transplant eligibility,” she explained. “Addressing these disparities will require systematic screening and equitable referral pathways.”
Public‑health and policy implications
The findings underscore the need for gender‑aware strategies in CKD management. Provincial health authorities could consider mandating routine transplant eligibility assessments for all stage 5 patients, regardless of sex, and expanding education for primary‑care providers on referral criteria. Moreover, the Canadian Institute for Health Information reports that women are less likely to be placed on the deceased‑donor transplant list, hinting at structural barriers that merit investigation.
From a broader perspective, improving early detection of CKD—a condition often silent until advanced—remains a priority. The National Institutes of Health emphasizes that controlling hypertension and diabetes, the two leading causes of CKD, can delay progression to stage 5 and reduce the need for transplantation.
Next steps in research
The authors plan to explore biological mechanisms, such as hormonal influences on cardiovascular risk and immune response, that may affect outcomes after kidney failure. They also aim to analyze whether differences in dialysis modality (home versus in‑center) influence survival disparities. International collaboration with KDIGO could help determine whether similar sex‑based patterns exist in other health systems.
Patients with CKD and their families are encouraged to discuss transplant eligibility early with their nephrologist and to advocate for comprehensive evaluation. Clinicians should remain vigilant for potential bias in referral decisions and ensure that treatment options are presented equitably.
Read more on Globally Pulse Health.
