Mortality risk for women on chronic hemodialysis differs by age.

BACKGROUND

Previous reports have demonstrated similar survival for men and women on hemodialysis, despite women's increased survival in the general population.

OBJECTIVES

To examine the effect of age on mortality in women undergoing chronic hemodialysis.

DESIGN

A retrospective cohort study using an administrative data registry, the Canadian Organ Replacement Registry (CORR) from Jan. 2001 and Dec. 2009.

SETTING

Canada.

PATIENTS

28,971 (Women 11,792 (40.7%), Men 17,179 (59.3%)) incident chronic hemodialysis patients who survived greater than 90 days on dialysis.

MEASUREMENTS

All-cause mortality.

METHODS

Cox proportional hazards and competing risks models were employed to determine the independent association between sex, age and likelihood of all-cause mortality with renal transplantation as the competing outcome.

RESULTS

During the study period, 6060 (51.4%) of women and 8650 (50.4%) of men initiating dialysis died. Younger women experienced higher mortality (Age < 45: Women 22.5%, Men 18.2%, hazard ratio (HR) 1.31 (1.12-1.52)) whereas elderly women experience lower mortality (Age 75-85: Women 65%, Men 67.3%, HR 0.94 95% CI 0.88-0.99, Age > 85: Women 66%, Men 70.2%, HR 0.83 95% CI 0.71-0.97) compared to men. This relationship persisted after accounting for the competing risk of transplantation.

LIMITATIONS

The cause of death was unknown.

CONCLUSIONS

Women's survival on chronic hemodialysis varies by age compared to men with a significantly higher mortality in women younger than 45 years old and lower mortality in woman older than 75 years of age.