Abstract
Rationale & Objective: Previous studies have shown chronic kidney disease (CKD) mortality rates to be lower in females than males. We aimed to examine the extent to which sex differences vary over time, among countries and with age, using Global Burden of Disease (GBD) Study data.

Study Design: Observational epidemiological study

Setting & Participants: GBD Study, which used published literature, vital registration systems, kidney replacement therapy registries and household surveys.

Exposures: Sex

Outcomes: CKD-associated mortality rate (per 100,000 population)

Analytical Approach: Changes in CKD mortality between 1990 and 2019 were compared between sexes, globally and for the 50 most populous countries. For 2019 only, sex differences in age-standardised and age-specific mortality were compared among countries.

Results: There was no change in global age-standardised mortality in either sex between 1990 and 2019, with female mortality consistently 30% lower than male mortality. Percentage changes were less favourable in females than males in two-thirds of the 50 countries examined, with the greatest change disparities observed in Egypt, Thailand and Malaysia. In Mexico, which had the greatest overall percentage increase, the increase was smaller in females (81% vs 138%). Female mortality varied between 47% lower and 60% higher than males (in Angola and Egypt, respectively) in 2019. In most countries, female mortality was lower across all age groups, with no narrowing of sex differences with age.

Limitations: We were not able to assess sex differences according to CKD stage, nor did we explore other disease metrics (e.g. disability-adjusted life years).

Conclusions: Percentage changes in age-standardised CKD mortality have tended to be less favourable in females compared to males, but with some notable exceptions. Similarly, whilst female mortality is generally lower than in males, numerous examples exist where the opposite is true. Country-specific assessments of sex differences in CKD-associated outcomes are essential for equitable care.