Sex-Specific CKD Trends and High Ambient Temperature–Attributable Mortality in the United States, 1990–2023: A GBD 2023 Analysis

Background Chronic kidney disease (CKD) remains a major public health burden in the United States, affecting over 35 million adults. Despite improvements in the management of hypertension and diabetes, sex-based disparities in CKD burden persist, with women exhibiting higher prevalence but men facing worse outcomes. High ambient temperature has been associated with dehydration, renal hypoperfusion, and kidney injury, although the contribution of heat to CKD mortality is commonly estimated through modeled comparative risk assessment rather than direct individual-level exposure measurements. Objective This study quantified changes in absolute and relative sex disparities in CKD incidence, prevalence, and mortality in the United States from 1990 to 2023 and secondarily examined sex-specific and geographic patterns in modeled high ambient temperature–attributable CKD mortality. Methods A retrospective analysis was conducted using age-standardized CKD incidence, prevalence, and mortality rates per 100,000 population, stratified by sex. Sex differences were summarized using rate differences (Female − Male) and rate ratios (Female/Male). Temporal and sex-gap trends were assessed using ordinary least squares regression (OLS) as a descriptive analysis, reporting β coefficients with 95% confidence intervals (CIs); GBD estimates are presented with 95% uncertainty intervals (UIs). Newey-West HAC standard errors and approximate inverse variance weighted regression were used as sensitivity analyses. Results From 1990–2023, females had higher CKD incidence and prevalence, whereas males had higher CKD mortality. Female incidence declined (β = −0.205 per year [95% CI: −0.338, −0.072]) while male incidence was compatible with little linear change (β = 0.084 [95% CI: −0.041, 0.209]); the incidence sex gap narrowed (β = −0.289 [95% CI: −0.317, −0.261]). Prevalence increased in both sexes, with a stable sex gap (β = 0.53 [95% CI: −1.89, 2.95]). Mortality increased in both sexes, and the male excess widened (β = −0.170 [95% CI: −0.192, −0.147]). Modeled high ambient temperature–attributable CKD mortality increased from 0.020 to 0.178 deaths per 100,000 among males and from 0.013 to 0.129 among females between 1990 and 2023. The attributable fraction of total CKD mortality increased from approximately 0.19% to 0.63–0.64%. Results were consistent across OLS, HAC-adjusted, and inverse-variance-weighted analyses. Conclusions From 1990 to 2023, CKD burden in the United States showed persistent sex differences: females had higher incidence and prevalence, whereas males experienced higher mortality with a widening mortality gap over time. Modeled heat-attributed CKD mortality increased over time, and regional heterogeneity supports further study of climate-related kidney risks and climate-resilient prevention strategies.