Temporal Evolution of the Impact of CKD on COVID-19 Outcomes : A 5-Year Nationwide Analysis.

KEY POINTS: CKD was associated with higher odds of coronavirus disease 2019 death and hospitalization across all phases in Mexico. Patients with CKD had lower intensive care unit/invasive mechanical ventilation use but higher in-intensive care unit fatality, especially at 18-64 years, which may reflect selection effects and triage decisions. Associations attenuated in 2022 but resurged by 2024; findings remained after municipal socioeconomic status adjustment.

BACKGROUND

CKD is among the strongest predictors of adverse coronavirus disease 2019 outcomes, yet how CKD-associated risk evolved across prevaccination, roll-out, mass-vaccination, and postpandemic phases remains incompletely defined in Latin America.

METHODS

We performed a nationwide retrospective analysis of Mexico's historical surveillance open datasets, including all laboratory-confirmed cases from January 1, 2020, to June 30, 2025. The primary outcome was death among recorded cases (case fatality); secondary outcomes were hospitalization, intensive care unit (ICU) admission, and invasive mechanical ventilation (IMV). Multivariable logistic models were fit overall, by age strata and year/pandemic phase, adjusting for demographics, comorbidities, and symptom-to-care interval; temporal patterns were summarized with locally estimated scatterplot smoothing and segmented interrupted time series analysis. Sensitivity analyses included models restricted to ICU admissions and models additionally adjusted for municipal socioeconomic context.

RESULTS

Among 7,359,354 cases, 70,144 (1.0%) had CKD; crude case fatality was 33% in CKD versus 4% without. In adjusted models, CKD was associated with higher case fatality (adjusted odds ratio [aOR], 1.20; 95% confidence interval [CI], 1.19 to 1.20) and hospitalization (aOR, 1.35; 95% CI, 1.35 to 1.35), but not with ICU admission (aOR, 0.98) or IMV (0.99). In the ICU-restricted cohort, CKD independently increased in-ICU case fatality (aOR, 1.38; 95% CI, 1.25 to 1.51), the strongest at age 18-64 years (aOR, 1.52) and smaller at ≥65 years (aOR, 1.19). Year-specific models showed attenuation during mass vaccination (2022 aOR, 1.13), followed by a resurgence in 2024 (aOR, 1.90). Locally estimated scatterplot smoothing/interrupted time series revealed delayed and incomplete postvaccination benefit for CKD with trend acceleration in 2023. The findings were robust after adding municipal socioeconomic status indicators to adult models.

CONCLUSIONS

Across 5 years of nationwide surveillance, CKD remained a dominant, independent correlate of coronavirus disease 2019 case fatality and hospitalization, with risk resurging in 2024. Lower ICU/IMV use yet higher in-ICU case fatality among patients with CKD may reflect selection effects and underscore the need for rapid escalation pathways.