Polycythemia and COVID-19 mortality in patients at high altitude

Ramos-Estrada M.A.; Felandro- Taco G.F.; Santos- Rosales Y.R. · Revista Cubana de Medicina Militar (2026)

Resumen

Introduction: COVID-19 mortality shows considerable variability and may be influenced by comorbidities and geographic factors. In populations living at high altitude, secondary polycythemia represents an adaptation to chronic hypoxia; however, its relationship with COVID-19 mortality remains unclear. Objective: To evaluate the association between polycythemia and in-hospital mortality in hospitalized patients with COVID-19. Methods: A retrospective analytical cohort study was conducted including 215 adults hospitalized with COVID-19 during 2021. Polycythemia was defined using altitude-adjusted hemoglobin levels. Descriptive analyses, cumulative incidence of mortality, calculation of relative risks (RR) in bivariate analysis, and binary logistic regression to obtain adjusted odds ratios (aOR) were performed. Results: The median age was 57.4 years (IQR: 21); 58.6% were male. The prevalence of polycythemia was 3.3%. In-hospital mortality reached 27%. No evidence of an association between polycythemia and mortality was found. In bivariate analysis, age ≥ 60 years, type 2 diabetes, elevated D-dimer, C-reactive protein ≥ 7.5 mg/dL, elevated ferritin, and lymphopenia were associated with increased risk of death. In multivariable analysis, advanced age, diabetes, elevated D-dimer, and elevated C-reactive protein remained independent predictors. Conclusions: Polycythemia at high altitude is not associated with COVID-19 mortality; however, age, diabetes, and inflammatory and thrombotic biomarkers do increase the likelihood of death.

Instituciones: Universidad Nacional Mayor de San Marcos; Universidad Privada Norbert Wiener