Low eGFR Is a Strong Predictor of Worse Outcome in Hospitalized COVID-19 Patients

Background: The clinical course of COVID-19 is more severe in elderly patients with cardio-metabolic co-morbidities. Chronic kidney disease is considered an independent cardiovascular risk factor. We aimed to evaluate the impact of reduced eGFR on the composite outcome of admission to ICU and death in a sample of consecutive COVID-19 hospitalized patients. Methods: We retrospectively evaluated clinical records of a consecutive sample of hospitalized COVID-19 patients. A total of 231 patients were considered for statistical analysis. The whole sample was divided in two groups on the basis of eGFR value, e.g., ≥ or <60 mL/min/1.73 m(2). Patients with low eGFR were further divided among those with a history of chronic kidney disease (CKD) and those without (AKI, acute kidney injury). The primary outcome was a composite of admission to ICU or death, whichever occurred first. The single components were secondary outcomes. Results: Seventy-nine (34.2%) patients reached the composite outcome. A total of 64 patients (27.7%) died during hospitalization, and 41 (17.7%) were admitted to the ICU. A significantly higher number of events was present among patients with low eGFR (p < 0.0001). Age (p < 0.001), SpO2 (p < 0.001), previous anti-platelet treatment (p = 0.006), Charlson’s Comorbidities Index (p < 0.001), serum creatinine (p < 0.001), eGFR (p = 0.003), low eGFR (p < 0.001), blood glucose levels (p < 0.001), and LDH (p = 0.003) were significantly associated with the main outcome in univariate analysis. Low eGFR (HR 1.64, 95% CI 1.02–2.63, p = 0.040) and age (HR per 5 years 1.22, 95% CI 1.10–1.36, p < 0.001) were significantly and independently associated with the main outcome in the multivariate model. Patients with AKI showed an increased hazard ratio to reach the combined outcome (p = 0.059), while those patients with both CKD had a significantly higher probability of developing the combined outcome (p < 0.001). Conclusions: Patients with reduced eGFR at admission should be considered at high risk for clinical deterioration and death, requiring the best supportive treatment in order to prevent the worst outcome.