Renal Function, Cardiovascular Diseases, Appropriateness of Drug Prescription and Outcomes in Hospitalized Older Patients

Introduction: Reduced estimated creatinine clearance (eCrCl) is prevalent in older patients and impacts on drug prescription. In this study, the burden of eCrCl reduction and its associated factors and impact on outcomes were analyzed. Moreover, the rate of inappropriate drug prescription according to eCrCl and its impact on outcomes were described. Methods: Data were obtained from "REgistro POliterapie SIMI" (REPOSI), a prospective observational register enrolling hospitalized patients aged ≥ 65 years. Patients enrolled from 2010-2016 with available data to calculate eCrCl according to the Cockcroft-Gault formula were included in this analysis. Results: A total of 5046 patients were available for analysis. Among these, we found an eCrCl of 45-59 mL/min in 1163 patients (23.0%), an eCrCl of 30-44 mL/min in 1128 (22.4%), an eCrCl of 15-29 mL/min in 702 (13.9%), and an eCrCl < 15 mL/min in 152 (3.0%), with several clinical factors associated with decreasing eCrCl. During follow-up, a progressively higher risk for all-cause death, cardiovascular (CV) death, any death/re-hospitalization, and CV death/re-hospitalization was found across the renal function classes. Among patients with hypertension, diabetes mellitus, atrial fibrillation, coronary artery disease, and heart failure, 476 (10.9%) were inappropriately prescribed medications according to eCrCl. During follow-up, inappropriate prescription was associated with increased risk of all-cause death (odds ratio [OR] 1.49, 95% confidence interval [CI] 1.13-1.97) and any death/re-hospitalization (OR 1.30, 95% CI 1.03-1.63). Conclusions: In older hospitalized patients, impaired eCrCl is prevalent and associated with several factors, polypharmacy in particular. Patients with reduced eCrCl have a higher risk of major clinical outcomes, and > 10% of them are prescribed an inappropriate drug, with a higher risk for major clinical outcomes.