P1515IMPACT OF POLYPHARMACY ON ALL-CAUSE MORTALITY, ALL-CAUSE HOSPITALIZATION AND CARDIOVASCULAR EVENTS IN INITIAL JAPANESE HEMODIALYSIS PATIENTS

Abstract

Abstract Background and Aims Polypharmacy (PP) is common in end-stage chronic renal disease patients, largely because of the existence of multiple comorbid conditions. PP has the potential for harm and benefits, and the association between PP and mortality and morbidity in hemodialysis patients currently remains unclear. We examined the association of PP and the risk of clinical outcomes, such as all-cause mortality, all-cause hospitalization and cardiovascular events, in initial hemodialysis patients at admission and discharge. Method Study design: Cohort study. Setting: Participants: One hundred and fifty-two initial hemodialysis patients (female vs. male, 88 vs. 64; mean age, 70.3 years) were enrolled between February 2015 and March 2018 at the Nobeoka Prefectural Hospital and Chiyoda Hospital. Predictor: Patients were divided into 2 groups according to PP (6 or more drug prescriptions, or less) during admission and discharge for the initiation of hemodialysis. Outcomes: All-cause mortality, all-cause hospitalization and cardiovascular events (hospitalization due to stroke, ischemic heart disease or peripheral artery disease) during the mean 2.8-year follow-up. Measurements: Hazard ratios (HRs) were estimated using Cox’s model for the relationships between PP and the clinical outcomes, and adjusted for potential confounders, including age, sex, body mass index, systolic and diastolic blood pressure, Charlson comorbidity risk index, hemoglobin, serum levels of albumin, albumin-corrected Ca, phosphate, parathyroid hormone, C-reactive protein and NT-proBNP; and use of erythropoietin stimulating agents. The group with 5 or less drug prescriptions was set as reference. Results Among the patients in this cohort study, the number of prescribed drugs per patient averaged 7.4 at admission and 6.9 at discharge for initial hemodialysis. One hundred (65.8%) and 94 patients (61.8%) had PP at admission and discharge, respectively. During follow-up, 20 patients died, 71 patients were hospitalized and 25 patients had cardiovascular events. PP at admission is significantly associated with cardiovascular events (HR 8.50, 95%CI 1.45-49.68). Furthermore, PP at discharge is significantly associated with all-cause hospitalization and cardiovascular events (HR 1.95, 95%CI 1.01-3.70; HR 53.16, 95%CI 2.70-104.62, respectively). However, PP is not significantly associated with all-cause mortality at admission or discharge. Conclusion Among Japanese patients starting hemodialysis, PP may be associated with clinical outcomes. However, it remains unclear whether PP is the direct cause of the outcomes or is simply a marker for increased risk of outcomes.