Polypharmacy Is Associated With Accelerated Deterioration of Renal Function in Cardiovascular Outpatients

BACKGROUND: Polypharmacy is associated with poor prognosis of patients with various diseases. However, it has not been precisely addressed how polypharmacy affects the clinical characteristics of the cardiovascular outpatients. The aim of this study is to search for the clinical characteristics related to the number of prescribed drugs in the cardiovascular outpatients. Also, we examine whether the number of the prescribed drugs affects the worsening of renal function. METHODS: This retrospective study was conducted using the data of 259 continuous cardiovascular outpatients who were examined complete blood count (CBC) and serum creatinine. RESULTS: In the univariate analysis, the number of prescribed drugs were associated with the number of cardiovascular diseases or their risk factors, age, white blood cells, platelet, body mass index, anemia, and chronic kidney disease stage 3b or higher. In the multivariable analysis, independent variables that significantly correlated with the number of prescribed drugs were the number of cardiovascular diseases or their risk factors, anemia, and chronic kidney disease stage 3b or higher. Among 259 patients, 208 patients received follow-up examination of serum creatinine. The number of prescribed drugs was the only factor that was associated with accelerated deterioration of renal function. CONCLUSIONS: Polypharmacy is associated not only with poor renal function but with accelerated deterioration of renal function. Polypharmacy may be causally related with renal dysfunction.