Abstract

Background: The relationship between the use of multiple medications and the risk of chronic kidney disease (CKD) warrants investigation. The aim of this study was to examine the association between polypharmacy and CKD.

Methods: A population-based case-control study was conducted using data from the Taiwanese National Health Insurance Research Database.Medication usewas assessed from2002 to 2003, and newly diagnosed CKD using the International Classification of Disease, 9th revision, ClinicalModification (ICD-9
CM) from 2004 to 2011 was analyzed. Propensity score analysis was used to recruit 3,249 cases and 3,249 controls through random selection. The risk of CKD was compared among individuals who used less than five medicines per day and those who used more than five medicines per day.

Results: A dose-response relationship was observed between the number of medications used and the risk of CKD. Propensity score analysis showed an increased risk of CKD among patients who used five to nine medicines per day (odds ratio (OR), 1.90; 95% CI, 1.69–2.14) and those who used more than ten
medicines per day (OR, 3.06; 95% Cl, 3.61–2.60). Nevertheless, the use of ICD codes to identify CKD may result in misclassification bias. The severity of renal impairment was not assessed. Non-adherence and over-the-counter drugs were not accounted for.

Conclusion: In a nationwide study, polypharmacy was found to be associated with CKD in the older population, and this trend persisted after propensity score matching. There was a positive correlation between the number of medications used and the incidence of CKD.