Prevalence and trends of polypharmacy in U.S. adults, 1999–2018

Abstract

Background: Polypharmacy is one of the most important health issues for its potential impacts on disease burden and healthcare costs. The aim of this study was to update a comprehensive picture of prevalence and trends in polypharmacy over 20 years in U.S. adults. Methods: Participants included 55,081 adults aged ≥ 20 from the National Health and Nutrition Examination Survey, January 1, 1999, through December 31, 2018. The simultaneously use of ≥ 5 drugs in one individual was defined as polypharmacy. National prevalence and trends in polypharmacy were evaluated among U.S. adults within different demo-socioeconomic status and pre-existing diseases. Results: From 1999–2000 to 2017–2018, the overall percentages of adults with polypharmacy remained on the rise, increasing from 8.2% (7.2–9.2%) to 17.1% (15.7–18.5%) (average annual percentage change [AAPC] = 2.9%, P =.001). The polypharmacy prevalence was considerably higher in the elderly (from 23.5% to 44.1%), in adults with heart disease (from 40.6% to 61.7%), and in adults with diabetes (from 36.3% to 57.7%). Also, we observed a greater increase rate of polypharmacy in men (AAPC = 4.1%, P