Trends and expenditures in polypharmacy and hyperpolypharmacy among older adults in the United States, 2002–2017

Background: Polypharmacy and hyperpolypharmacy are increasingly common among older adults and are associated with substantial clinical and economic burdens. Understanding trends in their prevalence and associated expenditures is essential to inform policy and targeted interventions. This study examines trends in the prevalence of polypharmacy and hyperpolypharmacy and their associated healthcare and medication expenditures among U.S. older adults from 2002 to 2017. Methods: This retrospective cross-sectional study used data from the Medical Expenditure Panel Survey, a nationally representative survey of the noninstitutionalized U.S. population. The study included older adults aged 65 years or older. Medication burden was categorized as polypharmacy (5–9 medications) and hyperpolypharmacy (≥ 10 medications), determined annually based on prescription records. The primary outcomes were annual prevalence estimates of polypharmacy and hyperpolypharmacy. Secondary outcomes were total healthcare and prescribed medication expenditures. Results: Our study included 61,402 adults aged 65 years or older representing a weighted population of 643 million person-years. Over 2002 − 2017, the prevalence of polypharmacy ranged from 35.1%−39.4%, while the prevalence of hyperpolypharmacy ranged from 12.5%−17.7%. Polypharmacy prevalence increased significantly until 2011 (+ 0.38%/year [0.23 ~ 0.53]; p<.001) and declined thereafter (-0.45%/year [-0.67~-0.23]; p<.001). Hyperpolypharmacy significantly increased until 2006 (+ 0.87%/year [0.14 ~ 1.59]; p=.023), with a non-significant stable period afterward. Subgroup analyses revealed a higher prevalence among individuals aged 75–84 years and among females. Asians exhibited a significant increase in polypharmacy (+ 0.83%/year [0.32 ~ 1.33]; p=.023). Total healthcare expenditures increased among individuals with polypharmacy after 2013 (+$1030/year [231 ~ 1829]; p=.016). Prescribed medication expenditures increased significantly among individuals with hyperpolypharmacy particularly after 2014 (+$939/year [319 ~ 1560]; p=.006). Conclusion: Polypharmacy and hyperpolypharmacy remain highly prevalent among older adults in the U.S., with a significant growth in medication expenditures over time among those with hyperpolypharmacy. These findings highlight the critical need for ongoing monitoring and tailored prescribing optimization efforts targeting subgroups with the high prescribing burden to reduce the clinical and economic burdens of polypharmacy and hyperpolypharmacy in aging populations.