Increasing Medication Use and Polypharmacy in Type 2 Diabetes: The Danish Experience From 2000 to 2020

Abstract

OBJECTIVE Type 2 diabetes often coexists with other conditions that are amenable to pharmacological treatment. We hypothesized that polypharmacy among individuals with type 2 diabetes has increased since 2000. RESEARCH DESIGN AND METHODS Using Danish national registries, we established a cohort of all Danish individuals (aged ≥18 years) with type 2 diabetes between 2000 and 2020. We analyzed their medication use and prevalence of varying degrees of polypharmacy (≥5 or ≥10 medications), stratifying by age, sex, number of chronic diseases, and socioeconomic status. RESULTS The cohort grew from 84,917 patients in 2000 to 307,011 in 2020, totaling 461,849 unique patients. The number of daily medications used per patient increased from (mean ± SD) 3.7 ± 2.8 (in 2000) to 5.3 ± 3.2 (in 2020). The lifetime risk of polypharmacy was substantial, with 89% (n = 409,062 of 461,849) being exposed to ≥5 medications at some point and 47% (n = 217,467of 461,849) to ≥10 medications. The increases were driven by an expanding group of medications, with analgesics, antihypertensives, proton pump inhibitors, and statins having the largest net increase. Advanced age, male sex, lower socioeconomic status, and Danish ethnicity positively correlated with polypharmacy but could not explain the overall increase in polypharmacy. CONCLUSIONS Medication use and polypharmacy have increased among patients with type 2 diabetes. Although the implications and appropriateness of this increased medication use are uncertain, the results stress the increasing need for health care personnel to understand the potential risks associated with polypharmacy, including medication interactions, adverse effects, and over- and underprescribing.