Increasing medication usage and polypharmacy in type 2 diabetes: The Danish experience from 2000 to 2020

Objective

Type 2 diabetes often coexists with other conditions that are mendable to pharmacological treatment. We hypothesised that polypharmacy in 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 analysed the medication usage 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, totalling 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 for polypharmacy was substantial, with 89% (409,062/461,849) being exposed to ≥5 medications at some point and 47% (n=217,467/461,849) to ≥10 medications. The increases were driven by an expanding group of medications, where analgesics, antihypertensives, proton pump inhibitors, and statins had 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 usage and polypharmacy have increased in type 2 diabetes. While the implications and appropriateness of this increased medication use are uncertain, the results stress the increasing need for healthcare personnel to understand the potential risks associated with polypharmacy, including medication interactions, adverse effects and over- and underprescribing.