Polypharmacy, potentially serious clinically relevant drug‐drug interactions, and inappropriate medicines in elderly people with type 2 diabetes and their impact on quality of life

The aim of the study is to investigate the patterns of polypharmacy, clinical‐relevant drug‐drug interactions (DDIs), and potentially inappropriate medicines (PIMs), and whether polypharmacy, potential serious clinically‐relevant DDIs, or PIMs can be associated with low quality of life (QoL) index scores of older adults with type 2 diabetes (T2D). A cross‐sectional study was conducted using data of 670 elderly T2D sub‐cohort from a nationwide pharmacy‐based intensive monitoring study of inception cohort of T2D in Portugal. 72.09% were found on polypharmacy (≥5 medicines). Participants on polypharmacy were mostly females (P = .0115); more obese (P = .0131); have more comorbid conditions (P < .0001); more diabetes complications (P < .0001); and use more of glucose lowering drugs (P = .0326); insulin (P < .0001); chronic medicines (P < .0001); and have higher diabetes duration (P = .0088) than those without polypharmacy. 10.59% of the participants were found to have potential serious clinically relevant DDIs. The most frequent drug‐combinations were angiotensin‐converting enzyme (ACE) inhibitors with angiotensin‐receptor blockers (ARBs), aspirin with Selective serotonin reuptake inhibitors (SSRIs), and clopidogrel with calcium channel blockers. PIMs are found in 36.11% of the participants. The most common PIMs were benzodiazepines, long‐acting sulfonylureas, and iron overdose. The adjusted multivariate models show that Polypharmacy, PIMs, and potential serious clinically relevant DDIs were associated with lower QoL index scores (OR 1.80 95% CI 1.15‐2.82), (OR 1.57 95% CI 1.07‐2.28), and (OR 1.34 95% CI 0.73‐2.48) respectively. The study shows that polypharmacy, potential serious clinical‐relevant DDIs, and PIMs may correlate with risk of reduced health related QoL outcome of older adults with T2D.