Clinically relevant drug‐drug interactions and the risk for drug adverse effects among home‐dwelling older persons with and without type 2 diabetes

WHAT IS KNOWN AND OBJECTIVE: Polypharmacy and age are known to increase the risk for potential drug interactions. Type 2 diabetes has been associated with polypharmacy and several comorbidities. Currently, there is no information on whether the frequency of clinically relevant drug-drug interactions and the risk for drug adverse effects differ between older persons with and without diabetes. The aim of this study was to investigate the frequency of drug-drug interactions and the risk for drug adverse effects in these two groups in primary care. METHODS: The basic study population consisted of Finnish home-dwelling primary care patients aged ≥ 65 years (N = 3039). For each person with diabetes, two controls were selected with adjusted age and gender. To collect data, electronic primary care patient records, a structured health questionnaire and a structured health examination conducted by a physician were utilized. Using the SFINX-PHARAO® database, drug-drug interactions and the risk for drug adverse effects were evaluated in 182 persons with type 2 diabetes and 176 persons without diabetes. RESULTS AND DISCUSSION: There were no significant differences in the frequency of drug-drug interactions or the risk for drug adverse effects in persons with and without diabetes. At least one clinically relevant interaction was found in 81 (44.5%) persons with diabetes and 73 (41.5%) persons without diabetes. The most common drugs causing interactions included non-steroidal anti-inflammatory drugs (NSAIDs) and warfarin. WHAT IS NEW AND CONCLUSION: There is no difference in the frequency of drug-drug interactions or risk for drug adverse effects in older home-dwelling persons with and without diabetes. Due to common comorbidities and commonly used drugs among persons with diabetes, drug-drug interactions involving warfarin or NSAIDs in particular should be carefully monitored to avoid drug adverse effects.