The Association Between the Number of Prescription Medications and Incident Falls in a Multi-ethnic Population of Adult Type-2 Diabetes Patients: The Diabetes and Aging Study

BACKGROUND: Use of four or more prescription medications is considered a risk factor for falls in older people. It is unclear whether this polypharmacy-fall relationship differs for adults with diabetes. OBJECTIVE: We evaluated the association between number of prescription medications and incident falls in a multi-ethnic population of type-2 diabetes patients in order to establish an evidence-based medication threshold for fall risk in diabetes. DESIGN: Baseline survey (1994-1997) with 5 years of longitudinal follow-up. PARTICIPANTS: Eligible subjects (N=46,946) had type-2 diabetes, were >= 18 years old, and enrolled in the Kaiser Permanente Northern California Diabetes Registry. MEASUREMENTS AND MAIN RESULTS: We identified clinically recognized incident falls based on diagnostic codes (ICD-9 codes: E880-E888). Relative to regimens of 0-1 medications, regimens including 4 or more prescription medications were significantly associated with an increased risk of falls [4-5 medications adjusted HR 1.22 (1.04, 1.43), 6-7 medications 1.33 (1.12, 1.58), >7 medications 1.59 (1.34, 1.89)]. None of the individual glucose-lowering medications was found to be significantly associated with a higher risk of falls in predictive models. CONCLUSIONS: The prescription of four or more medications was associated with an increased risk of falls among adult diabetes patients, while no specific glucose-lowering agent was linked to increased risk. Baseline risk of falls and number of baseline medications are additional factors to consider when deciding whether to intensify diabetes treatments.