This nationwide cross-sectional study explored the relationship between ambulatory care fragmentation and medication use in older US adults, examining variations by chronic conditions and race. Utilizing data from the 2003-2016 REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort study linked with fee-for-service Medicare claims, the authors analyzed care fragmentation (measured by the reversed Bice-Boxerman Index) and medication counts through a 2-week in-person prescription inventory. They employed negative binomial regression, adjusting for potential confounders, and conducted subgroup analyses based on chronic conditions and race. Of the 4524 participants, 40.7% experienced high care fragmentation and 59.8% used 5 or more medications. High fragmentation was associated with a 4% overall increase in medication count ( P = 0.03), a 7% increase for those with 4+ chronic conditions ( P = 0.01), and a 9% increase for Black participants ( P = 0.01). In conclusion, fragmented care is independently associated with greater polypharmacy, particularly among Black older adults and those with multiple chronic conditions.
Keywords: ambulatory care; fragmentation; medicare; medication; polypharmacy.
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