Patterns of Potentially Inappropriate Medication Use Across Three Cohorts of Older Medicaid Recipients

Abstract

BACKGROUND Potentially inappropriate medication use is a serious quality concern, especially when it occurs in more vulnerable older adults or for extended durations. OBJECTIVE To characterize patterns of inappropriate medication use and duration among 3 cohorts with differing health status. METHODS We identified unconditionally inappropriate drug use, using Beers 1997 criteria, among 3185 older Kansas Medicaid beneficiaries. Claims from May 2000 to April 2001 provided data for 3 cohorts: nursing facility (NF) residents, recipients of home- and community-based services through the Frail Elderly (FE) program, and persons with neither NF/FE care (Ambulatory). Duration, categorized as short-term (≤1 month's supply), extended (>1–9 mo), or chronic (>9–12 mo), was determined for each drug and cohort. Drug–disease associations were explored. RESULTS Any inappropriate medication use occurred in 21%, 48%, and 38% of Ambulatory, FE, and NF cohorts, respectively. Inappropriate analgesics, antihistamines, antidepressants, muscle relaxants, and oxybutynin were most common, but prevalence and duration varied by cohort. Short-term analgesic and antihistamine use was common. FE cohort members had the highest use rates for all drugs. The NF cohort had less antidepressant and muscle relaxant use. Drug–disease associations were noted for amitriptyline use in diabetes mellitus, propoxyphene use in musculoskeletal and upper gastrointestinal conditions, and muscle relaxant use in musculoskeletal conditions. CONCLUSIONS Cross-sectional, one-year prevalence figures are comprised of both short- and long-term use that varies by drug and cohort. NF residence is associated with reduced use of drugs scrutinized during mandated medication review. Relevant diseases are associated with specific inappropriate prescribing. Future efforts should target extended and chronic duration of use and persons at highest risk for adverse effects, including recipients of home- and community-based care.