National study of medications associated with injury in elderly Medicare/Medicaid dual enrollees during 2003

Abstract

ObjectivesTo address the association between inappropriate prescribing for the elderly and adverse outcomes and to identify the magnitude of the cost of medication-associated injury in this population. DesignCross sectional. SettingUnited States, 2003. Patients5,412,678 dually eligible Medicare/Medicaid enrollees aged 65 years or older. InterventionBeers and non-Beers medications with potential central nervous system adverse effects of dizziness/vertigo, drowsiness, and/or fainting were assessed. Emergency department (ED) visits with admitting diagnoses pertaining to injuries for elderly enrollees dually eligible for Medicare and Medicaid during the calendar year were linked to prescriptions filled during the 90 days preceding the visit. Main outcome measureFor each drug, the proportion of ED-related fills and the Medicare average revenue charge per injury-related ED visit were calculated. ResultsSeveral drugs not currently on the Beers list were found to be associated with high proportions of ED-related fills: methadone had the highest proportion of any of the drugs studied (12.3 per 1,000 fills), and bethanechol (7.8 per 1,000 fills) had the highest proportion among genitourinary products. Regarding narcotic analgesics, propoxyphene (7.7 per 1,000 fills) had a higher association with injury than morphine (6.6 per 1,000 fills) or tramadol (6.5 per 1,000 fills). For cardiovascular agents, clonidine (4.7 per 1,000 fills) and doxazosin (3.6 per 1,000 fills) had higher associations with injury than nifedipine (3.3 per 1,000 fills). Fentanyl, a non-Beers medication, was associated with the most expensive injury-related ED visits ($1,263 average revenue charge). ConclusionBeers medications are associated with high injury-related ED visit rates for the elderly, and a number of drugs not currently on the Beers list also pose an apparent risk for injury-related visits.