Drug use and prescribing problems in the community-dwelling elderly: a study of three state Medicaid programs

This paper describes a study of drug use and drug-related problems in community-dwelling elderly (> or =65 years) Medicaid recipients in Maryland, Iowa, and Washington from 1989 through 1996. A claim-by-claim review of Medicaid prescriptions was conducted to detect 5 types of prescribing problems (dose, duration of therapy, duplicative therapy, drug-drug interactions, and contraindications or initial therapy). The study examined 8 drug categories: angiotensin-converting enzyme (ACE) inhibitors, antidepressant agents, antipsychotic agents, benzodiazepines, calcium channel blockers, digoxin, histamine2-receptor antagonists, and nonsteroidal anti-inflammatory drugs. The total number of persons with prescriptions in any of the 8 drug classes increased over the 8-year period, with the greatest growth in ACE inhibitors. Mean annual drug use per person declined in Maryland but increased in Washington and Iowa. Despite increasing use, the overall incidence of prescribing problems fell dramatically in all 3 states, particularly for dose- and duration-related criteria. Except in the area of drug-drug interactions, this elderly population was less likely to have received a prescription falling outside commonly accepted drug utilization review criteria for 8 major drug classes in 1996 than in 1989.