Drug-Associated Hospital Admissions in Older Medical Patients
From the Geriatric Clinical Pharmacology Unit, Departments of Medicine and Pharmacology and Therapeutics, Faculties of Medicine and Pharmacy, University of Manitoba, Canada.
This study was supported by a grant from the Manitoba Medical Services Foundation.
Presented at the meeting of the Royal College of Physicians and Surgeons of Canada, Toronto, September 1986.
Abstract
A survey of drug-related admissions of patients aged 50 years and older was conducted at the Health Sciences Centre, Winnipeg to determine the interrelationship of risk factors, and isolate the effect of age. All nonelective medical admissions were prospectively assessed to determine the role of drug therapy as a contributory factor. Of the 863 eligible admissions, 162 exhibited at least one drug-related adverse patient event (DRAPE) at the time of hospitalization. This accounted for 19% of the admissions (23% of 718 admissions that involved prescription drugs). Although adverse drug reactions were responsible for many DRAPEs (48%), intentional noncompliance (27%), treatment failure (19%), alcohol (14%), and medication error (10%) were also frequent contributing causes. Drugs commonly implicated in DRAPEs were systemic steroids, digoxin, nonsteroidal anti-inflammatory agents, α-methyldopa, calcium channel blockers, β-blockers, theophylline, furosemide, sympathomimetics, thiazides, and benzodiazepines. The risk of a DRAPE was related to the number of diseases prior to admission (r = 0.81; P < .026) and the number of drugs used (r = 0.77; P < .001). Age was not correlated with the risk of a DRAPE. Females had significantly more adverse drug reactions, although sex was not a predictor for overall DRAPE risk.