Characterization of drug-related problems in elderly patients on admission to a medical ward.

The incidence, types, avoidability and risk factors associated with drug-related problems (DRPs) in geriatric patients on admission to a medical ward of the Toronto Hospital were assessed. The admission note and laboratory data of 150 consecutive admissions were reviewed for the presence of an adverse drug reaction, inappropriate dose, non-compliance, drug interaction, or lack of required medication. The avoidability (avoidable, possibly avoidable, or unavoidable) and contribution to hospitalization (major reason, contributing or non contributing) of each DRP was characterized. On admission, 41% of patients had a DRP identified, of which most were potentially avoidable (96.8%) and involved commonly prescribed drugs. The DRP was the major or contributing reason for admission in 31% of cases. Polypharmacy was a statistically significant risk factor for a DRP, particularly for male patients (p = 0.0010). In this elderly population, DRPs were not statistically correlated to age greater than 65 years, gender, renal function, native language, or duration of hospital stay. The incidence of DRPs and hospitalizations in the elderly can potentially be reduced by improving medication use. Enhanced communication, particularly between hospital and community pharmacists and their patients, may be a key mechanism.