Point prevalence of drug prescriptions for elderly and non-elderly inpatients in a teaching hospital

CONTEXT: Age-related pharmacokinetic and pharmacodynamic changes have been extensively documented, and several concurrent diseases may underlie multiple drug therapy in the elderly. As a result, the risk of adverse drug reactions and drug interactions increases among aged patients. However, only a few studies have compared the prescribing patterns for different age groups of hospitalized patients or have evaluated the effect of age on drug prescription. OBJECTIVE: To compare the prevalence of drug prescriptions for elderly inpatients, with those for non-elderly inpatients, in order to assess age-related differences in the number of prescribed drugs, drug choices and prescribed doses, and to evaluate the prescription appropriateness for the elderly patients. TYPE OF STUDY: Cross-sectional survey. SETTING: 400-bed tertiary care general teaching hospital. PARTICIPANTS: All inpatients on one day of June 1995, except for the Intensive Care Unit and for the Departments of Psychiatry, Pediatrics and Obstetrics and Gynecology. PROCEDURES: All medicines prescribed to the eligible patients on the study day were recorded from the prescription sheets provided by the hospital pharmacy. MAIN MEASUREMENTS: Name, therapeutic class, and mean daily dose of the prescribed drugs. RESULTS: Of the 273 eligible inpatients, 46.5% were 14-44 years old, 33% were 45-64 years old and 20.5% were > 64 years old. Cancer was significantly more frequent among the elderly. The mean number of prescribed drugs was five for all age groups. The five most prescribed drugs for all patients were dipyrone, ranitidine, dipyrone in a fixed-dose combination, metoclopramide and cefazolin. The elderly had significantly more prescriptions for insulin, furosemide and enoxaparin. For most drugs, the mean prescribed dose showed that there was no dose adjustment for elderly patients, and drug choices for this age group were sometimes questionable. CONCLUSIONS: There was little variation in the prescribing patterns for the elderly when compared with the other age strata