Objective: To quantify and evaluate drug utilisation in a sample of Dutch nursing homes.
Methods: A retrospective analysis of computerised medication data of 2355 residents aged 65 years and over from six nursing homes in the Netherlands was performed. For each therapeutic drug group, the number of users was determined. The ten therapeutic groups used most frequently were investigated further. For these, patient characteristics, use of therapeutic subgroups, the average daily dosages and the chronicity of drug use were determined. Chronicity was expressed as the percentage of treatment days divided by the number of residents' days in the nursing home.
Results: During the study period, 89%, 77% and 56% of the study population used a drug from the anatomical therapeutic chemical (ATC) main group N (nervous system), A (alimentary tract and metabolism) and C (cardiovascular system), respectively. Eight of the ten therapeutic drug groups prescribed most frequently were used for more than 50% of the time. In particular, psycholeptic drugs, diuretics and laxatives were used chronically (83%, 81%, and 80% of the nursing home stay, respectively). Except for a few drug groups, such as laxatives and diuretics, the prescribed daily dosages were relatively low. Twenty-eight percent of the residents received loop diuretics; these were prescribed in relatively high dosages.
Conclusion: Drug utilisation in the nursing homes was high and many drugs were used chronically. In view of the risk of possible adverse effects and drug-drug interactions, the prescribing and dosage of psycholeptic drugs, laxatives, loop diuretics and ulcer-healing drugs should be re-evaluated, carefully.