Adverse drug effects in elderly people – a disparity between clinical examination and adverse effects self-reported by the patient

Abstract

The trend towards polypharmacy is increasing among the elderly, and associated with this trend is an increased risk of adverse drug effects and drug-drug interactions. Our objective was to assess whether drug adverse effects reported by patients are in general agreement with those identified by a physician. We evaluated the medication of 404 randomly selected individuals aged 75 years or older by means of interviews carried out by trained nurses and examinations conducted by a physician. The medication used by these patients was recorded prior to the physician's examination and modified thereafter if considered appropriate. Adverse effects noted by the physician were compared to those self-reported by the patients. Almost all of the patients (98.8%) were using at least one drug, and the mean total number of drugs used was 6.5. Adverse effects were self-reported by 11.4% of the patients, whereas the physician observed apparent adverse drug effects in 24.0% of the patients. No adverse effects were reported in 53.2% of the patients. There were only seven patients that had adverse effects that were both self-reported and identified by the physician, and only four of these patients reported the same adverse effect that had been identified by the physician. There was a great disparity between the adverse effects identified by the physician and those reported by the patients themselves. Based on our results, it would appear that elderly people tend to neglect adverse drug effects and may consider them to be an unavoidable part of normal ageing. Therefore, physicians should enquire about possible adverse effects even though elderly patients may not complain of any drug-related problems.