Retrospective analysis of adverse side-effects of medication in elderly patients at a primary care health centre

To describe the adverse drug events (ADEs) reported by doctors of a primary health care centre in the patient's medical record. A retrospective, descriptive study. Burriana Health Centre (Castellón), Spain. All patients over 75 with a clinical history held on paper at the health centre, ie non-institutionalized patients seen on an out-patient basis, were checked. A total of 2044 paper-based medical records were analysed, in which 832 histories describing 1893 ADEs (90.4% unforeseen and 9.6% preventable) were found. This means that 41% of the patients experienced one or more adverse events, with an average of 2.28 ADEs per patient. Most ADEs (85.3%) were light, but 6% were classified as serious, with high digestive haemorrhage caused by NSAIDs standing out as the most common serious problem (37.3%). The pharmaco-therapeutic groups most involved in ADEs were cardiovascular therapy (29.4%), anti-infectious drugs (21.2%) and nervous system drugs (20.1%). Seventeen cases of intoxication were detected (0.9% total ADEs), with digoxin responsible for 67% of the serious intoxications. It was observed that ADEs occur with statistical significance most frequently in women (OR, 1.73; 95% CI, 1.42-2.10). After an age-stratified analysis, it was concluded that the only sub-group where the increase in risk was not significant was the group of people over 85 years old. ADEs create a serious public health problem, with negative effects on patients. Although most ADEs are unforeseen (90.4%), it is still worrying that 9.6% of the ADEs identified are preventable.