Adverse drug events in general practice patients in Australia
Objectives: To investigate the occurrence of adverse drug events in general practice and the cause and severity of these events.
Methods: Between May 2003 and February 2004, a sub-sample of 282 GPs in the BEACH data collection program recorded patient responses to questions about adverse drug events. Main outcome measures: Frequency, cause and severity of adverse drug events; frequency of hospitalisation; and frequency with which the GP believed events preventable.
Principal findings
From a total of 8,215 encounters, GPs reported that 852 patients (10.4%) had experienced an adverse drug event in the previous six months. Patients aged 45–64, 65–74 and 75+ were significantly more likely to have experienced an adverse drug event than younger patients. Children aged 1-4 had a significantly higher frequency of events than older children. Female patients were significantly more likely than male patients to have a adverse drug event. The majority (83.5%) had experienced only one adverse event, with 10.7% and 5.8% experiencing two and three or more events respectively. From a list of 9 reasons, only one was specified for the most recent adverse event for 89.7% of patients. The most frequently specified reason was a recognised side effect (65.7%), followed by drug sensitivity (11.8%) and allergy (11.0%). Over half of patients were rated as having a ‘mild’ event, with another 35.8% rated as ‘moderate’, and 10% as severe. GPs classified 23.2% of the events as preventable. Hospitalisation resulted from 7.6% of events.
Discussion and implication
Our proliferating pharmacopoeia of increasingly powerful and effective drugs has a corollary of increased risk to patient safety. Quantifying and evaluating this risk is essential to the improvement of patient safety. This study demonstrates the high frequency of ADEs in patients attending general practice.
(Note: Some of the data being presented in this paper will be published in the MJA - probably in April 2006)