[Adverse drug effects: a prospective study by Apnet performed in seven emergency care units in France: propositions for preventive measures].

Various studies have shown that adverse drug effects (ADEs) are a substantial cause of hospital admissions. However, little is known about the incidence and severity of ADEs resulting in hospital visits. To address this issue, we conducted a prospective survey in primary care and emergency departments of French public hospitals. This study was performed over two periods of one week, one in January, February and one in June 2003, in primary care and emergengy departments of four university hospitals and three general hospitals throughout France. Out of a total of 1826 patients consulting, 1663 were taking at least one drug during the previous week and were included for analysis according to the protocol. Altogether, 370 (22.2%; IC 95: 20.2-24.3%) of these patients receiving at least one drug consulted because of an ADE. From these 370 patients, 263 (15.8%) where considered as touched by a probably (12), likely (13) or very likely (14) ADE. The sex ratio was the same in both groups with or without ADE (0.88%; P=0.95). Patients with ADE were older than those without (62.4 vs 53.8 years, P=0.0016). Furthermore, ADE patients were more likely to have a higher severity score than no-ADE group (P=0.0003). The outcome seemed to be worse in patients with an ADE. The percentage of patients treated with 2 or more drugs and the number of drug exposures were significantly higher in patients with ADE than in those without (93.2% vs 84.2%, P<0.0001, and 5.8 vs 4.5 P<0.0001, respectively). The most frequent causes of visits for ADE-patients were digestive (n=38: 14.4%), neurological (n=23: 10.6%), malaise (n=48: 18,2%) events. The most frequently incriminated drug classes were (1) psychotropic agents, (including anxiolytics, hypnotics, antidepressants and antipsychotics), (2) diuretics (3) anticoagulants, (4) other cardiovascular drugs and (5) analgesics, including non steroidal anti-inflammatory agents. In 150 cases (40.8%; IC 95: 33.7% - 45%), the ADE was considered to be preventable because a contra-indication or a warning about drug use had not been respected.