[Factors associated with the occurrence of adverse reactions to drugs in patients who went to the emergency service of a general hospital: a case-control study].

OBJECTIVE

To describe adverse reactions to medicine (ARM) and analyse the factors associated with their presenting in patients attending a general hospital's emergency service.

DESIGN

Case-control epidemiological study.

SETTING

Emergency service of the San Cecilio University Hospital in Granada.

PATIENTS: 654 patients over 15, men and women, who attended the emergency service between October and December 1997. 354 of them had an ARM (cases) and 300 did not (controls).

MEASUREMENTS AND

RESULTS

60% of the cases were women, with an average age of 53 +/- 20. 68% of the ARM were type-A (expected). The most affected organs and systems were: digestive tract (41.8%) and skin (31.6%). Drug groups most associated with presentation of ARM were hypnosedatives and salicylates used as analgesics--antithermic drugs (28.2%), and beta-lactams and macrolides (22.6%). Most ARM were classified as probable (52%) and moderate (62%). Family practitioners were the main prescribers (49%) of medicines. 13% of patients were admitted to hospital because of a serious ARM and two people died (0.5%). According to the odds ratio, treatment with cytostatics, psychiatric drugs, NSAIDs, amoxycillin, digoxin, ACEIs and calcium antagonists, being a woman, self-medication, being under 65 and history of ARM were all associated with the presence of an ARM in our patients (cases).

CONCLUSIONS

The type of medicine, being a woman, history of ARM, self-medication, and presenting digestive and dermatological symptoms were factors strongly linked to an ARM in patients attending the emergency service.