Immediate-type drug hypersensitivity and associated factors in a general population.

BACKGROUND Our aim was to assess the prevalence and associated risk factors of common hypersensitivity reactions to drugs in the adult population, for which limited data are available. METHODS The data consisted of 1052 questionnaires obtained from adults. The questionnaires consisted of questions on immediate-type hypersensitivity reactions induced by drugs (itching, skin rash/hives, angio-oedema, shortness of breath, hypotension, and loss of consciousness). The questionnaire added knowledge on physician's diagnosis of asthma, allergic rhinitis, eczema, and other chronic systemic diseases. RESULTS The prevalence of self-reported drug hypersensitivity reactions was 11.8% for all reactions. Hypersensitivity reactions to analgesics were the most common (37.2%) followed by antibiotics (24.2%). Multivariate analysis showed that female gender (Odds Ratio (OR) 95% Confidence Interval (CI) (2.00 (1.25-3.21)), physician-diagnosed allergic rhinitis (3.03 (1.64-5.59)), and eczema (3.22 (1.87-5.53)) were associated with any type of drug hypersensitivity reactions. Itching was associated with allergic rhinitis (4.50 (2.06-9.81)) and eczema diagnosis (4.24 (2.14-8.64)). Skin rash/hives were associated with female gender (2.67 (1.24-5.74)), allergic rhinitis (4.57 (1.99-10.05)), and eczema (5.36 (2.65-10.84)). Angio-oedema was higher in females (5.74 (1.69-18.5)). In addition, eczema (2.87 (1.12-7.32)) and systemic hypertension (2.60(1.03-6.10)) were associated with angio-oedema. Shortness of breath was only associated with ever asthma diagnosis (6.59 (2.09-20.83)). Factors associated with loss of consciousness were female gender (5.56 (1.27-24.30)), allergic rhinitis diagnosis (4.76 (1.73-13.14)), and systemic hypertension (2.74 (1.02-7.41)). CONCLUSION The study showed that females and subjects with allergic diseases and hypertension were more susceptible to drug hypersensitivity reactions.