LAUSR

INTRODUCTION One of the reasons for poor medication compliance among patients is the occurrence of adverse drug reactions. OBJECTIVES The aim of this study was to determine the prevalence of Multiple Drug Intolerance Syndrome, defined as adverse reactions to 3 or more classes of drug, among patients with arterial hypertension, and to assess the predisposing factors. PATIENTS AND METHODS The study population comprised hospitalized patients diagnosed with arterial hypertension as well as patients undergoing chronic treatment in an outpatient hypertension clinic. The authors used a structured proprietary questionnaire, which focused on demographic and clinical data, including current or past history of adverse drug reactions. RESULTS The study population comprised 1000 patients, including 560 women.  The mean (SD) age was 62.8 (14.9) years. Eighty patients (8%) suffered from MDIS. Among MDIS patients, as compared to the remaining subjects, there were more women  (71% vs. 55%, P = 0.01). Patients with MDIS had longer history of hypertension (median 15  vs. 10 years, P = 0.01) and were more likely to suffer from respiratory (P = 0.01), gastrointestinal (P = 0.003), rheumatoid (P <0.001) and endocrine (P = 0.01) disorders. The risk of MDIS was highest with the concomitant use of analgesics, followed by beta-blockers, antiplatelet drugs and antibiotics. CONCLUSIONS MDIS in patients with hypertension is common and more frequently affects women and patients with a longer known disease duration. Comorbidities increase the risk of MDIS. The risk of MDIS is strongly associated with the use of analgesics, beta-blockers, antiplatelet drugs and antibiotics.