Objectives: To study the incidence and to evaluate the risk factors of suspected adverse drug reactions developed in the hospitalized patients of various departments and to assess the causality and severity of adverse drug reactions (ADRs). Methods: It was a retrospective-prospective study conducted in a tertiary care hospital for a period of two years two months, with a specific predefined criterion. A total of 254 subjects with ADRs were identified during the period of study for which 1:1 ratio of subjects with non-ADRs were taken. Subjects of all age groups and of either sex were enrolled. Risk factors included subjects’ age group, gender, polypharmacy, comorbidity, intercurrent diseases and concurrent interactive drugs. Statistical analysis used: Multiple logistic regression analysis was performed to find the association of risk factors with adverse drug reactions. Results: The incidence of suspected adverse drug reactions in hospitalized patients was13% (254/1952, 95%CI). Polypharmacy was the most significant predictor of adverse drug reactions (OR=55.952; 95%CI). Elderly population with multidrug therapy had developed the higher rate of ADRs. Cephalosporin’s 27.6%, fluoroquinolones 15.5%, penicillamines 12.1%, anti-hypertensive 8.7%, NSAIDs 8.3% were more frequently implicated. Risk factors for suspected ADRs were: age (more than 60 years) (OR=1.033: 95% CI), gender [Male (OR=55.952; 95% CI)], comorbidity (OR=1.008; 95% CI), intercurrent diseases (OR=19.27; 95% CI). Conclusion: Polypharmacy, history of ADR, concurrent interactive drugs and inter current disease were the significant risk factors of adverse drug reactions. The elderly population was the vulnerable age group for ADRs. Multidrug therapy and comorbidity resulted in higher risk of ADRs in an older population. The Higher rate of suspected ADRs were probable and very less severe.
Key words: Adverse drug reaction, Age, Comorbidity, Polypharmacy, Risk factor.