Publication:

Characteristics, determinants and cost implications of severe adverse drug reactions in the intensive coronary care unit of a hospital

Background The objective of the study was to determine the predictors, frequency, characteristics and incremental costs of severe Adverse Drug Reactions in the Intensive Coronary Care Unit (ICCU) of a hospital.

Methods Two trained physicians prospectively reviewed case records of all in-patients admitted to ICCU over one year (July 2015 to June 2016) and identified ADRs. Each ADR was assessed for causality, severity, predictability and preventability. Determinants of severe ADRs were identified using multiple binary logistic regression analysis. Cost of severe ADR was estimated based on the corrected duration of excess hospital stay after adjusting for age, gender, co-morbid conditions and number of drugs.

Results Of 573 cases admitted during one year, 47 (8%) patients had 56 severe ADRs. Streptokinase (16.1%) was the commonest drug associated with severe ADRs. Arrhythmias (30.4%) were the commonest severe ADR. Presence of arrhythmias (OR 4.54, 95% CI 2.25–9.14), renal dysfunction (OR 2.27, 95% CI 1.01–5.11) and poly-pharmacy (>10 drugs) (OR 1.13, 95% CI 1.007- 1.254) were found to be the predictors for occurrence of severe ADRs. Majority of severe ADRs were found to be probable 30 (53.6%). 46 (82%) were predictable and 25 (44.6%) probably preventable severe ADRs. Patients with severe ADRs had a longer duration of ICCU (0.8 extra day) and hospital stay (1.5 extra days) (adjusted analysis). The mean incremental cost incurred by patients in the severe ADR group was $ 32 (INR 2170/-) per patient based on the corrected duration of hospital stay.

Conclusions Severe ADRs in ICCU add considerably to treatment costs. Cardiac arrhythmias, renal dysfunction, and polypharmacy are important predictors of severe ADRs.