Prevalence of clinically relevant drug-drug interactions in Cardiac
Intensive Care Units in tertiary care hospitals in the United States and
Objective To determine the prevalence of clinically relevant drug-drug
interactions in an intensive care unit of a tertiary care hospital in
the United States and to compare to an intensive care unit at a
Pakistani hospital, which lacks electronic medical record-based
drug-drug interaction screening. Study setting A retrospective
cross-sectional analysis was conducted in the cardiovascular intensive
care unit (CVICU) at Michigan Medicine (MM), Ann Arbor, MI, USA between
Jan 2018 – Jan 2019. Study Design Analysis of 300 MM patients was
conducted to identify drug-drug interactions using Micromedex® and
Lexicomp®. Descriptive statistics and multivariate binary logistic
regression was used. Independent samples t-test was used to compare
prevalence between MM and in a similar cohort of patients in the cardiac
intensive care (CCU) at KTH, Pakistan from a previously published study.
Data Collection Data was collected for patients who were admitted to the
CVICU for at least 24 hours and were prescribed at least 2 drugs from
the electronic health record of MM. Principal Findings In the intensive
care unit of the US hospital, 58% of patients had at least one
drug-drug interaction, while 16% had a clinically relevant drug-drug
interaction. Significantly fewer patients had drug-drug interactions at
the US hospital than the Pakistani hospital (58% vs. 95%, p
< 0.01). Polypharmacy and length of stay increased drug-drug
interaction occurrence in the US hospital (p <0.01).
Conclusion The prevalence of drug-drug interactions in the intensive
care unit at the US hospital was high but lower than the Pakistani
hospital, likely due to electronic medical record-based screening.
Despite electronic medical record-based screening at the US hospital, 8
clinically relevant drug-drug interaction pairs were undetected.