The Impact of Medication Regimen Complexity Score on Multi-Organ Dysfunction and Clinical Outcomes in Critically Ill Patients: A Cohort Study

Background Evidence is limited on the utilization of the Medication Regimen Complexity – Intensive Care Unit (MRC-ICU) scores for predicting clinical outcomes in critically ill patients. Therefore, this study aims to examine the impact of the MRC-ICU score on clinical outcomes for critically ill patients.Research design and methods A single-center retrospective cohort study included adult ICU patients admitted for >72 hours between January and December 2021. Patients were categorized into two groups based on MRC-ICU scores assessed within 24 hours of ICU admission. The primary endpoint was the Multiorgan Dysfunction (MOD) score at 72 hours of ICU admission. Other clinical outcomes were considered secondary.Results Of the 1406 patients included, 718 had an MRC-ICU score of nine or higher. Patients with MRC-ICU scores ≥9 had significantly higher MOD scores at 72 hours (median 5 vs 3, p < 0.001), longer hospital LOS, and higher mortality rates in crude analyses. Regression analysis showed a significant association between MRC-ICU score and MOD score at day 3 of ICU admission (coefficient: 0.49, 95% CI 0.07 to 0.92, p = 0.02). However, no significant differences were observed with ICU-LOS, vasopressor-free days, or mortality.Conclusions Higher MRC-ICU scores might be linked to worse clinical outcomes, including greater organ dysfunction, and longer hospital stay.