Association of Initial Laxative Strategy With Clinical Outcomes in Critically Ill Patients With Acute Myocardial Infarction: A Retrospective Cohort Study

Abstract

Background

Although laxatives are commonly used for constipation in critically ill patients with acute myocardial infarction (AMI), the optimal initial choice is unclear. We are aimed at comparing the clinical outcomes of initiating therapy with stimulant, stool softener, and osmotic laxatives.

Methods

This retrospective study analyzed ICU patients with AMI from the MIMIC-IV database, comparing three initial laxative strategies using propensity score matching (PSM). The primary outcome was 28-day mortality. Secondary outcomes included ICU, in-hospital, and 365-day mortality; cardiogenic shock; malignant arrhythmia; delirium; and bowel sound recovery. Findings were validated with inverse probability of treatment weighting (IPTW) and subgroup analyses.

Results

In the 1:1:1 PSM cohort of 1887 patients, stool softeners were associated with significantly lower mortality versus stimulants: in-hospital (adjusted OR = 0.39, 95% CI 0.22–0.69, p = 0.001), 28-day (aHR = 0.55, 95% CI 0.40–0.76, p < 0.001), and 365-day (aHR = 0.57, 95% CI 0.45–0.72, p < 0.001). Osmotic laxatives correlated with lower in-hospital (aOR = 0.52, 95% CI 0.30–0.89, p = 0.017) and 28-day (aHR = 0.72, 95% CI 0.55–0.95, p = 0.019) mortality, but not 365-day compared with stimulant laxatives. Both agents were linked to lower delirium risk and better bowel sound recovery. IPTW sensitivity analyses showed consistent results.

Conclusion

Among ICU-admitted AMI patients, the initial use of stool softeners or osmotic laxatives was associated with a lower risk of short-term mortality compared with stimulant laxatives. These findings indicate that a more robust and gentle laxative management strategy may have potential clinical value for this high-risk population.