Association between resting heart rate and all-cause mortality in patients with intracerebral hemorrhage in the intensive care unit: a retrospective study based on the MIMIC-IV database

Background Intracerebral hemorrhage (ICH) is a leading cause of disability and mortality, accounting for 20-30% of acute cerebrovascular events. Resting heart rate (RHR) is an important vital sign linked to prognosis, particularly in cardiovascular diseases. This study investigates the association between RHR and all-cause mortality (ACM) in intensive care unit (ICU) patients with ICH. Methods Data were extracted from the MIMIC-IV database. Patients were divided into quartiles (Q1–Q4) based on RHR. ACM at 30 days, 90 days, and one year was assessed. Kaplan-Meier curves, multivariate Cox regression, and restricted cubic splines were used to analyze the relationship between RHR and ACM, with receiver operating characteristic curves evaluating the predictive value of RHR >90.3 beats per minute (bpm). Results A total of 1,918 patients were included. Survival curves showed significantly higher mortality in higher RHR quartiles (Q3 and Q4) compared to Q1 and Q2. Multivariate Cox regression confirmed that RHR above the second quartile (RHR=78.5 bpm) was linked to higher mortality. Restricted cubic splines revealed a nonlinear relationship between elevated RHR and increased mortality. Conclusions A resting heart rate below 90.3 bpm may serve as an independent protective factor against all-cause mortality in patients with intracerebral hemorrhage in the intensive care unit. In contrast, an elevated resting heart rate exceeding 90.3 bpm may be independently associated with an increased risk of all-cause mortality in this population.