Johnson, AdedoyinKnapp, Shannon M.Mwansa, HunterQuintero Bisonó, JaninaBolakale-Rufai, Ikeoluwapo KendraMoore, WandaYankah, EkowYee, RyanTrabue, DalanceeWilliamson, FrancescaPool, NatalieHebdon, MeganCapers, QuinnBlount, CourtlandKimbrough, NiaJohnson, DeneeEvans, JalynnForee, BrandiHolman, Rev AnastasiaBrown, DavidTucker Edmonds, BrownsyneNallamothu, BrahmajeeHollingsworth, JohnBreathett, Khadijah2025-08-082025-08-082025-07-18Johnson A, Knapp SM, Mwansa H, et al. Relationship Between Hospital Team Segregation Index, Heart Failure, and Ischemic Heart Disease. JACC Adv. Published online July 18, 2025. doi:10.1016/j.jacadv.2025.101988https://hdl.handle.net/1805/50122Background: The extent of structural racism in cardiovascular care is not well studied. Objectives: The purpose of this study was to determine whether hospital segregation index (SI) (degree of dissimilarity between teams caring for Black vs White patients) is associated with receipt of a cardiologist's care, readmission up to 30 days, and 1-year survival for Black vs White patients admitted with heart failure (HF) or ischemic heart disease (IHD). Methods: Using Optum's Clinformatics Data Mart, we examined the effect of hospital SI on Black and White patients admitted with primary diagnoses of HF or IHD from 2010 to 2018 using mixed effects models. Hospitals were grouped by SI tertile. Results: Overall, 119,272 patients (29.4% Black, 70.6% White) with HF and 183,165 patients (17.9% Black and 82.1% White) with IHD were analyzed. Across SI tertiles, Black patients with HF had lower odds of receiving a cardiologist's care compared to White patients. Across SI tertiles and cardiology care, there was no difference in the hazard of readmission by race, and odds of 1-year survival were higher for Black patients. Among patients with IHD, there was no difference in odds of receiving cardiology care between races across SI tertiles. Black patients not seen by cardiologists had 20% higher hazard of readmission at high SI hospitals (HR: 1.20; 95% CI: 1.00-1.44). Odds of 1-year survival were higher for Black patients (OR: 1.10; 95% CI: 1.04-1.17) seen by cardiologists in low SI hospitals. Conclusions: Among Black vs White patients, HF outcomes did not vary by SI tertiles. However, in IHD, SI impacted Black patients' risk of readmission and survival.en-USAttribution 4.0 InternationalCardiovascular outcomesCoronary heart diseaseHeart failureIschemic heart diseaseRacial disparitiesArticle