Influence of cardiovascular co-morbidities on the in-hospital mortality among patients with sickle cell crisis

Using the US National Inpatient Sample, we analyzed 424,540 adult hospitalizations for sickle cell crisis (SCC) from 2016–2020 to quantify cardiovascular comorbidities and their associations with in-hospital mortality. The cohort (mean age 32.4 years; 55.4% female) was predominantly Black (93.0%) and socioeconomically disadvantaged (51.1% lowest income quartile); most admissions occurred at urban teaching hospitals (82.1%). Age showed a monotonic relation with mortality (multivariable HR per year 1.04, 95% CI 1.03–1.05). In adjusted models, six cardiovascular factors independently predicted higher mortality: systolic heart failure (HR: 2.0; 1.35–2.96), atrial fibrillation/flutter (HR: 1.58; 1.08–2.30), ischemic stroke (HR: 3.25; 1.85–5.71), right ventricular failure (HR: 3.14; 1.46–6.75), pulmonary embolism (HR: 5.61; 3.78–8.33) and acute coronary syndrome (HR: 3.70; 2.30–5.95) (All p<0.01). By contrast, chronic coronary artery disease was inversely associated with mortality (adjusted OR 0.41, 0.23–0.74, p<0.01), a paradoxical pattern that likely reflects index-event (collider) bias, treatment confounding, or differential specialty follow-up and warrants prospective adjudication. Compared with White patients, Black patients had lower adjusted in-hospital mortality (HR 0.44, 0.21–0.94, p = 0.03). Our findings prioritize thrombo-ischemic and rhythm/pump failure phenotypes as high-yield targets for risk stratification and crisis-time management, and they motivate integrated cardio-hematologic strategies and prospective validation.