Care utilization and inpatient mortality among women younger than 50 years hospitalized with breast cancer: Racial and socioeconomic disparities.

e13757 Background: Racial and socioeconomic disparities in breast cancer outcomes are well recognized, but it remains unclear whether these inequities are evident at the time of hospital presentation. Women aged less than 50 years represent a distinct subgroup as they are presumed healthier with a lower co-morbidity burden. We conducted a retrospective cross-sectional analysis to evaluate whether racial and socio-economic status are associated with illness severity and need for ICU-level care among hospitalized women with breast cancer younger than 50 years. Methods: A retrospective cross-sectional analysis of the 2018–2022 National Inpatient Sample was conducted. Adult women younger than 50 years hospitalized with a principal diagnosis of breast cancer were identified. The primary outcome was ICU-level care, defined as a composite of mechanical ventilation, shock, or extreme APR-DRG severity. Secondary outcomes included in-hospital mortality, length of stay (LOS) and hospitalization cost. National estimates accounted for NIS stratification, clustering, and discharge-level weighting to generate nationally representative estimates. Multivariable survey-weighted logistic regression assessed associations of race, insurance status, and ZIP-code income quartile with ICU utilization and mortality, adjusting for age, year, elective admission and hospital characteristics. Race-by-insurance interactions were explored using collapsed payer categories to address sparse cells. Results: The cohort included 8,129 unweighted hospitalizations, representing 40,645 weighted admissions nationally. Overall ICU composite utilization was 2.6% (95% CI 2.3–3.0). ICU use varied by race (White 1.4%, Black 3.4%, Hispanic 2.2%, Asian/Pacific Islander 2.1%), insurance (private 2.1%, Medicare 5.0%, Medicaid 3.3%) and neighborhood income (lowest vs highest quartile: 4.0% vs 1.0%). In adjusted analyses, Asian/Pacific Islander women had higher odds of ICU-level care compared to White women (OR 2.18, 95% CI 1.05–4.54), while residence in the highest income quartile was protective (OR 0.45, 95% CI 0.24–0.82). Overall in-hospital mortality was 2.2% but was substantially higher among hospitalizations meeting ICU composite criteria (28.3% vs 1.5%). After adjustment, ICU-level care was the strongest predictor of mortality (OR 8.69, 95% CI 4.99–15.13). Mortality also demonstrated racial and socioeconomic gradients. Conclusions: Among women younger than 50 years hospitalized with breast cancer, racial and socioeconomic disparities are evident at the point of hospital presentation, reflected by differential need for ICU-level care. ICU utilization identifies a small but extremely high-risk subgroup with markedly elevated in-hospital mortality, highlighting severity at presentation as a critical and underrecognized dimension of cancer health equity.