Treatment-interrupting hospitalization as an acute oncologic toxicity in solid tumors.

Abstract

e23204 Background: Treatment-interrupting hospitalization (TIH) refers to unplanned admissions disrupting systemic cancer therapy. TIH reflects cumulative impacts of treatment toxicity, disease burden, frailty, and healthcare factors, associated with increased mortality, prolonged hospitalization, functional decline, and treatment disruption. Methods: The National Inpatient Sample (NIS), 2016–2022, was analyzed to construct a solid tumor cohort (ICD-10 malignant neoplasms C00–C80), excluding hematologic malignancies (C81–C96) and palliative encounters (Z51.5). The analytic cohort included 3,046,500 unweighted hospitalizations. TIH (core) was defined by any of the following: LOS ≥7 days, mechanical ventilation, shock (R57), sepsis or septic shock (A40/A41/R65.2), neutropenia (D70), major organ toxicities (AKI N17, acute respiratory failure J96, pneumonitis or ARDS J70/J80, venous thromboembolism I26/I80/I82), or frailty syndromes (malnutrition E43/E44/E46, cachexia R64, dysphagia R13*, pressure ulcer L89*, falls W0/W1/R29.6/Z91.81). A prespecified strict definition required LOS ≥10 days or ICU, mechanical ventilation, shock, sepsis, or neutropenia. Survey-weighted analyses used NIS weights, strata, and primary sampling units. Adjusted models included age, sex, year, race, payer, ZIP-code income quartile, elective admission, weekend admission, hospital region, number of beds, and teaching status. Results: TIH prevalence was 59.3% (95% CI 59.1–59.5); TIH (strict) was 27.0% (95% CI 26.8–27.1). Compared with non-TIH admissions, TIH admissions had higher crude mortality (4.32% [95% CI 4.26–4.37] vs 0.316% [95% CI 0.305–0.328]), longer LOS (7.80 days [95% CI 7.77–7.83] vs 2.85 days [95% CI 2.84–2.85]), and higher costs ($26,958 [95% CI $26,376–$27,540] vs $16,466 [95% CI $16,115–$16,817]). TIH admissions more often required airway escalation (5.84% [95% CI 5.79–5.90] vs 0.149% [95% CI 0.138–0.161]) and non-home discharge (54.38% [95% CI 54.14–54.63] vs 23.44% [95% CI 23.20–23.69]). In adjusted models, TIH (core) was strongly associated with inpatient mortality (aOR 13.58, 95% CI 12.99–14.20), airway escalation (aOR 50.19, 95% CI 46.35–54.35), increased LOS (+5.28 days, 95% CI 5.25–5.31), and higher costs (log-cost coefficient 0.709, 95% CI 0.701–0.716; approximately 2.03-fold increase). Sensitivity analyses using TIH (strict) yielded consistent associations with mortality (aOR 8.52, 95% CI 8.34–8.70), airway escalation (aOR 36.46, 95% CI 34.76–38.24), and LOS (+7.78 days, 95% CI 7.73–7.84). Conclusions: Treatment-interrupting hospitalizations are common among solid tumor admissions and identify hospitalizations with higher mortality, escalation of care, cost, and non-home discharge. Conceptualizing TIH as an acute oncologic toxicity provides a practical, reproducible framework to systematically identify severe inpatient events disrupting systemic therapy.