The obesity paradox in colon cancer hospitalizations: Mortality and cardiovascular risk.

Abstract

e15716 Background: Obesity is a well-established risk factor for colorectal cancer (CRC) and is associated with adverse oncologic outcomes, including increased postoperative morbidity. Proposed mechanisms include adipose tissue–mediated chronic inflammation, insulin resistance, altered adipokine signaling, and gut microbiome dysregulation, all of which may influence tumor biology and clinical outcomes. Despite these associations, an “obesity paradox,” characterized by lower short-term mortality among patients with obesity, has been reported in several oncologic populations. However, data evaluating this phenomenon in hospitalized patients with colon cancer remain limited, particularly with respect to cardiovascular complications and healthcare utilization. This study aimed to evaluate the association between obesity and in-hospital outcomes among patients hospitalized with colon cancer. Methods: A retrospective cohort study was conducted using the 2019–2022 National Inpatient Sample (NIS) database. Adult patients (≥18 years) hospitalized with colon cancer were identified using ICD-10 codes and stratified by the presence of obesity. The primary outcome was in-hospital mortality. Secondary outcomes included race, length of stay (LOS), hospital charges, cardiovascular diseases, and other clinical outcomes. Results: A total of 1,026,965 hospitalizations for colon cancer were identified, of which 143,255 (13%) involved patients with obesity. In-hospital mortality among obese patients was 3,850 (2.7%). Obese patients were more commonly White (72%), had a mean age of 66 years, and demonstrated significantly lower in-hospital mortality compared with non-obese patients (2.7% vs 4.8%; OR 0.55; P < 0.001). Obesity was associated with longer length of stay (coefficient 0.17; P < 0.001), higher hospital charges (coefficient $12,107; P < 0.001), a higher risk of diverticulitis (1.8% vs 1.4%; OR 1.28; P < 0.001), and increased cardiovascular complications, including arrhythmias (19% vs 16%; OR 1.20; P < 0.001) and acute heart failure (5% vs 3%; OR 1.50; P < 0.001), compared with non-obese patients. Conclusions: Among patients hospitalized with colon cancer, obesity was associated with lower in-hospital mortality, supporting the presence of an obesity paradox in the inpatient setting. However, obesity was also associated with increased healthcare utilization and a higher burden of cardiovascular complications. These findings highlight the complex impact of obesity on inpatient outcomes in colon cancer and underscore the importance of risk-stratification strategies that integrate oncologic, metabolic, and cardiovascular factors.