A body shape index (ABSI) but not body mass index (BMI) is associated with prostate cancer-specific mortality: Evidence from the US NHANES database.

ABSTRACT

BACKGROUND: Prostate cancer (PCa) is a common malignancy in males and obesity may play a role in its development and progression. Associations between visceral obesity measured by a body shape index (ABSI) and PCa mortality have not been thoroughly investigated. This study assessed the associations between ABSI, body mass index (BMI), and long-term PCa-specific mortality using a nationally representative US database. METHODS: This population-based longitudinal study collected data of males aged ≥40 years diagnosed with PCa and who underwent surgery and/or radiation from the National Health and Nutrition Examination Survey database 2001-2010. All included participants were followed through the end of 2019 using the National Center for Health Statistics Linked Mortality File. Associations between PCa-specific mortality, BMI, and ABSI were determined using Cox proportional hazards regression and receiver operating characteristic (ROC) curve analysis. RESULTS: Data of 294 men (representing 1,393,857 US nationals) were analyzed. After adjusting for confounders, no significant associations were found between BMI (adjusted hazard ratio [aHR] = 1.06, 95% confidence interval [CI] 0.97-1.16, p = 0.222), continuous ABSI (aHR = 1.29, 95% CI 0.83-2.02, p = 0.253), or ABSI in category (Q4 vs. Q1-Q3 aHR = 1.52, 95% CI 0.72-3.24, p = 0.265), and greater risk of PCa-specific mortality. However, among participants who had been diagnosed within 4 years, the highest ABSI quartile but not in BMI was significantly associated with greater risk for PCa-specific mortality (Q4 vs. Q1-Q3 aHR = 5.34, 95% CI 2.26-12.62, p = 0.001). In ROC analysis for this subgroup, the area under the curve of ABSI alone for predicting PCa-specific mortality was 0.638 (95% CI 0.448-0.828), reaching 0.729 (95% CI 0.490-0.968 when combined with other covariates. CONCLUSIONS: In US males with PCa diagnosed within 4 years, high ABSI but not BMI is independently associated with increased PCa-specific mortality.