Nutr J. 2025 Dec 13. doi: 10.1186/s12937-025-01267-6. Online ahead of print.
ABSTRACT
BACKGROUND: The association between relative fat mass (RFM), a sex-specific adiposity index derived from waist circumference and height, and incident cardiovascular diseases (CVDs) remains underexplored in Chinese populations. This study aimed to evaluate the predictive value of RFM for CVD risk in Chinese adults, addressing a gap in evidence for Asian cohorts with unique adiposity patterns.
METHODS: We analyzed 7,027 adults agedā„45 years without baseline CVD from the China Health and Retirement Longitudinal Study (CHARLS, 2011-2020). RFM was calculated using validated sex-specific equations. Cox regression models assessed RFM-CVD associations, with comprehensive subgroup analyses conducted to evaluate effect modification. The incremental predictive value of RFM beyond conventional Framingham risk factors was evaluated using area under the curve (AUC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI).
RESULTS: Over a median 9-year follow-up, 24.6% participants developed CVDs. Each 1-unit RFM increase conferred a 3% higher CVD risk (adjusted HR=1.03, 95% CI: 1.02-1.05). Participants in the highest RFM quartile had 46% greater CVD risk versus the lowest quartile (adjusted HR=1.46, 95% CI: 1.05-2.03; P-trend=0.004). Sex-stratified analyses revealed consistent associations in both genders, though stronger effects were observed in males. Subgroup analyses confirmed robust associations across age groups and those without comorbidities. RFM significantly improved CVD prediction when added to Framingham risk factors (AUC 0.640 vs. 0.634; NRI=0.140, IDI=0.004; P<0.001).
CONCLUSIONS: Higher RFM independently predicts incident CVDs in Chinese adults and enhances conventional risk stratification. RFM represents a practical anthropometric index for CVD prevention in clinical and public health settings, particularly valuable for resource-limited environments.
PMID:41390412 | DOI:10.1186/s12937-025-01267-6

