Age- and Sex-Specific Patterns of Arterial Stiffness Assessed by Cardio-Ankle Vascular Index in Apparently Healthy...

Objective: This study examined age- and sex-specific correlates of arterial stiffness, assessed by the cardio-ankle vascular index (CAVI), in apparently healthy Chinese adults using an anthropometric-metabolic-inflammatory framework, and descriptively compared subgroup association patterns across these domains. Methods: In this cross-sectional study, 525 apparently healthy Chinese adults aged 20-78 years were included. Regression models with age-by-indicator interaction terms were used to test whether the age-CAVI association varied across anthropometric, metabolic, and inflammatory indicators. Sex-adjusted analyses were applied to the overall sample, sex-stratified analyses were used to characterize sex-specific patterns, and the Benjamini-Hochberg false discovery rate correction was applied for multiple interaction tests. Results: CAVI increased progressively with age, with a steeper age-CAVI association after 50 years (p < 0.05). Notably, females showed a transient midlife elevation. Association patterns appeared to differ by sex. In the sex-stratified interaction analyses, anthropometric signals were more prominent in men, particularly for height (p < 0.01), whereas metabolic-related interaction signals were more evident in women, with triglycerides providing the clearest corresponding signal and low-density lipoprotein cholesterol (LDL-C) showing a weaker accompanying pattern; the C-reactive protein (CRP)-related contrast was not retained after additional adjustment for blood pressure and smoking. Conclusions: CAVI increased with age, with a steeper rise after midlife and a transient midlife elevation in women. The association patterns across anthropometric, metabolic, and inflammatory indicators appeared to differ by sex, with signals from the anthropometric domain appearing more evident in men and metabolic-related signals appearing more evident in women. These findings suggest that age- and sex-specific interpretation of CAVI may be informative in preventive health check-up settings.