Sex-specific frailty and chronological age normative carotid artery intima-media thickness values using the Canadian longitudinal study of aging

Abstract

Objectives: Carotid intima-media-thickness (cIMT) is predictive of future cardiovascular events, increases with chronological age, and greater in males. The accumulation of health deficits (or frailty) is a marker of biological age. However, normative cIMT values are lacking and would be an important comparative tool for healthcare providers and researchers. This study aimed to establish sex-specific normative cIMT values across chronological age and frailty levels (i.e. biological age). Methods: Frailty and right common cIMT data were extracted from the Canadian Longitudinal Study of Aging baseline comprehensive cohort of middle-aged and older adults (n = 10,209; 5000 females). cIMT was assessed via high-resolution ultrasound. Frailty was determined using a 52-item frailty index. Ordinary least squares and quantile regressions were conducted between age (years or frailty index) with cIMT (average or maximum), separately for males and females. Results: In both sexes, average and maximum cIMT increased with higher chronological age and frailty. Both cIMT metrics increased non-linearly (quadratic-cIMT term) with advancing age (β-coefficients for quadratic and linear terms: all, p < 0.001), except for the linear relationship between average and maximum cIMT with chronological age among males (p < 0.001). Sex-specific normative average and maximum cIMT values were established (1st–99th percentiles, 5% increments), separately for chronological and biological ages. Conclusions: This is the largest sample of adults to establish normative cIMT outcomes that includes older adults. The chronological age and frailty-related normative cIMT outcomes will serve as a useful resource for healthcare professionals and researchers to establish “normal” age- and sex-specific cIMT values.