Mortality prediction by Carotid Intimal Medial Thickness with a novel Life Table Statistical Model

Carotid Intimal Medial Thickness (CIMT) is an ultrasound estimate of preclinical atherosclerosis. The Charlottesville CIMT trial entered 1470 subjects from 1995 to 2011 and assessed total mortality in 2024 with a mean 15-year follow-up. In those subjects who reported no smoking or coronary disease, Cox statistics revealed that the presence of plaque and 4 th quartile common, bulb and internal CIMT measurements predicted total mortality (compared to the 1 st quartile). Age-normalized CIMT quartiles were less predictive. The age of subjects in the 4 th quartile was 15 years higher than the 1 st quartile. To correct for different ages, a novel life table model was created to analyze clinical data from a cohort who entered a trial at varying ages. This life table model allowed inclusion of subjects lost to follow-up. With this life table model, age-normalized 4 th and 3 rd quartile common, bulb and internal CIMT predicted total mortality. These data show the utility of measuring CIMT to predict mortality and the benefit of the life table model. The output statistic of the life table model, Age Difference, is an easily understandable and relevant measure of effect size.