Impact of body mass index on changes in common carotid artery wall thickness.

OBJECTIVE: To examine associations between changes in body mass index (BMI) and changes in carotid artery intima-media thickness (IMT) in a community-based sample.

RESEARCH METHODS AND PROCEDURES: Carotid artery IMT and BMI were assessed at baseline (between 1987 and 1990) and in three subsequent examinations at 3-year intervals in participants in the Atherosclerosis Risk in Communities cohort. The 9,316 African-American and white men and women in the analysis were 45 to 64 years of age at baseline. Cross-sectional associations between BMI and IMT were assessed using general linear models. Longitudinal associations were examined using mixed models analysis.

RESULTS: Cross-sectional associations between BMI and IMT were confirmed. At baseline, a 1-kg/m(2) increase in BMI was associated with an increase in IMT that ranged from 2.5 to 7.5 micro m among the ethnic-gender groups examined. Changes in BMI were not associated with changes in IMT in models that adjusted for aging and other covariates. Results were similar across ethnic-gender groups.

DISCUSSION: Among free-living, 45- to 64-year-old adults, changes in common carotid artery IMT associated with changes in BMI are either very small or absent.