Risk factors associated with aortic and carotid intima-media thickness in adolescents and young adults: the Muscatine Offspring Study

Abstract

Objectives: This study sought to determine whether cardiovascular risk factors are associated with aortic intima-media thickness (aIMT) and carotid intima-media thickness (cIMT) in adolescents and young adults.

Background: Atherosclerotic lesions begin developing in youth, first in the distal abdominal aorta and later in the carotid arteries. Knowledge of how risk factors relate to aIMT and cIMT may help in the design of early interventions to prevent cardiovascular disease.

Methods: Participants were 635 members of the Muscatine Offspring cohort. The mean aIMT and cIMT were measured using an automated reading program.

Results: The mean (SD) values of aIMT and cIMT were 0.63 (0.14) and 0.49 (0.04) mm, respectively. In adolescents (age 11 to 17 years), aIMT was associated with triglycerides, systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), and waist/hip ratio, after adjusting for age, sex, and height. In young adults (age 18 to 34 years), aIMT was associated with those same 5 risk factors, plus high-density lipoprotein cholesterol and pulse pressure. In adolescents, cIMT was associated with SBP, pulse pressure, heart rate, BMI, and waist/hip ratio. In young adults, cIMT was associated with total cholesterol, low-density lipoprotein cholesterol, triglycerides, SBP, DBP, BMI, waist/hip ratio, and glycosylated hemoglobin. In both age groups, aIMT and cIMT were significantly correlated with the Pathobiological Determinants of Atherosclerosis in Youth coronary artery risk score.

Conclusions: Both aIMT and cIMT are associated with cardiovascular risk factors. Using aIMT in adolescents gives information beyond that obtained from cIMT alone. Measurement of aIMT and cIMT may help identify those at risk for premature cardiovascular disease.

Figure 1. Boxplots showing distributions of aIMT and cIMT for adolescents and young adults

Box heights show inter-quartile ranges (IQR). Vertical capped lines (a.k.a., “whiskers”) extend to most extreme data points within 1.5IQR of boxes. Data further than 1.5IQR from boxes are plotted individually.