Abstract
Introduction:
Carotid intima-media thickness (cIMT) is a noninvasive measurement of early atherosclerosis by ultrasound. Determinants of cIMT in individuals without classical cardiovascular (CV) risk factors are poorly studied.
Hypothesis:
We assessed the hypothesis that systolic blood pressure (SBP), body-mass index (BMI), serum glucose and LDL cholesterol (LDL-c) are associated with maximal cIMT values in low-risk individuals (no hypertension, diabetes, dyslipidemia or prior CV disease, no CV medications, no current or past smoking and a BMI < 30 kg/m
2
).
Methods:
We used data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline. ELSA-Brasil is a multicenter cohort of 15,105 civil servants aged 35-74 years in six Brazilian cities. Baseline assessment included cIMT measurements in both common carotid arteries. SBP, BMI, serum glucose and LDL-c values were standardized. We used multiple linear regression models to study the association of SBP, BMI, serum glucose and LDL-c with maximal cIMT (in mm).
Results:
We analyzed 1,569 ELSA-Brasil low-risk participants with complete cIMT data. There were 1,024 (65.3%) women and 924 (58.9%) of White race. Mean ± standard deviation (SD) for continuous variables were: age 46.1 ± 7.7 years; SBP 111.2 ± 10.8 mmHg; BMI 24.0 ± 2.9 kg/m
2
; serum glucose 99.7 ± 7.8 mg/dl; LDL-c 105.6 ± 17.1 mg/dl and maximal cIMT 0.700 ± 0.136 mm. The table shows the beta-coefficients associated to one standard deviation increase in SBP, BMI, serum glucose and LDL-c.
Conclusions:
Even in a low-risk subsample, excluding individuals with hypertension, dyslipidemia or obesity, SBP, BMI and LDL-c were positively associated with higher maximal cIMT. This probably reflects a continuum of risk for atherosclerotic disease mediated by these measurements that do not evanesce with the exclusion of subjects who fulfill current diagnostic criteria for these conditions.