Baseline Intima-media Thickness Research Articles

Effects of Dietary and Exercise Intervention on Progression of Carotid Intima-Media Thickness

P96 The Women’s Healthy Lifestyle clinical trial has reported that a dietary and exercise intervention results in the prevention of weight gain and LDL cholesterol rise over a 54 month follow-up in pre-menopausal women approaching menopause (average age 47 at baseline and 52 at final follow-up). During this trial, serial carotid ultrasound was performed in 234 women with an average of 3.5 years between scans. Intima-Media Thickness (IMT) was the mean of measures taken in the right and left common, bulb and internal carotid arteries. The average change in carotid IMT over time was +0.033 mm. Change in IMT was higher among the control than the intervention group (.039 mm vs. .027 mm, p = .172). Among 109 women who had reached menopause by the end of the study, average IMT progression was .058 mm among controls vs. .017 mm among the intervention group (p=.003, a difference of .041 mm). Among HRT users, IMT progression was .037 mm greater among control vs intervention women (N= 60, p = .040) and this difference was .047 mm among HRT non-users (N= 46, p=.035). Linear regression was used to determine whether the treatment effect was independent of minor differences between treatment groups at baseline and changes in vessel diameter over follow-up. After controlling for age, baseline IMT, baseline adventitial diameter, change in adventitial diameter, hysterectomy status, smoking, baseline waist girth and baseline energy expenditure, the treatment effect remained significant (p=.005). Among these postmenopausal women, the control group had greater increases in weight, waist circumference and LDL, and a lower increase in Kilocalories of energy expenditure over follow-up in comparison to the intervention group (p < .01 for all but LDL). When change in each risk factor was tested in the model above, only change in waist girth modified the treatment effect. Increase in waist girth was positively associated with IMT progression (p=.04) and the p-value associated with the treatment effect was reduced from .005 to .04. We conclude that among women entering menopause, a successful dietary and exercise intervention was associated with measurable slowing of atherosclerosis progression.

Effect of aggressive versus conventional lipid lowering on atherosclerosis progression in familial hypercholesterolemia (ASAP): a prospective, randomised, double-blind trial

High LDL-cholesterol is a risk factor for atherosclerosis. We aimed to determine whether aggressive cholesterol lowering with statins was more effective than conventional statin treatment in this disease. We investigated the effect of high-dose atorvastatin on carotid atherosclerosis progression. We did a randomised, double-blind clinical trial in 325 patients with familial hypercholesterolaemia. Patients were given either atorvastatin 80 mg (n=160) or simvastatin 40 mg (n=165) daily, on an intent-to-treat basis. The primary endpoint was the change of carotid intima media thickness (IMT), as measured by quantitative B-mode ultrasound, over 2 years. The overall baseline IMT, combining the measurements of the common and internal carotid artery and the carotid bifurcation on both sides, was 0.93 mm (SD 0.22) and 0.92 mm (0.21) in the atorvastatin and simvastatin groups, respectively. After treatment with atorvastatin for 2 years, IMT decreased (-0.031 mm [95% CI -0.007 to -0.055]; p=0.0017), whereas in the simvastatin group it increased (0.036 [0.014-0.058]; p=0.0005). The change in thickness differed significantly between the two groups (p=0.0001). Atorvastatin showed greater reductions in cholesterol concentrations than did simvastatin. HDL-cholesterol concentrations increased in both groups. Both drugs were equally well tolerated. Our results show that aggressive LDL-cholesterol reduction by atorvastatin was accompanied by regression of carotid intima media thickness in patients with familial hypercholesterolaemia, whereas conventional LDL lowering was not.

Socioeconomic status and progression of carotid atherosclerosis. Prospective evidence from the Kuopio Ischemic Heart Disease Risk Factor Study.

Socioeconomic status (SES) is importantly associated with cardiovascular morbidity and mortality, but no information exists on the relationship between SES and progression of atherosclerotic vascular disease. We investigated the association between education and income and the 4-year progression of carotid atherosclerosis in a population-based sample of Finnish men. Data from the Kuopio Ischemic Heart Disease Risk Factor Study were used to estimate changes in maximum and mean intima-media thickness (IMT) and maximum plaque height across levels of SES in 1022 men. Associations between SES and atherosclerotic progression were examined in relation to risk factors and stratified by baseline levels of atherosclerosis and prevalent ischemic heart disease (IHD). There were significant, inverse, graded relationships between levels of education and income for all three progression measures, which were largely unaffected by risk factor adjustment. For education, the age- and baseline IMT-adjusted maximum progression for those with primary schooling or less was 0.28 mm and for those who graduated from high school, 0.24 mm (P = .05). Compared with the lowest SES group, men with the highest SES had 14% to 29% less atherosclerotic progression, depending on the measure used. Associations of the same magnitude were evident in subgroups without advanced baseline IMT and in men who were free of IHD. These results show that men with poor education and low income have significantly greater progression of carotid atherosclerosis than men with more advantages. The findings strengthen the contention that SES plays a significant role early in the atherosclerotic disease process and that reducing the burden of atherosclerotic vascular disease associated with lower SES will require approaches that focus on all stages of the life course.

Kuopio Atherosclerosis Prevention Study (KAPS)

The atherosclerotic progression-reducing effect of LDL cholesterol (LDL-C) lowering has been established in subjects with severe atherosclerotic disease but not in persons with elevated LDL cholesterols without severe atherosclerosis. KAPS (Kuopio Atherosclerosis Prevention Study) is the first population-based trial in the primary prevention of carotid and femoral atherosclerosis. The eligibility requirements were serum LDL-C > or = 4.0 mmol/L and total cholesterol < 7.5 mmol/L. Out of a geographically defined population, 447 men aged 44 to 65 years (mean, 57) were randomized to pravastatin (40 mg/d) or placebo for 3 years. Less than 10% of the subjects had prior myocardial infarction. Thirty-nine men discontinued study medication; however, efficacy data were available for 424 men. The primary outcome was the rate of carotid atherosclerotic progression, measured as the linear slope over annual ultrasound examinations in the average of the maximum carotid intima-media thickness (IMT) of the far wall of up to four arterial segments (the right and left distal common carotid artery and the right and left carotid bulb). For the carotid arteries, at the overall mean baseline IMT of 1.66 mm, the rate of progression of carotid atherosclerosis was 45% (95% CI, 16 to 69%) less in the pravastatin (0.017 mm/y) than the placebo (0.031 mm/y) group (P = .005). In the common carotid artery there was a treatment effect of 66% (95% CI, 30 to 95%; pravastatin 0.010 mm/y; placebo 0.029 mm/y; P < .002) at the overall mean baseline IMT of 1.35 mm. A treatment effect of 30% (95% CI, -1% to 54%) was found for the carotid bulb (pravastatin, 0.028; placebo, 0.040; P = .056) at the overall mean baseline IMT of 2.0 mm. The treatment effect was larger in subjects with higher baseline IMT values, in smokers and in those with low plasma vitamin E levels. There was no significant treatment effect on atherosclerotic progression in the femoral arteries. These data establish the antiatherogenic effect of LDL-C lowering by pravastatin in hypercholesterolemic men in a primary prevention setting and suggest a greater effect in smokers than in nonsmokers.