BACKGROUND: Carotid intima-media thickness (CIMT) measurements have been widely used as primary endpoint in studies into the effects of new interventions as alternative for cardiovascular morbidity and mortality. There are no accepted standards on the use of CIMT measurements in intervention studies and choices in the design and analysis of a CIMT study are generally based on experience and expert opinion. In the present review, we provide an overview of the current evidence on several aspects in the design and analysis of a CIMT study on the early effects of new interventions. SUMMARY OF ISSUES: A balanced evaluation of the carotid segments, carotid walls, and image view to be used as CIMT study endpoint; the reading method (manual or semi-automated and continuously or in batch) to be employed, the required sample size, and the frequency of ultrasound examinations is provided. We also discuss the preferred methods to analyse longitudinal CIMT data and address the possible impact of, and methods to deal with missing and biologically implausible CIMT values. CONCLUSIONS: Linear mixed effects models are the preferred way to analyse CIMT data and do appropriately handle missing and biologically implausible CIMT values. Furthermore, we recommend to use extensive CIMT designs that measure CIMT at regular points during the multiple carotid sites as such approach is likely to increase the success rates of CIMT intervention studies designed to evaluate the effects of new interventions on atherosclerotic burden.
Atherosclerosis ; Carotid Intima-Media Thickness ; Expert Testimony ; Clinical Trial ; Sample Size ; Statistics as Topic

Advances in the field of carotid ultrasound have been incremental, resulting in a steady decrease in measurement variability. Improvements in edge detection algorithms point toward increasing automation of CIMT measurements. The major advantage of CIMT is that it is completely noninvasive and can be repeated as often as required. It provides a continuous measure since all subjects have a measurable carotid wall. It is also relatively inexpensive to perform, and the technology is widely available. A graded relation between raising LDL cholesterol and increased CIMT is apparent. Increased CIMT has been shown consistently to relate the atherosclerotic abnormalities elsewhere in the arterial system. Moreover, increased CIMT predicts future vascular events in both populations from Caucasian ancestry and those from Asian ancestry. Furthermore, lipid‑lowering therapy has been shown to affect CIMT progression within 12–18 months in properly designed trials with results congruent with clinical events trials. In conclusion, when one wants to evaluate the effect of a pharmaceutical intervention that is to be expected to beneficially affect atherosclerosis progression and to reduce CV event risk, the use of CIMT measurements over time is a valid, suitable, and evidence‑based choice.
Atherosclerosis ; diagnosis ; Cardiovascular Diseases ; diagnosis ; Carotid Intima-Media Thickness ; Humans ; Randomized Controlled Trials as Topic

BACKGROUNDThe metabolic syndrome is a clustering of metabolic abnormalities and has been associated with increased risk of type 2 diabetes mellitus and cardiovascular disease. This study aimed to estimate the prevalence of the metabolic syndrome among employees in Northeast China.

METHODSTotally, 33,149 employees who received health screening in the International Health Promotion Center in the First Hospital of Jilin University were enrolled. Height, weight, waist circumference, blood pressure, fasting plasma glucose, triglyceride, high-density lipoprotein, and low-density lipoprotein were recorded. Three definitions for the metabolic syndrome were applied, revised National Cholesterol Education Program's Adult Treatment Panel III (NCEP ATP III) criteria, the International Diabetes Federation (IDF) criteria, and the Chinese Diabetes Society (CDS) criteria.

RESULTSOverall, the age-standardized prevalence of the metabolic syndrome was 22.9%, 20.6%, and 15.3% based on definitions of revised NCEP ATP III criteria, the IDF criteria, and the CDS criteria, respectively. Men had higher age-standardized prevalence than women in all three definitions (P < 0.05). The prevalence was 27.1%, 24.5%, and 20.4% for men; 17.1%, 15.4%, and 8.3% for women, respectively. The most common metabolic component with the metabolic syndrome was overweight (54.7% of men had an elevated body mass index, and 35.9% of women had central obesity).

CONCLUSIONSA large proportion of employees among Northeast China have the metabolic syndrome. These findings place emphasis on the need to develop aggressive lifestyle modification for patients with the metabolic syndrome and population level strategies for the prevention, detection, and treatment of cardiovascular risk.

Blood Pressure ; physiology ; China ; epidemiology ; Female ; Humans ; Male ; Metabolic Syndrome ; epidemiology ; Obesity ; epidemiology ; Overweight ; epidemiology