Associations of D-dimer and von Willebrand factor with atherosclerosis in Japanese and white men

Evaluation of Early Atherosclerosis Markers in Patients with Inflammatory Bowel Disease

BACKGROUND The aim of this study was to investigate relationships between early atherosclerosis and inflammatory bowel disease (IBD) using laboratory, functional, and morphological markers of atherosclerosis. MATERIAL AND METHODS In the present prospective single-center study, 96 patients with IBD (58 patients with ulcerative colitis and 36 patients with Crohn's disease) and 65 healthy control subjects were included. The demographic data of each patient and control subject were recorded. The patients with IBD and healthy controls were compared in terms of the carotid intima-media thickness (CIMT), the values of flow-mediated dilatation (FMD) and nitroglycerine-mediated dilatation (NMD), and the levels of von Willebrand factor antigen (VWF-Ag), D-dimer, and lipoprotein (a). RESULTS There were no significant differences between the IBD patients and controls in terms of age, sex, BMI, systolic and diastolic BPs, serum levels of total cholesterol, low-density lipoprotein, or triglycerides. IBD patients had significantly higher levels of VWF-Ag (156.6±58.9 vs. 104.2±43.3, P<0.001) and D-dimer (337.2±710.8 vs. 175.9±110.9, P<0.001) as compared to the controls. No significant differences were determined between the 2 groups in terms of FMD and NMD values. Although statistically not significant, the CIMT values were higher in the IBD patients than in the controls (0.517±0.141 mm vs. 0.467±0.099 mm, P=0.073). In the correlation analysis, the CIMT was found to be correlated negatively with FMD and positively with high sensitive C-reactive protein, VWF-Ag, and D-dimer. CONCLUSIONS These findings suggest that VWF-Ag and D-dimer can be beneficial early atherosclerosis markers in IBD patients.

Do differences in risk factors explain the lower rates of coronary heart disease in Japanese versus U.S. women?

BACKGROUND

Mortality from coronary heart disease (CHD) in women in Japan is one of the lowest in developed countries. In an attempt to shed some light on possible reasons of lower CHD in women in Japan compared with the United States, we extensively reviewed and analyzed existing national data and recent literature.

METHODS

We searched recent epidemiological studies that reported incidence of acute myocardial infarction (AMI) and examined risk factors for CHD in women in Japan. Then, we compared trends in risk factors between women currently aged 50-69 years in Japan and the United States, using national statistics and other available resources.

RESULTS

Recent epidemiological studies have clearly shown that AMI incidence in women in Japan is lower than that reported from other countries, and that lipids, blood pressure (BP), diabetes, smoking, and early menopause are independent risk factors. Comparing trends in risk factors between women in Japan and the United States, current levels of serum total cholesterol are higher in women in Japan and levels have been similar at least since 1990. Levels of BP have been higher in in Japan for the past 3 decades. Prevalence of type 2 diabetes has been similar in Japanese and white women currently aged 60-69 for the past 2 decades. In contrast, rates of cigarette smoking, although low in women in both countries, have been lower in women in Japan.

CONCLUSIONS

Differences in risk factors and their trends are unlikely to explain the difference in CHD rates in women in Japan and the United States. Determining the currently unknown factors responsible for low CHD mortality in women in Japan may lead to new strategy for CHD prevention.

Coronary artery calcification by computed tomography in epidemiologic research and cardiovascular disease prevention

Both American and European guidelines recommend coronary artery calcification (CAC) as a tool for screening asymptomatic individuals at intermediate risk for coronary heart disease (CHD). These recommendations are based on epidemiologic studies mostly in the United States. We review (1) the use of CAC in primary prevention of CHD in the United States, (2) epidemiologic studies of CAC in asymptomatic adults outside of the United States, and (3) international epidemiologic studies of CAC. This review will not consider clinical studies of CAC among patients or symptomatic individuals. US studies have shown that CAC is a strong independent predictor of CHD in both sexes among middle-aged and old age groups, various ethnic groups, and individuals with and without diabetes and that CAC plays an important role in reclassifying individuals from intermediate to high risk. Studies in Europe support these conclusions. The Electron-Beam Tomography, Risk Factor Assessment Among Japanese and US Men in the Post-World-War-II birth cohort (ERA JUMP) Study is the first international study to compare subclinical atherosclerosis, including CAC among Japanese, Japanese Americans, Koreans, and whites. It showed that as compared with whites, Japanese had lower levels of atherosclerosis, whereas Japanese Americans had similar or higher levels. CAC is being increasingly used as a screening tool for asymptomatic individuals in Europe and the United States. CAC is a powerful research tool, because it enables us to describe differences in atherosclerotic burden across populations. Such research could identify factors responsible for differences among populations, which may improve CHD prevention.