Byambaa Enkhmaa

The New BMI Criteria for Asians by the Regional Office for the Western Pacific Region of WHO are Suitable for Screening of Overweight to Prevent Metabolic Syndrome in Elder Japanese Workers

The New BMI Criteria for Asians by the Regional Office for the Western Pacific Region of WHO are Suitable for Screening of Overweight to Prevent Metabolic Syndrome in Elder Japanese Workers: Erdembileg Anuurad, et al. Department of Environmental and Preventive Medicine, Shimane University School of Medicine—Obesity occurs less frequently in Japanese than in various other ethnic populations. A person with abnormal glucose tolerance is often found to have one or more of the other cardiovascular disease risk factors, such as obesity, hypertension and hyperlipidemia. This clustering has been labeled as metabolic syndrome (WHO, 1998). It was suggested that Japanese, categorized as having normal weight (BMI of less than 25.0), as defined by the WHO (2000), have an increasing tendency toward metabolic syndrome. Our objective was to analyze metabolic syndrome in “Overweight” with BMI of 23.0–24.9 in Japanese workers, and to assess the suitability for Asians of the Regional Office for the Western Pacific Region of WHO criteria pertaining to obesity (WPRO criteria, 2000). We conducted a cross‐sectional study in the workplace setting and investigated the relationship between BMI classification based on WPRO criteria and metabolic syndrome by gender and age group (18–44 yr vs. 45–60 yr). Three hundred seventy‐nine men and 432 women Japanese workers participated in this study. BMI were categorized as 20% “Overweight” (23.0–24.9 BMI), 20% “Obese I” (25.0–29.9 BMI) and 2% “Obese II” (over 30.0 BMI), based on WPRO criteria. Graded increases in BMI were positively associated with body fat percentage, waist circumference, hip circumference and waist/hip ratio in both genders and age groups. A progressively increasing BMI category in the elder group aged 45– 60 yr in both genders was positively related with parameters constituting metabolic syndrome. Graded increases in BMI classes in elder workers based on WPRO criteria were positively associated with prevalence of metabolic syndrome, and “Overweight” elder women had significantly higher prevalence of metabolic syndrome. The present investigation, based on the increasing risks of “Overweight” with a BMI of 23.0–24.9, suggests that WPRO criteria are suitable for Japanese workers aged over 45 yr.

Overweight Japanese with body mass indexes of 23.0-24.9 have higher risks for obesity-associated disorders: a comparison of Japanese and Mongolians.

OBJECTIVE: The degree of obesity of Asians is less than that of Caucasians. It has been suggested that Japanese, categorized as having normal weight (BMI<25.0), as defined by WHO (2000), have a tendency toward increased incidences of dyslipidemia and diabetes. Our objective was to analyze parameters constituting obesity-associated disorders in overweight Japanese and Mongolians with a body mass index (BMI) of 23.0–24.9, and to assess the suitability for Asians of the Regional Office for Western Pacific Region of WHO criteria pertaining to obesity (WPRO criteria, 2000).DESIGN: Cross-sectional study in a workplace setting.SUBJECTS: A total of 386 Japanese men and 363 Japanese women, and 102 Mongolian men and 155 Mongolian women.MEASUREMENTS: Anthropometric measurements (weight, height, waist circumference, hip circumference and blood pressure) and metabolic measurements (plasma levels of total cholesterol, HDL cholesterol, triglyceride, glucose and insulin).RESULTS: Graded increases in BMI of Japanese and Mongolians were positively associated with body fat percent, waist circumference, hip circumference and waist/hip ratio. The Japanese were categorized as 22% overweight, 22% obese I, 3% obese II; the Mongolians rated as 18% overweight, 34% obese I, 19% obese II, based on the WPRO BMI criteria. The Mongolians had a higher prevalence of obesity and a higher body fat percent, but a lesser gradation of dyslipidemia, than did the BMI-matched Japanese groups. Overweight Japanese (BMI 23.0–24.9), in comparison to normal Japanese (BMI 18.5–22.9), had significant differences in systolic blood pressure, HDL-choresterol and triglyceride in men, and in systolic and diastolic blood pressure, HDL-choresterol, triglyceride, insulin and Homoeostasis model assessment-insulin resistance in women. In contrast, the Mongolians showed no significant differences in metabolic parameters between overweight and normal subjects, except for diastolic blood pressure.CONCLUSION: Since the relationship between abdominal fat mass and BMI is ethnic-specific, a universal BMI cutoff point is inappropriate for Asian populations such as the Japanese and Mongolians. The present investigation suggests that, while the WPRO criteria are suitable for Japanese, the WHO criteria are more appropriate for Mongolians.

Prevalence of the metabolic syndrome using the modified ATP III definitions for workers in Japan, Korea and Mongolia.

Prevalence of the Metabolic Syndrome using the Modified ATP III Definitions for Workers in Japan, Korea and Mongolia: Kuninori Shiwaku, et al. Department of Environmental and Preventive Medicine, Shimane University School of Medicine— A clustering of insulin resistance, hypertension and dyslipidemia has been labeled as the metabolic syndrome. Asians have a lower frequency of obesity than do Caucasians, but have an increasing tendency toward metabolic syndrome. Most data on metabolic syndrome are based on studies from Western countries with only limited information derived from Asian populations. We conducted a cross‐sectional study of individuals aged 30–60 yr in workplace settings. We examined and analyzed the health data of 1,384 Japanese, Koreans and Mongolians for metabolic syndrome based on the modified definitions of the working definition proposed by the Third Report of the National Cholesterol Educational Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (ATP III definition). The prevalence of metabolic syndrome using the ATP III‐BMI30 and ATP III‐BMI25 definitions was 7% and 12% for Japanese, 7% and 13% for Koreans, and 12% and 16% for Mongolians, respectively. With the exception of obesity, the prevalences of individual metabolic abnormalities within each of the three Asian groups were similar to each other and to reported rates of prevalence in the U.S.A. Nevertheless, the values of sensitivity and specificity by the metabolic syndrome definitions are remarkably different relative to ethnicity. A universal metabolic syndrome definition is inappropriate for comparisons of metabolic syndrome among Asian ethnic groups. We believe that the ATP III‐BMI25 definition is suitable for the determination of metabolic syndrome among Japanese and Koreans, and that the ATP III‐BMI30 is more appropriate for Mongolians.

Difficulty in losing weight by behavioral intervention for women with Trp64Arg polymorphism of the β3-adrenergic receptor gene

OBJECTIVE: Trp64Arg mutation in the β 3-adrenergic receptor (β 3AR) gene is relatively common in Japanese people. However, it has not been clear whether persons with Trp64Arg mutation in the β 3AR gene tend to have obesity and difficulty in losing weight even with a restricted diet and exercise. We investigated the response of body weight and metabolic factors to behavioral intervention in Japanese women with Trp64Arg mutation in the β 3AR gene.DESIGN: A 3-month behavioral intervention study using a combination of diet and exercise programs.SUBJECTS: A total of 76 perimenopausal women with no clinical symptoms (age: 54.7±7.7 y, body mass index (BMI): 21.0–33.0 kg/m2).MEASUREMENTS: Anthropometric measurements (weight, height, body fat, waist circumference, hip circumference, skin fold, resting energy expenditure and blood pressure) and metabolic measurements (serum levels of cholesterol, triglyceride, phospholipid, nonesterified fatty acid, glucose, insulin and leptin) and determination of the β 3AR genotype by polymerase chain reaction followed by BstNI digestion.RESULTS: At the baseline of BMI, body weight, body fat, waist circumference, hip circumference, the arm skin fold, resting energy expenditure, or blood lipid and glucose profiles, there was no significant difference in participants with/without mutation of the β 3AR gene. The intervention yielded a body weight reduction in 69 and 48%, and induced a significant difference in weight loss (−0.74 and −0.01 kg) for women with wild-type and Trp64Arg mutation, respectively. Significant differences of anthropometric parameters were found in body weight, BMI, waist and hip circumferences and blood pressure of wild type by the intervention. However, women with Trp64Arg mutation did not show significant changes in these anthropometric parameters, except for hip circumference. A significant difference was found in high-density lipoprotein cholesterol (HDL-C) and in the low-density lipoprotein cholesterol/HDL-C ratio in both genotypes.CONCLUSION: The results of the present study suggest that the Trp64Arg mutation of the β 3AR gene is associated with difficulty in losing weight through behavioral intervention, although it is not related to obesity-related phenotypes and resting energy expenditure before the intervention.

Lipoprotein(a): Genotype–Phenotype Relationship and Impact on Atherogenic Risk

In 2010, more than 45 years after the initial discovery of lipoprotein(a) [Lp(a)] by Kare Berg, an European Atherosclerosis Society Consensus Panel recommended screening for elevated Lp(a) in people at moderate to high risk of atherosclerotic cardiovascular disease (CVD). This recommendation was based on extensive epidemiological findings demonstrating a significant association between elevated plasma Lp(a) levels and coronary heart disease, myocardial infarction, and stroke. In addition to those patients considered to be at moderate to high risk of heart disease, statin-treated patients with recurrent heart disease were also identified as targeted for screening of elevated Lp(a) levels. Taken together, recent findings have significantly strengthened the notion of Lp(a) as a causal risk factor for CVD. It is well established that Lp(a) levels are largely determined by the size of the apolipoprotein a [apo(a)] gene; however, recent studies have identified several other LPA gene polymorphisms that have significant associations with an elevated Lp(a) level and a reduced copy number of K4 repeats. In addition, the contribution of other genes in regulating Lp(a) levels has been described. Besides the strong genetic regulation, new evidence has emerged regarding the impact of inflammation as a modulator of Lp(a) risk factor properties. Thus, oxidized phospholipids that possess a strong proinflammatory potential are preferentially carried on Lp(a) particles. Collectively, these findings point to the importance of both phenotypic and genotypic factors in influencing apo(a) proatherogenic properties. Therefore, studies taking both of these factors into account determining the amount of Lp(a) associated with each individual apo(a) size allele are valuable tools when assessing a risk factor role of Lp(a).

Lipoprotein (a): impact by ethnicity and environmental and medical conditions

Levels of lipoprotein (a) [Lp(a)], a complex between an LDL-like lipid moiety containing one copy of apoB, and apo(a), a plasminogen-derived carbohydrate-rich hydrophilic protein, are primarily genetically regulated. Although stable intra-individually, Lp(a) levels have a skewed distribution inter-individually and are strongly impacted by a size polymorphism of the LPA gene, resulting in a variable number of kringle IV (KIV) units, a key motif of apo(a). The variation in KIV units is a strong predictor of plasma Lp(a) levels resulting in stable plasma levels across the lifespan. Studies have demonstrated pronounced differences across ethnicities with regard to Lp(a) levels and some of this difference, but not all of it, can be explained by genetic variations across ethnic groups. Increasing evidence suggests that age, sex, and hormonal impact may have a modest modulatory influence on Lp(a) levels. Among clinical conditions, Lp(a) levels are reported to be affected by kidney and liver diseases.

Association of Lipoprotein-Associated Phospholipase A2 with Coronary Artery Disease in African-Americans and Caucasians

CONTEXT Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is bound predominately to low-density lipoprotein and has been implicated as a risk factor for coronary artery disease (CAD). OBJECTIVE We investigated the association between Lp-PLA(2) and CAD in a biethnic African-American and Caucasian population. DESIGN Lp-PLA(2) mass, activity, and index, an integrated measure of mass and activity, and other cardiovascular risk factors were determined in 224 African-Americans and 336 Caucasians undergoing coronary angiography. MAIN OUTCOME MEASURES We assessed the distribution of Lp-PLA(2) levels and determined the predictive role of Lp-PLA(2) as a risk factor for CAD. RESULTS Levels of Lp-PLA(2) mass and activity were higher among Caucasians compared with African-Americans (293 +/- 75 vs. 232 +/- 76 ng/ml, P < 0.001 for mass and 173 +/- 41 vs. 141 +/- 39 nmol/min/ml, P < 0.001 for activity, respectively). However, Lp-PLA(2) index was similar in the two groups (0.61 +/- 0.17 vs. 0.64 +/- 0.19, P = NS). In both ethnic groups, Lp-PLA(2) activity and index was significantly higher among subjects with CAD. African-American subjects with CAD had significantly higher Lp-PLA(2) index than corresponding Caucasian subjects (0.69 +/- 0.20 vs. 0.63 +/- 0.18, P = 0.028). In multivariate regression analyses, after adjusting for other risk factors, Lp-PLA(2) index was independently (odds ratio 6.7, P = 0.047) associated with CAD in African-Americans but not Caucasians. CONCLUSIONS Lp-PLA(2) activity and index was associated with presence of CAD among African-Americans and Caucasians undergoing coronary angiography. The findings suggest an independent impact of vascular inflammation among African-Americans as contributory to CAD risk and underscore the importance of Lp-PLA(2) as a cardiovascular risk factor.

Postprandial Lipoproteins and Cardiovascular Disease Risk in Diabetes Mellitus

Diabetes mellitus is associated with increased risk for atherosclerotic cardiovascular disease (CVD). Recent prospective studies in healthy individuals suggest that the postprandial triglyceride (TG) level is a better independent predictor for assessing future CVD events than fasting TG levels. In contrast, results have been more controversial among diabetic patients, as some studies report a positive association between postprandial TG and CVD. This raises the issue of to what extent postprandial TG levels may be of predictive value in the diabetic population. One possibility impacting on the predictive power of postprandial TG in identifying CVD risk may be the presence of other risk factors, including alterations in lipid and lipoprotein metabolism, which could make it more difficult to identify the impact of postprandial lipemia on cardiovascular risk. The findings provide a challenge to develop a better approach to assess the impact of postprandial lipemia on CVD risk under diabetic conditions.

Apo E4 and lipoprotein-associated phospholipase A2 synergistically increase cardiovascular risk

OBJECTIVE Apolipoprotein E (apoE) has been implicated as conveying increased risk for coronary artery disease (CAD). Previous studies suggest a role of apoE as a modulator of immune response and inflammatory properties. We hypothesized that the presence of apo E4 is associated with an increased inflammatory burden in subjects with CAD as compared to subjects without CAD. METHODS ApoE genotypes, systemic (C-reactive protein [CRP], fibrinogen, serum amyloid-A [SAA]) and vascular inflammatory markers (Lipoprotein-associated phospholipase A(2) [Lp-PLA(2)] and pentraxin-3 [PTX-3]) were assessed in 324 Caucasians and 208 African Americans, undergoing coronary angiography. RESULTS For both ethnic groups, Lp-PLA(2) index, an integrated measure of Lp-PLA(2) mass and activity, increased significantly and stepwise across apoE isoforms (P = 0.009 and P = 0.026 for African Americans and Caucasians respectively). No differences were found for other inflammatory markers tested (CRP, fibrinogen, SAA and PTX-3). For the top cardiovascular score tertile, apo E4 carriers had a significantly higher level of Lp-PLA(2) index in both ethnic groups (P = 0.027 and P = 0.010, respectively). CONCLUSION The presence of the apo E4 isoform was associated with a higher level of Lp-PLA(2) index, a marker of vascular inflammation. Our results suggest that genetic variation at the apoE locus may impact cardiovascular disease risk through enhanced vascular inflammation.

Age as a Modulator of Inflammatory Cardiovascular Risk Factors

Objective— Levels of acute phase reactants are affected by age. The extent to which cardiovascular risk associated with aging is due to an increase in the inflammatory burden is not known. We assessed the relationship with age of inflammatory markers, representing (1) systemic (C-reactive protein, fibrinogen, and serum amyloid-A) and (2) vascular (lipoprotein-associated phospholipase A2 and pentraxin-3) inflammation. Methods and Results— We determined lipoprotein-associated phospholipase A2 mass and activity, C-reactive protein, fibrinogen, serum amyloid-A, and pentraxin-3 levels and other cardiovascular disease risk factors in 336 whites and 224 African Americans. Levels of systemic inflammatory markers increased significantly with age in both ethnic groups (P<0.05 for all), whereas trend patterns of vascular inflammatory markers did not change significantly with age for either group. In multivariate regression models adjusting for confounding variables, age remained independently associated with a composite Z score for systemic but not vascular inflammation (&bgr;=0.250, P<0.001, and &bgr;=0.276, P<0.001, for whites and African Americans, respectively). Conclusion— We report an increase in the systemic but not vascular inflammatory burden with age. Levels of both categories of inflammatory markers with age were similar across ethnicity after adjustment for confounders. Our results underscore the importance of age in evaluating inflammatory markers to assess cardiovascular risk.