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Background: Lower ethnic-specific body mass index (BMI) cutpoints have been proposed for Asians and adapted in some countries. However, to our knowledge, no study has directly compared Asians to other ethnic groups to test differences in associations between BMI and all-cause mortality using common methods., Objectives: We estimated the association between BMI and all-cause mortality in Chinese Asians and Caucasian Americans to determine if lower Asian-specific BMI cutpoints are warranted., Methods: Extant data of the People's Republic of China Study (1983-1997) including 5546 Chinese and the Atherosclerosis Risk in Communities Study (1987-2002) including 9932 Caucasians aged 45-64 years at baseline were used. All analyses were performed using Cox proportional regression models., Results: Standardized mortality rates were 6.88 (95% confidence interval (CI): 5.75-8.24) and 5.50 (95% CI: 4.74-6.39) per 1000 person-years for Chinese and Caucasians, respectively. Standardized mortality probabilities by age 70 were similar across all BMI categories among Chinese. Furthermore, the probabilities were similar to those among Caucasians with BMI of 27.5-<32.5 kg/m2. The BMI associated with lowest mortality risk was almost identical between Chinese (25.1 kg/m2) and Caucasians (25.2 kg/m2). The analysis of categorical BMI did not reveal an increased mortality risk at any BMI category among Chinese. In contrast, compared to those with a BMI of 23.0-<25.0 kg/m2, risk was elevated by 35% among Caucasians with a BMI of 30.0-<32.5 kg/m2., Conclusions: These findings do not support different BMI cutpoints for Chinese than Caucasians on the basis of mortality rates.

The association of body mass index (BMI) with blood pressure may be stronger in Asian than non-Asian populations, however, longitudinal studies with direct comparisons between ethnicities are lacking. We compared the relationship of BMI with incident hypertension over approximately 9.5 years of follow-up in young (24-39 years) and middle-aged (45-64 years) Chinese Asians (n=5354), American Blacks (n=6076) and American Whites (n=13451). We estimated risk differences using logistic regression models and calculated adjusted incidences and incidence differences. To facilitate comparisons across ethnicities, standardized estimates were calculated using mean covariate values for age, sex, smoking, education and field center, and included the quadratic terms for BMI and age. Weighted least-squares regression models with were constructed to summarize ethnic-specific incidence differences across BMI. Wald statistics and p-values were calculated based on chi-square distributions. The association of BMI with the incidence difference for hypertension was steeper in Chinese (p<0.05) than in American populations during young and middle-adulthood. For example, at a BMI of 25 vs 21 kg/m2 the adjusted incidence differences per 1000 persons (95% CI) in young adults with a BMI of 25 vs those with a BMI of 21 was 83 (36- 130) for Chinese, 50 (26-74) for Blacks and 30 (12-48) for Whites; among middle-aged adults it was 137 (77-198) for Chinese, 49 (9-88) for Blacks and 54 (38-69) for Whites. Whether hypertension carries the same level of risk of stroke or cardiovascular disease across national or ethnic groups remains uncertain.

Age, family history, and body mass index (BMI) influence the prevalence of hypertension, but very little is known about the interplay of these factors in Chinese populations. The authors examined this issue in Chinese adults (n = 4104) in the People's Republic of China Study. In young adults (24-39 years), the prevalence of hypertension/1000 persons (95% confidence interval [CI]) at the referent BMI was greater among subjects with a parental history of hypertension (35; 15-54) compared with those without (7; 3-11). Among middle-aged (40-71 years) adults, the prevalence of hypertension was similar regardless of parental history; however, the effect of BMI was modified by parental history status. For example, at BMI = 25 kg/m(2), the prevalence difference/1000 persons was 375 (95% CI = 245-506) and 97 (95% CI = 51-144) among subjects with and without a parental history, respectively. These large differences call for further investigation of the genetic and environmental factors that could be driving this interaction.

Background: Several researchers have reported that Chinese adults may have a greater chronic disease burden than Whites, especially at lower body mass index (BMI) levels., Objectives: To compare the incidence of lipid abnormalities in Chinese (n=5303), White (n=10,752) and Black (n=3408) middle-aged adults and the effect of BMI on these incidences., Methods: Data were from the People's Republic of China (PRC) and the Atherosclerosis Risk in Communities (ARIC) studies. In each ethnic group, we calculated the adjusted cumulative incidence for high total cholesterol (≥240mg/dL), LDL-cholesterol (≥160mg/dL), and triglycerides (≥200mg/dL) and low HDL-cholesterol (≤40 in men and ≤50mg/dL in women) adjusted for age, gender, education, field site, smoking and drinking status. Risk differences associated with BMI (referent=18.5-22.9kg/m(2)) were calculated using weighted linear regression and slopes compared using the Wald test., Results: Chinese had lower incidence of abnormal total cholesterol, LDL-cholesterol and triglycerides than Whites in most BMI groups and had lower incidence of abnormal HDL-cholesterol and triglycerides than Blacks. Across the range of 18.5 to <30, BMI was more strongly associated with the incidence of having high total cholesterol in Chinese and Whites than in Blacks. Similar trends were seen for LDL-cholesterol and triglycerides, but were not always statistically significant. In contrast, BMI was more highly associated with incidence of low HDL-cholesterol in Whites than in Chinese or Blacks., Conclusion: Although differences in the incidence of lipid abnormalities and the impact of BMI were identified, results varied by lipid type indicating no consistent ethnic/national pattern., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Background: The associations between adiposity and metabolic risk factors have been suggested to vary across ethnicities. Studies in Caucasians have shown that after adjusting for waist circumference and body mass index (BMI), a larger hip circumference may be protective for metabolic risk factors. To our knowledge, these associations have never been examined in a Chinese population., Methods: Baseline (1987-1988) and follow-up (1993-1994) data were from the People's Republic of China Study (n = 1,144 men, n = 1,776 women). Logistic models were stratified by sex and adjusted for age, smoking, center, and education. Incidence differences (ID) comparing the sex specific 85(th) percentile to the 15(th) percentile of hip circumference were computed for elevated blood pressure, blood glucose and triglycerides, low high-density lipoprotein cholesterol (HDL-C), and multiple metabolic abnormalities (three or more of the aforementioned)., Results: In models adjusted for waist circumference and BMI, the ID [95% confidence interval (CI)] per 1,000 persons associated with a 12-cm larger hip were -132 (-237, -26) for low HDL-C; -85 (-138, -31) for elevated triglycerides; and -49 (-83, -4) for multiple metabolic abnormalities. In males, a larger hip circumference was not associated with a reduction of incident risk factors, although the ID tended to be negative., Conclusions: In Chinese women, greater mass in the lower trunk region was inversely associated with incident high triglycerides, low HDL-C, and multiple metabolic abnormalities when adjusted for general and central adiposity. This association was not detected in men. Additional research is needed to better understand the mechanisms by which fat at different depots results in differential risk.

Researchers have hypothesized that the impact of body mass index on chronic disease may be greater in Asians than in Whites; however, most studies are cross-sectional and have no White comparison group. The authors compared the associations with body mass index in Chinese Asians (n = 5,980), American Whites (n = 10,776), and American Blacks (n = 3,582) using prospective data from the People's Republic of China Study (1983-1994) and the Atherosclerosis Risk in Communities Study (1987-1998). Slopes of risk differences over body mass index levels were compared among the three ethnic groups in adjusted analyses. The authors found larger associations with body mass index in Chinese Asians compared with American Whites and Blacks for hypertension (p < 0.05). The increase in the incidence of hypertension associated with a one-unit increase in body mass index over approximately 8 years of follow-up was 2.5, 1.7, and 1.8 percentage points for Chinese Asians, American Whites, and American Blacks, respectively. For diabetes, the estimates were 1.7, 1.1, and 1.6 percentage points for the same groups- higher in Chinese Asians than in American Whites (p < 0.05) but similar between Chinese Asians and American Blacks. Given the ethnic differences in associations, the results support advocacy of public health and medical actions toward obesity prevention and treatment in China.