Dongfeng Gu

Prevalence of the metabolic syndrome and overweight among adults in China.

BACKGROUND The metabolic syndrome and obesity are major risk factors for cardiovascular disease. Little information exists on the prevalence of the metabolic syndrome in China. We aimed to provide up-to-date estimates of the prevalence of the metabolic syndrome and overweight in the general adult population in China. METHODS We did a cross-sectional survey in a nationally representative sample of 15,540 Chinese adults aged 35-74 years in 2000-01. Metabolic syndrome was defined according to guidelines from the US National Cholesterol Education Program. Overweight was defined as body-mass index of 25.0 kg/m2 or greater. FINDINGS The age-standardised prevalence of metabolic syndrome was 9.8% (95% CI 9.0-10.6) in men and 17.8% (16.6-19.0) in women. The age-standardised prevalence of overweight was 26.9% (25.7-28.1) in men and 31.1% (29.7-32.5) in women. The prevalence of the metabolic syndrome and overweight was higher in northern than in southern China, and higher in urban than rural residents. INTERPRETATION Our results indicate that a large proportion of Chinese adults have the metabolic syndrome and that overweight has become an important public health problem in China. These findings emphasise the urgent need to develop national strategies for the prevention, detection, and treatment of overweight and the metabolic syndrome, to reduce the societal burden of cardiovascular disease in China.

Association between Body-Mass Index and Risk of Death in More Than 1 Million Asians

BACKGROUND Most studies that have evaluated the association between the body-mass index (BMI) and the risks of death from any cause and from specific causes have been conducted in populations of European origin. METHODS We performed pooled analyses to evaluate the association between BMI and the risk of death among more than 1.1 million persons recruited in 19 cohorts in Asia. The analyses included approximately 120,700 deaths that occurred during a mean follow-up period of 9.2 years. Cox regression models were used to adjust for confounding factors. RESULTS In the cohorts of East Asians, including Chinese, Japanese, and Koreans, the lowest risk of death was seen among persons with a BMI (the weight in kilograms divided by the square of the height in meters) in the range of 22.6 to 27.5. The risk was elevated among persons with BMI levels either higher or lower than that range--by a factor of up to 1.5 among those with a BMI of more than 35.0 and by a factor of 2.8 among those with a BMI of 15.0 or less. A similar U-shaped association was seen between BMI and the risks of death from cancer, from cardiovascular diseases, and from other causes. In the cohorts comprising Indians and Bangladeshis, the risks of death from any cause and from causes other than cancer or cardiovascular disease were increased among persons with a BMI of 20.0 or less, as compared with those with a BMI of 22.6 to 25.0, whereas there was no excess risk of either death from any cause or cause-specific death associated with a high BMI. CONCLUSIONS Underweight was associated with a substantially increased risk of death in all Asian populations. The excess risk of death associated with a high BMI, however, was seen among East Asians but not among Indians and Bangladeshis.

Future Cardiovascular Disease in China Markov Model and Risk Factor Scenario Projections From the Coronary Heart Disease Policy Model–China

Background—The relative effects of individual and combined risk factor trends on future cardiovascular disease in China have not been quantified in detail. Methods and Results—Future risk factor trends in China were projected based on prior trends. Cardiovascular disease (coronary heart disease and stroke) in adults ages 35 to 84 years was projected from 2010 to 2030 using the Coronary Heart Disease Policy Model–China, a Markov computer simulation model. With risk factor levels held constant, projected annual cardiovascular events increased by >50% between 2010 and 2030 based on population aging and growth alone. Projected trends in blood pressure, total cholesterol, diabetes (increases), and active smoking (decline) would increase annual cardiovascular disease events by an additional 23%, an increase of approximately 21.3 million cardiovascular events and 7.7 million cardiovascular deaths over 2010 to 2030. Aggressively reducing active smoking in Chinese men to 20% prevalence in 2020 and 10% prevalence in 2030 or reducing mean systolic blood pressure by 3.8 mm Hg in men and women would counteract adverse trends in other risk factors by preventing cardiovascular events and 2.9 to 5.7 million total deaths over 2 decades. Conclusions—Aging and population growth will increase cardiovascular disease by more than a half over the coming 20 years, and projected unfavorable trends in blood pressure, total cholesterol, diabetes, and body mass index may accelerate the epidemic. National policy aimed at controlling blood pressure, smoking, and other risk factors would counteract the expected future cardiovascular disease epidemic in China.

Metabolic syndrome and salt sensitivity of blood pressure in non-diabetic people in China: a dietary intervention study.

BACKGROUND Since insulin resistance is thought to be the underlying mechanism for metabolic syndrome, affected individuals might be sensitive to a dietary sodium intervention. We aimed to examine the association between metabolic syndrome and salt sensitivity of blood pressure. METHODS 1906 Chinese participants without diabetes, aged 16 years or more, were selected to receive a low-sodium diet (51.3 mmol per day) for 7 days followed by a high-sodium diet (307.8 mmol per day) for an additional 7 days. Participants were excluded from the analysis if metabolic risk factor information was missing or if they did not complete their dietary interventions. Blood pressure was measured at baseline and on days 2, 5, 6, and 7 of each intervention. Metabolic syndrome was defined as the presence of three or more of: abdominal obesity, raised blood pressure, high triglyceride concentration, low HDL cholesterol, or high glucose. High salt sensitivity was defined as a decrease in mean arterial blood pressure of more than 5 mm Hg during low-sodium or an increase of more than 5 mm Hg during high-sodium intervention. This study is registered with ClinicalTrials.gov, number NCT00721721. FINDINGS Of the 1881 participants with information regarding metabolic syndrome, 283 had metabolic syndrome. 1853 participants completed the low-sodium diet and 1845 completed the high-sodium diet. Multivariable-adjusted mean changes in blood pressure were significantly greater in participants with metabolic syndrome than in those without on both low-sodium and high-sodium diets (p<0.0001 for all comparisons). Additionally, risk of salt sensitivity rose with increasing numbers of risk factors for metabolic syndrome. Compared with those with no risk factors, participants with four or five had a 3.54-fold increased odds (95% CI 2.05-6.11) of high salt-sensitivity during the low-sodium and a 3.13-fold increased odds (1.80-5.43) of high salt-sensitivity during the high-sodium intervention. INTERPRETATION These results suggest that metabolic syndrome enhances blood pressure response to sodium intake. Reduction in sodium intake could be an especially important component in reducing blood pressure in patients with multiple risk factors for metabolic syndrome.

Prevalence of Cardiovascular Disease Risk Factor Clustering Among the Adult Population of China Results From the International Collaborative Study of Cardiovascular Disease in Asia (InterAsia)

Background—The prevalence of cardiovascular disease (CVD) risk factors has been increasing in China. Methods and Results—We examined the prevalence of CVD risk factor clustering among Chinese adults aged 35 to 74 years with data from the International Collaborative Study of Cardiovascular Disease in Asia (InterAsia), a cross-sectional survey of a nationally representative sample (n=14 690) conducted during 2000 to 2001 and compared these data with those of US adults from the National Health and Nutrition Examination Survey of 1999 to 2000. Overall, 80.5%, 45.9%, and 17.2% of Chinese adults had ≥1, ≥2, and ≥3 modifiable CVD risk factors (dyslipidemia, hypertension, diabetes, cigarette smoking, and overweight), respectively. By comparison, 93.1%, 73.0%, and 35.9% of US adults had ≥1, ≥2, and ≥3 of these risk factors, respectively. In a multivariate model including age, sex, and area of residence, the odds ratio (95% confidence interval [CI]) of having ≥1, ≥2, and ≥3 CVD risk factors versus none of the studied risk factors was 2.61 (95% CI, 2.09 to 3.27), 3.55 (95% CI, 2.77 to 4.54), and 4.97 (95% CI, 3.67 to 6.74), respectively, for Chinese adults 65 to 74 years old versus 35 to 44 years old; 3.65 (95% CI, 3.21 to 4.15), 4.67 (95% CI, 4.06 to 5.38), and 5.60 (95% CI, 4.70 to 6.67), respectively, for men compared with women; 1.18 (95% CI, 1.07 to 1.30), 1.34 (95% CI, 1.21 to 1.50), and 1.84 (95% CI, 1.60 to 2.12), respectively, for urban compared with rural residents; and 1.98 (95% CI, 1.76 to 2.22), 2.75 (95% CI, 2.42 to 3.13), and 4.36 (95% CI, 3.68 to 5.18), respectively, for residents of northern compared with southern China. Conclusions—Clustering of CVD risk factors is common in China. Prevention, detection, and treatment of CVD risk factor clustering should be an important component of a national strategy to reduce the increasing burden of CVD in China.

Serum Total and Lipoprotein Cholesterol Levels and Awareness, Treatment, and Control of Hypercholesterolemia in China

Background—Cardiovascular disease has become the leading cause of death in China. We examined the levels of serum total and lipoprotein cholesterol and status of awareness, treatment, and control of hypercholesterolemia in China. Methods and Results—A cross-sectional survey in a nationally representative sample of 15 540 Chinese adults 35 to 74 years of age was conducted during 2000 to 2001. Serum cholesterol was measured by use of standard methods, and information on treatment of hyperlipidemia was obtained by use of a standard questionnaire. Age-standardized mean levels of total, HDL, and LDL cholesterol and triglycerides were 186.1, 51.7, 109.5, and 128.1 mg/dL, respectively. Of the Chinese population 35 to 74 years of age, 23.8% (112 500 000 persons) had borderline high total cholesterol (200 to 239 mg/dL), and 9.0% (42 540 000 persons) had high total cholesterol (≥240 mg/dL). The population estimates for borderline high (130 to 159 mg/dL), high (160 to 189 mg/dL), and very high (≥190 mg/dL) LDL cholesterol were 17.0% (80 122 000 persons), 5.1% (24 329 000 persons), and 2.7% (12 822 000 persons), respectively. In addition, 19.2%, or 90 803 000 persons, had a low HDL cholesterol (<40 mg/dL). Among those who had a total cholesterol ≥200 mg/dL or who were on cholesterol-lowering medications, the proportion of men and women who were aware, treated, and controlled was only 8.8% and 7.5%, 3.5% and 3.4%, and 1.9% and 1.5%, respectively. Conclusions—The prevalence of hypercholesterolemia was relatively high and the percentage of adults with controlled blood cholesterol was low in China. Prevention and treatment of hypercholesterolemia should be an important component of a national strategy to reduce the substantial and increasing burden of cardiovascular disease in China.

Premature deaths attributable to blood pressure in China: a prospective cohort study

BACKGROUND Hypertension is a major global-health challenge because of its high prevalence and concomitant risks of cardiovascular disease. We estimated premature deaths attributable to increased blood pressure in China. METHODS We did a prospective cohort study in a nationally representative sample of 169,871 Chinese adults aged 40 years and older. Blood pressure and other risk factors were measured at a baseline examination in 1991 and follow-up assessment was done in 1999-2000. Premature death was defined as mortality before age 72 years in men and 75 years in women, which were the average life expectancies in China in 2005. We calculated the numbers of total and premature deaths attributable to blood pressure using population-attributable risk, mortality, and the population size of China in 2005. FINDINGS Hypertension and prehypertension were significantly associated with increased all-cause and cardiovascular mortality (p<0.0001). We estimated that in 2005, 2.33 million (95% CI 2.21-2.45) cardiovascular deaths were attributable to increased blood pressure in China: 2.11 million (2.03-2.20) in adults with hypertension and 0.22 million (0.19-0.25) in adults with prehypertension. Additionally, 1.27 million (1.18-1.36) premature cardiovascular deaths were attributable to raised blood pressure in China: 1.15 million (1.08-1.22) in adults with hypertension and 0.12 million (0.10-0.14) in adults with prehypertension. Most blood pressure-related deaths were caused by cerebrovascular diseases: 1.86 million (1.76-1.96) total deaths and 1.08 million (1.00-1.15) premature deaths. INTERPRETATION Increased blood pressure is the leading preventable risk factor for premature mortality in the Chinese general population. Prevention and control of this condition should receive top public-health priority in China. FUNDING American Heart Association (USA); National Heart, Lung, and Blood Institute, National Institutes of Health (USA); Ministry of Health (China); and Ministry of Science and Technology (China).

Prevalence and Risk Factors of Overweight and Obesity in China

Objective: To examine the prevalence and risk factors of overweight and obesity in China.

Prevalence of hypertension and its trends in Chinese populations

The third nation-wide survey of blood pressure level and hypertension was carried out in China in 1991. In total, 950,356 residents aged > or = 15 years were examined. Sampling population were composed of half urban and half rural from 27 provinces or autonomous regions and three municipalities. The results showed that: (1) the age-adjusted prevalence rate of hypertension (systolic blood pressure > or = 140 mmHg or diastolic blood pressure > or = 90 mmHg) was 11.26% (male 12.15%, female 10.32%) and the definite hypertension rate (systolic blood pressure > or = 160 mmHg or diastolic blood pressure > or = 95 mmHg, or on medication) was 5.29% (male 5.38%, female 5.21%); rate of borderline hypertension was evaluated from 2.82% to 6.15% during the 10-year period from 1979/1980 to 1991; (2) the prevalence rate was progressively increased with age, especially after age 35; prevalence rates were generally higher in men than women before about age 44, however by age 60, women had a higher prevalence of hypertension; (3) a general trend of decrease in prevalence from north-eastern to south-western China was confirmed; (4) there were significantly lower rates in rural than in urban areas. Results of preliminary analysis for prevalence of hypertension among different occupations, nationalities, and educational levels were presented.

Effect of omega-3 fatty acids supplementation on endothelial function: a meta-analysis of randomized controlled trials.

OBJECTIVE Inverse association was reported between omega-3 fatty acids (FAs) supplementation and the risk of cardiovascular disease. Identifying the effect of omega-3 FAs on endothelial function may contribute to explain the association. We conducted a meta-analysis to assess the effect of omega-3 FAs supplementation on endothelial function, as measured by flow-mediated dilation (FMD) and endothelium-independent vasodilation (EIV). METHODS Randomized placebo-controlled trials (RCTs) were identified from the databases of PubMed, EMBASE and Cochrane library by two investigators and the pooled effects were measured by weighted mean difference (WMD), together with 95% confidence intervals (CIs). Subgroup and meta-regression analyses were used to explore the source of between-study heterogeneity. RESULTS Totally 16 eligible studies involving 901 participants were finally included in meta-analysis. Compared with placebo, omega-3 FAs supplementation significantly increased FMD by 2.30% (95% CI: 0.89-3.72%, P = 0.001), at a dose ranging from 0.45 to 4.5 g/d over a median of 56 days. Subgroup analyses suggested that the effect of omega-3 FAs on FMD might be modified by the health status of the participants or the dose of supplementation. Sensitivity analyses indicated that the protective effect of omega-3 on endothelial function was robust. No significant change in EIV was observed after omega-3 FAs supplementation (WMD: 0.57%; 95% CI: -0.88 to 2.01%; P = 0.442). CONCLUSION Supplementation of omega-3 fatty acids significantly improves the endothelial function without affecting endothelium-independent dilation.