Wenying Yang

Prevalence of Diabetes among Men and Women in China

BACKGROUND Because of the rapid change in lifestyle in China, there is concern that diabetes may become epidemic. We conducted a national study from June 2007 through May 2008 to estimate the prevalence of diabetes among Chinese adults. METHODS A nationally representative sample of 46,239 adults, 20 years of age or older, from 14 provinces and municipalities participated in the study. After an overnight fast, participants underwent an oral glucose-tolerance test, and fasting and 2-hour glucose levels were measured to identify undiagnosed diabetes and prediabetes (i.e., impaired fasting glucose or impaired glucose tolerance). Previously diagnosed diabetes was determined on the basis of self-report. RESULTS The age-standardized prevalences of total diabetes (which included both previously diagnosed diabetes and previously undiagnosed diabetes) and prediabetes were 9.7% (10.6% among men and 8.8% among women) and 15.5% (16.1% among men and 14.9% among women), respectively, accounting for 92.4 million adults with diabetes (50.2 million men and 42.2 million women) and 148.2 million adults with prediabetes (76.1 million men and 72.1 million women). The prevalence of diabetes increased with increasing age (3.2%, 11.5%, and 20.4% among persons who were 20 to 39, 40 to 59, and > or = 60 years of age, respectively) and with increasing weight (4.5%, 7.6%, 12.8%, and 18.5% among persons with a body-mass index [the weight in kilograms divided by the square of the height in meters] of < 18.5, 18.5 to 24.9, 25.0 to 29.9, and > or = 30.0, respectively). The prevalence of diabetes was higher among urban residents than among rural residents (11.4% vs. 8.2%). The prevalence of isolated impaired glucose tolerance was higher than that of isolated impaired fasting glucose (11.0% vs. 3.2% among men and 10.9% vs. 2.2% among women). CONCLUSIONS These results indicate that diabetes has become a major public health problem in China and that strategies aimed at the prevention and treatment of diabetes are needed.

The long-term effect of lifestyle interventions to prevent diabetes in the China Da Qing Diabetes Prevention Study: a 20-year follow-up study.

BACKGROUND Intensive lifestyle interventions can reduce the incidence of type 2 diabetes in people with impaired glucose tolerance, but how long these benefits extend beyond the period of active intervention, and whether such interventions reduce the risk of cardiovascular disease (CVD) and mortality, is unclear. We aimed to assess whether intensive lifestyle interventions have a long-term effect on the risk of diabetes, diabetes-related macrovascular and microvascular complications, and mortality. METHODS In 1986, 577 adults with impaired glucose tolerance from 33 clinics in China were randomly assigned to either the control group or to one of three lifestyle intervention groups (diet, exercise, or diet plus exercise). Active intervention took place over 6 years until 1992. In 2006, study participants were followed-up to assess the long-term effect of the interventions. The primary outcomes were diabetes incidence, CVD incidence and mortality, and all-cause mortality. FINDINGS Compared with control participants, those in the combined lifestyle intervention groups had a 51% lower incidence of diabetes (hazard rate ratio [HRR] 0.49; 95% CI 0.33-0.73) during the active intervention period and a 43% lower incidence (0.57; 0.41-0.81) over the 20 year period, controlled for age and clustering by clinic. The average annual incidence of diabetes was 7% for intervention participants versus 11% in control participants, with 20-year cumulative incidence of 80% in the intervention groups and 93% in the control group. Participants in the intervention group spent an average of 3.6 fewer years with diabetes than those in the control group. There was no significant difference between the intervention and control groups in the rate of first CVD events (HRR 0.98; 95% CI 0.71-1.37), CVD mortality (0.83; 0.48-1.40), and all-cause mortality (0.96; 0.65-1.41), but our study had limited statistical power to detect differences for these outcomes. INTERPRETATION Group-based lifestyle interventions over 6 years can prevent or delay diabetes for up to 14 years after the active intervention. However, whether lifestyle intervention also leads to reduced CVD and mortality remains unclear.

Prevalence of diabetes and its risk factors in China, 1994. National Diabetes Prevention and Control Cooperative Group

OBJECTIVE To determine the prevalence of diabetes and impaired glucose tolerance (IGT) and its risk factors in the Chinese population. RESEARCH DESIGN AND METHODS This study was a population-based cross-sectional study of 224,251 residents aged 25–64 years in 19 provinces and areas, including cities and rural areas of the north, south, east, and middle part of China. RESULTS Using the 1985 World Health Organization criteria, the prevalence of diabetes and IGT was 2.5 and 3.2%, respectively, in 213,515 subjects aged 25–64 years. Two thirds (70.3%) of the cases had newly recognized diabetes. The prevalence of diabetes in China is about three times higher than it was 10 years ago. On average, subjects with diabetes are older, have higher personal annual incomes, and more often have a family history of diabetes. They also have higher mean BMI, waist-to-hip ratio (WHR), systolic blood pressure, diastolic blood pressure, and a greater prevalence of hypertension. They perform less physical activity and have less education than people with normal oral glucose tolerance test results. Multiple logistic stepwise regression analysis shows that age, BMI (or WHR), family history of diabetes, hypertension, less physical activity, and higher annual income are independent risk factors of NIDDM, and that low education is also an independent risk factor of NIDDM in people with higher personal annual income. CONCLUSIONS The prevalence of diabetes in China is increasing with economic development and changes from traditional to modernized lifestyle, especially where people had lower level of education and socioeconomic development. Therefore, Chinese people should attempt to retain certain features of their traditional lifestyle (physical activity, healthy food, moderate body weight). Increased knowledge of risk factors for diabetes may help to prevent a further rapid increase in the prevalence of diabetes in China.

Cardiovascular mortality, all-cause mortality, and diabetes incidence after lifestyle intervention for people with impaired glucose tolerance in the Da Qing Diabetes Prevention Study: a 23-year follow-up study

BACKGROUND Lifestyle interventions among people with impaired glucose tolerance reduce the incidence of diabetes, but their effect on all-cause and cardiovascular disease mortality is unclear. We assessed the long-term effect of lifestyle intervention on long-term outcomes among adults with impaired glucose tolerance who participated in the Da Qing Diabetes Prevention Study. METHODS The study was a cluster randomised trial in which 33 clinics in Da Qing, China-serving 577 adults with impaired glucose tolerance-were randomised (1:1:1:1) to a control group or lifestyle intervention groups (diet or exercise or both). Patients were enrolled in 1986 and the intervention phase lasted for 6 years. In 2009, we followed up participants to assess the primary outcomes of cardiovascular mortality, all-cause mortality, and incidence of diabetes in the intention-to-treat population. FINDINGS Of the 577 patients, 439 were assigned to the intervention group and 138 were assigned to the control group (one refused baseline examination). 542 (94%) of 576 participants had complete data for mortality and 568 (99%) contributed data to the analysis. 174 participants died during the 23 years of follow-up (121 in the intervention group vs 53 in the control group). Cumulative incidence of cardiovascular disease mortality was 11.9% (95% CI 8.8-15.0) in the intervention group versus 19.6% (12.9-26.3) in the control group (hazard ratio [HR] 0.59, 95% CI 0.36-0.96; p=0.033). All-cause mortality was 28.1% (95% CI 23.9-32.4) versus 38.4% (30.3-46.5; HR 0.71, 95% CI 0.51-0.99; p=0.049). Incidence of diabetes was 72.6% (68.4-76.8) versus 89.9% (84.9-94.9; HR 0.55, 95% CI 0.40-0.76; p=0.001). INTERPRETATION A 6-year lifestyle intervention programme for Chinese people with impaired glucose tolerance can reduce incidence of cardiovascular and all-cause mortality and diabetes. These findings emphasise the long-term clinical benefits of lifestyle intervention for patients with impaired glucose tolerance and provide further justification for adoption of lifestyle interventions as public health measures to control the consequences of diabetes. FUNDING Centers for Disease Control and Prevention, WHO, the China-Japan Friendship Hospital, Da Qing First Hospital.

Prevalence of cardiovascular disease risk factor in the Chinese population: the 2007–2008 China National Diabetes and Metabolic Disorders Study

AIMS Cardiovascular disease (CVD) is now the most prevalent and debilitating disease affecting the Chinese population. The goal of the present manuscript was to analyse cardiovascular risk factors and the prevalence of non-fatal CVDs from data gathered from the 2007-2008 China National Diabetes and Metabolic Disorders Study. METHODS AND RESULTS A nationally representative sample of 46 239 adults, 20 years of age or older, was randomly recruited using a multistage stratified design method. Lifestyle factors, diagnosis of CVD, stroke, diabetes, and family history of each subject were collected, and an oral glucose tolerance test or a standard meal test was performed. Various non-fatal CVDs were reported by the subjects. SUDAAN software was used to perform all weighted statistical analyses, with P < 0.05 considered statistically significant. The prevalence of coronary heart disease, stroke, and CVDs was 0.74, 1.07, and 1.78% in males; and 0.51, 0.60, and 1.10% in females, respectively. The presence of CVDs increased with age in both males and females. The prevalence of being overweight or obese, hypertension, dyslipidaemia, or hyperglycaemia was 36.67, 30.09, 67.43, and 26.69% in males; and 29.77, 24.79, 63.98, and 23.62% in females, respectively. In the total sample of 46 239 patients, the prevalence of one subject having 1, 2, 3, or ≥4 of the 5 defined risk factors (i.e. smoking, overweight or obese, hypertension, dyslipidaemia, or hyperglycaemia) was 31.17, 27.38, 17.76, and 10.19%, respectively. Following adjustment for gender and age, the odds ratio of CVDs for those who had 1, 2, 3, or ≥4 risk factors was 2.36, 4.24, 4.88, and 7.22, respectively, when compared with patients with no risk factors. CONCLUSION Morbidity attributed to the five defined cardiovascular risk factors was high in the Chinese population, with multiple risk factors present in the same individual. Therefore, reasonable prevention strategies should be designed to attenuate the rapid rise in cardiovascular morbidity.

Comparison of vildagliptin and acarbose monotherapy in patients with Type 2 diabetes: a 24‐week, double‐blind, randomized trial

Aims  To compare the efficacy and tolerability of the dipeptidyl peptidase‐4 inhibitor, vildagliptin, with the alpha glucosidase inhibitor, acarbose, in drug‐naive patients with Type 2 diabetes.

Efficacy and safety of sitagliptin in the treatment of patients with type 2 diabetes in China, India, and Korea

The efficacy and safety of sitagliptin as monotherapy were evaluated in Chinese, Indian, and Korean patients with type 2 diabetes inadequately controlled by diet and exercise. In a randomized, placebo-controlled, double-blind, 18-week trial, 530 patients with HbA(1c) >or=7.5% and <or=11.0% (mean baseline 8.7%) received sitagliptin 100mg once daily or placebo. Compared with placebo, sitagliptin significantly (p<0.001) reduced mean HbA(1c) (-1.0%), fasting plasma glucose (-1.7 mmol/L), and 2-h postprandial glucose (-3.1 mmol/L), and a significantly (p<0.001) greater proportion of sitagliptin-treated versus placebo-treated patients achieved HbA(1c) <7% (20.6% versus 5.3%, respectively) at study end. Efficacy of sitagliptin was demonstrated in each country. Sitagliptin was generally well-tolerated. Clinical adverse events (AEs) were reported in 23.3% and 15.2% of sitagliptin-treated and placebo-treated patients, respectively. The difference was primarily due to increased gastrointestinal AEs in the sitagliptin group, most of which were mild and resolved on study drug. Serious AEs, discontinuations due to AEs, and drug-related AEs occurred with a low incidence in both groups. No hypoglycemia was reported. In conclusion, in this study, sitagliptin monotherapy for 18 weeks significantly improved glycemic control and was well-tolerated in patients with type 2 diabetes from China, India, and Korea.

Prevalence of Hypertension in China: A Cross-Sectional Study

Aims The present study aimed to assess the prevalence of hypertension among Chinese adults. Methods Data were obtained from sphygmomanometer measurements and a questionnaire administered to 46239 Chinese adults ≥20 years of age who participated in the 2007–2008 China National Diabetes and Metabolic Disorders Study. Hypertension was defined as blood pressure ≥140/90 mm Hg or use of antihypertensive medication. Results A total of 26.6% of Chinese adults had hypertension, and a significantly greater number of men were hypertensive than women (29.2% vs 24.1%, p<0.001). The age-specific prevalence of hypertension was 13.0%, 36.7%, and 56.5% among persons aged 20 to 44 years (young people), 45 to 64 years (middle-aged people), and ≥65 years (elderly people), respectively. In economically developed regions, the prevalence of hypertension was significantly higher among rural residents than among urban residents (31.3% vs 29.2%, p = 0.001). Among women or individuals who lived in the northern region, the disparity in the prevalence of hypertension between urban and rural areas disappeared (women: 24.0% vs. 24.0%, p = 0.942; northern region: 31.6% vs. 31.2%, p = 0.505). Among hypertensive patients, 45.0% were aware of their condition, 36.2% were treated, and 11.1% were adequately controlled. Conclusions The prevalence of hypertension in China is increasing. The trend of an increase in prevalence is striking in young people and rural populations. Hypertension awareness, treatment, and control are poor. Public health efforts for further improving awareness and enhancing effective control are urgently needed in China, especially in emerging populations.

Obesity, coronary heart disease risk factors and diabetes in Chinese: an approach to the criteria of obesity in the Chinese population.

The aim of this work was to study the relationship between excess body weight and the risks of hypertension and diabetes in the population of northeastern China. Subsections of a cross‐sectional survey in Da Qing City were used to assess the relationship of excess weight to risk factors for coronary heart disease (CHD). A 6‐year prospective study also assessed the probability of developing Type 2 diabetes. A total of 2856 adults (25–70 years of age) were assessed cross‐sectionally and 629 non‐diabetic subjects of similar age were followed‐up for 6 years. Blood pressure, plasma fasting glucose, triglycerides, high‐density lipoporotein (HDL) cholesterol and fibrinogen levels were measured as well as weight, height and waist and hip circumferences. About 45% of adults had a body mass index (BMI) of ≥25.0. Risk factors increased with increasing BMI from a baseline value of 21.0: at a BMI of 23.0–24.9, the risk of hypertension and hypertriglyceridaemia doubled; the risk increased threefold at a BMI of 25.0–26.9. The prevalence of Type 2 diabetes increased progressively in women within the normal BMI range and in men from a BMI of 25.0. Type 2 diabetes was four times as common if the BMI was >27.0. Increasing waist measurements predicted 10‐fold increases in hypertension and a three‐to‐five times increased risk of diabetes. Suitable waist cut‐off points were 85 cm for men and 80 cm for women, with statistical analysis showing waist as the more dominant predictor of risk than age, waist‐to‐hip ratios or BMIs. Hence, small increases in BMI, and particularly in waist circumference, predict a substantial increase in the risk of diabetes and risk for CHD, especially hypertension, in Chinese adults.

Effects of insulin resistance and insulin secretion on the efficacy of interventions to retard development of type 2 diabetes mellitus: the DA Qing IGT and Diabetes Study

OBJECTIVE To investigate the effects of insulin resistance (IR) and insulin secretion (IS) on the development of diabetes mellitus in individuals with impaired glucose tolerance (IGT) who underwent lifestyle interventions. METHODS 284 out of 577 individuals with IGT identified by population-based screening in Da Qing, China, who were randomized to undergo diet change and/or increased physical activity had baseline fasting and 2 h post-load insulin determinations. They were followed for 6 years for the development of diabetes. IR and IS were assessed using calculated indices based on fasting plasma insulin and glucose. The interactions of IR, IS, obesity and plasma glucose and the effects of the lifestyle interventions were evaluated using Cox Proportional Hazards analysis. RESULTS Both IR and IS were significantly associated with the development of diabetes. Lifestyle interventions were more effective in those with lower IT and higher IS at baseline. Diet plus exercise interventions resulted in significantly lower incidence of diabetes, even after controlling for IR, IS, BMI and 2hrPG. CONCLUSION Both IR and beta-cell function were predictors of diabetes in Chinese with IGT. Lifestyle intervention reduced the incidence of DM and these interventions were more effective in those with less IR.