Yufang Bi

Prevalence and Control of Diabetes in Chinese Adults

IMPORTANCE Noncommunicable chronic diseases have become the leading causes of mortality and disease burden worldwide. OBJECTIVE To investigate the prevalence of diabetes and glycemic control in the Chinese adult population. DESIGN, SETTING, AND PARTICIPANTS Using a complex, multistage, probability sampling design, we conducted a cross-sectional survey in a nationally representative sample of 98,658 Chinese adults in 2010. MAIN OUTCOMES AND MEASURES Plasma glucose and hemoglobin A1c levels were measured after at least a 10-hour overnight fast among all study participants, and a 2-hour oral glucose tolerance test was conducted among participants without a self-reported history of diagnosed diabetes. Diabetes and prediabetes were defined according to the 2010 American Diabetes Association criteria; whereas, a hemoglobin A1c level of <7.0% was considered adequate glycemic control. RESULTS The overall prevalence of diabetes was estimated to be 11.6% (95% CI, 11.3%-11.8%) in the Chinese adult population. The prevalence among men was 12.1% (95% CI, 11.7%-12.5%) and among women was 11.0% (95% CI, 10.7%-11.4%). The prevalence of previously diagnosed diabetes was estimated to be 3.5% (95% CI, 3.4%-3.6%) in the Chinese population: 3.6% (95% CI, 3.4%-3.8%) in men and 3.4% (95% CI, 3.2%-3.5%) in women. The prevalence of undiagnosed diabetes was 8.1% (95% CI, 7.9%-8.3%) in the Chinese population: 8.5% (95% CI, 8.2%-8.8%) in men and 7.7% (95% CI, 7.4%-8.0%) in women. In addition, the prevalence of prediabetes was estimated to be 50.1% (95% CI, 49.7%-50.6%) in Chinese adults: 52.1% (95% CI, 51.5%-52.7%) in men and 48.1% (95% CI, 47.6%-48.7%) in women. The prevalence of diabetes was higher in older age groups, in urban residents, and in persons living in economically developed regions. Among patients with diabetes, only 25.8% (95% CI, 24.9%-26.8%) received treatment for diabetes, and only 39.7% (95% CI, 37.6%-41.8%) of those treated had adequate glycemic control. CONCLUSIONS AND RELEVANCE The estimated prevalence of diabetes among a representative sample of Chinese adults was 11.6% and the prevalence of prediabetes was 50.1%. Projections based on sample weighting suggest this may represent up to 113.9 million Chinese adults with diabetes and 493.4 million with prediabetes. These findings indicate the importance of diabetes as a public health problem in China.

Urinary bisphenol A (BPA) concentration associates with obesity and insulin resistance.

CONTEXT Bisphenol A (BPA) is one of the worlds highest-volume chemicals in use today. Previous studies have suggested BPA disturbs body weight regulation and promotes obesity and insulin resistance. But epidemiological data in humans were limited. OBJECTIVE Our objective was to determine whether BPA associates with obesity and insulin resistance. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study included 3390 adults aged 40 yr or older, in Songnan Community, Baoshan District, Shanghai, China. MAIN OUTCOME MEASURES Questionnaire, clinical and biochemical measurements, and urinary BPA concentration were determined. Generalized overweight was defined as body mass index (BMI) of 24 to less than 28 kg/m(2) and obesity was defined as BMI of 28 kg/m(2) or higher. Abdominal obesity was defined as waist circumference at least 90 cm for men and at least 85 cm for women. Insulin resistance was defined as the index of homeostasis model assessment of insulin resistance higher than 2.50. RESULTS The participants in the highest quartile of BPA had the highest prevalence of generalized obesity [odds ratio (OR) = 1.50; 95% confidence interval (CI) = 1.15-1.97], abdominal obesity (OR = 1.28; 95% CI = 1.03-1.60), and insulin resistance (OR = 1.37; 95% CI = 1.06-1.77). In participants with BMI under 24 kg/m(2), compared with the lowest quartile, the highest quartile of BPA increased the prevalence of insulin resistance by 94% (OR = 1.94; 95% CI = 1.20-3.14), but this association was not observed in those with BMI of 24 kg/m(2) or higher. CONCLUSIONS BPA was positively associated with generalized obesity, abdominal obesity, and insulin resistance in middle-aged and elderly Chinese adults.

Relationship of urinary bisphenol A concentration to risk for prevalent type 2 diabetes in Chinese adults: a cross-sectional analysis.

BACKGROUND Greater bisphenol A exposure has been shown to be associated with a higher risk for self-reported adverse health outcomes, including diabetes. OBJECTIVE To examine the association between bisphenol A exposure and type 2 diabetes in adults. DESIGN Cross-sectional study. SETTING Songnan, Baoshan District, Shanghai, China. PARTICIPANTS 3423 local residents aged 40 years or older who were enrolled from 27 June 2008 to 10 August 2009. MEASUREMENTS Urinary concentrations of bisphenol A from morning spot urine samples (exposure) and fasting plasma glucose concentration, plasma glucose concentration 2 hours after an oral glucose tolerance test, and serum insulin concentration (outcomes). RESULTS Median age of the participants was 59.0 years (interquartile range, 53.0 to 68.7 years), 40% were men, and 1087 had type 2 diabetes. The median urinary bisphenol A level was 0.81 ng/mL (interquartile range, 0.47 to 1.43 ng/mL). Clinical characteristics differed between participants with normal glucose regulation and those with impaired glucose regulation and by bisphenol A quartile, but in multivariable analyses, there was no clear association between bisphenol A levels and type 2 diabetes. The adjusted odds ratio (OR) of type 2 diabetes was slightly increased for participants in the second bisphenol A quartile (0.48 to 0.81 ng/mL) (adjusted OR, 1.30 [95% CI, 1.03 to 1.64]) and the fourth quartile (>1.43 ng/mL) (adjusted OR, 1.37 [CI, 1.08 to 1.74]) but not the third quartile (0.82 to 1.43 ng/mL) (adjusted OR, 1.09 [CI, 0.86 to 1.39]), and a test of the trend of the association was not statistically significant. LIMITATIONS The cross-sectional study design and nonrandom sample of participants limit the conclusions that can be drawn. Many patients in the study already had diabetes, successful treatment of which could have obscured apparent associations. Dietary variables were not measured; however, this is necessary in observational studies of bisphenol A and diabetes because the presence of the chemical in the body may reflect consumption of sugared drinks in plastic bottles. CONCLUSION These findings do not confirm a previously reported association between urinary bisphenol A levels and self-reported type 2 diabetes.

Gut microbiome and serum metabolome alterations in obesity and after weight-loss intervention

Emerging evidence has linked the gut microbiome to human obesity. We performed a metagenome-wide association study and serum metabolomics profiling in a cohort of lean and obese, young, Chinese individuals. We identified obesity-associated gut microbial species linked to changes in circulating metabolites. The abundance of Bacteroides thetaiotaomicron, a glutamate-fermenting commensal, was markedly decreased in obese individuals and was inversely correlated with serum glutamate concentration. Consistently, gavage with B. thetaiotaomicron reduced plasma glutamate concentration and alleviated diet-induced body-weight gain and adiposity in mice. Furthermore, weight-loss intervention by bariatric surgery partially reversed obesity-associated microbial and metabolic alterations in obese individuals, including the decreased abundance of B. thetaiotaomicron and the elevated serum glutamate concentration. Our findings identify previously unknown links between intestinal microbiota alterations, circulating amino acids and obesity, suggesting that it may be possible to intervene in obesity by targeting the gut microbiota.

Combined Effects of 19 Common Variations on Type 2 Diabetes in Chinese: Results from Two Community-Based Studies

Background Many susceptible loci for type 2 diabetes mellitus (T2DM) have recently been identified from Caucasians through genome wide association studies (GWAS). We aimed to determine the association of 11 known loci with T2DM and impaired glucose regulation (IGR), individually and in combination, in Chinese. Methods/Principal Findings Subjects were enrolled in: (1) a case-control study including 1825 subjects with T2DM, 1487 with IGR and 2200 with normal glucose regulation; and (2) a prospective cohort with 734 non-diabetic subjects at baseline. The latter was followed up for 3.5 years, in which 67 subjects developed T2DM. Nineteen single nucleotide polymorphisms (SNPs) were selected to replicate in both studies. We found that CDKAL1 (rs7756992), SLC30A8 (rs13266634, rs2466293), CDKN2A/2B (rs10811661) and KCNQ1 (rs2237892) were associated with T2DM with odds ratio from 1.21 to 1.35. In the prospective study, the fourth quartile of risk scores based on the combined effects of the risk alleles had 3.05 folds (95% CI, 1.31–7.12) higher risk for incident T2DM as compared with the first quartile, after adjustment for age, gender, body mass index and diabetes family history. This combined effect was confirmed in the case-control study after the same adjustments. The addition of the risk scores to the model of clinical risk factors modestly improved discrimination for T2DM by 1.6% in the case-control study and 2.9% in the prospective study. Conclusions/Significance Our study provided further evidence for these GWAS derived SNPs as the genetic susceptible loci for T2DM in Chinese and extended this association to IGR.

Associations Between Age at Menarche and Menopause With Cardiovascular Disease, Diabetes, and Osteoporosis in Chinese Women

CONTEXT Ages at menarche and menopause are associated with cardiovascular disease (CVD), diabetes, and osteoporosis in Caucasian women, but associations remain unexplored in Chinese women. OBJECTIVE The purpose of this study was to assess associations between age at menarche and menopause with CVD, diabetes, and osteoporosis in Chinese women. DESIGN AND SETTING A cross-sectional, population-based study was conducted in Fujian, China, from June 2011 to January 2012. PARTICIPANTS Among 6242 women aged 21 to 92 years, 3304 postmenopausal women were enrolled, excluding premenopausal women (n = 2527), those with unreported ages at menarche and menopause (n = 138), those with unrecorded physical measurements (n = 203), and those with menarche age <8 years or >20 years (n = 70). MAIN OUTCOME MEASURES An oral glucose tolerance test, a 12-lead resting electrocardiogram, and calcaneus quantitative ultrasound were performed. RESULTS No significant associations were found between menarche age, diabetes, and osteoporosis (both P > .05); later menarche (>18 years) was significantly associated with lower CVD risk (odds ratio = 0.71, 95% confidence interval, 0.57-0.89; P = .002). Menopause age was not associated with diabetes; higher menopause age was associated with decreasing CVD risk (P for trend = .020) and earlier menopause (≤46 years) with significantly higher osteoporosis risk (odds ratio = 1.59, 95% confidence interval, 1.07-2.36; P = .023). CONCLUSIONS In China, ages at menarche and menopause are not associated with diabetes. Later menarche and menopause are associated with decreasing CVD risk and earlier menopause with higher osteoporosis risk. Menarche and menopause history may help identify women with increased risk of developing CVD and osteoporosis.

Cohort profile: Risk evaluation of cancers in Chinese diabetic individuals: A longitudinal (REACTION) study

To demonstrate whether abnormal glucose metabolism (diabetes and prediabetes) is associated with increased risk for cancer in the Chinese population and to identify factors that modify the risk of cancer among individuals with abnormal glucose metabolism.

Association between Nonalcoholic Fatty Liver Disease (NAFLD) and Osteoporotic Fracture in Middle-Aged and Elderly Chinese

CONTEXT Nonalcoholic fatty liver disease (NAFLD) has been considered as a hepatic manifestation of the metabolic syndrome and is associated with various metabolic abnormalities, which may link to an increased risk of osteoporotic fracture. However, epidemiological studies investigating the association between NAFLD and osteoporotic fracture were not available. OBJECTIVE The objective of the study was to determine whether NAFLD associates with osteoporotic fracture. DESIGN, SETTING, AND PARTICIPANTS This was a cross-sectional study of 7797 Chinese adults aged 40 yr or older in the Jiading District, Shanghai, China. MAIN OUTCOME MEASURES A questionnaire, anthropometric measurements, laboratory tests, and a hepatic ultrasonic examination were conducted. NAFLD was diagnosed by hepatic ultrasound after the exclusion of alcohol abuse and other liver diseases. A history of fractures was collected with an interviewer-assisted questionnaire. Osteoporotic fractures were defined as fractures that occurred due to low-trauma in 2 yr prior to the study. RESULTS Among men, the prevalence of osteoporotic fractures was significantly higher in those with NAFLD (3.6 vs. 1.7%, P = 0.003); however, no difference was found in women (3.4 vs. 2.6%, P = 0.14). The presence of NAFLD was significantly associated with increased odds of osteoporotic fracture among men (odds ratio 2.53; 95% confidence interval 1.26-5.07; P = 0.009) after controlling for potential confounders. The significant associations were not detected in women. CONCLUSIONS The presence of NAFLD was significantly associated with a recent history of osteoporotic fracture in middle-aged and elderly Chinese men.

Nonalcoholic Fatty Liver Disease Is Associated With Atherosclerosis in Middle-Aged and Elderly Chinese

Objective—To evaluate the associations between nonalcoholic fatty liver disease (NAFLD) and atherosclerosis. Methods and Results—A total of 8632 participants aged ≥40 years from Jiading district, Shanghai, were included in the present study. The presence of NAFLD was evaluated by ultrasonography. Carotid intima-media thickness (CIMT) and brachial-ankle pulse wave velocity (ba-PWV) were measured in each participant. The prevalence of NAFLD was 30.0% in the total population, with 30.3% in men and 29.9% in women, respectively. Subjects with NAFLD had remarkably higher CIMT and ba-PWV compared with those without NAFLD (0.594±0.105 mm versus 0.578±0.109 mm, P<0.0001; 1665±424 cm/s versus 1558±430 cm/s, P<0.0001). Subjects with both NAFLD and metabolic syndrome had significantly higher CIMT and ba-PWV compared with those with neither or either of these 2 diseases after adjustment for age and sex (all P<0.05). Logistic regressions also revealed that NAFLD conferred 35% and 30% increased odds ratios of elevated CIMT and ba-PWV, independent of conventional risk factors and the presence of metabolic syndrome. Conclusion—NAFLD was associated with elevated CIMT and ba-PWV, independent of conventional cardiovascular disease risk factors and metabolic syndrome. The effects of NAFLD and metabolic syndrome on atherosclerosis might not fully overlap.

Serum fetuin-A is correlated with metabolic syndrome in middle-aged and elderly Chinese.

OBJECTIVE Fetuin-A is an important player in the enhancement of insulin resistance. We aimed to investigate the association of serum fetuin-A and metabolic syndrome (MetS) in a community based Chinese population. METHODS A total of 5469 subjects aged 40 years or above were recruited from two urban communities in Shanghai. Demographic, anthropometric and biochemical features were collected according to a standard protocol. Serum fetuin-A levels were measured using ELISA and the modified NCEP-ATP III criteria were adopted to diagnose MetS. RESULTS A higher level of serum fetuin-A was well associated with a variety of metabolic disorders and an increased prevalence of MetS. The relative risks for MetS were markedly elevated in a dose-dependent manner both before and after extended adjustment in total participants (adjusted odds ratios were 1.00, 1.11, 1.20 and 1.40 for fetuin-A quartiles 1, 2, 3 and 4, respectively; P value for trend = 0.0002). MetS risks were also significantly associated with serum fetuin-A in various subgroups of sex, age, body mass index and glycaemic status. Moreover, an elevated serum fetuin-A was also independently associated with MetS components including central obesity, high blood pressure, high blood glucose and high triglycerides. Stepwise regression analyses revealed fetuin-A as an independent determinant of insulin resistance measured by the index of homeostasis model (HOMA-IR) (β = 0.064; P = 0.009). CONCLUSION Serum fetuin-A levels were strongly and independently associated with MetS and its components in community-dwelling Chinese adults.