2型糖尿病患者血清视黄醇结合蛋白4水平及相关影响因素的研究

目的 探讨2型糖尿病(T2DM)患者血清视黄醇结合蛋白4(RBP4)的变化及其相关影响因素.方法 根据体重指数(BMI)将80例T2DM患者分为肥胖T2DM组(BMI≥25 k/m~2)、非肥胖T2DM组(BMI<25 kg/m~2),将30例正常体重非糖尿病者设为对照组.检测其空腹血清脂联素(APN)、RBP4、胰岛素(FINS)水平,同时测定空腹血糖(FBG)、身高、体重、腰围、臀围、糖化血红蛋白(HbA_1c)、三酰甘油(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C),计算BMI、腰臀比(WHR)和稳态模式评估法胰岛素抵抗指数(HOMA-IR).分析各组问RBP4水平的变化,并与上述其他指标进行相关分析.结果 RBP4在肥胖T2DM组和非肥胖T2DM组中显著高于对照组[分别为(30.02±5.32)、(20.10±5.45)、(12.02±3.45)mg/L](P<0.01),在肥胖T2DM组显著高于非肥胖T2DM组(P<0.01).单因素相关分析显示RBP4与TG、BMI、FBG、WHR、FINS、HOMA-IR呈正相关,与APN呈负相关(相关系数分别为0.225、0.697、0.323、0.557、0.272、0.461、-0.398).结论 血清RBP4在T2DM患者中显著升高,RBP4可能在胰岛素抵抗及T2DM的发生、发展过程中起了重要的作用.     

The diagnostic threshold of HbA1c and impact of its use on diabetes prevalence—A population-based survey of 6898 Han participants from southern China

Objective

The objective of this study is to determine the diagnostic threshold of HbA1c for diabetes and the impact of using it on diabetes prevalence.

Methods

A population-based stratified study was conducted in 2010 among community-dwelling adults aged ≥ 35 years in southern China. Participants without previously-diagnosed diabetes (PDD) took oral glucose tolerance test (OGTT) and HbA1c assay. HbA1c diagnostic threshold was determined by receiver operating characteristic curve.

Results

A total of 6989 participants with mean age of 52 years were recruited. The area under curve of HbA1c was 0.903 (95% CI: 0.883–0.922), with optimal cut-off value at 6.25% (sensitivity 75.6% and specificity 91.9%). There were 449 (6.42%) patients with PDD and 422 (6.04%), 815 (11.66%) and 918 (13.13%) new cases diagnosed by OGTT, HbA1c ≥ 6.25% or either, respectively. When either HbA1c or OGTT was used, newly-diagnosed diabetes prevalence increased by 117.4%.

Conclusions

Diabetes is prevalent in southern China. Near half of the patients go undetected with current diagnostic criteria. HbA1c ≥ 6.25% may be the diagnostic threshold value but needs further verification. The introduction of HbA1c threshold into diabetes diagnosis in China will cause a substantial increase in diabetes prevalence and great challenge on the public healthcare system.     

Estimate of a predictive cut-off value for serum 25-hydroxyvitamin D reflecting abdominal obesity in Korean adolescents

Vitamin D deficiency is a serious global issue. Although the serum 25-hydroxyvitamin D [25(OH)D] test is generally the most accurate way to assess vitamin D levels, the optimal range of 25(OH)D has yet to be established. Moreover, the optimal level may vary according to race, region, and age. Suboptimal vitamin D status is associated with obesity and metabolic syndrome, which are the major risk factors for cardiovascular disorders; however, these relationships in children and adolescents have yet to be clearly determined. Therefore, we identified the best predictive cut-off value for reflecting abdominal obesity and, based on this value, we investigated the relationship between suboptimal 25(OH)D status and the risk for having abdominal obesity, being overweight or obese, and having metabolic syndrome in Korean adolescents. We performed a cross-sectional analysis of 713 Korean adolescents, between 12-19 years of age, and used data collected from the 2008 Korea National Health and Nutrition Examination Survey (KNHANES). Receiver operation characteristic curve analysis was used to identify the cut-off value that reflected abdominal obesity. The cut-off value of serum 25(OH)D that reflected abdominal obesity in Korean adolescents was 17.6 ng/mL. After making adjustments for gender, age, and regular physical exercise, the group that had lower levels of serum 25(OH)D compared to the cut-off value had a significantly higher risk for abdominal obesity, obesity, and metabolic syndrome than the group with 25(OH)D levels higher than the cut-off value. Suboptimal vitamin D status based on this value is associated with increased risk for abdominal obesity, obesity, and metabolic syndrome among Korean adolescents.     

Adiposity measurements in association with metabolic syndrome in older men have different clinical implications

Obesity is a major public health problem, and measuring adiposity accurately and predicting its future comorbidities are important issues. Therefore, we hypothesized that 4 adiposity measurements, body mass index (BMI), waist circumference (WC), waist-to-height ratio, and body fat percentage, have different physiological meanings and distinct associations with adverse health consequences. This study aimed to investigate the relationship of these 4 measurements with metabolic syndrome (MetS) components and identify the most associated factor for MetS occurrence in older, non-medicated men. Cross-sectional data from 3004 men, all 65 years of age and older, were analyzed. The correlation and association between adiposity measurements and MetS components were evaluated by Pearson correlation and multiple linear regression. Based on multivariate logistic regression, BMI and WC were significantly associated with MetS and were selected to build a combined model of receiver operating characteristic curves to increase the diagnosis accuracy for MetS. The results show that BMI is independently associated with systolic and diastolic blood pressure; WC and body fat percentage are associated with fasting plasma glucose and log transformation of triglyceride; BMI and WC are negatively associated with high-density lipoprotein cholesterol (HDL-C); and WC is a better discriminate for MetS than BMI, although the combined model (WC + BMI) is not significantly better than WC alone. Based on these results, we conclude that the 4 adiposity measurements have different clinical implications. Thus, in older men, BMI is an important determinant for blood pressure and HDL-C. Waist circumference is associated with the risk of fasting plasma glucose, HDL-C, triglyceride, and MetS occurrence. The combined model did not increase the diagnosis accuracy.     

Dietary factors are associated with coronary heart disease risk factors in college students

It is hypothesized that healthy dietary and physical activity choices will be inversely associated with coronary heart disease (CHD) risk factors. Results from a cross-sectional study of 294 first-year University of Rhode Island students were used for the analyses. The presence of CHD risk factors was defined by the National Cholesterol Education Program Adult Treatment Panel III guidelines. Diet was assessed by three 24-hour food recalls, and physical activity was assessed by the International Physical Activity Questionnaire. Logistic regression models adjusted for sex estimated the odds of having CHD risk factors. A higher percent of kilocalories from alcohol was associated with a 9.9% increased risk for elevated triacylglycerol (odds ratio [OR], 1.099; 95% confidence interval [CI], 1.000-1.207). Sugar intake (OR, 1.015; 95% CI, 1.004-1.026), saccharin intake (OR, 1.047; 95% CI, 1.015-1.080), and body mass index (BMI; OR, 1.139; 95% CI, 1.037-1.252) were associated with an increased risk of low high-density lipoprotein cholesterol; dietary fiber intake (OR, 0.934; 95% CI, 0.873-1.000) was associated with a decreased risk of low high-density lipoprotein cholesterol. Participants with a higher BMI were 9.4% more likely to have elevated fasting glucose (OR, 1.094; 95% CI, 1.004-1.192) and 193.6% more likely to have a larger waist circumference (OR, 2.936; 95% CI, 1.543-5.586). Dietary factors and BMI are better indicators of CHD risk than physical activity is in this population.     

Waist circumference is positively correlated with markers of inflammation and negatively with adiponectin in women with metabolic syndrome

The purpose of this study was to correlate biomarkers of metabolic syndrome (MetS), with markers of inflammation and macronutrient intake in 89 women (25-72 years) with MetS. We hypothesized that waist circumference (WC) would have the stronger correlations with inflammatory parameters and would correlate with carbohydrate intake. Values for WC (108.7 ± 11.1 cm) and plasma triglycerides (202.7 ± 52.1 mg/dL) were elevated, whereas plasma glucose levels varied from 66 to 179 mg/dL, with 42% of women having insulin resistance. Plasma levels of interleukin 6 (0.2-15.9 mg/L), tumor necrosis factor α (1.47-12.3 mg/L), and high-sensitivity C-reactive protein (0.06-3.08 mg/dL) varied widely, with most women being above values considered normal. Subjects had high intake of total sugar (92.3 ± 56.4 g/d), high glycemic index (59.8 ± 6.5), and glycemic load (127.2 ± 56.1), whereas dietary fiber (17.1 ± 9.1 g/d) was below recommended intake. Waist circumference was positively correlated with insulin (r = 0.275, P < .01) and with the inflammatory markers interleukin 6 (r = 0.307, P < .01) and tumor necrosis factor α (r = 0.228, P < .05) and negatively correlated with plasma adiponectin (r = −0.309, P < .0001). In addition, WC was positively correlated with total carbohydrate, added sugar, and glycemic load (P < .05) but not with fat or protein. These results are consistent with central obesity being a key marker of the inflammatory state, and they also suggest that carbohydrates, particularly those that are digested rapidly, contribute to increased risk of central obesity and development of MetS.     

Dietary protein intake is associated with favorable cardiometabolic risk factors in adults: Tehran Lipid and Glucose Study

In this study, we investigated the hypothesis that dietary protein content and type are related to cardiometabolic risk factors including body mass index, waist circumference (WC), serum triglycerides, high-density lipoprotein cholesterol (HDL-C), serum fasting glucose, and blood pressure. This population-based study was conducted on 2537 subjects aged 19 to 70 years and selected from among participants of the Tehran Lipid and Glucose Study (2006-2008). Dietary data were collected using a validated semiquantitative food frequency questionnaire. Associations between intakes of total protein as well as the animal-to-plant (A/P) protein ratio and cardiometabolic risk factors were analyzed using multivariate linear regression models. Dietary protein intakes were 13.7% and 13.6% of energy, in men and women, respectively; the A/P protein ratio in women was significantly higher than in men (1.8±1.4 vs 1.4 ± 0.9). Body mass index was associated with total protein intake in men (β = 0.14, P = .01) and A/P protein ratio in women (β = 0.075, P = .01). Waist circumference was associated with total protein intake (β = −0.048, P = .03) and A/P protein ratio (β=0.031, P = .05) in women. Serum fasting glucose was associated with both total protein intake (β=0.061 and 0.11, P < .05) and the A/P proteinratio (β = −0.078 and −0.056, P < .05) in both men and women, respectively. Serum HDL-C was associated with total protein intake (β = 0.107 and 0.07, P < .05) in both men and women, whereas diastolic blood pressure in women was associated with total protein intake (β = −0.125, P = .01). In conclusion, higher dietary protein intake was associated with enhanced HDL-C levels, WC, and diastolic BP, and a higher ratio of A/P protein intake was related with lower serum fasting glucose andWC.     

Prevalence of metabolic syndrome and its influencing factors among the Chinese adults: The China Health and Nutrition Survey in 2009

Objective

We aimed to estimate the up-to-date prevalence of metabolic syndrome (MS) and its influencing factors among the Chinese adults.

Methods

Data were obtained from the China Health and Nutrition Survey conducted in 2009, which was a cross-sectional and partially nationally representative study including a total of 7488 Chinese adults (age ≥ 18 years).

Results

The overall age-standardized prevalence estimates of the MS were 21.3% (95%confidence interval (CI): 20.4%–22.2%), 18.2% (95%CI: 17.3%–19.1%) and 10.5% (95%CI: 9.8%–11.2%) based on definitions of revised NCEP ATPIII, IDF and CDS criteria, respectively. Individuals who were women (compared to men: odds ratio [OR] = 1.37, 95% CI = 1.16–1.61), 40 years or older (compared to less than 40 years old: OR = 2.82, 95%CI = 2.37–3.34 for 40–59 years; OR = 4.41, 95%CI = 3.68–5.29 for 60 years or older), overweight/obese (compared to normal weight: OR = 4.32, 95%CI = 3.77–4.95 for overweight; OR = 11.24, 95%CI = 9.53–13.26 for obese), and living in urban area (compared to living in rural area: OR = 1.27, 95%CI = 1.12–1.43) were more likely to have a higher prevalence estimate of MS. In addition, frequency of alcohol consumption and cigarette intake were also found to be significantly associated with probability of MS.

Conclusions

Our results suggest an urgent need to develop national strategies for the prevention, detection, treatment and control of obesity and MS in China.     

Candy consumption was not associated with body weight measures, risk factors for cardiovascular disease, or metabolic syndrome in US adults: NHANES 1999-2004

There is limited research examining the relationship of candy consumption by adults on diet and health. The purpose of this study was to determine total, chocolate, or sugar candy consumption and their effect on energy, saturated fatty acid and added sugar intake, weight, risk factors for cardiovascular disease, metabolic syndrome (MetS), and diet quality in adults 19 years and older (n = 15 023) participating in the 1999-2004 National Health and Nutrition Examination Survey. Twenty-four-hour dietary recalls were used to determine intake. Covariate-adjusted means ± SE and prevalence rates were determined for candy consumption groups. Odds ratios were used to determine the likelihood of cardiovascular risk factors and MetS. A total of 21.8%, 12.9%, and 10.9% of adults consumed total, chocolate, and sugar candy, respectively. Mean daily per capita intake of total, chocolate, and sugar candy was 9.0 ± 0.3, 5.7 ± 0.2, and 3.3 ± 0.2 g, respectively; intake in consumers was 38.3 ± 1.0, 39.9 ± 1.1, and 28.9 ± 1.3 g, respectively. Energy (9973 ± 92 vs 9027 ± 50 kJ; P < .0001), saturated fatty acid (27.9 ± 0.26 vs 26.9 ± 0.18 g; P = .0058), and added sugar (25.7 ± 0.42 vs 21.1 ± 0.41 g; P < .0001) intake were higher in candy consumers than nonconsumers. Body mass index (27.7 ± 0.15 vs 28.2 ± 0.12 kg/m²; P = .0092), waist circumference (92.3 ± 0.34 vs 96.5 ± 0.29 cm; P = .0051), and C-reactive protein (0.40 ± 0.01 vs 0.43 ± 0.01 mg/dL; P = .0487) levels were lower in candy consumers than nonconsumers. Candy consumers had a 14% decreased risk of elevated diastolic blood pressure (P = .0466); chocolate consumers had a 19% decreased risk of lower high-density lipoprotein cholesterol (P = .0364) and a 15% reduced risk of MetS (P = .0453). Results suggest that the current level of candy consumption was not associated with health risks.     

Cardiovascular risk factors in young,overweight, and obese European adults and associations with physical activity and omega-3 index

Excess body fat is associated with increased cardiovascular disease (CVD) risk. The hypothesis of the study was that physical activity and omega-3 index, a marker of past long chain n-3 polyunsaturated fatty acids consumption, counteract the negative associations between fatness and CVD risk factors in young overweight and obese adults. A total of 324 subjects (20-40 years, body mass index [BMI], 27.5-32.5 kg/m², from Iceland, Spain, and Ireland) were investigated cross-sectionally. Dietary intake, anthropometric measurements, blood pressure, CVD risk factors, and fatty acids in erythrocyte membrane were analyzed. Information on physical activity was collected. Linear models were constructed to find out the associations of BMI, physical activity (quartiles), and omega-3 index with CVD risk factors. The most frequently increased risk factors were blood lipids (41.4%) and blood pressure (32.1%); fewer participants experienced disturbed glucose metabolism (11.8%). Body mass index was significantly associated with increased CVD risk factors (P = .001-.029), with the exception of total cholesterol, low-density lipoprotein, and high-density lipoprotein. The highest physical activity quartile had a lower fat mass (P = .005, at a given BMI), leptin (P = .008, in male participants only), and interleukin 6 (P = .021) but higher high-density lipoprotein (P = .020) than other quartiles; however, an approximate dose-response relationship could only be observed for leptin. The omega-3 index was not associated with lower low-density lipoprotein (P = .056), but docosahexaenoic acid in erythrocyte membrane was associated to it (P = .016). It is concluded that physical activity and docosahexaenoic acid diminish some of the negative health effects associated with overweight and obesity; however, body fatness remains the most important variable associated with increased CVD risk factors in young overweight and obese adults.     

One hundred percent orange juice consumption is associated with better diet quality, improved nutrient adequacy, and no increased risk for overweight/obesity in children

The purpose of this study was to examine the association of 100% orange juice (OJ) consumption by children 2 to 18 years of age (n = 7250) participating in the 2003 to 2006 National Health and Nutrition Examination Survey with intakes of select nutrients, MyPyramid food groups, diet quality—measured by the Healthy Eating Index-2005, weight status, and associated risk factors. The National Cancer Institute method was used to estimate the usual intake of 100% OJ consumption, selected nutrients, and MyPyramid food groups. Percentages of the population below the Estimated Average Requirement were determined. Covariate adjusted logistic regression was used to determine if consumers had a lower odds ratio of being overweight or obese. Usual per capita intake of 100% OJ was 1.7 oz/d. Among consumers, the usual intake of 100% OJ for children (n = 2183; 26.2% of population) was 10.2 oz/d. Consumers had higher (P < .05) energy intakes than nonconsumers (9148 ± 113 vs 8625 ± 473 kJ). However, there were no differences in weight or body mass index in consumers and nonconsumers, and there was no significant difference in the risk of being overweight or obese between consumers and nonconsumers (odds ratio, 0.86; 95% confidence interval, 0.70-1.05). Compared with nonconsumers, consumers had a higher (P < .01) percentage (% ± SE) of the population meeting the Estimated Average Requirement for vitamin A (19.6 ± 2.0 vs 30.2 ± 1.4), vitamin C (0.0 ± 0.0 vs 29.2 ± 1.2), folate (1.3 ± 0.3 vs 5.1 ± 0.6), and magnesium (25.5 ± 2.0 vs 39.0 ± 11). The Healthy Eating Index-2005 was significantly (P < .01) higher in consumers (52.4 ± 0.4 vs 48.5 ± 0.3). Consumers also had higher intakes of total fruit, fruit juice, and whole fruit. Moderate consumption of 100% OJ should be encouraged in children as a component of a healthy diet.     

Dietary carbohydrate restriction improves insulin sensitivity,blood pressure,microvascular function,and cellular adhesion markers in individuals taking statins

Statins positively impact plasma low-density lipoprotein cholesterol, inflammation and vascular endothelial function (VEF). Carbohydrate restricted diets (CRD) improve atherogenic dyslipidemia, and similar to statins, have been shown to favorably affect markers of inflammation and VEF. No studies have examined whether a CRD provides additional benefit beyond that achieved by habitual statin use. We hypothesized that a CRD (<50 g carbohydrate/d) for 6 weeks would improve lipid profiles and insulin sensitivity, reduce blood pressure, decrease cellular adhesion and inflammatory biomarkers, and augment VEF (flow-mediated dilation and forearm blood flow) in statin users. Participants (n = 21; 59.3 ± 9.3 y, 29.5 ± 3.0 kg/m²) decreased total caloric intake by approximately 415 kcal at 6 weeks (P < .001). Daily nutrient intakes at baseline (46/36/17% carb/fat/pro) and averaged across the intervention (11/58/28% carb/fat/pro) demonstrated dietary compliance, with carbohydrate intake at baseline nearly 5-fold greater than during the intervention (P < .001). Compared to baseline, both systolic and diastolic blood pressure decreased after 3 and 6 weeks (P < .01). Peak forearm blood flow, but not flow-mediated dilation, increased at week 6 compared to baseline and week 3 (P ≤ .03). Serum triglyceride, insulin, soluble E-Selectin and intracellular adhesion molecule-1 decreased (P < .01) from baseline at week 3, and this effect was maintained at week 6. In conclusion, these findings demonstrate that individuals undergoing statin therapy experience additional improvements in metabolic and vascular health from a 6 weeks CRD as evidenced by increased insulin sensitivity and resistance vessel endothelial function, and decreased blood pressure, triglycerides, and adhesion molecules.     

Few favorable associations between fruit and vegetable intake and biomarkers for chronic disease risk in American adults

Using 24-hour dietary recall data from the National Health and Nutrition Examination Survey 1999 to 2006, the possible link between fruit and vegetable intake and chronic disease risk was assessed. C-reactive protein (CRP), low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), fasting plasma glucose (FPG), total cholesterol, and glycosylated hemoglobin were selected as biomarkers for chronic disease risk. It is hypothesized that individuals who consume more fruits and vegetables will have reduced chronic disease risk because of the healthful benefits of these foods. The objective of this study was to examine the relationship between fruit and vegetable consumption on selected biomarkers for chronic disease risk. Although some associations were significant for FPG, HDL-C, and low-density lipoprotein cholesterol in some of the models, no trend was present. After adjusting for demographic factors, socioeconomic factors, lifestyle factors, body mass index, total energy intake, and the presence of at least 1 of our 5 predetermined comorbidities, no associations of reduced or increased risk were observed in any quartiles of combined fruit and vegetable intake. Fruit and vegetable intakes were weakly associated with an increased HDL-C level and decreased FPG, glycosylated hemoglobin, and C-reactive protein levels in some of the models; however, no association was observed in the final model. Because selected biomarkers of future disease risk remained in reference ranges at both high and low intake and no significance was observed in the final model, no protective association was observed between fruit and vegetable intake and biomarkers for chronic disease risk. However, fruit and vegetable consumption is recommended as part of an overall healthy diet and to displace other energy-dense foods for weight maintenance, which can lead to a decrease in future disease risk.     

Green tea extract reduces blood pressure,inflammatory biomarkers,and oxidative stress and improves parameters associated with insulin resistance in obese,hypertensive patients

Green tea (GT) consumption is known to be associated with enhanced cardiovascular and metabolic health. The purpose of this study is to examine the hypothesis that supplementation with GT alters insulin resistance and associated cardiovascular risk factors in obese, hypertensive patients. In a double-blind, placebo-controlled trial, 56 obese, hypertensive subjects were randomized to receive a daily supplement of 1 capsule that contained either 379 mg of GT extract (GTE) or a matching placebo, for 3 months. At baseline and after 3 months of treatment, the anthropometric parameters, blood pressure, plasma lipid levels, glucose levels, creatinine levels, tumor necrosis factor α levels, C-reactive protein levels, total antioxidant status, and insulin levels were assessed. Insulin resistance was evaluated according to the homeostasis model assessment–insulin resistance protocol. After 3 months of supplementation, both systolic and diastolic blood pressures had significantly decreased in the GTE group as compared with the placebo group (P < .01). Considerable (P < .01) reductions in fasting serum glucose and insulin levels and insulin resistance were observed in the GTE group when compared with the placebo group. Serum tumor necrosis factor α and C-reactive protein were significantly lower, whereas total antioxidant status increased in the GTE group compared with the placebo (P < .05). Supplementation also contributed to significant (P < .05) decreases in the total and low-density lipoprotein cholesterol and triglycerides, but an increase in high-density lipoprotein cholesterol. In conclusion, daily supplementation with 379 mg of GTE favorably influences blood pressure, insulin resistance, inflammation and oxidative stress, and lipid profile in patients with obesity-related hypertension.