Components of the metabolic syndrome and incidence of diabetes in elderly Italians: the Italian Longitudinal Study on Aging

The aim of this study was to explore the relationship among components of the metabolic syndrome and their role in the development of diabetes. We included 2295 subjects, aged 65-84 years, participating in the Italian Longitudinal Study on Aging, a population-based study conducted in 1992 and with a follow-up in 1996. Factor analysis was conducted, separately for diabetic and non-diabetic men and women, using the principle components method and varimax rotations. Factor scores for the baseline were used as independent variables in logistic regressions models to determine risk factors predicting the development of diabetes. Factor analysis among non-diabetic elderly showed two factors for men (body size/insulin resistance, blood pressure/lipids) and three for women (body size, lipids, blood pressure). Among diabetic subjects, three factors emerged for men (body size/lipids/insulin resistance, body size/blood pressure, glucose) and four for women (body size/lipids/insulin resistance, lipids, body size/glucose/insulin resistance, lipids/blood pressure). For non-diabetic men and women, the body size factor (body size/insulin resistance factor for men) was strongly associated with diabetes incidence (OR=2.30, 95% CI 1.41-3.74 and OR=2.06, 95% CI 1.33-3.17, respectively). This study confirms that the metabolic syndrome (MetS) does not recognize one single underlying factor in an elderly cohort and that the obesity factor is a strong predictor of development of new onset diabetes.     

The metabolic syndrome and type 2 diabetes

The metabolic syndrome describes the clustering of dyslipidaemia, glucose intolerance and hypertension with central adiposity. The syndrome is increasing in prevalence worldwide as a consequence of increasing obesity prevalence. It will have global effects on the prevalence of cardiovascular disease. This review summarises current knowledge of the syndrome with special emphasis on the aetiology and pathogenesis and examines the clinical consequences of occlusive vascular disease and non alcoholic steatohepatitis. The roles of nutrition, exercise and pharmacological treatments of the syndrome are discussed.     

老年男性人群2型糖尿病与代谢综合征情况调查

目的　研究老年人群中 2型糖尿病和代谢综合征的患病和发病情况及其相互关系。方法　对 1 996～ 2 0 0 0年连续 5年健康查体的 2 1 59例男性老年人进行糖尿病筛查 ,检测血脂、心电图、坐位血压、身高、体重 ,建立数据库。各项代谢异常的诊断标准遵循WHO相关规定。结果　糖尿病、葡萄糖耐量降低 (IGT)、高血压、脂代谢异常、冠心病和肥胖的患病率分别为 2 7.8%、2 4 .6 %、61 .3 %、66 .6 %、71 .9%和 44 .8%。 1 996年新诊断糖尿病1 1 5例 ,1 997年 1 37例 ,1 998年 69例 ,1 999年 2 6例 ,2 0 0 0年 38例。以合并脂代谢异常、高血压、冠心病、肥胖各项分别为 1计数叠加 ,新诊断糖尿病的发病率在记数为“0”时是 5 .62 % ,“1”时 9.57% ,“2”时 1 5 .86 % ,“3”时 2 3 .41 % ,“4”时 30 .60 %。Logistic分析显示脂代谢异常、冠心病和高血压与糖尿病发病密切相关 (P <0 .0 1 ) ,脂代谢异常和冠心病与IGT发病密切相关 (P <0 .0 5)。本组老年人群中 ,未合并代谢综合征中各项异常者仅占 3 .3 %。结论　老年男性人群受代谢综合征影响大 ,各项异常患病率高 ,合并异常项目越多对新发糖尿病影响越大。冠心病患病率高是老年人群代谢综合征的特点     

Anthropometric parameters and metabolic syndrome in type 2 diabetes

To evaluate the value of body mass index (BMI) as predictor of waist circumference of cardiovascular risk (CRWC) and diagnostic of metabolic syndrome (MSWC) in patients with type 2 diabetes mellitus (DM 2), we assessed BMI and WC in 753 patients with DM 2 (472 women) with 23 +/- 8 years. The participants had been divided in groups in accordance with the presence or absence of ACCR or ACMS. The best BMI cut-off to predict such disturbances was evaluated in women and men. In females, BMI > or = 25.0 kg/m(2) was the best predictor of CRWC. Area under ROC curve and IC 95% were 0.7202 (0.6753 - 0.7652) for CRWC and of [0.8318 (0.7928 - 0.8708)] for MSWC. In males, IMC > or = 25.0 kg/m(2) was better predictor for CRWC presence [0.8527 (0.8098 - 0.8955)], while BMI > or = 30.0 kg/m(2) for MSWC [0.9071 (0.8708 - 0.9433)]. We conclude that BMI can be a simple way to evaluate metabolic syndrome and cardiovascular risk where there were not material and prepared professionals for the WC evaluation. We need prospective studies to evaluate if it is necessary to change the BMI cut-off adopted as indicative of these disturbances in the diabetic population.     

Components of the metabolic syndrome as predictors of cardiovascular disease and type 2 diabetes in middle-aged Japanese men

To determine whether the clustered features of the metabolic syndrome precede the 7 year incidence of cardiovascular disease (CVD) and type 2 diabetes, we examined 6182 Japanese male office workers aged 35-59 years without any history of CVD. The 5588 subjects without type 2 diabetes also constituted the nondiabetic cohort, and were re-examined over seven successive years. Components of the metabolic syndrome included glycemic disorder (type 2 diabetes for the risk of CVD and impaired fasting glucose for the risk of type 2 diabetes), systemic obesity, hypertension, dyslipidemia, proteinuria, and elevated white blood cell (WBC) count. After controlling for age, family history of diabetes, alcohol intake, and cigarette smoking, the multivariate-adjusted relative risk of incidence of CVD compared with absence of components was 3.18, 3.48, 12.55, and 14.15 (P for trend <0.001), for the presence of 1,2,3, and > or =4 components, respectively. The corresponding relative risks of incidence of type 2 diabetes were 1.92, 4.36, 6.44, and 15.08 (P for trend <0.001). In both non-smokers and current smokers, the multivariate-adjusted relative risks of incidence of CVD and type 2 diabetes increased as the number of components increased (P for trend <0.001 for all). Our findings indicate that clustered features of the metabolic syndrome are closely associated with development of CVD and type 2 diabetes in middle-aged Japanese.     

Serum uric acid associates with the incidence of type 2 diabetes in a prospective cohort of middle-aged and elderly Chinese

This study is to prospectively investigate the association between serum uric acid and the incidence of type 2 diabetes in middle-aged and elderly Chinese. This study consisted of 924 non-diabetic adults aged 40 years or older at baseline. Subjects who received antidiabetic therapies and those who responded positively to the 75-g oral glucose tolerance test according to the 1999 World Health Organization criteria were diagnosed as having type 2 diabetes. Ninety-eight subjects developed type 2 diabetes during the 3.5-year follow-up. The hazard ratio (HR) for incident diabetes was 1.50 [95% confidence interval (CI) 1.18-1.92] for the highest sex-specific quartile of serum uric acid compared with the lowest after controlling for confounders. Participants with hyperuricemia had an HR of 1.95 (95% CI 1.11-3.44) for incident diabetes compared with those without hyperuricemia. Compared with the lowest quartile, the highest quartile had an HR for incident diabetes of 2.45 (95% CI 1.39-4.33) in men and 1.39 (95% CI 1.04-1.84) in women after fully adjustment. Adding serum uric acid to a model of conventional risk factors for diabetes improved the area under the curve for prediction of type 2 diabetes by 5%. Serum uric acid was an independent predictor of incident type 2 diabetes in middle-aged and elderly Chinese.     

Lifestyle approach for type 2 diabetes and metabolic syndrome

Recent changes in lifestyle, including physical inactivity and unhealthy diets, are likely to have played an important role in the global epidemic of obesity, type 2 diabetes, and metabolic syndrome. Implementation of a healthier lifestyle, with an increase in physical activity and a reduction of body weight, based on the regulation of calories and fat intake, are the basis for the prevention and treatment of both type 2 diabetes and metabolic syndrome. Intervention studies based on changes in lifestyle in individuals at risk found that diabetes incidence was reduced by 42% to 63%. Similarly, intensive lifestyle changes in patients with the metabolic syndrome have been shown to reduce the prevalence of the syndrome by 20% to 48%. Reduction of body weight, improvement of the quality of diet, and promotion of physical activity are the main approaches to prevent and treat patients with type 2 diabetes or metabolic syndrome.     

Adiposity, type 2 diabetes and the metabolic syndrome in breast cancer

Upper body obesity and the related metabolic disorder type 2 diabetes have been identified as risk factors for breast cancer, and associated with late-stage disease and a poor prognosis. Components of the metabolic syndrome, including visceral adiposity, insulin resistance, hyperglycemia and hyperinsulinemia, with or without clinically manifest diabetes mellitus, low serum high-density lipoprotein cholesterol and hypertension have all been related to increased breast cancer risk. The biochemical mechanisms include extraglandular oestrogen production, reduced sex hormone-binding globulin with consequent elevation of the bioactive plasma free oestradiol and increased insulin biosynthesis, all of which exert mitogenic effects on both untransformed and neoplastic breast epithelial cells. Obesity, type 2 diabetes and the metabolic syndrome also have in common an increased production of leptin and a decreased production of adiponectin by adipose tissue, with consequent elevations and reductions, respectively, in the circulating levels of these two adipokines. These changes in plasma leptin and adiponectin, acting through endocrine and paracrine mechanisms, have been associated in several studies with an increase in breast cancer risk and, perhaps, to more aggressive tumours; studies in vitro showed that leptin stimulates, and adiponectin inhibits, tumour cell proliferation and the microvessel angiogenesis which is essential for breast cancer development and progression.     

代谢综合征各组分与老年人糖尿病关系的队列研究

目的 分析老年人代谢综合征(MS)及各组分与2型糖尿病(DM)发生的关系. 方法 队列研究,2007年对2001年参加调查的人群进行随访.用2005年国际DM联盟(IDF)颁布的全球统一标准诊断MS. 结果 基线MS与DM发生密切相关,RR(95% CI)为4.70(3.23～6.85).MS各组分与DM相关性最密切的是空腹血糖.单因素分析中.当血糖水平≥5.60 mmol/L时,RR(95% CI)高达9.68(6.59～14.23);在多因素分析中,当血糖水平为5.60～6.09 mmol/L时,RR值(95% CI)为5.49(3.38～8.92),而≥6.1 mmol/L时,RR值(95% CI)增大至14.44(9.29～22.44).当MS组分聚集数从1、2、3、4个上升到5个时,RR值可分别从2.92、5.67、12.28、19.52上升至37.83. 结论 MS增加患DM的风险,而空腹血糖增高同为DM发生重要的危险指标.     

Obstructive sleep apnea and the metabolic syndrome in an elderly healthy population: the SYNAPSE cohort

Background

Obstructive sleep apnea syndrome (OSA) has been recently considered as a cause and a component of the metabolic syndrome (MetS), previous studies showing the presence of OSA in about half of middle-aged patients having MetS. To date, no study has considered the association of OSA and MetS in the elderly. In this study we examine the prevalence of MetS and its strength association among healthy elderly OSA subjects.

Methods

A cohort of 806 subjects aged 68.5?years, participants of a 7-year follow-up study, was examined. All subjects underwent clinical evaluation, blood sample measurements, and an at-home polygraphy. OSA was assessed as an apnea/hypopnea index (AHI) >15, and MetS was diagnosed according to the Adult Treatment Panel III.

Results

In the total group, 9.8% of cases met criteria for MetS with a prevalence similar in men and women. Of the entire group with Mets, 51.3% were women and 48.7% men. OSA was diagnosed in 55.9% of the sample, and among the OSA group, 12.5% had MetS. Oxyhemoglobin desaturation index (ODI, p?p?=?0.003) were found significantly higher in subjects with MetS than in those without it. Most of MetS components were significantly associated with AHI and ODI, the relationship stronger with ODI. After adjustment for covariables such as obesity, gender, and presence of diabetes, ODI was independently associated with three MetS components, glycemia (p?p?=?0.002), and triglyceride levels (p?=?0.02). Sleepiness, autonomic arousal index, and sleep duration had no effect on the metabolic parameters.

Conclusions

In elderly subjects, the association between OSA and MetS was stronger for hyperglycemia and hypertension. Among factors explaining this association, hypoxemia appears to be the most important factor without any effect of indices of sleep fragmentation, sleep duration, and sleepiness.     

Adipogenic capacity and the susceptibility to type 2 diabetes and metabolic syndrome

To determine whether adipocyte storage capacity influences the onset and severity of type 2 diabetes and other components of the metabolic syndrome, we made normal and db/db mice resistant to obesity by overexpressing leptin receptor-b on the aP2-Lepr-b promoter. On a 4% diet, these mice have no phenotype, but on a 60% fat diet, they resist diet-induced obesity because constitutive adipocyte-specific overexpression of Lepr-b prevents obesity via the antilipogenic autocrine/paracrine action of leptin on adipocytes. After 8 months on the same 60% fat diet, body fat of transgenic mice was 70% below WT controls. Cardiac and liver fat was elevated in the transgenics, and their hyperinsulinemia was more marked, suggesting greater insulin resistance. The aP2-Lepr-b transgene also prevented obesity in db/db mice; at 10 weeks of age their body fat was half that of the db/db mice. This lack of obesity was attributable to reduced expression of sterol regulatory element binding protein-1c and its target lipogenic enzymes in adipose tissue and a 6-fold increase in Pref-1 mRNA. Severe diabetes was present in transgenics at 4 weeks of age, 10 weeks before db/db controls. Echocardiographic evidence of cardiomyopathy appeared at 10 weeks, weeks before the db/db mice. Histologically, loss of beta cells and myocardial fibrosis was present in the transgenic group at least 6 weeks before the db/db mice. These results suggest that the expression level of genes that regulate the adipogenic response to overnutrition profoundly influences the age of onset and severity of diet-induced type 2 diabetes and co-morbidities.     

三种代谢综合征定义在老年糖尿病人群中应用的比较

目的比较1999年世界卫生组织（WHO）、2001年美国胆固醇教育计划成人治疗组第三次报告（NCEP-ATPⅢ）和2005年国际糖尿病联盟（IDF）提出的3种代谢综合征（MS）定义在上海地区老年糖尿病人群中的适用性及异同。方法选择华山医院老年糖尿病患者896例,检测血糖、血脂、胰岛素、血压、身高、腰围、体重指数、腰臀比、胰岛素抵抗指数,分析3种定义标准诊断的MS患病率及其诊断一致性。以及与心脑血管疾病的关系。结果（1）WHO、ATPⅢ、IDF定义诊断的MS患病率分别为70.6%、56.1%和50.8%；ATPⅢ定义诊断出的中心性肥胖患病率低于其他2种定义；IDF定义诊断的MS组体重指数和腰围水平高于其他2种定义,ATPⅢ定义诊断的MS组HDL-C水平低于其他2种定义；（2）3种MS定义总体诊断符合率为65.7%,IDF与WHO定义的诊断符合率为70.8%,IDF与ATPⅢ定义的诊断符合率为70.1%；（3）IDF定义的MS组冠心病和脑梗死患病率高于其他2种定义。结论IDF诊断标准可能更适合本组老年糖尿病。     

高尿酸血症和2型糖尿病在代谢综合征中的作用

目的评价高尿酸血症和2型糖尿病(T2DM)在代谢综合征(MS)中的作用，并探讨其可能的作用机制。方法对124例高尿酸血症和56例血尿酸正常的T2DM患者的临床资料进行研究。结果高尿酸血症合并糖尿病组的体质指数(BMI)、甘油三酯(TG)以及冠心病和高血压病的患病率高于血糖正常组，且BMI、总胆固醇(TC)、TG以及冠心病和高血压病的患病率明显高于尿酸正常对照组。结论(1)高尿酸血症与肥胖、血脂异常明显相关。(2)高尿酸血症加重了T2DM患者的代谢紊乱，T2DM也使高尿酸血症患者的代谢紊乱加重，两者共同促进了动脉粥样硬化及冠心病和高血压病的发生。     

Higher regular fat dairy consumption is associated with lower incidence of metabolic syndrome but not type 2 diabetes

Background and aimsLimited evidence suggests habitual dairy consumption to be protective against metabolic syndrome (MetSyn) and type 2 diabetes among older adults. We assessed the association of baseline consumption of dairy products with the incidence of MetSyn and type 2 diabetes among a cohort of Australian adults aged 49 years and over.Methods and resultsA validated 145-item semi-quantitative food frequency questionnaire was used to assess food and nutrient intake at baseline. Ten-year incidence of MetSyn and type 2 diabetes were obtained from 1807 and 1824 subjects respectively. Odds ratios (OR) were calculated by discrete time logistic regression modelling. Compared with subjects in the lowest intake quartile of regular fat dairy products, those in the highest quartile had a 59% lower risk of MetSyn (multivariate adjusted OR: 0.41; 95% CI: 0.23–0.71; p_trend = 0.004), after adjustment for risk factors. Among obese subjects, an association between a high intake of regular fat dairy foods and reduced risk of type 2 diabetes was also found (age and sex adjusted OR 0.37; 95% CI: 0.16–0.88; p_trend = 0.030), but the association did not persist after adjustment for additional confounders. There was no association between total dairy consumption and risk of MetSyn or type 2 diabetes.ConclusionsWe found an inverse association between regular fat dairy consumption and risk of MetSyn among Australian older adults. Further studies are warranted to examine the association between weight status, dairy consumption and risk of type 2 diabetes.