Fructose-induced hypertension: essential role of chloride and fructose absorbing transporters PAT1 and Glut5

Increased dietary fructose in rodents recapitulates many aspects of the Metabolic Syndrome with hypertension, insulin resistance and dyslipidemia. Here we show that fructose increased jejunal NaCl and water absorption which was significantly decreased in mice whose apical chloride/base exchanger Slc26a6 (PAT1, CFEX) was knocked out. Increased dietary fructose intake enhanced expression of this transporter as well as the fructose-absorbing transporter Slc2a5 (Glut5) in the small intestine of wild type mice. Fructose feeding decreased salt excretion by the kidney and resulted in hypertension, a response almost abolished in the knockout mice. In parallel studies, a chloride-free diet blocked fructose-induced hypertension in Sprague Dawley rats. Serum uric acid remained unchanged in animals on increased fructose intake with hypertension. We suggest that fructose-induced hypertension is likely caused by increased salt absorption by the intestine and kidney and the transporters Slc26a6 and Slc2a5 are essential in this process.

Metabolic syndrome in peritoneal dialysis patients

Cardiovascular morbidity and mortality are common in peritoneal dialysis patients. Metabolic syndrome (MES) is a medical condition with a clustering of major risk factors for cardiovascular diseases. In this review article, the various diagnostic criteria used in MES are discussed. It is proposed to use a modified National Cholesterol Education Programme Adult Treatment Panel III (NCEP ATP III) criteria for the diagnosis of MES in peritoneal dialysis (PD) patients taking into consideration the scientific evidence and practicality. When three or more of the following criteria are satisfied in PD patients, obesity, high triglyceride, low high-density lipoprotein cholesterol (HDL-C), hypertension or dysglycaemia, they are diagnosed as having MES. Body mass index (BMI) with reference to ethnicity is suggested to replace waist circumference for diagnosing obesity. Epidemiology and outcome of PD patients with MES are highlighted. The adverse sequelae of obesity appear to be primarily due to fat mass rather than non-fat mass, possibly related to the pro-inflammatory effect of adipose tissue. Whilst there are therapies to tackle MES in PD patients, more conclusive data in human studies to see clinically improved outcomes with such strategies are needed.

Effect of bariatric surgery on the metabolic syndrome: a population-based, long-term controlled study

OBJECTIVE

To assess the effect of weight loss by bariatric surgery on the prevalence of the metabolic syndrome (MetS) and to examine predictors of MetS resolution.

PATIENTS AND METHODS

We performed a population-based, retrospective study of patients evaluated for bariatric surgery between January 1, 1990, and December 31, 2003, who had MetS as defined by the American Heart Association/National Heart, Lung, and Blood Institute (increased triglycerides, low high-density lipoprotein, increased blood pressure, increased fasting glucose, and a measure of obesity). Of these patients, 180 underwent Roux-en-Y gastric bypass, and 157 were assessed in a weight-reduction program but did not undergo surgery. We determined the change in MetS prevalence and used logistic regression models to determine predictors of MetS resolution. Mean follow-up was 3.4 years.

RESULTS

In the surgical group, all MetS components improved, and medication use decreased. Nonsurgical patients showed improvements in high-density lipoprotein cholesterol levels. After bariatric surgery, the number of patients with MetS decreased from 156 (87%) of 180 patients to 53 (29%); of the 157 nonsurgical patients, MetS prevalence decreased from 133 patients (85%) to 117 (75%). A relative risk reduction of 0.59 (95% confidence interval [CI], 0.48-0.67; P<.001) was observed in patients who underwent bariatric surgery and had MetS at follow-up. The number needed to treat with surgery to resolve 1 case of MetS was 2.1. Results were similar after excluding patients with diabetes or cardiovascular disease or after using diagnostic criteria other than body mass index for MetS. Significant predictors of MetS resolution included a 5% loss in excess weight (odds ratio, 1.26; 95% CI, 1.19-1.34; P<.001) and diabetes mellitus (odds ratio, 0.32; 95% CI, 0.15-0.68; P=.003).

CONCLUSION

Roux-en-Y gastric bypass induces considerable and persistent improvement in MetS prevalence. Our results suggest that reversibility of MetS depends more on the amount of excess weight lost than on other parameters.

Metabolic syndrome and the role of dietary lifestyles in Alzheimer's disease

Since Alzheimer's disease (AD) has no cure or preventive treatment, an urgent need exists to find a means of preventing, delaying the onset, or reversing the course of the disease. Clinical and epidemiological evidence suggests that lifestyle factors, especially nutrition, may be crucial in controlling AD. Unhealthy lifestyle choices lead to an increasing incidence of obesity, dyslipidemia and hypertension--components of the metabolic syndrome. These disorders can also be linked to AD. Recent research supports the hypothesis that calorie intake, among other non-genetic factors, can influence the risk of clinical dementia. In animal studies, high calorie intake in the form of saturated fat promoted AD-type amyloidosis, while calorie restriction via reduced carbohydrate intake prevented it. Pending further study, it is prudent to recommend to those at risk for AD--e.g. with a family history or features of metabolic syndrome, such as obesity, insulin insensitivity, etc.--to avoid foods and beverages with added sugars; to eat whole, unrefined foods with natural fats, especially fish, nuts and seeds, olives and olive oil; and to minimize foods that disrupt insulin and blood sugar balance.

Obstructive sleep apnea, hypoxia, and metabolic syndrome in psychiatric and nonpsychiatric settings

Obesity continues to be a serious cause of morbidity and mortality globally and particularly in North America. Primary manifestations of obesity include obstructive sleep apnea (OSA) and depression associated with a decrease in immune defense mechanisms, possibly related to increased cytokine levels. Secondary manisfestations of obesity possibly result from a cascade of events and include insulin resistance/ hyperglycemia, hyperlipidemia, and hypertension-all of which comprise metabolic syndrome. This paper reviews sleep disturbances in general and OSA in psychiatric patients, particularly those who are obese.

Transient prenatal androgen exposure produces metabolic syndrome in adult female rats

Androgen exposure during intrauterine life in nonhuman primates and in sheep results in a phenocopy of the reproductive and metabolic features of polycystic ovary syndrome (PCOS). Such exposure also results in reproductive features of PCOS in rodents. We investigated whether transient prenatal androgen treatment produced metabolic abnormalities in adult female rats and the mechanisms of these changes. Pregnant dams received free testosterone or vehicle injections during late gestation, and their female offspring were fed regular or high-fat diet (HFD). At 60 days of age, prenatally androgenized (PA) rats exhibited significantly increased body weight; parametrial and subcutaneous fat; serum insulin, cholesterol and triglyceride levels; and hepatic triglyceride content (all P < 0.0125). There were no significant differences in insulin sensitivity by intraperitoneal insulin tolerance test or insulin signaling in liver or skeletal muscle. HFD had similar effects to PA on body weight and composition as well as on circulating triglyceride levels. HFD further increased hepatic triglyceride content to a similar extent in both PA and control rats. In PA rats, HFD did not further increase circulating insulin, triglyceride, or cholesterol levels. In control rats, HFD increased insulin levels, but to a lesser extent than PA alone ( approximately 2.5- vs. approximately 12-fold, respectively). We conclude that transient prenatal androgen exposure produces features of the metabolic syndrome in adult female rats. Dyslipidemia and hepatic steatosis appear to be mediated by PA-induced increases in adiposity, whereas hyperinsulinemia appears to be a direct result of PA.

Regulation of the fructose transporter GLUT5 in health and disease

Fructose is now such an important component of human diets that increasing attention is being focused on the fructose transporter GLUT5. In this review, we describe the regulation of GLUT5 not only in the intestine and testis, where it was first discovered, but also in the kidney, skeletal muscle, fat tissue, and brain where increasing numbers of cell types have been found to have GLUT5. GLUT5 expression levels and fructose uptake rates are also significantly affected by diabetes, hypertension, obesity, and inflammation and seem to be induced during carcinogenesis, particularly in the mammary glands. We end by highlighting research areas that should yield information needed to better understand the role of GLUT5 during normal development, metabolic disturbances, and cancer.

Impact of the L-arginine-Nitric Oxide Pathway and Oxidative Stress on the Pathogenesis of the Metabolic Syndrome

The discovery of the physiological roles of nitric oxide has revolutionized the understanding of regulation of vascular tone, platelet adhesion and aggregation, and immune activation. Perhaps the most intriguing aspect of nitric oxide (NO) is that it is a gas that, in the absence of receptors, can regulate both normal physiological events and mediate cytotoxicity under pathological conditions. NO is produced from L-arginine by NO synthases (NOS), yielding L-citrulline and NO. The regulation of L-arginine pathway activity occurs at the level of NO production. The metabolic syndrome is a cluster of insulin resistance, elevated blood pressure, and atherogenic dyslipidemia, a common basis of cardiovascular disease. It occurs in genetically susceptible individuals with environmental influences and has serious economic and social consequences. Pharmacological and non-pharmacological therapies should be individualized and targeted to normalize its alterations of blood pressure, HDL cholesterol, triglycerides and glucose values. Despite the increasing prevalence of the metabolic syndrome in the last decades, there has been little progress in the understanding of the precise mechanisms involved in the pathogenesis of this syndrome and its complications. Emerging evidence is available that NO, inflammation and oxidative stress play important roles in the physiopathology of this syndrome. This review summarizes and evaluates the participation of the L-arginine-NO pathway and oxidative stress in the physiopathology of the metabolic syndrome and cardiovascular events at the systemic level, as well as the effects of exercise on this syndrome.

Elevated prevalence of obesity, metabolic syndrome, and cardiovascular risk factors in bipolar disorder

BACKGROUND

Bipolar disorder is associated with excess cardiovascular mortality. We hypothesized outpatients with bipolar disorder would exhibit excess cardiovascular risk factors, particularly among prevalent users of the second-generation antipsychotics associated with weight gain and valproic acid derivatives.

METHODS

This chart review of 217 patients with bipolar disorder examined cardiovascular risk factors of the metabolic syndrome. We also evaluated if certain medications were cross-sectionally associated with metabolic syndrome.

RESULTS

Fifty-six patients were not weighed and many did not have available lipid profiles. Over three-quarters of those with available data (n = 161) were overweight or obese (body mass index >or= 25) and nearly half were obese (body mass index >or= 30). A prevalence exceeding general population estimates was also observed for hypertriglyceridemia, elevated blood pressure/hypertension, and elevated fasting glucose/diabetes. Among those with all requisite data (n = 60), over 50% met criteria for National Cholesterol Education Program-defined metabolic syndrome, nearly double the expected prevalence. A trend toward greater prevalence of metabolic syndrome among prevalent users of the second-generation antipsychotics associated with weight gain was observed.

CONCLUSIONS

Obesity and the metabolic syndrome were common in patients with bipolar disorder. These patients may be under-evaluated for cardiovascular risk and warrant screening and early intervention.

Obstructive sleep apnea and cardiovascular disease: role of the metabolic syndrome and its components

Although obstructive sleep apnea and cardiovascular disease have common risk factors, epidemiologic studies show that sleep apnea increases risks for cardiovascular disease independently of individuals' demographic characteristics (i.e., age, sex, and race) or risk markers (i.e., smoking, alcohol, obesity, diabetes, dyslipidemia, atrial fibrillation, and hypertension). Individuals with severe sleep apnea are at increased risk for coronary artery disease, congestive heart failure, and stroke. The underlying mechanisms explaining associations between obstructive sleep apnea and cardiovascular disease are not entirely delineated. Several intermediary mechanisms might be involved including sustained sympathetic activation, intrathoracic pressure changes, and oxidative stress. Other abnormalities such as disorders in coagulation factors, endothelial damage, platelet activation, and increased inflammatory mediators might also play a role in the pathogenesis of cardiovascular disease. Linkage between obstructive sleep apnea and cardiovascular disease is corroborated by evidence that treatment of sleep apnea with continuous positive airway pressure reduces systolic blood pressure, improves left ventricular systolic function, and diminishes platelet activation. Several systematic studies are necessary to explicate complex associations between sleep apnea and cardiovascular disease, which may be compounded by the involvement of diseases comprising the metabolic syndrome (i.e., central obesity, hypertension, diabetes, and dyslipidemia). Large-scale, population-based studies testing causal models linking among sleep apnea, cardiovascular morbidity, and metabolic syndrome are needed.

Presence of the metabolic syndrome in obese adolescents predicts impaired glucose tolerance and nonalcoholic fatty liver disease

PURPOSE

To evaluate whether the presence of metabolic syndrome (MS) in obese adolescents is associated with other comorbidities of obesity

METHODS

A total of 85 obese teens (70% female and 30% male) with fasting insulin >25 microU/ml and family history of type 2 diabetes mellitus and/or acanthosis nigricans were studied. Mean age was 15.8 +/- 1.7 years and body mass index (BMI) was 39.3 +/- 6.6 kg/m(2). Of the subjects, 54% were Hispanic and 35% black, 5% white, 5% American Indian, and 1% Asian. Laboratory analysis included fasting lipids, glucose, gamma-glutamyl transpeptidase (GGT), and oral glucose tolerance testing. Additional liver transaminase levels were determined and liver ultrasound (US) was performed to evaluate the presence and severity of fatty liver.

RESULTS

All subjects met MS criteria for children for waist circumference, 49% for blood pressure, 54% for high-density lipoprotein, 54% for triglycerides, and 20% for impaired fasting glucose (IFG) or impaired glucose tolerance [IGT]). In all, 47 subjects had three or more MS criteria. BMI was no different between groups with and without MS. Subjects with three or more MS criteria were more likely to have IGT (p = .004), elevated alanine aminotransferase (p = .039), elevated GGT (p = .036), fatty liver on US (p < .001), and more severe fatty liver (p = .001).

CONCLUSIONS

Abnormal glucose regulation and evidence of nonalcoholic fatty liver disease (NAFLD) were more common in subjects meeting three criteria for MS than in those meeting fewer criteria. The identification of MS provides value to the primary care provider. Those patients meeting criteria for MS should be evaluated for glucose intolerance and NAFLD.

Nonalcoholic fatty liver disease in a district general hospital: clinical presentation and risk factors

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) affects one-fifth of the adult population and is currently the commonest liver problem in the western world. The prevalence of NAFLD is likely to rise over the coming decades in parallel to the obesity and diabetes epidemics. A retrospective study was undertaken in a UK. district general hospital (DGH) to determine the clinical and laboratory features of patients with NAFLD.

METHODS AND FINDINGS

A total of 48 patients with NAFLD were identified. Most (54%) were asymptomatic on presentation and 90% had an echogenic liver on ultrasonography (USS). Liver tests were elevated in the majority, but did not distinguish between simple steatosis and steatohepatitis. Having features of the metabolic syndrome and a low platelet count (P = 0.028) may help identify patients with advanced hepatic fibrosis.

CONCLUSIONS

NAFLD is common in the DGH and should be considered in all patients with metabolic risk factors. A liver biopsy should be considered in those with low platelets, type II diabetes mellitus, and the metabolic syndrome.

Liver fat is reproducibly measured using computed tomography in the Framingham Heart Study

BACKGROUND AND AIMS

Fatty liver is the hepatic manifestation of obesity, but community-based assessment of fatty liver among unselected patients is limited. We sought to determine the feasibility of and optimal protocol for quantifying fat content in the liver in the Framingham Heart Study using multidetector computed tomography (MDCT) scanning.

METHODS

Participants (n = 100, 49% women, mean age 59.4 years, mean body mass index 27.8 kg/m(2)) were drawn from the Framingham Heart Study cohort. Two readers measured the attenuation of the liver, spleen, paraspinal muscles, and an external standard from MDCT scans using multiple slices in chest and abdominal scans.

RESULTS

The mean measurement variation was larger within a single axial computed tomography (CT) slice than between multiple axial CT slices for the liver and spleen, whereas it was similar for the paraspinal muscles. Measurement variation in the liver, spleen, and paraspinal muscles was smaller in the abdomen than in the chest. Three versus six measures of attenuation in the liver and two versus three measures in the spleen gave reproducible measurements of tissue attenuation (intraclass correlation coefficient [ICCC] of 1 in the abdomen). Intra reader and interreader reproducibility (ICCC) of the liver-to-spleen ratio was 0.98 and 0.99, the liver-to-phantom ratio was 0.99 and 0.99, and the liver-to-muscle ratio was 0.93 and 0.86, respectively.

CONCLUSION

One cross-sectional slice is adequate to capture the majority of variance of fat content in the liver per individual. Abdominal scan measures as compared to chest scan measures of fat content in the liver are more precise. The measurement of fat content in the liver on MDCT scans is feasible and reproducible.

Identifying subjects with insulin resistance by using the modified criteria of metabolic syndrome

The objectives of this cohort analysis were to explore the relationship between insulin resistance (IR) and the criteria for metabolic syndrome (MetS) and to evaluate the ability to detect IR in subjects fulfilling those criteria. We enrolled 511 healthy subjects (218 men and 283 women) and measured their blood pressure (BP), body mass index, high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), and fasting plasma glucose levels. Insulin suppression testing was done to measure insulin sensitivity as the steady-state plasma glucose (SSPG) value. Subjects with an SSPG value within the top 25% were considered to have IR. The commonest abnormality was a low HDL-C level, followed by high BP. The sensitivity to detect IR in subjects with MetS was about 47%, with a positive predictive value of about 64.8%, which has higher in men than in women. In general, the addition of components to the criteria for MetS increased the predictive value for IR. The most common combination of components in subjects with MetS and IR were obesity, high BP, and low HDL-C levels. All of the components were positive except for HDL-C, which was negatively correlated with SSPG. The correlation was strongest for obesity, followed by high TG values. In subjects with MetS, sensitivity for IR was low. However, body mass index and TG values were associated with IR and may be important markers for IR in subjects with MetS.

Alpha-adrenoceptor-mediated vasoconstriction is not involved in impaired functional vasodilation in the obese Zucker rat

1. Obesity/metabolic syndrome is associated with augmented a-adrenoceptor sensitivity and impaired hyperaemic responses to exercise. Thus, it is possible that this elevated a-adrenoceptor constriction contributes to the blunted hyperaemic response. 2. Male lean and obese Zucker rats were instrumented for acute measurements of blood pressure (BP) and iliac blood flow (BF). Changes in BP and BF were determined in anaesthetized animals in response to intravenous administration of increasing doses of the a(1)-adrenoceptor agonist phenylephrine (PE). Once BF and BP returned to normal, a single bolus of the a-adrenoceptor antagonist phentolamine (0.5 mg) was administered. In separate animals, the spinotrapezius muscle was exteriorized for direct in situ observation of the microcirculation in response to phentolamine and muscle contraction. 3. Administration of PE demonstrated that iliac BF is highly autoregulated in the face of increasing perfusion pressure. Iliac conductance following phentolamine was significantly greater in obese rats. Following phentolamine administration, iliac vascular conductance was significantly greater in obese rats compared with lean animals. However, a-adrenoceptor blockade did not significantly alter arteriolar diameter in the spinotrapezius muscle during muscle contraction in either lean or obese animals. 4. These results suggest a greater contribution of the a-adrenoceptors in basal hindlimb vascular tone in obese rats. Furthermore, an augmented a-adrenoceptor-mediated vasoconstriction may not contribute to the impaired functional dilation in anaesthetized obese rats.

The relative risk of cardiovascular death among racial and ethnic minorities with metabolic syndrome: data from the NHANES-II mortality follow-up

The tendency for selected cardiovascular disease (CVD) risk factors to occur in clusters has led to the description of metabolic syndrome (MetS). The relative impact of the individual risk factor on the overall relative risk (RR) for cardiovascular death from metabolic syndrome is not well established and may differ across the different racial/ethnic groups. Using data from the National Health and Nutrition Examination Survey (NHANES II) mortality follow-up (NH2MS), we determined the prevalence and RR of cardiovascular death for individual components in the overall population and across racial and ethnic groups. The prevalence of MetS components varied significantly across gender and racial/ethnic groupings. The RR for CVD also varies for the number and different components of MetS. The adjusted RR for cardiovascular death was highest with diabetes (3.23; 95% CI: 2.70-3.88), elevated blood pressure (2.28; 95% CI: 1.94-2.67) and high triglycerides (1.63; 95% CI: 1.34-2.00). Although the RR for cardiovascular death differs significantly for some of the different components, the overall findings were similar across racial/ethnic groups. The two components that confer the highest risks for death are more prevalent in African Americans. We concluded that the RR of cardiovascular death associated with the diagnosis of MetS varies depending on the number and components used to establish the diagnosis of MetS and the racial/ethnic characteristic of the participants.

Metabolic syndrome and inflammatory responses to long-term particulate air pollutants

BACKGROUND

Human data linking inflammation with long-term particulate matter (PM) exposure are still lacking. Emerging evidence suggests that people with metabolic syndrome (MS) may be a more susceptible population.

OBJECTIVES

Our goal was to examine potential inflammatory responses associated with long-term PM exposure and MS-dependent susceptibility.

METHODS

We conducted secondary analyses of white blood cell (WBC) count and MS data from The Third National Health and Nutrition Examination Survey and PM10 (PM with aerodynamic diameter < 10 microm) data from the U.S. Environmental Protection Agency Aerometric Information Retrieval System. Estimated 1-year PM10 exposures were aggregated at the centroid of each residential census-block group, using distance-weighted averages from all monitors in the residing and adjoining counties. We restricted our analyses to adults (20-89 years of age) with normal WBC (4,000-11,000 x 10(6)/L), no existing cardiovascular disease, complete PM10 and MS data, and living in current residences > 1 year (n = 2,978; age 48.5 +/- 17.8 years). Mixed-effects models were constructed to account for autocorrelation and potential confounders.

RESULTS

After adjustment for demographics, socioeconomic factors, lifestyles, residential characteristics, and MS, we observed a statistically significant association between WBC count and estimated local PM10 levels (p = 0.035). Participants from the least polluted areas (1-year PM10 < 1st quartile cutoff: 27.8 mug/m3) had lower WBC counts than the others (difference = 145 x 10(6)/L; 95% confidence interval, 10-281). We also noted a graded association between PM10 and WBC across subpopulations with increasing MS components, with 91 x 10(6)/L difference in WBC for those with no MS versus 214, 338, and 461 x 10(6)/L for those with 3, 4, and 5 metabolic abnormalities (trend-test p = 0.15).

CONCLUSIONS

Our study revealed a positive association between long-term PM exposure and hematological markers of inflammation and supported the hypothesized MS-dependent susceptibility.

Association of insulin sensitivity and glucose tolerance with the c.825C>T variant of the G protein beta-3 subunit gene

The risk of macrovascular complications of diabetes mellitus is greatly enhanced by the presence of high blood pressure. In addition, hypertension and diabetes share insulin resistance as a common pathophysiological mechanism. Despite evidence for a common molecular genetic background of insulin resistance, glucose intolerance, and hypertension, few candidate genes have been shown to influence all of these features simultaneously. We examined the association of insulin sensitivity with the c.825C>T variant of the g-protein beta-3 subunit (GNB3), a candidate gene of hypertension, in families of Mexican-American hypertensive patients.

METHODS

One hundred eighty subjects enrolled in a family study of Mexican-American hypertensive patients were recruited from hypertension clinics in Los Angeles. Subjects underwent pretreatment blood pressure recording, an oral glucose tolerance test, euglycemic hyperinsulinemic clamp, and anthropometric measurements. DNA from peripheral blood leukocytes was genotyped by polymerase chain reaction and restriction enzyme digest with BseD1 (GNB). Statistical analysis was performed by transmission disequilibrium testing.

RESULTS

In carriers of the T-allele, blood glucose was significantly lower [(mean+S.D.) fasting: 96.7+22.9 vs. 106.7+51.7mg/dl, P=.009; oral glucose tolerance test (oGTT) 120 min: 131.7+48.7 vs. 137.8+64.9 mg/dl, P=.036], and insulin sensitivity was significantly higher (229.0+108.7 vs. 188.5+94.2 mg/kg per minute, P=.037) than in homozygous carriers of the C-allele. Blood pressure did not differ significantly between the phenotypes.

CONCLUSION

In a Mexican-American hypertensive population, we found evidence for higher insulin sensitivity in carriers of the T allele of the c.825C>T variant of GNB3.

Increasing overall physical activity and aerobic fitness is associated with improvements in metabolic risk: cohort analysis of the ProActive trial

AIMS/HYPOTHESIS

Our aim was to examine the association between change in physical activity energy expenditure (PAEE), total body movement (counts per day) and aerobic fitness (maximum oxygen consumption [VO2max] over 1 year and metabolic risk among individuals with a family history of diabetes.

METHODS

Three hundred and sixty-five offspring of people with type 2 diabetes underwent measurement of energy expenditure (PAEE measured using the flex heart rate method), total body movement (daily activity counts from accelerometry data), [VO2max] predicted from a submaximal graded treadmill exercise test and anthropometric and metabolic status at baseline and 1 year (n = 321) in the ProActive trial. Clustered metabolic risk was calculated by summing standardised values for waist circumference, fasting triacylglycerol, insulin and glucose, blood pressure and the inverse of HDL-cholesterol. Linear regression was used to quantify the association between changes in PAEE, total body movement and fitness and clustered metabolic risk at follow-up.

RESULTS

Participants increased their activity by 0.01 units PAEE kJ kg(-1) day(-1) over 1 year. Total body movement increased by an average of 9,848 counts per day. Change in total body movement (beta = -0.066, p = 0.004) and fitness (beta = -0.056, p = 0.003) was associated with clustered metabolic risk at follow-up, independently of age, sex, smoking status, socioeconomic status and baseline metabolic score.

CONCLUSIONS/INTERPRETATION

Small increases in activity and fitness were associated with a reduction in clustered metabolic risk in this cohort of carefully characterised at-risk individuals. Further research to quantify the reduction in risk of type 2 diabetes associated with feasible changes in these variables should inform preventive interventions.

A pilot study on the effect of Catha edulis Frosk., (Celastraceae) on metabolic syndrome in WOKW rats

This study investigated the effect of Catha edulis (khat) on some important parameters of the metabolic syndrome in Wistar Ottawa Karlsburg W (WOKW) rat. The animals were fed with the standard chow containing 5% air dried pulverized khat leaves for 14 days; followed by the standard chow for 16 days. The khat leaves were sorted into green (khat light; KL) and crimson (khat dark; KD) leaves. The control rats were fed on standard chow. Blood glucose (G), serum insulin, serum leptin and serum lipids (triglycerides, total cholesterol, HDL-, LDL-, and VLDL cholesterol) were determined. Feeding with khat leaves reduced the body weight and the triglyceride level of the animals. The effect of KD on these parameters was stronger than that of KL. KD lowered the blood glucose concentration and the leptin content whereas KL was inactive. The khat intake had no significant influence on serum insulin, total serum cholesterol, HDL-, LDL- and VLDL-cholesterol.

Change in metabolic syndrome parameters with antipsychotic treatment in the CATIE Schizophrenia Trial: prospective data from phase 1

BACKGROUND

The metabolic syndrome (MS) is associated with increased risk for diabetes mellitus and coronary heart disease, and is highly prevalent among schizophrenia patients. Given concerns over antipsychotic metabolic effects, this analysis explored MS status and outcomes in phase 1 of the CATIE Schizophrenia Trial.

METHODS

The change in proportion of subjects with MS and individual criteria was compared between antipsychotic treatment groups, along with mean changes for individual criteria. Primary analyses examined subjects with fasting laboratory assessments at baseline and 3 months. Other analyses examined 3-month changes in MS status, waist circumference (WC), HDL cholesterol and blood pressure in all subjects, metabolic changes at the end of phase 1 participation (EOP), and repeated measures changes in HDL, blood pressure (BP) and WC over phase 1.

RESULTS

At 3 months, there were no significant between-drug differences for the change in proportion of subjects meeting MS status or individual MS criteria in the smaller fasting cohort (n = 281) or for those meeting criteria for parameters not dependent on fasting status (BP, HDL, WC) among all subjects (n=660). Among all subjects whose MS status could be determined at 3 months (n=660), MS prevalence increased for olanzapine (from 34.8% to 43.9%), but decreased for ziprasidone (from 37.7% to 29.9%) (p=.001). Although effect sizes varied across subgroups, at 3 months olanzapine and quetiapine had the largest mean increase in waist circumference (0.7 in. for both) followed by risperidone (0.4 in.), compared to no change for ziprasidone (0.0 in.) and a decrease in waist circumference for perphenazine (-0.4 in.). Olanzapine also demonstrated significantly different changes in fasting triglycerides at 3 months (+21.5 mg/dl) compared to ziprasidone (-32.1 mg/dl). EOP exposure data was obtained, on average, nine months from baseline for all metabolic variables. Results from EOP and repeated measures analyses were consistent with those at 3 months for mean changes in WC and fasting triglycerides, but between group differences emerged for HDL and SBP.

CONCLUSIONS

This large non-industry sponsored study confirms the differential metabolic effects between antipsychotics. Clinicians are advised to monitor all metabolic parameters, including WC, HDL and serum triglycerides, during antipsychotic treatment.

Metabolic syndrome and sleep apnea

Metabolic syndrome is a disorder characterized by abdominal obesity, hypertension, increased triglycerides, decreased HDL cholesterol and increased blood glucose. Accumulating evidence strongly indicates that insulin resistance and an increased amount of abdominal fat are the pathogenic factors for the characteristics of metabolic syndrome. The metabolic syndrome is characterized by an increased risk for the development of cardiovascular disease and type 2 diabetes mellitus. Studies indicate that sleep apnea may be a manifestation of the metabolic syndrome. It has also been suggested that the metabolic syndrome or "syndrome X" should also comprise obstructive sleep apnea and should then be called syndrome "Z". It appears that obstructive sleep apnea and the metabolic syndrome are characterized by the same pathophysiologic environment, which increases the risk for the development of cardiovascular disease. The increased amount of visceral fat and the accompanying insulin resistance seem to be the main characteristics responsible for the development of obstructive sleep apnea and the metabolic syndrome.

The associations of total and differential white blood cell counts with obesity, hypertension, dyslipidemia and glucose intolerance in a Korean population

Although many studies have reported an association between total white blood cell count and metabolic syndrome, relatively few reports are available on the association between differential white blood cell counts and metabolic syndrome. The medical records of 15,654 subjects (age, median 46, range 14-90 yr; 8,380 men and 7,274 women) who visited the Center for Health Promotion were investigated. It was found that as total white blood cell (WBC) and differential WBC counts increased the frequencies of diabetes, hypertension, obesity, dyslipidemia, and metabolic syndrome also increased. Moreover, these significant relationships persisted after adjusting for age, gender, smoking, alcohol intake, educational background, and household income. The odds ratios (95% CI) for metabolic syndrome was 2.64 (2.30- 3.04) in the highest quartile of total WBC count, with corresponding figures of 2.14 (1.88-2.44) for neutrophils, 2.32 (2.03-2.64) for lymphocytes, 1.56 (1.37-1.78) for monocytes, 1.36 (1.20-1.54) for basophils, and 1.82 (1.59-2.08) for eosinophils versus the lowest quartiles of the appropriate total and differential counts, respectively, after adjusting for the variables mentioned above. These independent associations were also observed by subgroup analyses according to the smoking status. Our data suggest that even within normal ranges, total WBC count and the differential WBC counts are associated with the presence of metabolic syndrome.

Regional differences in the prevalence of the metabolic syndrome in primary care practices in Germany

INTRODUCTION

Data on the prevalence and regional distribution of the metabolic syndrome in Germany are lacking, in particular for primary care.

METHODS

In October 2005 anthropometric measurements were taken from 35 869 consecutive patients aged 18 to 99 years, in 1511 primary care practices. Waist circumference, blood pressure, lifestyle, and past medical history were assessed and blood tests taken (HDL-, LDL- and total cholesterol, triglycerides, glucose). Crude and age-standardized prevalence were calculated.

RESULTS

Women in the eastern part of Germany showed a higher age-standardized prevalence of the metabolic syndrome than women in the western part (21.1%; 95% CI: 19.9 to 22.4 respectively 17.7%; 95% CI: 17.2 to 18.3). In men the prevalences were 22.7% (95% CI: 20.9 to 24.4) and 21.4% (95% CI: 20.6 to 22.1) respectively. Patients from Saxony-Anhalt, Brandenburg, and Mecklenburg-Western Pomerania showed the highest prevalence, while women in Hamburg, Berlin, and Hesse and men in Schleswig-Holstein, Saarland, and Hamburg showed the lowest prevalence. Cardiovascular disease prevalence was comparable, while diabetes prevalence was higher in patients from eastern Germany (17% vs.13% in men; 12% vs. 9% in women).

DISCUSSION

The prevalence of the metabolic syndrome in German primary care is high. Prevention efforts should focus in particular on differences in gender, socioeconomic status, and region.

Cardiometabolic risk factors assessed by a finger stick dried blood spot method

BACKGROUND

Cardiovascular and metabolic risk factors are gaining attention as potential indicators for intervention in the prevention and treatment of cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM). Blood spot technology offers an efficient, convenient method to measure these risk factors in an at-risk population. Simple and convenient methods to assess cardiometabolic risk factors will allow clinicians to formulate treatment strategies for effective prevention and management of these conditions.

METHOD

Insulin and high sensitivity C-reactive protein (hs-CRP) were measured in dried blood spot and corresponding serum samples using conventional commercial serum kits based on a direct sandwich ELISA technique. The triglyceride assay involved enzymatic hydrolysis of triglycerides by lipase to glycerol and free fatty acids. The glycerol produced was then measured by coupled enzyme reactions. Blood spot assays were modified from previously published methods to give improved accuracy and turnaround time.

RESULTS

Blood spot levels correlated well with serum levels of hs-CRP (r = 0.99), triglycerides (fasting, r = 0.95; nonfasting, r = 0.94), and insulin (fasting, r = 0.93; nonfasting, r = 0.97).

CONCLUSION

Blood spot testing for insulin, hs-CRP, and triglycerides may be helpful in the cardiometabolic screening or monitoring of patients at risk of developing CVD, T2DM, or metabolic syndrome.

Low phytoestrogen levels in feed increase fetal serum estradiol resulting in the "fetal estrogenization syndrome" and obesity in CD-1 mice

BACKGROUND

Although estrogenic chemicals can disrupt development of the reproductive system, there is debate about whether phytoestrogens in soy are beneficial, benign, or harmful.

OBJECTIVES

We compared reproductive and metabolic characteristics in male and female mice reared and maintained on non-soy low-phytoestrogen feed or soy-based high-phytoestrogen feed.

METHODS

The low-phytoestrogen diet was non-soy PMI 5K96 (verified casein diet), and the high-phytoestrogen diet consisted of soy-based PMI 5008 during pregnancy and lactation and soy-based PMI 5001 maintenance feed after weaning.

RESULTS

In fetuses whose mothers consumed the low-phytoestrogen PMI 5K96 feed, we found a paradoxical significant elevation in endogenous serum estradiol, which was associated postnatally with adverse reproductive outcomes referred to as the "fetal estrogenization syndrome (FES)". In females, this syndrome included early puberty and increased uterine responsiveness to estrogen, and in males, it included reduced testis, epididymis, and seminal vesicle size, but an enlarged prostate. The low-phytoestrogen-fed males and females were lighter at birth, but, between weaning and adulthood, they became obese and developed abnormally high serum leptin levels; these males, but not females, showed impaired glucose regulation.

CONCLUSIONS

Removing phytoestrogens from mouse feed produces an obese phenotype consistent with metabolic syndrome, and the associated reproductive system abnormalities are consistent with FES due to elevated endogenous fetal estradiol. Laboratory rodents may have become adapted to high-phytoestrogen intake over many generations of being fed soy-based commercial feed; removing all phytoestrogens from feed leads to alterations that could disrupt many types of biomedical research.

HIV-protease inhibitors induce expression of suppressor of cytokine signaling-1 in insulin-sensitive tissues and promote insulin resistance and type 2 diabetes mellitus

Insulin resistance, hyperglycemia, and type 2 diabetes are among the sequelae of metabolic syndromes that occur in 60-80% of human immunodeficiency virus (HIV)-positive patients treated with HIV-protease inhibitors (PIs). Studies to elucidate the molecular mechanism(s) contributing to these changes, however, have mainly focused on acute, in vitro actions of PIs. Here, we examined the chronic (7 wk) in vivo effects of the PI indinavir (IDV) in male Zucker diabetic fatty (fa/fa) (ZDF) rats. IDV exposure accelerated the diabetic state and dramatically exacerbated hyperglycemia and oral glucose intolerance in the ZDF rats, compared with vehicle-treated ZDF rats. Oligonucleotide gene array analyses revealed upregulation of suppressor of cytokine signaling-1 (SOCS-1) expression in insulin-sensitive tissues of IDV rats. SOCS-1 is a known inducer of insulin resistance and diabetes, and immunoblotting analyses revealed increases in SOCS-1 protein expression in adipose, skeletal muscle, and liver tissues of IDV-administered ZDF rats. This was associated with increases in the upstream regulator TNF-alpha and downstream effector sterol regulatory element-binding protein-1 and a decrease in IRS-2. IDV and other PIs currently in clinical use induced the SOCS-1 signaling cascade also in L6 myotubes and 3T3-L1 adipocytes exposed acutely to PIs under normal culturing conditions and in tissues from Zucker wild-type lean control rats administered PIs for 3 wk, suggesting an effect of these drugs even in the absence of background hyperglycemia/hyperlipidemia. Our findings therefore indicate that induction of the SOCS-1 signaling cascade by PIs could be an important contributing factor in the development of metabolic dysregulation associated with long-term exposures to HIV-PIs.

Rimonabant: the evidence for its use in the treatment of obesity and the metabolic syndrome

INTRODUCTION

Obesity and overweight affect over 1 billion people worldwide and are leading causes of morbidity and mortality. Clinical features of obesity converge with those of the metabolic syndrome and type 2 diabetes, greatly increasing the risk of long-term adverse outcomes.

AIMS

To review the evidence on rimonabant, a novel CB1 receptor antagonist, for the treatment of obese and overweight patients.

EVIDENCE REVIEW

There is clear evidence that rimonabant 20 mg/day in conjunction with a hypocaloric diet causes a mean weight loss of 4.6 kg in obese and overweight patients after 1 year's treatment, with approximately 50% of patients achieving a weight loss of ≥5%. One study demonstrated that weight loss is maintained for up to 2 years. The drug also improves lipid and glycemic cardiovascular risk factors, including high-density lipoprotein cholesterol and insulin resistance, and reduces waist circumference, thus reducing the prevalence of metabolic syndrome. Treatment of obese and overweight diabetic patients with rimonabant decreases glycosylated hemoglobin (HbA(1c)), including patients previously untreated for diabetes. The effect of rimonabant appears to be partly independent of weight loss. Rimonabant 20 mg/day is generally well tolerated, with mild to moderate transient adverse effects including nausea, diarrhea, dizziness, and anxiety. Approximately 14% of patients receiving rimonabant 20 mg/day discontinued due to adverse effects, primarily depressed mood, although overall rates of depression did not differ significantly compared with placebo.

PLACE IN THERAPY

The evidence supports the use of rimonabant 20 mg/day along with dietary modification to reduce cardiovascular risk factors in obese and overweight patients, including those with diabetes. The drug is contraindicated in patients receiving antidepressants. Long-term data on cardiovascular outcomes, morbidity, and mortality are eagerly awaited.

Increase of metabolic syndrome score is an independent determinant of increasing pulse pressure

PURPOSE

The objective of this study was to determine whether the progressive increase of metabolic syndrome (MetS) score, the number of components of MetS, is correlated significantly with increasing pulse pressure (PP).

MATERIALS AND METHODS

4,034 subjects were enrolled from the Cardiovascular Genome Center of Yonsei University (M:F=2344:1690, 55.2 +/- 10.5). Most of the study population were recruited from hypertension clinics, controlled with medications according to JNC7 guidelines. The Asian modified criteria of MetS were applied and MetS score was estimated. The HOMA index for insulin resistance, cholesterol profiles, and anthropometric measurements were assessed.

RESULTS

Among 4034 participants, 1690 (41.9%) were classified as MetS. Progressive increase in PP was demonstrated for increasing components of the MetS score. Multiple linear regression analysis with PP as the dependent variable showed that age (beta = 0.311, p < 0.001), MetS score (beta = 0.226, p < 0.001), male gender (beta = -0.093, p < 0.001) and HOMA index IR (beta = 0.033, p = 0.03) are significantly associated with PP (R2 = 0.207, p < 0.001).

CONCLUSION

The present results from this study demonstrate that increasing MetS score is an independent determinant of increasing PP. The results also demonstrate the independent role of MetS in increasing arterial stiffness and PP.

Examining metabolic syndrome definitions in overweight Hispanic youth: a focus on insulin resistance

OBJECTIVE

To examine the prevalence of the metabolic syndrome in overweight Hispanic youth according to 3 published pediatric definitions. Furthermore, the relationship of each definition to directly measured insulin resistance was examined.

STUDY DESIGN

We conducted a secondary data analysis of 218 overweight Hispanic youth with a family history of type 2 diabetes mellitus. The metabolic syndrome was defined as >/=3 of these criteria: elevated triglyceride level, low high-density lipoprotein cholesterol level, elevated blood pressure, abdominal obesity, and hyperglycemia. The cutoff points were derived from updated definitions of Cook et al,(1) Cruz et al,(2) and Weiss et al.(3) Insulin sensitivity was determined with the insulin-modified frequently sampled intravenous glucose tolerance test.

RESULTS

Prevalence of the metabolic syndrome ranged from 25.7% to 39%, with moderate to substantial agreement between definitions (kappa = 0.52-0.70). Regardless of definition, an inverse relationship between metabolic risk and insulin sensitivity was noted such that children with the metabolic syndrome had 51% to 60% lower insulin sensitivity compared with children without any risk factors (P </=.001 for all definitions).

CONCLUSION

The metabolic syndrome is prevalent in overweight Hispanic youth and may provide pediatricians with additional clinical insight for identifying the most metabolically at-risk children. Working toward a uniform and practical definition of the metabolic syndrome may improve its clinical implementation.

HbA1c measured in stored erythrocytes and mortality rate among middle-aged and older women

AIMS/HYPOTHESIS

Diabetes is known to increase mortality rate, but the degree to which mild hyperglycaemia may be associated with the risk of death is uncertain. We examined the association between HbA1c measured in stored erythrocytes and mortality rate in women with and without diabetes.

METHODS

We conducted a cohort study of 27,210 women>or=45 years old with no history of cardiovascular disease or cancer who participated in the Women's Health Study, a randomised trial of vitamin E and aspirin.

RESULTS

Over a median of 10 years of follow-up, 706 women died. Proportional hazards models adjusted for age, smoking, hypertension, blood lipids, exercise, postmenopausal hormone use, multivitamin use and C-reactive protein were used to estimate the relative risk of mortality. Among women without a diagnosis of diabetes and HbA1c<5.60%, those in the top quintile (HbA1c 5.19-5.59%) had a relative risk of mortality of 1.28 (95% CI 0.98-1.69, p value for linear trend=0.14) compared with those with HbA1c 2.27-4.79%. Women with HbA1c 5.60-5.99% and no diagnosis of diabetes had a 54% increased risk of mortality (95% CI 1-136%) compared with those with HbA1c 2.27-4.79%. HbA1c was significantly associated with mortality across the range 4.50-7.00% (p value for linear trend=0.02); a test of deviation from linearity was not statistically significant (p=0.67). Diabetic women had more than twice the mortality risk of non-diabetic women.

CONCLUSIONS/INTERPRETATION

This study provides further evidence that chronic mild hyperglycaemia, even in the absence of diagnosed diabetes, is associated with increased risk of mortality. ClinicalTrials.gov ID no.: NCT00000479.

Fructose consumption: potential mechanisms for its effects to increase visceral adiposity and induce dyslipidemia and insulin resistance

PURPOSE OF REVIEW

Based on interim results from an ongoing study, we have reported that consumption of a high-fructose diet, but not a high-glucose diet, promotes the development of three of the pathological characteristics associated with metabolic syndrome: visceral adiposity, dyslipidemia, and insulin resistance. From these results and a review of the current literature, we present two potential sequences of events by which fructose consumption may contribute to metabolic syndrome.

RECENT FINDINGS

The earliest metabolic perturbation resulting from fructose consumption is postprandial hypertriglyceridemia, which may increase visceral adipose deposition. Visceral adiposity contributes to hepatic triglyceride accumulation, novel protein kinase C activation, and hepatic insulin resistance by increasing the portal delivery of free fatty acids to the liver. With insulin resistance, VLDL production is upregulated and this, along with systemic free fatty acids, increase lipid delivery to muscle. It is also possible that fructose initiates hepatic insulin resistance independently of visceral adiposity and free fatty acid delivery. By providing substrate for hepatic lipogenesis, fructose may result in a direct lipid overload that leads to triglyceride accumulation, novel protein kinase C activation, and hepatic insulin resistance.

SUMMARY

Our investigation and future studies of the effects of fructose consumption may help to clarify the sequence of events leading to development of metabolic syndrome.

Prevalence of the metabolic syndrome in San Juan, Puerto Rico

OBJECTIVE

The metabolic syndrome is associated with a high risk of diabetes and cardiovascular disease, and Hispanics in the United States have higher rates than do other ethnic groups. We assessed the prevalence of the metabolic syndrome and its individual components in Puerto Rican adults.

METHODS

We conducted a cross-sectional study that used a probability cluster design to select a sample of households of the San Juan metropolitan area from 2005 through 2007. A total of 859 persons aged 21-79 years completed a face-to-face interview, blood pressure and waist circumference measurements, and blood sampling. Our primary outcome measure was metabolic syndrome as defined by the updated NCEP-ATP criteria.

RESULTS

Prevalence of the metabolic syndrome was 43.3%; 45.3% for men and 42.2% for women (P>.05). Prevalence significantly rose with age, from 12.8% among participants aged 21-29 years to 58.2% for participants aged 70-79 years (P<.001). Corresponding increases in the prevalence of the metabolic syndrome in both men and women were also observed; the prevalence peaked in men aged 50-59 years (62.6%) and in women aged 70-79 years (65.2%). Elevated glucose (49.8%) and abdominal obesity (49.0%) were the most common components of the metabolic syndrome, followed by elevated blood pressure (46.1%), reduced high-density lipoprotein cholesterol (46.0%), and elevated triglycerides (31.3%). Substantial variations were found between men and women in the prevalence of individual components.

CONCLUSIONS

Puerto Ricans have a high prevalence of the metabolic syndrome. This health disparity has implications for diabetes and cardiovascular prevention programs.

Menstrual health and the metabolic syndrome in adolescents

The metabolic syndrome, a constellation of interrelated risk factors for cardiovascular disease and type 2 diabetes mellitus, has become a major public health concern against the backdrop of increasing rates of obesity. Insulin resistance plays a pivotal role as the underlying pathophysiological linchpin of the various components of the syndrome. The metabolic syndrome is well recognized in adults, and there is convincing evidence that it starts in childhood, with progressive clustering of the various components over time and tracking through adulthood. Adult women and adolescents with polycystic ovary syndrome (PCOS) have higher prevalence rates of the metabolic syndrome compared with the general population. Several anthropometric (obesity, particularly abdominal obesity), metabolic (insulin resistance/hyperinsulinemia, dyslipidemia) and hormonal (low IGFBP1, IGFBP2 and low sex hormone binding globulin) features of adolescents with PCOS are also features of the metabolic syndrome. Insulin resistance, believed to be a key pathogenic factor in both PCOS and the metabolic syndrome, may be the thread that links the two conditions. Menstrual health in adolescents could be viewed as yet another component in the evaluation of the metabolic syndrome. Careful assessment of menstrual history and appropriate laboratory work-up could reveal the presence of PCOS in obese at-risk adolescent girls with a family history of the metabolic syndrome.

Being overweight modifies the association between cardiovascular risk factors and microalbuminuria in adolescents

OBJECTIVE

The goal was to determine the association between cardiovascular risk factors and microalbuminuria in a nationally representative sample of adolescents and to determine whether being overweight modifies this association.

METHODS

We analyzed cross-sectional data from the National Health and Nutrition Examination Survey (1999-2004) for 2515 adolescents 12 to 19 years of age. Cardiovascular risk factors included abdominal obesity, impaired fasting glucose, diabetes mellitus, insulin resistance, high triglyceride levels, low high-density lipoprotein cholesterol levels, hypertension, smoking, and the metabolic syndrome. Microalbuminuria was defined as a urinary albumin/creatinine ratio of 30 to 299 mg/g in a random morning sample. Overweight was defined as BMI of > or = 95th percentile, according to the Centers for Disease Control and Prevention 2000 growth charts.

RESULTS

Microalbuminuria was present in 8.9% of adolescents. The prevalence of microalbuminuria was higher among nonoverweight adolescents than among overweight adolescents. The median albumin/creatinine ratio decreased with increasing BMI z scores. The association of microalbuminuria with cardiovascular risk factors differed according to BMI category. Among nonoverweight adolescents, microalbuminuria was not associated with any cardiovascular disease risk factor except for overt diabetes mellitus. Among overweight adolescents, however, microalbuminuria was associated with impaired fasting glucose, insulin resistance, hypertension, and smoking, as well as diabetes mellitus.

CONCLUSION

For the majority of adolescents, microalbuminuria is not associated with cardiovascular risk factors. Among overweight adolescents, however, microalbuminuria is associated with cardiovascular risk factors. The prognostic importance of microalbuminuria in overweight and nonoverweight adolescents with regard to future cardiovascular and renal disease needs to be defined in prospective studies conducted specifically in children.

Five-year incidence of type 2 diabetes mellitus among cardiovascular disease-free Greek adults: findings from the ATTICA study

OBJECTIVE

We evaluated the 5-year incidence of diabetes in an adult population from Greece.

RESEARCH DESIGN AND METHODS

3042 individuals (>18 years), free of cardiovascular disease, participated in the baseline examination (during 2001-2002). Of this sample, 1012 men and 1035 women were found alive at the time of follow-up, while 32 (2.1%) men and 22 (1.4%) women died during this period. The rest were lost to follow-up. Incidence of type 2 diabetes mellitus was evaluated in 1806 participants who did not have diabetes at baseline.

RESULTS

The age-adjusted 5-year incidence of diabetes was 5.5% (men, 5.8%; women, 5.2%). A linear trend was observed between diabetes incidence and age (5.6% increases in incidence per 1-year difference in age, p<0.001). Multiple logistic regression analysis revealed that age (OR per 1 yr=1.04, 95% CI 1.02-1.06), waist (OR per 1 cm=1.02, 95% CI 1.01-1.003), physical activity (OR=0.62, 95% CI 0.35-1.02) and family history of diabetes (OR=2.65, 95% CI 1.58-4.53), as well as fasting glucose levels (OR per 1 mg/dl=1.05, 95% CI 1.03-1.07), were the most significant baseline predictors for diabetes, after adjusting for various potential confounders. Additionally, presence of metabolic syndrome at baseline evaluation 2.95-fold the risk of diabetes (95% CI 1.89-4.61), and showed better classification ability than the model that contained the components of the syndrome (ie, correct classification rate: 94.5% vs. 92.3%).

CONCLUSION

Our findings show that a 5.5% incidence rate of diabetes within a 5-year period, which suggests that the prevalence of this disorder in Greece is rising. Aging, heredity, and metabolic syndrome were the most significant determinants of diabetes.

Patterns of relationships between cardiovascular disease risk factors and neurocognitive function in African Americans

OBJECTIVE

The association between cardiovascular disease (CVD) risk and neurocognitive function has gathered a good deal of attention in the health and social science literature; however, the relationship among several CVD risk factors and neurocognitive function has not been fully explored in an African American sample. The purpose of this study was to examine the pattern of relationships among four CVD risk factors and five measures of higher cortical functions.

METHODS

Data were collected from a sample of 106 African American community-dwelling adults in the metropolitan Washington, DC, area. A nurse collected blood pressure, waist circumference, and a blood sample (to assess triglycerides and high-density lipoprotein (HDL) cholesterol) from study participants. Participants completed the Symbol Digit Modalities Test, Trailmaking B, Stroop Color-word Task, California Verbal Learning Test-II, and Wisconsin Card Sorting Test as assessments of neurocognitive function. Canonical analysis and multiple regression analysis were the major statistical methods utilized to assess relationships between CVD risk factors and neurocognitive function.

RESULTS

The results suggest that 1) attentional processes are associated with diastolic blood pressure levels, 2) verbal learning processes are associated with diastolic blood pressure and triglyceride levels, and 3) the ability to shift cognitive set is associated with HDL cholesterol levels.

CONCLUSION

As cardiovascular health worsens in our society, particularly among ethnic minorities, the neurocognitive consequences must be clearly understood. Future studies should focus on identifying and building awareness of cardiovascular and neurocognitive links through longitudinal research designs and brain imaging technology.

Circulating markers of inflammation and their link to indices of adiposity

BACKGROUND

Adipose tissue produces a number of inflammatory mediators. Circulating concentrations of these inflammatory markers are increasingly used as markers of local or systemic inflammation. This study compares results for 3 inflammatory adipokines measured using 2 techniques, (multiplex and ELISA), and determines the relationships with C-reactive protein (CRP), obesity, and the impact of moderate weight loss.

SUBJECTS AND METHODS

Fasting blood samples were collected at baseline and after a 24-week weight loss intervention. Interleukin 6 (IL-6), tumour necrosis factor alpha(TNF-alpha), and monocyte chemoattractant protein 1 (MCP-1) were measured using a standard ELISA technique or a new multiplex technique. A total of 54 women with complete data were included in this analysis.

RESULTS

Multiplex showed poor correlation with ELISA results, and were not significantly correlated with CRP. Using ELISA data, IL-6 and CRP were significantly correlated with body mass index (BMI) (r = 0.42 and r = 0.55), but MCP-1 and TNF-alpha were not (r = - 0.07 and r = 0.06). Changes in MCP-1, TNF-alpha, and IL-6 were not significantly different between control and weight loss groups. CRP was significantly reduced in weight loss vs. control group (p < 0.05), and change in CRP correlated with change in BMI (r = 0.31).

CONCLUSION

Circulating IL-6 and CRP, but not MCP-1 and TNF-alpha, are significantly associated with indices of adiposity in obese women. This study suggests that circulating IL-6 and CRP, but not MCP-1 and TNF-alpha, are useful markers of obesity-related inflammation.

Efficacy and tolerability of second-generation antipsychotics in children and adolescents with schizophrenia

Early-onset schizophrenia-spectrum (EOSS) disorders (onset of psychotic symptoms before 18 years of age) represent a severe variant associated with significant chronic functional impairment and poor response to antipsychotic treatment. All drugs with proven antipsychotic effects block dopamine D(2) receptors to some degree. The ongoing development of the dopamine and other neurotransmitter receptor systems during childhood and adolescence may affect clinical response and susceptibility to side effects in youth. A literature search was conducted of clinical trials of antipsychotics in children and adolescents with EOSS disorders between 1980 and 2007 from the Medline database, reference lists, and conference proceedings. Trials were limited to double-blind studies of duration of 4 or more weeks that included 15 or more patients. Ten clinical trials were identified. Antipsychotic medications were consistently found to reduce the severity of psychotic symptoms in children and adolescents when compared with placebo. The superiority of clozapine has been now demonstrated relative to haloperidol, standard-dose olanzapine, and "high-dose" olanzapine for EOSS disorders. However, limited comparative data are available regarding whether there are differences among the remaining second-generation antipsychotics (SGAs) in clinical effectiveness. The available data from short-term studies suggest that youth might be more sensitive than adults to developing antipsychotic-related adverse side effects (eg, extrapyramidal side effects, sedation, prolactin elevation, weight gain). In addition, preliminary data suggest that SGA use can lead to the development of diabetes in some youth, a disease which itself carries with it significant morbidity and mortality. Such a substantial risk points to the urgent need to develop therapeutic strategies to prevent and/or mitigate weight gain and diabetes early in the course of treatment in this population.

Blood pressure normalization by fixed perindopril/indapamide combination in hypertensive patients with or without associate metabolic syndrome: results of the OPTIMAX 2 study

The aim of the observational pharmaco-epidemiological study Optimax II was to seek whether the pre-existence of a metabolic syndrome (MS) defined by the NCEP-ATP III criteria impacts blood pressure (BP) control in hypertensive patients receiving a fixed perindopril/indapamide combination therapy. The primary objective of the study was to compare in patients with and without MS the rate of BP control defined as a systolic BP < or = 140 mmHg and a diastolic BP < or = 90 mmHg. Patients were prospectively included and the follow-up lasted 6 months. The study population consisted of 24,069 hypertensive patients (56% men; mean age 62 +/- 11 years; 18% diabetics; mean BP at inclusion 162 +/- 13/93 +/- 9 mmHg). MS was found in 30.4% of the patients (n = 7322): 35.2% women and 20.1% men. Three therapeutic subgroups were constituted: Group A, previously untreated, received the combination therapy as initial treatment; Group B, previously treated but with unsatisfactory results and/or treatment intolerance, had its previous treatment switched to perindopril/indapamide; and Group C, previously treated, with good treatment tolerance but uncontrolled BP, received the study treatment in adjunction to the previous one. The normalization rate was 70.3% in group A, 68.4% in Group B, and 64.1% in Group C (p < 0.0001). The pre-existence of MS did not show any significant influence on these rates since BP lowering was -22.7 +/- 13.7 (SBP) and -12.0 +/- 10.0 mmHg (DBP) in patients without MS and 22.6 +/- 13.3 (SBP) and -12.1 +/- 9.7 (DBP) in those with MS. The results of this study show a significant effect of perindopril/indapamide treatment on systolic BP lowering, whatever the treatment status: initiation, switch, or adjunctive therapy, and independently from the presence or not of MS. This effect may be related to the specific vascular effect of the perindopril/indapamide combination, which has recently demonstrated in the ADVANCE trial its ability to reduce mortality, and cardiovascular and renal complications in diabetic patients.

Metabolic syndrome is associated with self-perceived depression

OBJECTIVE

To study the association between metabolic syndrome (MetS) and self-perceived depression.

DESIGN

A cross-sectional community-based study.

SETTING

Semi-rural community of Lapinlahti in eastern Finland in 2005.

SUBJECTS

A total of 416 subjects in eight adult birth cohorts (55%) with complete Beck Depression Inventory (BDI-21) questionnaire data.

MAIN OUTCOME MEASURES

The values of the 21 BDI items and the BDI-21 total score with a cut-off point of 14/15 were used to study the association between MetS and depression. National Cholesterol Education Programme (NCEP) 2005 criteria were used for MetS classification.

RESULTS

The total BDI-21 score was significantly higher in the subjects with MetS than in the subjects without MetS (p=0.020). Men with MetS were significantly worse off than men without MetS in the BDI-21 items of irritability (p=0.008), work inhibition (p=0.008), fatigability (p=0.037), weight loss (p=0.045), and loss of libido (p=0.014), while women were only so on the item of loss of libido (p=0.007). In a logistic regression analysis using a BDI-21 cut-off point of 14/15 adjusted for age, marital status, vocational education, and working status, significant association was retained between perceived depression and elevated blood glucose among men (OR=1.697) and large waist circumference among women (OR=1.066).

CONCLUSION

Elevated plasma glucose in men and central obesity in women are associated with self-perceived depression. This co-occurrence deserves attention in clinical practice.

Metabolic syndrome and insulin resistance in schizophrenia patients receiving antipsychotics genotyped for the methylenetetrahydrofolate reductase (MTHFR) 677C/T and 1298A/C variants

INTRODUCTION

The metabolic syndrome and insulin resistance represent growing concerns related to atypical antipsychotic (AAP) use as their incidence in the schizophrenia population is two-to-four-fold higher than the general population. Reduced methylenetetrahydrofolate reductase (MTHFR) activity, resulting in aberrant folate metabolism and hyperhomocysteinemia, has been linked to cardiovascular disease and is unstudied in relation to AAP associated metabolic complications.

PURPOSE

To examine the relationship between MTHFR, metabolic syndrome, and insulin resistance in schizophrenia subjects receiving AAPs for >or=12 months.

METHODS

Fifty-eight subjects were included in this cross-sectional analysis and screened for the metabolic syndrome, insulin resistance and MTHFR 677C/T and 1298A/C genotype.

RESULTS

Overall, 23 subjects (40%) met metabolic syndrome criteria. There were no differences in age, gender, race, or AAP exposure between genotype groups. For the 677 T allele carriers, 53% met metabolic syndrome criteria, compared to 23% in the CC genotype group, giving an OR=3.7, (95% CI=1.24-12.66, p=0.02). Thus, for T allele subjects, the risk was almost four times greater, despite similar antipsychotic exposure. Both waist circumference and MTHFR genotype significantly predicted insulin resistance (F=8.35, df=5, 51, p<0.0001), with these two terms interacting (F=8.6, df=2, p=0.0006) suggesting that TT subjects are at greater risk for insulin resistance with increasing central adiposity, which is independent of age, gender, BMI, or metabolic syndrome diagnosis.

CONCLUSION

Results should be taken cautiously due to the small sample size, but suggest the MTHFR 677C/T variant may predispose patients to AAP metabolic complications.

Orlistat in the prevention of diabetes in the obese patient

There has been an increase in the concern about preventing type 2 diabetes mellitus (T2DM), a disease with great and increasing prevalence. The prevalence of obesity, physical inactivity, Western processed diet, important risk factors for the development of T2DM, are also rising. Free fatty acids are increased in obesity and reduce insulin clearance and increase hepatic glucose production. Implementation of a healthy lifestyle has been show to slow the progression of impaired glucose tolerance to T2DM. Orlistat is an inhibitor of lipase activity, with proved efficacy in body weight reduction and long-term management of obesity and more favorable effects on carbohydrate metabolism and it was prospectively shown in XENDOS study that orlistat promoted long-term weight loss and prevented T2DM onset in obese individuals with normal and impaired glucose tolerance at baseline over four years. This benefit could be associated to the weight loss itself, to the limited absorption of lipids and reduction of plasma free fatty acids, to increased production of incretins or to modulation of secretion of cytokines by adipocytes, all effects secondary to orlistat treatment. A proposed strategy is to identify subjects at highest risk to receive a drug intervention, using lifestyle interventions alone at the community level.

Vascular risk factors, cognitive decline, and dementia

Dementia is one of the most important neurological disorders in the elderly. Aging is associated with a large increase in the prevalence and incidence of degenerative (Alzheimer's disease) and vascular dementia, leading to a devastating loss of autonomy. In view of the increasing longevity of populations worldwide, prevention of dementia has turned into a major public health challenge. In the past decade, several vascular risk factors have been found to be associated with vascular dementia but also Alzheimer's disease. Some longitudinal studies, have found significant associations between hypertension, diabetus mellitus, and metabolic syndrome, assessed at middle age, and dementia. Studies assessing the link between hypercholesterolemia, atrial fibrillation, smoking, and dementia have given more conflicting results. Furthermore, some studies have highlighted the possible protective effect of antihypertensive therapy on cognition and some trials are evaluating the effects of statins and treatments for insulin resistance. Vascular risk factors and their treatments are a promising avenue of research for prevention of dementia, and further long-term, placebo-controlled, randomized studies, need to be performed.

Effects of short-term very low-calorie diet on intramyocellular lipid and insulin sensitivity in nondiabetic and type 2 diabetic subjects

The study aimed to analyze the effects of a short-term very low-calorie diet (VLCD) on intramyocellular lipid (IMCL), total body fat, and insulin sensitivity in a group of obese nondiabetic and type 2 diabetic subjects. Seven untreated type 2 diabetic and 5 obese nondiabetic individuals were studied before and after a 6-day VLCD using proton magnetic resonance spectroscopy to quantify IMCL, dual-energy x-ray absorptiometry to assess body fat, and hyperinsulinemic-euglycemic clamps to measure peripheral insulin sensitivity. In both groups, decrements in total body fat mass and body mass index were small but statistically significant. In contrast, the diet resulted in a pronounced reduction in IMCL compared with baseline values in nondiabetic subjects (56% decrease) and type 2 diabetic subjects (40% decrease) (P < .05), and this was accompanied by an overall 9.3% increase in maximally stimulated glucose disposal rate (P < .01). Intramyocellular lipid was significantly correlated with insulin sensitivity (r = -0.69, P < .01) and waist circumference (r = 0.72 and 0.83, baseline and postdiet, respectively; both P < .01), but neither IMCL nor insulin sensitivity was related to measures of general adiposity such as body mass index, percentage of body fat, or total body fat (P = not significant). In conclusion, short-term VLCD is accompanied by small decrements in general adiposity, marked decrease in IMCL, and an increase in insulin sensitivity in nondiabetic and type 2 diabetic subjects. Therefore, rapid amelioration of insulin resistance by VLCD can be partially explained by loss of IMCL both in nondiabetic and type 2 diabetic subjects in the absence of substantial changes in total body fat. These observations are consistent with the idea that insulin resistance is more directly related to IMCL rather than to body fat per se.

Prevalence of obesity, hyperlipemia and insulin resistance in children with suprasellar brain tumors

Weight gain is a common sequela of suprasellar tumors, referred to as hypothalamic obesity. We undertook an evaluation of obesity and metabolic aberrations among patients treated at our institute. During the 12 mo from Apr. 2005, 23 patients (10 males and 13 females) with remitted suprasellar tumors attended our clinic: 10 patients with craniopharyngioma, 7 with germinoma, 4 with optic nerve glioma and others. Of these, 12 patients (52%) were found to have obesity on the basis of percent overweight and/or percent body fat. Elevated cholesterol and/or triglyceride (TG) was found in 9 patients (39%), and insulin resistance was suspected in 7 patients (30%). Three patients exhibited strikingly elevated postprandial TG levels. All 6 patients with the growth without GH phenomenon had at least one metabolic aberration. In conclusion, the prevalence of hypothalamic obesity was nearly half in our series, and hyperlipemia and insulin resistance were also frequently found. The increased risk for metabolic aberration in growth without GH patients was suggested.

A randomized controlled trial

BACKGROUND

Intensive lifestyle intervention significantly reduces the progression to diabetes in high-risk individuals.

OBJECTIVE

It is not known whether a program of moderate intervention might effectively reduce metabolic abnormalities in the general population.

DESIGN

Two-arm randomized controlled 1-year trial.

PATIENTS

Three hundred and thirty-five patients participated from a dysmetabolic population-based cohort of 375 adults aged 45-64 years in northwestern Italy.

MEASUREMENTS

We compared the effectiveness of a general recommendation-based program of lifestyle intervention carried out by trained professionals versus standard unstructured information given by family physicians at reducing the prevalence of multiple metabolic and inflammatory abnormalities.

RESULTS

At baseline, clinical/anthropometric/laboratory and lifestyle characteristics of the intervention (n = 169) and control (n = 166) groups were not significantly different. The former significantly reduced total/saturated fat intake and increased polyunsaturated fat/fiber intake and exercise level compared to the controls. Weight, waist circumference, high-sensitivity C-reactive protein, and most of the metabolic syndrome components decreased in the intervention group and increased in the controls after 12 months. Lifestyle intervention significantly reduced metabolic syndrome (odds ratio [OR] = 0.28; 95% CI 0.18-0.44), with a 31% (21-41) absolute risk reduction, corresponding to 3.2 (2-5) patients needing to be treated to prevent 1 case after 12 months. The intervention significantly reduced the prevalence of central obesity (OR = 0.33; 0.20-0.56), and hypertriglyceridemia (OR = 0.48; 0.31-0.75) and the incidence of diabetes (OR = 0.23; 0.06-0.85).

CONCLUSION

A lifestyle intervention based on general recommendations was effective in reducing multiple metabolic/inflammatory abnormalities. The usual care by family physicians was ineffective at modifying progressive metabolic deterioration in high-risk individuals.

Brothers of women with polycystic ovary syndrome are characterised by impaired glucose tolerance, reduced insulin sensitivity and related metabolic defects

AIMS/HYPOTHESIS

Since it has been shown that polycystic ovary syndrome (PCOS) is highly inherited and characterised by insulin resistance, we hypothesised that male siblings of PCOS women would also be insulin resistant. Thus, our aim was to assess insulin sensitivity and metabolic parameters in brothers of women with PCOS and male control individuals.

METHODS

Seventeen brothers of PCOS women and 28 male control volunteers were assessed with 75 g OGTTs and euglycaemic-hyperinsulinaemic clamps. PCOS index women were identified using criteria developed at the 1990 National Institutes of Health conference.

RESULTS

Brothers and control individuals were similar in terms of BMI, waist circumference, percentage body fat and BP. However, brothers had increased triacylglycerol (p = 0.02), plasminogen activator inhibitor-1 (PAI-1; p = 0.02), factor VIII (p = 0.02), 2 h glucose (p < 0.001), AUC(glucose) (p < 0.001) and AUC(insulin) (p < 0.001). Insulin sensitivity was reduced by 38% in brothers (p < 0.001), and this was primarily due to a 65% decrease in insulin-stimulated non-oxidative carbohydrate metabolism (p < 0.001). These differences remained significant after adjustment for age and BMI, except for triacylglycerol, PAI-1 and fasting glucose. The main findings also persisted after excluding individuals with impaired glucose tolerance or diabetic siblings. Significant interactions with BMI status were found for sex hormone-binding globulin, androstenedione, PAI-1 and AUC(insulin), which were significantly altered only in obese brothers (vs control individuals).

CONCLUSIONS/INTERPRETATION

Brothers of PCOS women are characterised by decreased insulin sensitivity and glucose tolerance, as well as hypercoagulability, independently of obesity. Therefore, brothers of PCOS women may have inherited the insulin resistance and metabolic syndrome typical of PCOS.

Association between homocysteinemia and metabolic syndrome in patients with cardiovascular disease

BACKGROUND

This is an observational study undertaken in aim to evaluate the association between metabolic syndrome (MS) and high homocysteinemia (HHcy) in relation with cardiovascular disease (CVD).

METHODS

The study involved 126 subjects with angiographically documented CVD and 65 healthy subjects. MS has been diagnosed according to the ATP III criteria and plasma homocysteine concentration has been evaluated.

RESULTS

In patients with CVD the prevalence of MS and HHcy is 17.4% and 25.4% respectively; MS coexists with HHcy in 67.2% of patients; analogous results can be observed among men and women. HHcy and MS are associated with CVD (OR 2.53, 95% CI 1.95-12.43 and OR 5.74, 95% CI 2.67-12.34 respectively) but the presence of the two conditions gives rise to a stronger increase in CVD risk (OR 13.11, 95% CI 5.27-32.06).

CONCLUSIONS

Our data suggest that HHcy and MS could work together in increasing CVD risk.

Gestational diabetes and the incidence of diabetes in the 5 years following the index pregnancy in South Indian women

This study was carried out to examine the incidence of diabetes and the factors associated with this in a cohort of South Indian women 5 years after they were examined for gestational diabetes (GDM). Women (N=630) whose GDM status was determined (Carpenter-Coustan criteria; GDM: N=41) delivered live babies without major anomalies at the Holdsworth Memorial Hospital, Mysore. Of these, 526 women (GDM: N=35) available for follow-up after 5 years underwent a 2-h oral glucose tolerance test and detailed anthropometry. Diabetes was determined using WHO criteria, and Metabolic Syndrome using IDF criteria recommended for south Asian women. The incidence of diabetes (37% versus 2%) and Metabolic Syndrome (60% versus 26%) was considerably higher in women with previous GDM compared to non-GDM women. GDM women who developed diabetes had lower gestational insulin area-under-the-curve (P=0.05). They had larger waist-to-hip ratio, skinfolds, body mass index, and lower 30-min insulin increment at follow-up than other GDM women. In all, history of diabetes in first-degree relatives was independently associated with higher incidence of diabetes (P<0.001). Our findings suggest high diabetes and cardiovascular risks in women with previous GDM. Follow-up of these women after delivery would provide opportunities to modify adverse lifestyle factors.