Statin therapy for primary prevention in women: What is the role for coronary artery calcium?

By current guidelines, statin treatment decisions depend on multiple risk factor algorithms (e.g., pooled cohort equations [PCEs]). By available PCEs most older middle-aged women are statin eligible. But several studies cast doubt on reliability of available PCEs for ASCVD risk assessment. An alternative method for risk assessment is a coronary artery calcium (CAC) score. Many older women have zero CAC, which equates to low risk for ASCVD; these women can delay statin therapy for several years before re-scanning. When CAC is 1-99 Agatston units, risk is only borderline high and statin delay also is an option until re-scanning. When CAC is > 100 Agatston units, risk is high enough to warrant a statin. In most women, CAC is the best guide to treatment decisions. In high-risk women (e.g., diabetes and severe hypercholesterolemia), generally are indicated, but CAC can assist in risk assessment, but other risk factors also can aid in treatment decisions.

Utility of metabolic syndrome as a risk enhancing factor in decision of statin use.

BACKGROUND: Statins effectively reduce risk for atherosclerotic cardiovascular disease (ASCVD) when 10-year risk is ≥ 7.5%. In many patients at intermediate risk (7.5-<20% risk), there is uncertainty about reliability of risk assessment by current pooled cohort equations (PCE). A decision to initiate statin therapy is favored by several risk enhancing factors not employed in PCEs. OBJECTIVE: This study examines the scope of the metabolic syndrome, a risk enhancing factor, and its principal sequala, diabetes, in 26,796 US adults age 40-75 years from the NHANES survey data, 1999-2016. METHODS: The prevalence of metabolic syndrome without diabetes (MetS+) and of diabetes (DM+) were determined for 10-year risk categories estimated to be low (<7.5%), intermediate (7.5% -< 20%) and high (≥20%). Data were weighted to account for complex study design. RESULTS: 90.4% of the population was free of ASCVD. In subjects projected to be at low risk by PCEs, MetS+ was present in 15.0% and 17.6% of women and men, respectively. MetS + increased to 30.6% of women and 29.6% of men at intermediate risk, and to 21.5% of women and 32.2% of men at high risk. In addition, DM+ was present in 6.1%/5.3% (F/M) of low risk individuals, 20.1%/14.8% (F/M) of intermediate risk subjects, and 44.3%/39.4% (F/M) of high-risk persons. Prevalence of both MetS+ and DM + rose progressively with age in women and men. CONCLUSIONS: MetS+ and DM + are common multiplex risk factors that predispose to higher lifetime risk and support statin therapy in patients at intermediate and high risk.

Chronic kidney disease and statin eligibility.

BACKGROUND: Chronic kidney disease (CKD) is a risk factor for atherosclerotic cardiovascular disease (ASCVD). American cardiovascular societies consider CKD a risk-enhancing factor that supports statin therapy in intermediate-risk patients aged 40-75 years. In contrast, European cardiovascular societies recommend statins for all middle-aged adults with CKD. The Kidney Disease: Improving Global Outcomes lipid management guideline for CKD recommends statin therapy for all patients with CKD >50 years. Clinical implications for these differences have not been examined. OBJECTIVE: This study examines CKD prevalence and statin eligibility in non-ASCVD adults, representative of the US population, at 3 levels of 10-year risk of ASCVD estimated by pooled cohort equations. METHODS: National Health and Nutrition Examination Surveys 1999-2016 weighted data were evaluated for CKD defined as estimated glomerular filtration rate < 60 mL/min/1.73 m2. Overall prevalence of low, intermediate, and high 10-year risk for ASCVD was determined. RESULTS: A total of 92.5% of all participants had estimated glomerular filtration rate ≥ 60 mL/min/1.73 m2; 7.5% (confidence interval 6.9%, 8.1%) had CKD. Among participants with CKD, 46.3% had 10-year risk for ASCVD <7.5% (low risk); 31.7% had intermediate risk (7.5-< 20%), and 22.0% had high risk (≥20%). In participants with CKD, 62.5% were women. A total of 19.6% of all participants with CKD had diabetes. A total of 46.3% of participants with CKD at intermediate or high risk reported taking cholesterol-lowering drugs. CONCLUSION: A total of 46.3% of patients with CKD aged 40-75 years had 10-year risk <7.5% (low risk) and hence were statin eligible by European and Kidney Disease: Improving Global Outcomes (>50 years) guidelines. US cardiovascular guidelines limit statin eligibility to intermediate- and high-risk CKD. Statin eligibility in lower-risk patients may be best determined by measuring coronary artery calcium.

Coronary and peripheral artery plaques: do differences in plaque characteristics translate to differences in lipid management?

Optimal medical management of patients with peripheral arterial disease (PAD) includes statin therapy, which has been shown to decrease the risk of major cardiovascular events. However, the relationship between low-density lipoprotein (LDL) lowering, PAD progression and limb outcomes remains controversial. Although prevention of coronary and cerebrovascular events is a priority, limb outcomes are still important determinants of quality of life and healthcare spending. This review will highlight differences between coronary artery disease (CAD) and PAD, and in particular, the more prevalent role of lipids and LDL cholesterol in CAD versus calcification in PAD. This difference may contribute to the differential impact of LDL cholesterol levels on coronary events and outcomes versus limb outcomes. Beyond LDL lowering, immune modulators have emerged as another agent to treat atherosclerosis in CAD, however similar data in PAD are lacking. Small studies have suggested that other lipids besides LDL cholesterol, such as triglycerides or small dense LDL, may have a greater impact on limb outcomes in patients with PAD. Although statin therapy is central in the management of patients with PAD, current understanding of the distinctions between PAD and CAD suggest that there may be other non-LDL targets for risk reduction that require further study.

Temporal decline in non-high-density lipoprotein cholesterol in subjects with diabetes mellitus without atherosclerotic cardiovascular disease.

BACKGROUND: Non-high-density lipoprotein cholesterol (non-HDL-C) includes atherogenic cholesterol and low-density lipoproteins (LDL) and triglyceride-rich lipoproteins. Patients with diabetes frequently have elevations in non-HDL-C. OBJECTIVE: This study examines temporal trends in the levels of non-HDL-C in free-living subjects with diabetes but a negative history of atherosclerotic cardiovascular disease. METHODS: National Health and Nutrition Examination Surveys conducted between 1999 and 2016 had data from 3,219 adults (aged 40-75 years) with diabetes. Temporal trends in changes in the distribution of total cholesterol, non-HDL-C, LDL cholesterol (LDL-C), and HDL-C were evaluated. Data were weighted to account for complex survey design. RESULTS: Significant decreases were observed in non-HDL-C (20.1%; P < .0001) and total cholesterol (16.1%; P < .0001) levels between 1999 and 2016. No significant changes were noted in HDL-C levels. LDL-C was reduced by 29.6% in a subset of subjects. The reduction in non-HDL-C and LDL-C occurred simultaneously, with an increase of 4.4% of subjects per year taking cholesterol-lowering drugs and statins. In contrast, the fraction of subjects taking antihypertensives or hypoglycemia agents rose at a rate of 2.2% per year. There was also a significant trend for increases in weight gain (P ≤ .013). CONCLUSIONS: In subjects with diabetes, non-HDL-C levels have declined over time in parallel with reported increases in cholesterol-lowering drugs. Nonetheless, treatment targets for lipids in subjects with diabetes lag behind current recommendations. Reported intakes for antihypertensive agents and hypoglycemia agents were relatively high throughout the period of study, with little change over time. However, there was a trend for weight increase in diabetic subjects, which may offset some of the benefits of pharmacotherapy.

Traditional signs and symptoms commonly attributed to hypogonadism do not correlate with testosterone levels: the Cooper Center Longitudinal Study Experience.

Evidence suggests that substantial testosterone therapy is occurring without checking levels of testosterone, presumably based on the presence of symptoms alone. We sought to explore the relationship between total testosterone level and non-specific symptoms, metabolic abnormalities, and sexual dysfunction associated with hypogonadism. This cross-sectional study included 2994 generally healthy men aged 50-79 years examined at a preventive medicine clinic in Dallas, TX from January 2012 to March 2016. Symptoms of hypogonadism were assessed. Screening morning total testosterone levels were measured and categorized into low (<250 ng/dL), low normal (250-399 ng/dL), and normal (≥400 ng/dL). Multiple logistic regression models were used to test the associations between total testosterone and signs and symptoms of hypogonadism. When considering symptoms and signs of hypogonadism, only decreased libido (OR 1.31, 95% CI 1.00 to 1.70), fasting glucose ≥100 mg/dL (OR 1.47, CI 1.15 to 1.88), and hemoglobin A1c over 6% (OR 1.47, 95% CI 1.06 to 2.03) were associated with increased odds of low testosterone after adjustment for age, body mass index, and cardiorespiratory fitness. Testosterone levels were not associated with fatigue, depression, or erectile dysfunction in our study (p>0.6). In this preventive medicine cohort, symptoms commonly attributed to testosterone deficiency were not associated with low total testosterone levels.

Current trends in non-HDL cholesterol and LDL cholesterol levels in adults with atherosclerotic cardiovascular disease.

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) are targets for prevention of atherosclerotic cardiovascular disease (ASCVD). The American Heart Association and American College of Cardiology recently modified recommendations for clinical management of cholesterol in secondary and primary prevention. Accordingly, the present article examines the need for cholesterol-lowering drugs in the U.S. population with ASCVD. OBJECTIVE: This study examines trends in non-HDL-C and LDL-C levels in a free living population of ASCVD subjects between 1999 and 2016. METHODS: National Health and Nutrition Examination Surveys database included 4920 adults with ASCVD aged 40 to 85 years. Complete data were available for 4226. Trend analysis of changes in lipids is shown in box plots. RESULTS: Mean age was 67 years with 57% males. Over 17 years, LDL-C decreased significantly by 24% and non-HDL-C by 21%. Over the period of study, reported intake of cholesterol-lowering drugs rose from 37% in 1999-2000 to 69% in 2015 to 2016. Over this same period, serum triglycerides decreased by 29% (P < .001) and HDL-C rose by 6%. CONCLUSIONS: The changes in LDL-C and non-HDL-C in patients with ASCVD over a 17-year period probably are related to increased treatment with statins. However, the changes are too small to be explained by widespread use of high-intensity statins, which is the current recommendation for patients with ASCVD. These findings pose a challenge for professional education to support implementation of current guidelines for cholesterol-lowering therapies.

Metabolic syndrome is a sequela of radiation exposure in hypothalamic obesity among survivors of childhood brain tumors.

Survivors of childhood brain tumors may be at risk for early onset of metabolic syndrome, possibly secondary to surgery and/or radiation exposure. This study examines effects of radiation exposure to hypothalamus-pituitary-adrenal axis (HPA) on metabolic risk among survivors of childhood brain tumors. One hundred forty-two met inclusion criteria; 60 had tumor surgery plus radiation exposure (>1 Gray (Gy)) to HPA. The second subgroup of 82 subjects had surgery only and were not exposed to radiation. Both subgroups had survived for approximately 5 years at the time of study. All had clinical evaluation, vital signs, anthropometry, measurement of body composition by dual X-ray absorptiometry and fasting laboratory assays (metabolic panel, insulin, C-peptide, insulin-like growth factor-1, leptin and adiponectin). Body composition data for both subgroups was compared with the National Health and Nutrition Survey (NHANES) subgroup of similar age, gender and body mass index. Cranial surgery was associated with obesity of similar severity in both subgroups. However, survivors exposed to radiation to the HPA also had increased visceral fat mass and high prevalence of growth hormone deficiency and metabolic syndrome. Fat mass alone did not explain the prevalence of the metabolic syndrome in radiation exposure subgroup. Other factors such as growth hormone deficiency may have contributed to metabolic risk. We conclude that prevalence of metabolic syndrome among subjects exposed to hypothalamic radiation was higher than expected from hypothalamic obesity alone. Radiation exposure may exert untoward endocrinopathies due to HPA exposure that worsens metabolic risk. Early screening for metabolic syndrome in this population is indicated.

Metabolic Concomitants of Obese and Nonobese Women With Features of Polycystic Ovarian Syndrome.

CONTEXT: Polycystic ovarian syndrome (PCOS) is often associated with obesity and diabetes. OBJECTIVE: The present study measured body fat distribution and metabolic risk factors in women with features of PCOS. DESIGN: Cross-sectional, multiethnic study of cardiovascular risks. SETTING: General community. STUDY PARTICIPANTS: 145 PCOS and 344 non-PCOS women. EXPOSURE MEASURES: Body composition by dual x-ray absorptiometry; abdominal fat masses measured by magnetic resonance imaging and hepatic triglyceride by magnetic resonance spectroscopy. OUTCOMES MEASURES: Body composition, liver fat content, homeostatic model assessment for insulin resistance (HOMA-IR), revised, and metabolic syndrome components. RESULTS: PCOS women had a higher free androgen index compared with the non-PCOS women. Nonobese PCOS and non-PCOS women had a similar body fat content and distribution, HOMA-IR, and hepatic triglyceride content. Obese PCOS women had a similar total body fat percentage compared with their non-PCOS counterparts (41.4% and 41.4% respectively). Both obese groups had similar intraperitoneal fat (1.4% of total body mass in PCOS vs 1.4% in non-PCOS). However, obese PCOS women had a greater ratio of truncal/lower body fat (1.42 vs 1.27; P < 0.016). They also had greater insulin resistance (HOMA-IR: PCOS, 2.24% vs non-PCOS, 1.91%; P < 0.016), higher liver triglyceride content (6.96% in PCOS vs 4.44% in non-PCOS; P < 0.016), and a greater incidence of hypertension (33% vs 24%; P < 0.05). No differences were observed in other metabolic risk factors. CONCLUSIONS: Both obese and nonobese women with PCOS features had a greater free androgen index compared with non-PCOS women, but neither had greater intraperitoneal fat or abnormal lipid levels. Obese, but not nonobese, women with PCOS had a greater truncal/lower extremity fat ratio, HOMA-IR, and liver triglyceride content.

Association of triglyceride-to-high density lipoprotein cholesterol ratio to cardiorespiratory fitness in men.

BACKGROUND: Both triglyceride-to-high density lipoprotein cholesterol (TG/HDL-C) and cardiorespiratory fitness (CRF) impart risk for all-cause morbidity and mortality independently of conventional risk factors. OBJECTIVE: To determine prevalence and/or incidence of high TG/HDL-C ratio in men with low CRF. METHODS: Clinical characteristics and CRF were used to determine prevalence of a TG/HDL-C ratio ≥ 3.5 (high ratio) in 13,954 men of the Cooper Center Longitudinal Study. High-ratio conversion was determined in 10,424 men with normal baseline TG/HDL-C ratio. Hazard ratio (HR) of incident high TG/HDL-C was adjusted for age and waist girth. RESULTS: Men with low CRF had the highest prevalence of a high TG/HDL-C ratio. In the population with normal TG/HDL-C, age-adjusted HR of incident high TG/HDL-C ratio was 2.77 times higher in men with lowest CRF than in those with highest CRF. Incidence of conversion of normal to high ratio was 5.5% per year in low CRF population, compared with 1.7% in high CRF subjects. Incidence HR was independent of waist girth. Men who converted from normal to high TG/HDL-C ratio during the follow-up period had increased number of metabolic risk factors and a higher prevalence of metabolic syndrome. Men who did not convert to a high TG/HDL-C ratio retained a low prevalence of metabolic syndrome risk factors. CONCLUSION: A high TG/HDL-C ratio is common in men with low CRF. Metabolic syndrome also is common among those with a high ratio.

Fatty acid oxidation in normotriglyceridemic men.

BACKGROUND: Moderate hypertriglyceridemia is frequently associated with central obesity, insulin resistance, and atherogenic dyslipidemia. We showed previously that moderately obese men with hypertriglyceridemia have reduced fatty acid oxidation postabsorptively and postprandially. In the present study, we examined the oxidation of fatty acids in normotriglyceridemic men. OBJECTIVE: The study objective was to determine the relation between plasma triglyceride levels and fatty acid oxidation in normotriglyceridemic men. STUDY DESIGN: Twenty-four healthy, nonobese White and African American men participated in a cross-sectional metabolic study for evaluation of fatty acid oxidation. Men were healthy, and none took hypolipidemic or hypoglycemic agents. They ingested 200 mg of fat/hour/kg of body weight over a 10-hour period. Plasma levels of triglyceride, nonesterified fatty acids, 3-ß-hydroxybutyrate, insulin, and glucagon were measured postabsorptively and postprandially. Chylomicron-triglyceride halflife was also calculated. RESULTS: Nonobese White and African-American men had similar anthropometry, levels of plasma triglyceride, lipoprotein cholesterol, nonesterified fatty acids, 3-ß-hydroxybutyrate, insulin, and glucagon postabsorptively and postprandially. For the group as a whole, there was a positive and significant correlation between plasma fatty acids and 3-ß-hydroxybutyrate and an inverse association between plasma triglyceride levels and 3-ß-hydroxybutyrate at baseline. All subjects had increased levels of metabolites of interest postprandially. However, there were no significant changes in plasma insulin, glucagon, or the ratio of insulin to glucagon. The postprandial levels of 3-ß-hydroxybutyrate correlated positively with nonesterified fatty acids and inversely with the half-life of chylomicron triglyceride. CONCLUSION: Normotriglyceridemia is strongly associated with oxidation of fatty acids by the liver suggesting the possibility that the fatty acid oxidation pathway is a potential target of intervention to prevent hypertriglyceridemia and concomitant fatty liver.

Triglyceride-to-high-density-lipoprotein-cholesterol ratio is an index of heart disease mortality and of incidence of type 2 diabetes mellitus in men.

BACKGROUND: High triglyceride (TG) and low high-density lipoprotein cholesterol (HDL-C) impart risk for heart disease. This study examines the relationships of TG/HDL-C ratio to mortality from all causes, coronary heart disease (CHD), or cardiovascular disease (CVD). SUBJECTS AND METHODS: Survival analysis was done in 39,447 men grouped by TG/HDL-C ratio cut point of 3.5 and for metabolic syndrome. National Death Index International Classification of Diseases (ICD-9 and ICD-10) codes were used for CVD and CHD deaths occurring from 1970 to 2008. Incidence of type 2 diabetes mellitus (DM) according to ratio was estimated in 22,215 men. Triglyceride/HDL-C ratio and cross-product of TG and fasting blood glucose (TyG index) were used in analysis. RESULTS: Men were followed up for 581,194 person-years. Triglyceride/HDL-C ratio predicted CHD, CVD, and all-cause mortality after adjustment for established risk factors and non-HDL-C. Mortality rates were higher in individuals with a high ratio than in those with a low ratio. Fifty-five percent of men had metabolic syndrome that was also predictive of CHD, CVD, and all-cause mortality. Annual incidence of DM was 2 times higher in men with high TG/HDL-C ratio than in those with a low ratio. Individuals with high TG/HDL-C ratio had a higher incidence of DM than those with a low ratio. The TyG index was not equally predictive of causes of mortality to TG/HDL-C, but both were equally predictive of diabetes incidence. CONCLUSIONS: Triglyceride/HDL-C ratio predicts CHD and CVD mortality as well as or better than do metabolic syndrome in men. Also, a high ratio predisposes to DM. The TyG index does not predict CHD, CVD, or all-cause mortality equally well, but like TG/HDL-C ratio, it predicts DM incidence.

Ethnic and gender susceptibility to metabolic risk.

BACKGROUND: Aggregation of metabolic risk factors-i.e., elevated plasma triglyceride (TG), reduced high-density lipoprotein cholesterol (HDL-C), elevated blood pressure, and raised plasma glucose-convey increased risk for atherosclerotic cardiovascular disease and type 2 diabetes. METHODS: This study was carried out to determine the association of waist girth, ethnicity, and gender with susceptibility for metabolic risk. Included were 1671 adult women (50.7% black) and 1339 men (46.5% black) enrolled in the Dallas Heart Study. Subjects were stratified into three categories by waist girth-low, intermediate, and high, corresponding to BMI ranges of <25 kg/m(2), 25-29.9 kg/m(2), and ≥30 kg/m(2). RESULTS: Risk factor prevalence rose progressively through each waist-girth category. However, even among those with high waist-girth, prevalence of three or more risk factors was less than 50%. Several differences among the ethnic groups were noted; for example, Hispanic men had a higher prevalence of elevated TG compared to whites; black men, on the other hand, had a lower frequency of high TG. There were also fewer black men with low HDL-C than in the other groups. Black and Hispanic men had a higher prevalence of elevated glucose and updated homeostasis model assessment of insulin resistance (HOMA2-IR) than whites. More black men had elevated blood pressure than other groups. These differences were less pronounced among ethnic groups of women. CONCLUSION: Although ethnic and gender differences in risk factor prevalence may exist, it is notable that the majority of subjects, even when obese, did not have elevated risk factors. This finding points to the need to focus largely on subjects with metabolic risk factors when implementing therapeutic interventions.

Waist circumference as measure of abdominal fat compartments.

This study examines intercorrelations among waist circumference (WC), intraperitoneal fat (IPF), and subcutaneous abdominal fat (SAF) in ethnically diverse Dallas Heart Study consisting of 1538 women and 1212 men (50% Black). Correlations between fat depots and triglyceride or HOMA2-IR, biomarkers of metabolic syndrome, are also reported. Total abdominal fat (TAF), ASF, and IPF masses were measured by magnetic resonance imaging. The highest correlations with WC according to ethnicity and gender were noted for TAF (R (2) = 0.81 - 0.88) with progressively lower correlations with ASF (0.65-0.82) and IPF (0.29-0.85). The percentage of IPF relative to TAF was not significantly correlated with WC. For all WC categories, higher IPF/ASF ratios were associated with higher triglyceride levels. In contrast, differences in ratios had little or no association with HOMA2-IR. However, when all data were pooled, IPF was positively correlated with both triglyceride (r = 0.358 (men) and 0.363 (women)) and HOMA2-IR (r = 0.480 (men) and 0.517 (women)); after adjustment for ASF, IPF was still correlated with triglyceride (r = 0.353 (men) and 0.348 (women)) and HOMA2-IR (r = 0.290 (men) and 0.221 (women)). WC measures TAF reliably, but its association with IPF depends on IPF/ASF ratios that vary by gender and ethnicity.

LDL phenotype in subjects with mild cognitive impairment and Alzheimer's disease.

BACKGROUND: Centenarians with normal cognitive function have a "longevity phenotype" characterized by large low-density lipoproteins (LDL) and high-density lipoproteins (HDL) and low incidence of metabolic syndrome, hypertension, and cognitive impairment. Alzheimer's disease (AD) is associated with a number of cardiovascular risk factors, but it is not known if they have or lack the "longevity phenotype". OBJECTIVE: The study was designed to determine LDL size and body fat content and distribution in subjects with mild cognitive impairment (MCI) and AD. RESULTS: Fifty-eight persons with MCI or AD (cases) and 42 control subjects of similar age had measurement of LDL size and lipoprotein lipids after a 12 h fast and analysis of body composition by dual x-ray absorptiometry. Cases had small LDL size more often than controls (73% versus 66%) associated with significantly higher triglycerides, lower HDL cholesterol, and higher triglyceride/HDL cholesterol ratio (p ≤ 0.02). Cases with large LDL had a better lipoprotein profile than those with small LDL. Cases and controls had similar percent body fat, fat index, and lean mass index. Forty-seven percent of cases and 39% of controls were obese. CONCLUSION: The prevalence of small LDL phenotype in MCI and AD cases contrasts with the "longevity phenotype" reported for centenarians with preserved cognitive function. The small LDL phenotype is an atherogenic lipoprotein profile found in metabolic syndrome, type 2 diabetes, and insulin resistance. It is now also reported in persons with MCI and AD.

Metabolic risk susceptibility in men is partially related to adiponectin/leptin ratio.

BACKGROUND: High adiponectin/leptin ratio may be protective from metabolic risks imparted by high triglyceride, low HDL, and insulin resistance. METHODS: This cross-sectional study examines plasma adipokine levels in 428 adult men who were subgrouped according to low (<6.5 µ g/mL)and high (≥6.5 µ g/mL)adiponectin levels or a low or high ratio of adiponectin/leptin. RESULTS: Men with high adiponectin/leptin ratio had lower plasma triglyceride and higher HDL cholesterol than those with low ratio. Similarly, those with high adiponectin/leptin ratio had lower TG/HDL cholesterol ratio and HOMA2-IR than those with low ratio. In contrast, levels of adiponectin or the ratio of adiponectin/leptin did not associate with systolic blood pressure. But the ratio of adiponectin/leptin decreased progressively with the increase in the number of risk factors for metabolic syndrome. CONCLUSION: Adipokine levels may reflect adipose tissue triglyceride storage capacity and insulin sensitivity. Leptin is an index of fat mass, and adiponectin is a biomarker of triglyceride metabolism and insulin sensitivity. Men with high adiponectin/leptin ratios have better triglyceride profile and insulin sensitivity than men with a low ratio regardless of waist girth.

Fasting glucose, obesity, and metabolic syndrome as predictors of type 2 diabetes: the Cooper Center Longitudinal Study.

BACKGROUND: To determine risk for type 2 diabetes in subjects with fasting glucose levels in the ranges of normoglycemia, mild hyperglycemia, and intermediate hyperglycemia and to assess the effect of obesity and metabolic syndrome on this risk. SUBJECTS AND METHODS: Incidence of type 2 diabetes mellitus was evaluated in 28,209 relatively healthy subjects participating in the Cooper Center Longitudinal Study. They were included in the study if they had more than 1 fasting plasma glucose measurement, anthropometry, and other parameters of interest. Three subgroups were identified: normoglycemic (<5.6 mmol/L), mild hyperglycemia (5.6-6.0 mmol/L), and intermediate hyperglycemia (6.1-7.0 mmol/L). Diabetes incidence was calculated in categories of sex, age, obesity, and metabolic syndrome status. Incident diabetes was assessed at the earliest clinic visit at which the individual exhibited a blood glucose level of more than 7.0 mmol/L or reported a diagnosis of diabetes. RESULTS: Thirty-one percent of men and 15.9% of women had mild hyperglycemia and 11.9% of men and 3.6% of women had intermediate hyperglycemia. Yearly conversion rates to diabetes were low in individuals with normoglycemia and mild hyperglycemia but were strikingly higher in those with intermediate hyperglycemia. In subjects with intermediate hyperglycemia, presence of obesity and/or metabolic syndrome doubled conversion rates to diabetes. CONCLUSIONS: This study showed a marked difference in outcomes in subjects with mild and intermediate hyperglycemia. Moreover, obesity and metabolic syndrome were associated with strikingly elevated risk for diabetes in subjects with intermediate hyperglycemia. Thus intermediate hyperglycemia plus obesity/metabolic syndrome seemingly justifies intensive clinical intervention for prevention of both diabetes and cardiovascular disease.

Influence of upper and lower body adipose tissue on insulin sensitivity in South Asian men.

BACKGROUND: South Asians have a high prevalence of insulin resistance, which predisposes to type 2 diabetes. RATIONALE: In the current study, we examined whether insulin sensitivity in South Asian men and men of European descent (Europids) relates to truncal and lower body fat, number of adipocytes, and cell size distribution. RESULTS: Fifteen South Asian men and 15 Europid young men with comparable body mass indexes completed assessments of insulin sensitivity, body composition analysis by dual-energy x-ray absorptiometry, and measurement of adipocyte cellularity in the subcutaneous abdominal (truncal) and gluteal (lower body) adipose tissue. The South Asians and the Europids had similar total body fat and fat contents in truncal and lower body regions. Compared to the Europids, the South Asians had a greater insulin resistance shown by fasting insulin, area-under-the-curve for postprandial insulin, oral glucose insulin sensitivity, homeostatic model assessment of insulin resistance, ß-cell index, and triglyceride-to-high-density lipoprotein ratio. The South Asians had similar number of adipocytes to the Europids, but the South Asians had significantly higher ratios of small-to-larger adipocytes. The South Asians further had a higher fraction of very large adipocytes. In both South Asians and Europids, truncal fat was positively associated with insulin resistance. In the South Asians but not in the Europids, lower body fat was associated with severity of insulin resistance. CONCLUSIONS: The results suggest first, a higher ratio of small-to-larger adipocytes in the South Asians consistent with a lesser lipid storage capacity of adipose tissue; and second, the positive association of lower body fat with insulin resistance in the South Asians implies that fat in their lower body worsens insulin resistance. This association was not observed in the Europids.

Effect of colesevelam hydrochloride on glycemia and insulin sensitivity in men with the metabolic syndrome.

Colesevelam hydrochloride (colesevelam) lowers low-density lipoprotein (LDL) cholesterol and glycated hemoglobin in patients with type 2 diabetes mellitus. The present study examined the effects of colesevelam treatment in nondiabetic men with metabolic syndrome. Twenty men completed the study, which consisted of two 8-week phases of treatment with colesevelam (3.75 g/day) or placebo and a 6-week washout between study phases. Of the 20 men, 17 took statins throughout. The fasting plasma LDL cholesterol, triglyceride, glucose, and glycated hemoglobin levels were measured in the last 2 weeks of each study phase. Nonesterified fatty acids and 3-hydroxybutyrate, insulin, and glucose were measured hourly for 5 hours during fasting and during an extended glucose tolerance test. The colesevelam treatment reduced LDL cholesterol from 96 ± 28 mg/dl to 78 ± 32 mg/dl (p <0.006) and non-high-density lipoprotein cholesterol by 8.2% (p = 0.07). Triglycerides increased by 17% (p <0.02). The fasting plasma glucose was reduced by 5 mg/dl (p <0.03), and glycated hemoglobin remained unchanged by colesevelam. No significant treatment changes were noted for the 2-hour glucose test or insulin sensitivity. The fasting nonesterified fatty acid level was significantly reduced with treatment but the 3-hydroxybutyrate level was unchanged. Insulin-mediated suppression of nonesterified fatty acids during extended glucose tolerance test was significantly less effective during treatment than during placebo. In conclusion, colesevelam significantly reduced the LDL cholesterol levels, even though the baseline LDL cholesterol level was low owing to statin treatment. The fasting and postprandial blood glucose level but not the glycated hemoglobin level was lowered by colesevelam therapy. The effect on fasting glucose was unrelated to the changes in insulin resistance or fatty acid oxidation. Finally, an increase in triglycerides with colesevelam therapy might have been related to a lesser suppression of nonesterified fatty acids levels in the postprandial state.