The dyslipidemia of diabetes mellitus: giving triglycerides and high-density lipoprotein cholesterol a higher priority?

Pancreatic β-cell apoptosis caused by apolipoprotein C3-rich low-density lipoprotein is attenuated by kansuinine A through oxidative stress inhibition

Dyslipidemia exacerbates pancreatic β-cell apoptosis, heightening the risk of type 2 diabetes (T2DM). Kansuinine A (KA), a diterpene from Euphorbia roots, exhibits antiapoptotic properties, suggestive of its therapeutic potential against T2DM. In this study, we evaluated the protective effects of KA against apolipoprotein C3 (ApoC3)-rich low-density lipoprotein (LDL) (AC3RL)-induced β-cell apoptosis and its underlying mechanism of action. ApoE-/- mice fed a high-fat diet and treated with KA demonstrated improved glucose and insulin tolerance, enhanced antioxidant capacity, and reduced pancreatic β-cell apoptosis. In rat pancreatic β-cells (RIN-m5F) exposed to AC3RL, KA significantly improved cell viability, suppressed oxidative stress, and mitigated apoptosis by downregulating lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) expression and inhibiting the IκB kinase β (IKKβ)/Inhibitor of κB alpha (IκB⍺)/Nuclear Factor kappa B(NF-κB) signaling pathway. Molecular docking and pathway analyses revealed the interactions of KA with key targets involved in oxidative stress and apoptosis. These findings highlight the ability of KA to counteract AC3RL-induced β-cell dysfunction, offering promise as a potential intervention for dyslipidemia-driven diabetes.

The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and its combination with obesity indicators as a predictor of all cause and cardiovascular mortality in non-diabetic individuals

BACKGROUND

The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) represents a novel composite lipid marker for atherosclerosis and cardiovascular disease (CVD). Nevertheless, the correlation between NHHR and mortality in the non-diabetic population remains indistinct.

METHODS

This study included 20,774 non-diabetic individuals from the 1999-2018 National Health and Nutrition Examination Survey (NHANES). We employed a weighted multivariate Cox proportional hazards model and restricted cubic splines to assess the associations between NHHR, its combination with obesity indicators, and all-cause and CVD mortality.

RESULTS

During a mean follow-up period of 62 months, a total of 897 participant deaths were recorded, of which 155 were attributed to cardiovascular causes. The restricted cubic splines revealed a U-shaped association between NHHR and all-cause mortality, while an L-shaped association was observed for CVD mortality. The analysis of threshold efects revealed that the infection points for NHHR and all-cause and CVD mortality were 2.65 and 2.07, respectively. The cubic spline revealed a nonlinear correlation was observed between NHHR-BMI, NHHR-WC and NHHR-WHtR and all-cause and CVD mortality.

CONCLUSION

NHHR and its combination with obesity indicators can be a meaningful predictor of all-cause mortality and CVD mortality in non-diabetic individuals.

Relationship between periodontal status and dyslipidemia in patients with type 2 diabetic nephropathy and chronic periodontitis: A cross-sectional study

OBJECTIVE

The aim of this study was to investigate the association between periodontitis and total serum cholesterol level in patients with type 2 diabetic nephropathy (T2DN).

BACKGROUND

Periodontitis is now recognized as the sixth complication of diabetes and can also affect other complications of diabetes, including nephropathy and coronary artery diseases. Studies have considered dyslipidemia as a risk factor for exacerbation of periodontitis.

METHODS

A total of 119 T2DN patients with chronic periodontitis were included in this observational study. Participants were stratified into the Normal (serum total cholesterol <5.17 mmol/L, n = 89) and the Dyslipidemia groups (serum total cholesterol ≥5.17 mmol/L, n = 30). Participants completed a validated questionnaire that collected information on oral hygiene behaviors and knowledge of oral health and underwent a clinical oral examination. The number of remaining teeth, probing depth (PD), clinical attachment level (CAL), and bleeding index (BI) was recorded. Physical examination and laboratory tests (fasting plasma glucose, serum glycosylated hemoglobin (HbA1c), total cholesterol, high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), triglyceride, and high-sensitivity C-reactive protein levels) were performed.

RESULTS

Means of CAL and BI were significantly higher in the Dyslipidemia group compared with the Normal group. In the Dyslipidemia group, PD and percent of sites with PD ≥4 mm were positively correlated with urinary albumin/creatinine ratios; PD and percent of sites with PD ≥4 and PD ≥5 mm were positively correlated with HbA1c level; a number of remaining teeth were negatively correlated with serum LDL-C level. After adjusting for age, gender, body mass index, smoking, FPG, and serum HbA1c and triglyceride levels, BI was found to be positively associated with dyslipidemia in T2DN patients with periodontitis.

CONCLUSION

T2DN patients with chronic periodontitis had a 2.355-fold higher risk of developing dyslipidemia, implying an important relationship between periodontitis and blood lipid control among T2DN patients.

Evaluation of the value of conventional and unconventional lipid parameters for predicting the risk of diabetes in a non-diabetic population

BACKGROUND

Conventional and unconventional lipid parameters are associated with diabetes risk, the comparative studies on lipid parameters for predicting future diabetes risk, however, are still extremely limited, and the value of conventional and unconventional lipid parameters in predicting future diabetes has not been evaluated. This study was designed to determine the predictive value of conventional and unconventional lipid parameters for the future development of diabetes.

METHODS

The study was a longitudinal follow-up study of 15,464 participants with baseline normoglycemia. At baseline, conventional lipid parameters such as low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) were measured/calculated, and unconventional lipid parameters such as non-HDL-C, remnant cholesterol (RC), LDL/HDL-C ratio, TG/HDL-C ratio, non-HDL/HDL-C ratio, TC/HDL-C ratio and RC/HDL-C ratio were calculated. Hazard ratio (HR) and 95% confidence interval (CI) were estimated by Cox proportional hazard regression adjusting for demographic and diabetes-related risk factors. The predictive value and threshold fluctuation intervals of baseline conventional and unconventional lipid parameters for future diabetes were evaluated by the time-dependent receiver operator characteristics (ROC) curve.

RESULTS

The incidence rate of diabetes was 3.93 per 1000 person-years during an average follow-up period of 6.13 years. In the baseline non-diabetic population, only TG and HDL-C among the conventional lipid parameters were associated with future diabetes risk, while all the unconventional lipid parameters except non-HDL-C were significantly associated with future diabetes risk. In contrast, unconventional lipid parameters reflected diabetes risk better than conventional lipid parameters, and RC/HDL-C ratio was the best lipid parameter to reflect the risk of diabetes (HR: 6.75, 95% CI 2.40-18.98). Sensitivity analysis further verified the robustness of this result. Also, time-dependent ROC curve analysis showed that RC, non-HDL/HDL-C ratio, and TC/HDL-C ratio were the best lipid parameters for predicting the risk of medium-and long-term diabetes.

CONCLUSIONS

Unconventional lipid parameters generally outperform conventional lipid parameters in assessing and predicting future diabetes risk. It is suggested that unconventional lipid parameters should also be routinely evaluated in clinical practice.

Pioglitazone — an oral antidiabetic agent and metabolic syndrome modulator. Can theory translate into practice?

The metabolic syndrome, associated with insulin resistance, is a cluster of cardiovascular risk factors which results in premature morbidity and mortality from atherosclerotic vascular disease. Pioglitazone, a peroxisome-proliferator-activated receptor gamma (PPARγ) agonist, is an insulin sensitiser with the ability to address key features of the metabolic syndrome: glucose intolerance including type 2 diabetes, hypertension, dyslipidaemia, the pro-coagulant state, endothelial dysfunction, inflammation and atherosclerosis. The greatest potential benefit of pioglitazone is to influence atherogenesis itself through its pleiotrophic effects on vascular risk factors. This has been tested by the PROactive study, results of which are published in September 2005.

Metformin use among individuals at risk for type 2 diabetes

Excess total and cardiovascular morbidity and mortality remain very high among those with type 2 diabetes versus those without diabetes. Clinical trials to lower blood glucose have been disappointing probably because the participants were too late in the natural history of diabetes and already had extensive vascular disease. Insulin resistance measured simply by elevated fasting blood insulin is an early marker of β-cell stress and peripheral insulin resistance. Metformin will prevent development of diabetes among patients with impaired fasting glucose but only for the short term. Metformin reduces risk of coronary heart disease. The drug is safe, low cost, and may also prevent cancer. The combination of diet and exercise followed by metformin in the early phase of "insulin resistance" may reduce or delay both atherosclerosis and arteriosclerosis complications associated with diabetes. Preventive therapy must begin much earlier than before clinical diagnosis of diabetes and aim to initially lower blood insulin levels or insulin resistance.

A replication study of GWAS-derived lipid genes in Asian Indians: the chromosomal region 11q23.3 harbors loci contributing to triglycerides

Recent genome-wide association scans (GWAS) and meta-analysis studies on European populations have identified many genes previously implicated in lipid regulation. Validation of these loci on different global populations is important in determining their clinical relevance, particularly for development of novel drug targets for treating and preventing diabetic dyslipidemia and coronary artery disease (CAD). In an attempt to replicate GWAS findings on a non-European sample, we examined the role of six of these loci (CELSR2-PSRC1-SORT1 rs599839; CDKN2A-2B rs1333049; BUD13-ZNF259 rs964184; ZNF259 rs12286037; CETP rs3764261; APOE-C1-C4-C2 rs4420638) in our Asian Indian cohort from the Sikh Diabetes Study (SDS) comprising 3,781 individuals (2,902 from Punjab and 879 from the US). Two of the six SNPs examined showed convincing replication in these populations of Asian Indian origin. Our study confirmed a strong association of CETP rs3764261 with high-density lipoprotein cholesterol (HDL-C) (p = 2.03×10(-26)). Our results also showed significant associations of two GWAS SNPs (rs964184 and rs12286037) from BUD13-ZNF259 near the APOA5-A4-C3-A1 genes with triglyceride (TG) levels in this Asian Indian cohort (rs964184: p = 1.74×10(-17); rs12286037: p = 1.58×10(-2)). We further explored 45 SNPs in a ∼195 kb region within the chromosomal region 11q23.3 (encompassing the BUD13-ZNF259, APOA5-A4-C3-A1, and SIK3 genes) in 8,530 Asian Indians from the London Life Sciences Population (LOLIPOP) (UK) and SDS cohorts. Five more SNPs revealed significant associations with TG in both cohorts individually as well as in a joint meta-analysis. However, the strongest signal for TG remained with BUD13-ZNF259 (rs964184: p = 1.06×10(-39)). Future targeted deep sequencing and functional studies should enhance our understanding of the clinical relevance of these genes in dyslipidemia and hypertriglyceridemia (HTG) and, consequently, diabetes and CAD.

Hyperglycemia in apolipoprotein E-deficient mouse strains with different atherosclerosis susceptibility

Background

Type 2 diabetes mellitus (T2DM) is associated with an increased risk of atherosclerotic vascular disease, but it is unknown whether the other way around is true too. C57BL/6 (B6) and BALB/cJ (BALB) are two mouse strains that differ markedly in their susceptibility to atherosclerosis. In this study we investigated the development of diet-induced T2DM in these two strains.

Methods and Results

When deficient in apolipoprotein E (apoE^-/-) and fed a Western diet for 12 weeks, atherosclerosis-susceptible B6 mice developed significant hyperglycemia. In contrast, atherosclerosis-resistant BALB apoE^-/- mice had much lower plasma glucose levels than B6.apoE^-/- mice on either chow or Western diet and during an intraperitoneal glucose tolerance test. In response to glucose BALB.apoE^-/- mice displayed both the first and second phases of insulin secretion but the second phase of insulin secretion was absent in B6.apoE^-/- mice. In response to insulin B6.apoE^-/- mice showed a deeper and longer-lasting fall in blood glucose levels while BALB.apoE^-/- mice showed little reduction in glucose levels. Pancreatic islet area of BALB.apoE^-/- mice on light microscopy nearly doubled the area of B6.apoE^-/- mice. Most circulating proinflammatory cytokines were lower in BALB.apoE^-/- than in B6.apoE^-/- mice on the Western diet, as determined by protein arrays. Increased macrophage infiltration in islets was observed in B6.apoE^-/- mice by immunostaining for Mac2 and also by flow cytometry.

Conclusion

This study demonstrates that defects in insulin secretion rather than defects in insulin resistance explain the marketed difference in susceptibility to T2DM in the B6.apoE^-/- and BALB.apoE^-/- mouse model. A smaller islet mass and more prominent islet inflammation may explain the vulnerability of B6.apoE^-/- mice to diet-induced diabetes.

Abnormal Cholesterol is Associated with Prefrontal White Matter Abnormalities among Obese Adults: A Diffusion Tensor Imaging Study

The brain is the most cholesterol-rich organ in the body. Although most of the cholesterol in the brain is produced endogenously, some studies suggest that systemic cholesterol may be able to enter the brain. We investigated whether abnormal cholesterol profiles correlated with diffusion-tensor-imaging-based estimates of white matter microstructural integrity of lean and overweight/obese (o/o) adults. Twenty-two lean and 39 obese adults underwent magnetic resonance imaging, kept a three-day food diary, and had a standardized assessment of fasting blood lipids. The lean group ate less cholesterol-rich food than o/o although both groups ate equivalent servings of food per day. Voxelwise correlational analyses controlling for age, diabetes, and white matter hyperintensities, resulted in two significant clusters of negative associations between abnormal cholesterol profile and fractional anisotropy, located in the left and right prefrontal lobes. When the groups were split, the lean subjects showed no associations, whereas the o/o group expanded the association to three significant clusters, still in the frontal lobes. These findings suggest that cholesterol profile abnormalities may explain some of the reductions in white matter microstructural integrity that are reported in obesity.

Achievement of lipid targets with the combination of rosuvastatin and fenofibric Acid in patients with type 2 diabetes mellitus

Objective

The objective of this study was to assess the proportion of patients with type 2 diabetes mellitus (T2DM) attaining individual and combined targets of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), non-HDL-C, and apolipoprotein B (ApoB) after treatment with rosuvastatin (R) + fenofibric acid (FA) compared with corresponding-dose R monotherapy.

Methods

This post hoc analysis evaluated data from the T2DM subset of patients with mixed dyslipidemia (LDL-C ≥130 mg/dL, HDL-C <40/50 mg/dL in men/women, and TG ≥150 mg/dL) from 2 randomized studies. Patients included in the analysis (N = 456) were treated with R (5, 10, or 20 mg), FA 135 mg, or R (5, 10, or 20 mg) + FA 135 mg for 12 weeks. Attainment of LDL-C <100 mg/dL, HDL-C >40/50 mg/dL in men/women, TG <150 mg/dL, non-HDL-C <130 mg/dL, ApoB <90 mg/dL, and the combined targets of these parameters was assessed.

Results

Treatment with R + FA resulted in a significantly higher proportion of patients achieving optimal levels of HDL-C (46.8% vs. 20.8%, P = 0.009 for R 10 mg + FA), TG (60.0% vs. 34.0%, P = 0.02 for R 10 mg + FA; 54.0% vs. 26.4%, P = 0.005 for R 20 mg + FA), non-HDL-C (55.1% vs. 36.4%, P = 0.04 for R 5 mg + FA), ApoB (58.0% vs. 36.4%, P = 0.02 for R 5 mg + FA); and the combined targets of LDL-C, HDL-C, and TG (28.3% vs. 8.3%, P = 0.02 for R 10 mg + FA) and all 5 parameters (26.1% vs. 8.3%, P = 0.03 for R 10 mg + FA) than corresponding-dose R monotherapies.

Conclusions

A significantly greater proportion of T2DM patients achieved individual and combined lipid targets when treated with the combination of R + FA than corresponding-dose R monotherapies.

Clinical implications of the BARI 2D and COURAGE trials of coronary artery disease

The results of the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) and Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) clinical trials raise important questions about the prevention and treatment of coronary heart disease among type 2 diabetics and nondiabetics. The BARI 2D and COURAGE trials showed that pharmacological therapy is as effective as surgery or angioplasty, because of the incidence of total mortality and cardiovascular disease events. The results are consistent with the clinical trials of lipid-lowering, antihypertensive therapy. The efficacy of lowering glycohemoglobin below 7% or benefits of specific glucose-lowering drugs is still unresolved. The BARI 2D trial focused on more advanced atherosclerotic disease. An important question is whether newly incident diabetics should be screened for subclinical atherosclerosis and treated aggressively with pharmacological therapy as in the BARI 2D trial. We are still uncertain whether raising high-density lipoprotein cholesterol will provide further benefit in reducing coronary heart disease. Better measurement of plaque morphology, determinants of hypercoagulable status, and drugs to reduce thrombosis and plaque are of high priority. Longer follow-up of the BARI 2D and COURAGE trials will provide important information about the risks of cardiovascular disease events and disability. It will be important but difficult to translate the results of the trials to community practice under the current health care system.

HDL and LDL cholesterol significantly influence beta-cell function in type 2 diabetes mellitus

PURPOSE OF REVIEW

Patients with type 2 diabetes mellitus (T2DM) display significant abnormalities in both LDL and HDL particles. Recent data suggest that these changes in lipoprotein particles could contribute to the pathogenesis of T2DM. In this review, we focus on these abnormalities and discuss their possible impact on beta-cell function and beta-cell mass.

RECENT FINDINGS

Infusion of reconstituted HDL in T2DM patients improves beta-cell function, whereas carriers of loss-of-function mutations in the cholesterol transporter ABCA1, who have decreased HDL levels, have impaired beta-cell function. In addition, recent studies show that HDL protects against stress-induced beta-cell apoptosis in vitro. Finally, increasing evidence points to a role for islet inflammation in the pathogenesis of T2DM. ABCA1 and ABCG1 may also modulate these inflammatory responses, suggesting an additional pathway by which HDL may impact T2DM.

SUMMARY

Recent findings indicate that HDL protects beta-cells from cholesterol-induced beta-cell dysfunction, stress-induced apoptosis and islet inflammation. As the protective properties of HDL are compromised in patients with metabolic syndrome and T2DM, dysfunctional HDL metabolism could contribute to the pathogenesis of T2DM. Therapeutic normalization of both the quantity and quality of HDL particles may be a novel approach to prevent or treat T2DM.

Dyslipidemia in children with type 2 diabetes vs. obesity

OBJECTIVE

To compare the frequency and severity of dyslipidemia between subjects with type 2 diabetes (T2DM) and non-diabetic obese group (OB) subjects, followed in a pediatric subspecialty clinic.

RESEARCH DESIGN AND METHODS

One hundred and four OB subjects seen consecutively by one physician and 67 pediatric subjects diagnosed with T2DM (negative antibodies) were screened from an institutional review board-approved database. Fifty-two T2DM and 75 OB subjects with fasting lipid profiles measured at one hospital's laboratory were included.

RESULTS

Both OB and T2DM subjects were predominantly Mexican American. Comparing T2DM at diagnosis or uncontrolled (UC) and OB, mean +/- SD age was 14.3 +/- 2.3 and 11.4 +/- 3.7 with body mass index-Z score of 2.02 +/- 0.67 and 2.46 +/- 0.45, respectively (both p < 0.01). Comparing lipid levels in T2DM to OB and National Health and Nutrition Examination Survey III, the percentage of subjects, respectively, with cholesterol >200 mg/dL (5.17 mmol/L) were 55.8, 22.7, and 10%; with low-density lipoprotein >130 mg/dL (3.36 mmol/L) were 39.4, 12.5, and 10%; with triglycerides >150 mg/dL (1.68 mmol/L) were 65.1, 38.7, and 12.5%; and with high-density lipoprotein <35 mg/dL (0.91 mmol/L) were 40, 22.2, and 10%. Over 80% of the T2DM subjects improved their lipid profile with improved glycemic control as hemoglobin A1c decreased from 10.85 +/- 2.17 to 7.6 +/- 2%.

CONCLUSIONS

Dyslipidemia is a frequent comorbidity of obesity and T2DM, starting in childhood, and poses a major public health risk. Dyslipidemia in pediatric subjects with UC T2DM is significantly worse than in OB subjects but is similar to OB subjects when diabetes was better controlled. Earlier use of lipid-lowering drugs should be considered in pediatric T2DM patients who achieve tight glycemic control, yet their dyslipidemia persists.

Effects of peroxisome proliferator-activated receptor (PPAR)-alpha and PPAR-gamma agonists on glucose and lipid metabolism in patients with type 2 diabetes mellitus

AIMS/HYPOTHESIS

The aim of the study was to examine the effects of pioglitazone (PIO), a peroxisome proliferator-activated receptor (PPAR)-gamma agonist, and fenofibrate (FENO), a PPAR-alpha agonist, as monotherapy and in combination on glucose and lipid metabolism.

SUBJECTS AND METHODS

Fifteen type 2 diabetic patients received FENO (n = 8) or PIO (n = 7) for 3 months, followed by the addition of the other agent for 3 months in an open-label study. Subjects received a 4 h hyperinsulinaemic-euglycaemic clamp and a hepatic fat content measurement at 0, 3 and 6 months.

RESULTS

Following PIO, fasting plasma glucose (FPG) (p < 0.05) and HbA(1c) (p < 0.01) decreased, while plasma adiponectin (AD) (5.5 +/- 0.9 to 13.8 +/- 3.5 microg/ml [SEM], p < 0.03) and the rate of insulin-stimulated total-body glucose disposal (R (d)) (23.8 +/- 3.8 to 40.5 +/- 4.4 micromol kg(-1) min(-1), p < 0.005) increased. After FENO, FPG, HbA(1c), AD and R (d) did not change. PIO reduced fasting NEFA (784 +/- 53 to 546 +/- 43 micromol/l, p < 0.05), triacylglycerol (2.12 +/- 0.28 to 1.61 +/- 0.22 mmol/l, p < 0.05) and hepatic fat content (20.4 +/- 4.8 to 10.2 +/- 2.5%, p < 0.02). Following FENO, fasting NEFA and hepatic fat content did not change, while triacylglycerol decreased (2.20 +/- 0.14 to 1.59 +/- 0.13 mmol/l, p < 0.01). Addition of FENO to PIO had no effect on R (d), FPG, HbA(1c), NEFA, hepatic fat content or AD, but triacylglycerol decreased (1.61 +/- 0.22 to 1.00 +/- 0.15 mmol/l, p < 0.05). Addition of PIO to FENO increased R (d) (24.9 +/- 4.4 to 36.1 +/- 2.2 micromol kg(-1) min(-1), p < 0.005) and AD (4.1 +/- 0.8 to 13.1 +/- 2.5 microg/ml, p < 0.005) and reduced FPG (p < 0.05), HbA(1c) (p < 0.05), NEFA (p < 0.01), hepatic fat content (18.3 +/- 3.1 to 13.5 +/- 2.1%, p < 0.03) and triacylglycerol (1.59 +/- 0.13 to 0.96 +/- 0.9 mmol/l, p < 0.01). Muscle adenosine 5'-monophosphate-activated protein kinase (AMPK) activity did not change following FENO; following the addition of PIO, muscle AMPK activity increased significantly (phosphorylated AMPK:total AMPK ratio 1.2 +/- 0.2 to 2.2 +/- 0.3, p < 0.01).

CONCLUSIONS/INTERPRETATION

We conclude that PPAR-alpha therapy has no effect on NEFA or glucose metabolism and that addition of a PPAR-alpha agonist to a PPAR-gamma agent causes a further decrease in plasma triacylglycerol, but has no effect on NEFA or glucose metabolism.

Lifestyle Intervention and Coronary Heart Disease Risk Factor Changes over 18 Months in Postmenopausal Women: The Women On the Move through Activity And Nutrition (WOMAN Study) Clinical Trial

OBJECTIVES

In this paper, we present the results of changes in risk factors by use of hormone therapy (HT) at 18 months in the Women On the Move through Activity and Nutrition (WOMAN) randomized trial.

METHODS

The trial was designed to test the hypothesis that aggressive dietary changes and increased physical activity to reduce weight, waist circumference (WC), glucose, insulin, and lipoproteins would reduce progression of subclinical atherosclerosis, carotid intimal media thickness and plaque, coronary artery calcification, and pulse wave velocity (PWV). The study focused on postmenopausal women (n = 508), mean age of 57, who were randomized to the Lifestyle Change (LC) or Health Education (HE) group.

RESULTS

At 18 months of follow-up, there was significant, 17 lb, weight loss and 10 cm WC decrease in the LC group. There were significant differences in changes in low-density lipoprotein cholesterol (LDL-C), insulin, glucose, large LDL, and LDL particles between the LC and HE groups. Risk factor changes were greater for women in the LC who lost a significant amount of weight (>or=18.8 lb). Participants at 18 months were subdivided into women who had stayed on HT, 125 (28%); stopped HT after randomization, 145 (33%); and not on HT at baseline but stopped an average of 7 months prior to randomization, 173 (39%). Weight loss in the LC was similar for all three groups, but LDL lipoprotein response was better for women who stopped HT after randomization or were not on HT at baseline.

CONCLUSIONS

The trial has been successful in increasing exercise and diet changes and reduction in weight and WC and variables related to metabolic syndrome.

Long-term effects of exenatide therapy over 82 weeks on glycaemic control and weight in over-weight metformin-treated patients with type 2 diabetes mellitus

AIM

The ability of the incretin mimetic exenatide to improve glycaemic control and reduce body weight was assessed over 82 weeks in patients with type 2 diabetes failing to achieve glycaemic control with maximally effective doses of metformin.

METHODS

In this interim 82-week analysis, 150 (total cohort) of an eligible population of 183 patients opted to continue exenatide treatment in an uncontrolled open-label extension of a 30-week double-blind, placebo-controlled trial. Of these, 92 patients (completer cohort) achieved 82 weeks of exenatide therapy. Patients continued metformin throughout the study.

RESULTS

At the end of the placebo-controlled trial, exenatide resulted in an haemoglobin A1c (HbA1c) reduction from baseline of -1.0 +/- 0.1% (mean +/- SE) (exenatide treatment arms), with durable HbA1c reductions after 82 weeks of -1.3 +/- 0.1%. The percent of patients who achieved HbA1c < or = 7% at weeks 30 and 82 was 46 and 59% respectively. After 30 weeks, exenatide caused a reduction in weight from baseline of -3.0 +/- 0.6 kg, with a progressive reduction in weight of -5.3 +/- 0.8 kg after 82 weeks. In addition, exenatide treatment produced clinically significant improvements in cardiovascular risk factors after 82 weeks. The most frequent adverse event after 30 and 82 weeks of exenatide was nausea, which was generally of mild-or-moderate intensity. It decreased in incidence after initiation in the controlled trial and the uncontrolled open-label extension. Hypoglycaemia was rare, with no severe events.

CONCLUSION

Exenatide was generally well tolerated, producing a durable reduction in HbA1c and a progressive reduction in weight over 82 weeks in patients with type 2 diabetes failing to achieve glycaemic control with metformin.

Beyond low-density lipoprotein: addressing the atherogenic lipid triad in type 2 diabetes mellitus and the metabolic syndrome

The metabolic syndrome and type 2 diabetes mellitus are both becoming more prevalent, and both increase the risk of cardiovascular disease. Many patients are not receiving appropriate treatment for the type of dyslipidemia that commonly occurs in these disorders--the so-called 'atherogenic lipid triad' of high serum triglyceride levels, low serum high-density lipoprotein cholesterol (HDL-C) levels, and a preponderance of small, dense, low-density lipoprotein cholesterol (LDL-C) particles. All of the processes involved in atherogenesis can be exacerbated by insulin resistance and/or the metabolic syndrome. Hypertriglyceridemia is a strong predictor of coronary heart disease. There is also an inverse relationship between serum levels of HDL-C and triglycerides in diabetic patients, with low serum HDL-C levels possibly representing an independent risk factor for cardiovascular disease. Small, dense, LDL-C particles are also highly atherogenic as they are more likely to form oxidized LDL and are less readily cleared. Insulin resistance, which is central to the metabolic syndrome and type 2 diabetes mellitus, leads to high levels of very low-density lipoprotein (VLDL), which contain a high concentration of triglycerides, resulting in high serum triglyceride levels and low serum HDL-C levels. Even though modification of the atherogenic lipid triad is probably one of the most effective methods of reducing cardiovascular risk, therapy for diabetic dyslipidemia is often directed to first lowering serum LDL-C levels with a HMG-CoA reductase inhibitor. This may leave substantial excess risk for cardiovascular disease in patients with these types of dyslipidemia. The results of recent trials evaluating HMG-CoA reductase inhibitors have been mixed, with two showing no significant effect on cardiovascular outcomes in subgroups of diabetic patients. The recent CARDS (Collaborative Atorvastatin Diabetes Study) showed that atorvastatin can reduce cardiovascular events in a trial specifically designed for a diabetic population, though the population had to have at least one other risk factor in addition to diabetes mellitus. Fibric acid derivatives, such as fenofibrate, bezafibrate and gemfibrozil, are potentially well suited to the treatment of dyslipidemia that is generally associated with type 2 diabetes mellitus and the metabolic syndrome, as they are usually more effective than HMG-CoA reductase inhibitors for normalizing serum levels of HDL-C and triglycerides. Promising results have been obtained from several trials of fibric acid derivatives including the BIP (Bezafibrate Infarction Prevention) study and the VA-HIT (Veterans Affairs Cooperative Studies Program HDL-C Intervention Trial; gemfibrozil). The FIELD (Fenofibrate Intervention and Event Lowering in Diabetes) trial, a clinical outcomes trial specifically designed to evaluate fenofibrate in a large population of patients with type 2 diabetes mellitus, many of whom have the metabolic syndrome, is underway. The FIELD trial results should shed light on the efficacy and safety of fenofibrate in reducing cardiovascular morbidity in diabetic and metabolic syndrome patients and on the safety profile of combination therapy with fenofibrate and a HMG-CoA reductase inhibitor.