Clinical significance of recent lipid trials on reducing risk in patients with type 2 diabetes mellitus

Glycosylated Haemoglobin (HbA1c) - A Marker of Circulating Lipids in Type 2 Diabetic Patients

BACKGROUND

Diabetic patients with concomitant dyslipidemia are often soft targets for cardiovascular disease and deaths. An early intervention to normalize circulating lipids has been shown to reduce cardiovascular morbidity and mortality. Glycosylated hemoglobin (HbA1c) is routinely used as a marker to indicate long-term glycemic control.

AIM

Our aim was to test whether HbA1c can serve as a marker of circulating lipids among Type 2 diabetic patients.

METHODS

The sera of 130 Type 2 diabetic patients was analyzed for fasting blood sugar (FBS), HbA1c and lipid profile consisting of total cholesterol (TC), triglycerides (TG), High-density Lipoprotein (HDL) cholesterol and LDL cholesterol. We divided the subjects based on their glycemic index into three groups; HbA1c< 6% as good, HbA1c>6% - <9% as poor and HbA1c>9% as worst glycemic control. One-way analysis of variance (ANOVA) and post-hoc Dunnett's multiple comparison tests was used to examine the significance levels for various biochemical parameters in age-categorized groups.

RESULTS

The mean ± SD levels of HbA1c was significantly higher in females (8.598 ± 2.284 %) compared to males (7.323±2.18 %). Older patients had HbA1c, FBS and lipid profile levels similar to younger ones. HbA1c showed direct and significant correlations with cholesterol, TG and LDL. Univariate analysis showed that HbA1c was a good predictor of circulating lipid levels.

CONCLUSION

The study indicates the usefulness of HbA1c as a marker for lipid profile for screening of diabetic patients at high risk of developing cardiovascular diseases.

Pioglitazone Randomised Italian Study on Metabolic Syndrome (PRISMA): effect of pioglitazone with metformin on HDL-C levels in Type 2 diabetic patients

BACKGROUND

Previous evidence indicates that pioglitazone may improve dyslipidemia in patients with Type 2 diabetes mellitus (T2DM).

AIM

The primary objective of this study was to evaluate the effect of either pioglitazone or placebo with metformin on levels of serum HDL cholesterol (HDL-C) in patients with T2DM. A secondary objective evaluated changes in metabolic syndrome (MS)-specific parameters.

SUBJECTS AND METHODS

This multicenter, double-blind, randomized study was performed in patients with T2DM treated with metformin and hemoglobin A1c (HbA1c) levels between 6-8%, central obesity and reduced HDL-C. MS was evaluated from global changes in parameter values and expressed as a single factorial score following multivariate analysis of each parameter. 213 patients (110 in the pioglitazone group and 103 in the placebo group) were available for intention-to-treat analysis.

RESULTS

Pioglitazone-treated patients showed a significant increase in HDL-C compared to placebo group (6.3 mg/dl vs 3.0 mg/dl; p<0.01) in addition to a greater reduction in the extent of MS (-13.2 vs -4.9; p=0.0055). Upon study completion, patients treated with pioglitazone had lower levels of HbA1c (6.41±0.65 vs 6.96±0.74%; p<0.001) and homeostasis model assessment-insulin resistance (HOMA-IR) (2.88±1.95 vs 4.68±3.63; p=0.013) and a reduction of the atherogenic LDL subfraction (pattern B) (-5.7%).

CONCLUSIONS

The beneficial effects observed in pioglitazone-treated patients in the present study, (i.e. the increase in HDL-C and the reduction of insulin resistance and atherogenic LDL subfractions), support findings from the PROactive trial, where pioglitazone showed pleiotropic effects and reduced death, fatal myocardial infarction (MI) and non-fatal MI in T2DM patients with MS. Furthermore, medication used in this study showed good tolerability.

Conceptual framework for research and clinical practice concerning cardiovascular health-related behaviors

OBJECTIVE: To present a conceptual framework based on the PRECEDE model conceived to guide research and the clinical practice of nurses in the clinical follow-up of patients with cardiovascular diseases. METHOD: The conceptual bases as well as the study designs used in the framework are discussed. The contextualization of the proposed structure is presented in the clinical follow-up of hypertensive patients. Examples of the intervention planning steps according to the intervention mapping protocol are provided. RESULTS: This conceptual framework coherently and rationally guided the diagnostic steps related to excessive salt intake among hypertensive individuals, as well as the development and assessment of specific interventions designed to change this eating behavior. CONCLUSION: The use of this conceptual framework enables a greater understanding of health-related behaviors implied in the development and progression of cardiovascular risk factors and is useful in proposing nursing interventions with a greater chance of success. This model is a feasible strategy to improve the cardiovascular health of patients cared for by the Brazilian Unified Health System.

Efficacy and safety of coadministration of fenofibrate and ezetimibe compared with each as monotherapy in patients with type IIb dyslipidemia and features of the metabolic syndrome: a prospective, randomized, double-blind, three-parallel arm, multicenter, comparative study

BACKGROUND

Patients with type IIb, or mixed, dyslipidemia have high levels of low-density lipoprotein cholesterol (LDL-C) with predominance of small dense LDL particles, high levels of triglycerides (TG), and low levels of high-density lipoprotein cholesterol (HDL-C). Fenofibrate significantly reduces TG and, more moderately, LDL-C, increases HDL-C and produces a shift from small to large LDL particle size; the main effect of ezetimibe is a reduction in LDL-C levels. Combined treatment with fenofibrate and ezetimibe may correct all the abnormalities of type IIb dyslipidemia.

OBJECTIVE

To assess the efficacy and safety of coadministration of fenofibrate (NanoCrystal(R)) and ezetimibe in patients with type IIb dyslipidemia and the metabolic syndrome compared with administration of fenofibrate and ezetimibe alone (ClinicalTrials.gov Identifier: NCT00349284; Study ID: CLF178P 04 01).

METHODS

This was a prospective, randomized, double-blind, three-parallel arm, multicenter, comparative study. Sixty ambulatory patients (mean age 56 years; 50% women, 50% men) were treated in each group. For inclusion in the study, patients were required to have LDL-C >or=4.13 mmol/L (>or=160 mg/dL), TG >or=1.71 mmol/L and <or=4.57 mmol/L (>or=150 mg/dL and <or=405 mg/dL), and at least two of the following National Cholesterol Education Program Adult Treatment Panel III criteria for the metabolic syndrome: low HDL-C or increased fasting plasma glucose, blood pressure, or waist circumference. Patients received fenofibrate 145 mg, ezetimibe 10 mg, or coadministration of both (fenofibrate/ezetimibe) daily for 12 weeks. The outcome measures were changes in lipids and related parameters, apolipoproteins, glucose metabolism parameters, and high-sensitivity C-reactive protein (hsCRP). Fenofibrate/ezetimibe was more effective than either fenofibrate or ezetimibe in reducing LDL-C (-36.2% vs -22.4% and -22.8%, respectively), non-HDL-C (-36.2% vs -24.8% and -20.9%, respectively), total cholesterol (TC) [-27.9% vs -18.9% and -17.1%, respectively], apolipoprotein B (-33.3% vs -24.5% and -18.7%, respectively), TC/HDL-C ratio (-34.2% vs -23.0% and -17.0%, respectively), and apolipoprotein B/apolipoprotein AI ratio (-37.5% vs -27.0% and -17.7%, respectively) [p < 0.001 for all comparisons between fenofibrate/ezetimibe and monotherapies].

RESULTS

Fenofibrate/ezetimibe was as effective as fenofibrate and more effective than ezetimibe in reducing remnant-like particle cholesterol (-36.2% and -30.7% vs -17.3%, respectively), and in increasing LDL size (+2.1% and +1.9% vs + 0.7%, respectively), apolipoprotein AI (+7.9% and +5.1% vs +0.2%, respectively) and apolipoprotein AII (+24.2% and +21.2% vs +2.7%, respectively). Fenofibrate/ezetimibe and fenofibrate were equally effective in reducing TG (both -38.3%) and in increasing HDL-C (+11.5% and + 7.9%, respectively; p = 0.282). Ezetimibe had minor effects on TG (-10.4%) and HDL-C (+2.2%). Among patients with low HDL-C at baseline (<1.29 mmol/L [<50 mg/dL] in women, <1.03 mmol/L [<40 mg/dL] in men), normalization of HDL-C was observed in 52.9% with fenofibrate/ezetimibe and in 58.8% with fenofibrate, compared with 20.0% with ezetimibe. Changes in hsCRP were -25.9% with fenofibrate/ezetimibe, -27.8% with fenofibrate, and -10.2% with ezetimibe (not statistically significant). None of the treatments altered glucose metabolism parameters.

CONCLUSION

In patients with type IIb dyslipidemia and features of the metabolic syndrome, coadministration of fenofibrate 145 mg and ezetimibe 10 mg daily was more effective than either monotherapy in reducing LDL-C, non-HDL-C, apolipoprotein B, and cardiovascular risk ratios, and was as effective as fenofibrate 145 mg alone in reducing TG and in increasing HDL-C in patients with low baseline HDL-C levels.

Nonfasting lipids, lipoproteins, and apolipoproteins in individuals with and without diabetes: 58 434 individuals from the Copenhagen General Population Study

BACKGROUND

Whether lipid profiles should be collected from fasting or nonfasting individuals is controversial, particularly in the diabetic population. We examined the influence of normal food intake on lipid profiles in diabetic and nondiabetic individuals.

METHODS

We assessed plasma concentrations of lipids, lipoproteins, apolipoproteins, and albumin as a function of time since the last meal in 58 434 individuals (participation rate 45%) from the general population, 2270 of whom had diabetes mellitus.

RESULTS

Similar patterns in the measured constituents were observed in the diabetic and nondiabetic populations. Triglycerides remained increased for 6-7 h in both populations after the last meal, whereas LDL cholesterol and albumin but not apolipoprotein B were reduced in both populations up to 5 h after normal food intake; after adjustment for hemodilution on the basis of albumin concentrations, the LDL cholesterol reductions were no longer present. Maximum observed mean differences from fasting concentrations in diabetic patients were -0.6 mmol/L, 0 mmol/L, 0.2 mmol/L, and 0.08 g/L (8 mg/dL) for LDL cholesterol, HDL cholesterol, triglycerides, and apolipoprotein B, respectively, and, correspondingly, -0.3 mmol/L, 0 mmol/L, 0.2 mmol/L, and 0.03 g/L (3 mg/dL) in individuals without diabetes.

CONCLUSIONS

Triglycerides increased up to 0.2 mmol/L after normal food intake in individuals with and without diabetes, whereas the postprandial reductions in LDL cholesterol observed in both populations likely were caused by hemodilution due to fluid intake. No statistically significant differences in postprandial apolipoprotein B concentrations were found. These data may be useful for discussion during revisions of guidelines for lipid measurements in individuals with or without diabetes.

Long-Term clinical outcomes according to initial management and thrombolysis in myocardial infarction risk score in patients with acute non-ST-segment elevation myocardial infarction

PURPOSE

There is still debate about the timing of revascularization in patients with acute non-ST-segment elevation myocardial infarction (NSTEMI). We analyzed the long-term clinical outcomes of the timing of revascularization in patients with acute NSTEMI obtained from the Korea Acute Myocardial Infarction Registry (KAMIR).

MATERIALS AND METHODS

2,845 patients with acute NSTEMI (65.6 +/- 12.5 years, 1,836 males) who were enrolled in KAMIR were included in the present study. The therapeutic strategy of NSTEMI was categorized into early invasive (within 48 hours, 65.8 +/- 12.6 years, 856 males) and late invasive treatment (65.3 +/- 12.1 years, 979 males). The initial- and long-term clinical outcomes were compared between two groups according to the level of Thrombolysis In Myocardial Infarction (TIMI) risk score.

RESULTS

There were significant differences in-hospital mortality and the incidence of major adverse cardiac events during one-year clinical follow-up between two groups (2.1% vs. 4.8%, p < 0.001, 10.0% vs. 13.5%, p = 0.004, respectively). According to the TIMI risk score, there was no significant difference of long-term clinical outcomes in patients with low to moderate TIMI risk score, but significant difference in patients with high TIMI risk score (>or= 5 points).

CONCLUSIONS

The old age, high Killip class, low ejection fraction, high TIMI risk score, and late invasive treatment strategy are the independent predictors for the long-term clinical outcomes in patients with NSTEMI.

The comparative effectiveness of rosuvastatin vs. other statins in patients with an increased risk of failure to reach NCEP ATP III goal

BACKGROUND

Previous studies have demonstrated that failure to reach National Cholesterol Education Program (NCEP) target low-density lipoprotein cholesterol (LDL-C) goal increases the risk of cardiovascular events. Ability to meet goal may be impacted by the choice of statin therapy.

PURPOSE

This study compares rosuvastatin to other statin therapies among patients presenting with risk factors associated with failure to reach NCEP goal.

METHODS

Retrospective analysis using medical and pharmacy claims linked to laboratory results from a national health plan encompassing private and MedicareAdvantage enrollees age > or = 18 years and newly treated with statins from 1 August 2003 to 28 February 2005. Predictors of failure to reach goal were statin treatment group, age, gender, NCEP risk level, per cent reduction required to attain goal and days from index to LDL-C measurement.

RESULTS

Of 11,814 eligible patients, 9.6% were initiated on rosuvastatin, 54.2% atorvastatin, 17.9% simvastatin, 7.1% pravastatin, 2.0% fluvastatin and 9.3% lovastatin. Independent predictors of failure to reach goal included > or = 15% LDL-C reduction required to reach goal, and high and moderate NCEP risk status. In the subset of patients at higher risk of failure to reach goal, rosuvastatin demonstrated a significantly lower rate of failure to achieve goal than atorvastatin, simvastatin, pravastatin, fluvastatin or lovastatin.

CONCLUSIONS

Real-world factors associated with high risk of failure to reach goal may be used in identifying patients more likely to succeed on rosuvastatin compared with other statins. Low-risk patients needing < 15% LDL-C reduction would be suitable candidates for initiation of most other statins, specifically simvastatin, which has recently become available in the generic form.

Atorvastatin has hypolipidemic and anti-inflammatory effects in apoE/LDL receptor-double-knockout mice

Statins are first-line pharmacotherapeutic agents for hypercholesterolemia treatment in humans. However the effects of statins in animal models of atherosclerosis are not very consistent. Thus we wanted to evaluate whether atorvastatin possesses hypolipidemic and anti-inflammatory effects in mice lacking apolipoprotein E/low-density lipoprotein receptor (apoE/LDLR-deficient mice). Two-month-old female apoE/LDLR-deficient mice (n=24) were randomly subdivided into 3 groups. The control group of animals (n=8) was fed with the western type diet (atherogenic diet) and in other two groups atorvastatin was added to the atherogenic diet at the dosage of either 10 mg/kg or 100 mg/kg per day for a period of 2 months. Biochemical analysis of lipids, ELISA analysis of monocyte chemotactic protein-1 (MCP-1) in blood, quantification of lesion size and expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular cell adhesion molecule-1 (ICAM-1) in the atherosclerotic lesion by means of immunohistochemistry and Western blot analysis were performed. The biochemical analysis showed that administration of atorvastatin (100 mg/kg/day) significantly decreased level of total cholesterol, lipoproteins (VLDL and LDL), triacylglycerol, and moreover significantly increased level of HDL. ELISA analysis showed that atorvastatin significantly decreased levels of MCP-1 in blood and immunohistochemical and Western blot analysis showed significant reduction of VCAM-1 and ICAM-1 expression in the vessel wall after atorvastatin treatment (100 mg/kg/day). In conclusion, we demonstrated here for the first time strong hypolipidemic and anti-inflammatory effects of atorvastatin in apoE/LDLR-deficient mice. Thus, we propose that apoE/LDLR-deficient mice might be a good animal model for the study of statin effects on potential novel markers involved in atherogenesis and for the testing of potential combination treatment of new hypolipidemic substances with statins.

Clinical significance of HbA1c as a marker of circulating lipids in male and female type 2 diabetic patients

Diabetic patients with accompanied (but often unnoticed) dyslipidemia are soft targets of cardiovascular deaths. An early intervention to normalize circulating lipids has been shown to reduce cardiovascular complications and mortality. Glycated hemoglobin (HbA(1c)) is a routinely used marker for long-term glycemic control. This investigation is an attempt to evaluate the diagnostic value of HbA(1c) in predicting diabetic dyslipidemia. Venous blood samples were collected from 2,220 type 2 diabetic patients (ages, 35-91 years; male/female ratio, 1.07). The sera were analyzed for HbA(1c), fasting blood glucose (FBG), total cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL) and low-density lipoprotein cholesterol (LDL). The levels of HbA(1c) did not differ significantly between males (8.33 +/- 0.06%) and females (8.47 +/- 0.07%), whereas female patients had significantly higher FBG (10.01 +/- 0.13 mmol/l) than males (9.31 +/- 0.11 mmol/l). HbA(1c) showed direct and significant correlations with cholesterol, triglycerides and LDL and inverse correlation with HDL. Female diabetic patients had significantly higher levels of serum cholesterol (5.42 +/- 0.03 vs. 5.18 +/- 0.03 mmol/l) and HDL (1.32 +/- 0.01 vs. 1.12 +/- 0.01 mmol/l) as compared to males. There was no significant difference in triglycerides and LDL between the two genders. Older patients (>70 years) had significantly lower FBG, cholesterol, triglycerides and LDL. There was a linear and significant increase in triglycerides in the patients of both genders with impaired glycemic control. Both male and female patients with worse glycemic control (HbA(1c) > 9%) had significantly high cholesterol and LDL levels. Serum HDL showed a significant and inverse relationship with uncontrolled hyperglycemia in females but not in males. These findings clearly suggest that HbA(1c) can provide valuable supplementary information about the extent of circulating lipids besides its primary role in monitoring long-term glycemic control. Further studies are warranted to reinforce the potential of HbA(1c) as a biomarker for screening of high-risk diabetic patients.

Hypertriglyceridemia and cardiovascular risk reduction

BACKGROUND

Elevated triglyceride (TG) levels are prevalent among the US population, often occurring in persons who are overweight or obese, or who have type 2 diabetes or the metabolic syndrome. There is evidence that elevated TG levels may be a significant independent risk factor for coronary heart disease (CHD), particularly in women.

OBJECTIVE

This article reviews data on the epidemiology, associated risks, treatment, and prevention of hypertriglyceridemia, including recommended TG goals and available TG-lowering agents.

METHODS

MEDLINE was searched for articles published from 1990 through 2006 using the terms hypertriglyceridemia, dyslipidemia, and coronary heart disease, with subheadings for risk, statins, niacin, fibrates, thiazolidinediones, and omega-3 fatty acids. The reference lists of relevant articles were examined for additional citations. Publications discussing the epidemiology of hypertriglyceridemia, CHD risk, treatment guidelines for lipid management, clinical trials involving TG-lowering drugs, and outcomes for lipid-modifying therapies were selected for review.

RESULTS

Concern over the increasing rate of hypertriglyceridemia and its deleterious health consequences is reflected in the most recent National Cholesterol Education Program guidelines. Several lipid-lowering agents are available, including statins, fibrates, niacin, thiazolidinediones, and prescription omega-3 fatty acids. Clinical trials of these drugs have reported lowering of TG by 7% to 50%. Along with lifestyle changes, the use of combination pharmacotherapy to reduce lipid levels (including TG) may be an effective strategy in patients with dyslipidemia.

CONCLUSION

Use of strategies to manage TG levels, along with low-density lipoprotein cholesterol levels, is warranted to help reduce the risk of CHD.

Therapeutic regulation of endothelial dysfunction in type 2 diabetes mellitus

Endothelial dysfunction is universal in diabetes, being intimately involved with the development of cardiovascular disease. The pathogenesis of endothelial dysfunction in diabetes is complex. It is initially related to the effects of fatty acids and insulin resistance on 'uncoupling' of both endothelial nitric oxide synthase activity and mitochondrial function. Oxidative stress activates protein kinase C (PKC), polyol, hexosamine and nuclear factor kappa B pathways, thereby aggravating endothelial dysfunction. Improvements in endothelial function in the peripheral circulation in diabetes have been demonstrated with monotherapies, including statins, fibrates, angiotensin-converting enzyme (ACE) inhibitors, metformin and fish oils. These observations are supported by large clinical end point trials. Other studies show benefits with certain antioxidants, L-arginine, folate, PKC-inhibitors, peroxisome proliferator activated receptor (PPAR)-alpha and -gamma agonists and phosphodiesterase (PDE-5) inhibitors. However, the benefits of these agents remain to be shown in clinical end point trials. Combination treatments, for example, statins plus ACE inhibitors and statins plus fibrates, have also been demonstrated to have additive benefits on endothelial function in diabetes, but there are no clinical outcome data to date. Measurement of endothelial dysfunction in cardiovascular research can provide fresh opportunities for exploring the mechanism of benefit of new therapeutic regimens and for planning and designing large clinical trials.