Prevalence and associated factors of uncontrolled hyperlipidemia among Thai patients with diabetes and clinical atherosclerotic cardiovascular diseases: a cross-sectional study

Objectives

The research aimed to determine the prevalence and associated factors of uncontrolled hyperlipidemia among Thai patients with the disease and Clinical ASCVD.

Results

A total of 1,527 Thai diabetic patients with a history of ASCVD were included in the study. Uncontrolled hyperlipidemia was detected among 1,216 patients (79.6%; 95% CI 77.6–81.7). The independent factors associated with uncontrolled hyperlipidemia included being female (adjusted odds ratio (AORs); 1.5, 95% CI 1.2–2.0), using thiazolidinedione (AORs; 1.7, 95% CI 1.1–2.7), community hospital (AORs; 4.3, 95% CI 1.0–18.0) and BMI level at 18.5–22.9 kg/m² (AORs; 2.2, 95% CI 1.2–4.0), 23.0–24.9 kg/m² (AORs; 1.8 95% CI 0.9–3.3), 25.0–29.9 kg/m² (AORs; 2.3 95% CI 1.3–4.3) and ≥ 30 kg/m² (AORs; 2.5 95% CI 1.3–4.9).

Combination lipid therapy in type 2 diabetes mellitus

INTRODUCTION

A significant drop in cardiovascular risk has been seen in patients with type 2 diabetes treated with statins. However, this cardiovascular risk remains high, compared with nondiabetic individuals. This is partly due to the typical abnormalities of diabetic dyslipidemia - hypertriglyceridemia and decreased high-density lipoprotein cholesterol (HDL-C) - that are uncontrolled by statins. For this reason, combination lipid therapy may be considered in patients with type 2 diabetes.

AREAS COVERED

This review presents the main reasons for a combination lipid therapy in type 2 diabetes and the effects of several drugs, including fibrates, pioglitazone, niacin and omega 3, on diabetic dyslipidemia and the prevention of cardiovascular events. The real cardiovascular benefit of fibrates in patients with type 2 diabetes is not totally clear, but they may produce a significant benefit in patients with type 2 diabetes and diabetic dyslipidemia (hypertriglyceridemia, low HDL-C). Pioglitazone, which reduces triglycerides and increases HDL-C, has been shown to reduce the risk for major cardiovascular events in type 2 diabetes. Niacin and omega 3 fatty acids have a positive effect on diabetic dyslipidemia, but warrants clinical trials to demonstrate a clear cardiovascular benefit in type 2 diabetes.

EXPERT OPINION

Although combination lipid therapy seems to be useful to control diabetic dyslipidemia, the efficacy of such combined therapies on significantly reducing cardiovascular risk has still to be confirmed by additional clinical trials.

Effect of rosiglitazone on progression of atherosclerosis: insights using 3D carotid cardiovascular magnetic resonance

BACKGROUND

There is recent evidence suggesting that rosiglitazone increases death from cardiovascular causes. We investigated the direct effect of this drug on atheroma using 3D carotid cardiovascular magnetic resonance.

RESULTS

A randomized, placebo-controlled, double-blind study was performed to evaluate the effect of rosiglitazone treatment on carotid atherosclerosis in subjects with type 2 diabetes and coexisting vascular disease or hypertension. The primary endpoint of the study was the change from baseline to 52 weeks of carotid arterial wall volume, reflecting plaque burden, as measured by carotid cardiovascular magnetic resonance. Rosiglitazone or placebo was allocated to 28 and 29 patients respectively. Patients were managed to have equivalent glycemic control over the study period, but in fact the rosiglitazone group lowered their HbA1c by 0.88% relative to placebo (P < 0.001). Most patients received a statin or fibrate as lipid control medication (rosiglitazone 78%, controls 83%). Data are presented as mean +/- SD. At baseline, the carotid arterial wall volume in the placebo group was 1146 +/- 550 mm3 and in the rosiglitazone group was 1354 +/- 532 mm3. After 52 weeks, the respective volumes were 1134 +/- 523 mm3 and 1348 +/- 531 mm3. These changes (-12.1 mm3 and -5.7 mm3 in the placebo and rosiglitazone groups, respectively) were not statistically significant between groups (P = 0.57).

CONCLUSION

Treatment with rosiglitazone over 1 year had no effect on progression of carotid atheroma in patients with type 2 diabetes mellitus compared to placebo.

Fluvastatin/fenofibrate vs. simvastatin/ezetimibe in patients with metabolic syndrome: different effects on LDL-profiles

BACKGROUND

Patients with metabolic syndrome (MS) and type 2 diabetes (T2DM) show increased risk for coronary artery disease. Lipoprotein metabolism is characterized by elevated triglycerides (TG), low high-density lipoprotein cholesterol (HDL-C) and predominance of atherogenic small, dense low-density lipoprotein (sdLDL), while low-density lipoprotein (LDL) cholesterol is only slightly elevated.

METHODS

Multicentre, randomized, open-label cross-over study investigating the effect of combination of fluvastatin/fenofibrate (80/200 mg) (F&F) on LDL-subfractions compared with combination of simvastatin/ezetimibe (20/10 mg) (S&E) in patients with MS/T2DM.

RESULTS

Seventy-five patients were randomized, 69 completed the study and LDL-subfractions of 56 patients were analysed. Thirty-eight out of 56 patients (68%) showed a profile dominated by sdLDL. In these, TG and total cholesterol (TC) were elevated compared with non-sdLDL patients. In all patients, reduction of TC and LDL cholesterol (LDL-C) by S&E was stronger than by F&F. The increase of HDL-C was stronger with S&E in the non-sdLDL group, whereas in the sdLDL group, there was no difference between treatments. In non-sdLDL patients, there was no effect on TG or LDL-radius. However, in the sdLDL group, F&F was more effective in reducing TG and increased LDL radius, whereas S&E reduced LDL radius even further.

CONCLUSIONS

S&E is more efficient in reducing TC and LDL-C. This is also true for HDL-C increase in non-sdLDL patients. However, in patients with sdLDL, F&F was more efficient in reducing TG and increasing LDL radius.

The differential effects of thiazolidindiones on atherogenic dyslipidemia in type 2 diabetes: what is the clinical significance?

BACKGROUND

Diabetic dyslipidemia is typically characterized by an increase in plasma triglycerides, a decrease in high-density lipoprotein cholesterol and a concomitant increase in atherogenic small dense low-density lipoproteins. Thiazolidindiones are able to lower the levels of fasting glucose and glycated hemoglobin significantly by improving insulin sensitivity, as well as improving some aspects of diabetic dyslipidemia: total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol tend to increase while triglycerides are generally decreased.

OBJECTIVE

This paper reviewed the effects of pioglitazone and rosiglitazone on atherogenic diabetic dyslipidemia, in particular on small dense low-density lipoprotein particles.

METHODS

A literature search (by Medline and Scopus) was performed up to 15 March 2008. The authors also manually reviewed the references of selected articles for any pertinent material.

RESULTS

Pioglitazone showed an additional beneficial effect on triglycerides, high-density lipoprotein cholesterol and the levels of small dense low-density lipoprotein compared to rosiglitazone.

CONCLUSIONS

Since recent studies have suggested that these agents may also have a differential effect on long-term cardiovascular end-points despite similar improvements in glycated hemoglobin and insulin sensitivity, the different impact on atherogenic diabetic dyslipidemia may help to explain these findings.

Pioglitazone and rosiglitazone have different effects on serum lipoprotein particle concentrations and sizes in patients with type 2 diabetes and dyslipidemia

OBJECTIVE

Associated with insulin resistance in type 2 diabetes are increased serum triglycerides, decreased HDL cholesterol, and a predominance of large VLDL, small LDL, and small HDL particles. The comparative effects of thiazolidinedione insulin sensitizers on serum lipoprotein particle concentrations and sizes in type 2 diabetes are not known. We studied the effects of pioglitazone (PIO) and rosiglitazone (ROSI) treatments on serum lipoprotein particle concentrations and sizes in type 2 diabetic patients with dyslipidemia.

RESEARCH DESIGN AND METHODS

This is a prospective, randomized, double-blind, multicenter, parallel-group study. After a 4-week placebo washout period, patients randomized to PIO (n = 369) were treated with 30 mg q.d. for 12 weeks followed by 45 mg q.d. for another 12 weeks, while patients randomized to ROSI (n = 366) were treated with 4 mg q.d. followed by 4 mg b.i.d. for the same intervals. Lipoprotein subclass particle concentrations and sizes were determined by proton nuclear magnetic resonance spectroscopy at baseline and end point (PIO [n = 333] and ROSI [n = 325] patients).

RESULTS

PIO treatment increased total VLDL particle concentration less than ROSI treatment and decreased VLDL particle size more than ROSI. PIO treatment reduced total LDL particle concentration, whereas ROSI treatment increased it. Both treatments increased LDL particle size, with PIO treatment having a greater effect. Whereas PIO treatment increased total HDL particle concentration and size, ROSI treatment decreased them; both increased HDL cholesterol levels.

CONCLUSIONS

PIO and ROSI treatments have different effects on serum lipoprotein subclass particle concentrations and sizes in patients with type 2 diabetes and dyslipidemia.

Long-term effects on lipids and lipoproteins of pioglitazone versus gliclazide addition to metformin and pioglitazone versus metformin addition to sulphonylurea in the treatment of type 2 diabetes

AIMS/HYPOTHESIS

The aim of this study was to determine the long-term effects of pioglitazone add-on to metformin or sulphonylurea on plasma lipids and lipoproteins.

MATERIALS AND METHODS

The effects of pioglitazone were studied in two clinical trials in patients with inadequately controlled type 2 diabetes (HbA1c > or =7.5 and < or =11%). In the first trial, patients currently receiving metformin were randomised to pioglitazone (15-45 mg/day, n=317) or gliclazide (80-320 mg/day, n=313) add-on therapy. In the second study, pioglitazone (15-45 mg/day, n=319) or metformin (850-2,550 mg/day, n=320) was added to sulphonylurea therapy. Patients were force-titrated to the maximum tolerated dose of add-on therapy, which was maintained to the 2-year endpoint.

RESULTS

There were no statistically significant differences between the groups with respect to HbA1c reduction from baseline to week 104. Whether added to metformin or sulphonylurea, pioglitazone caused highly significant greater decreases in triglycerides and increases in HDL cholesterol from baseline to week 104 than treatments with gliclazide or metformin add-on therapies (p< or =0.001). The triglyceride reductions noted with pioglitazone were maintained over time, with decreases of 16-18% at 1 year and 17-23% at 2 years. In the pioglitazone groups, the improvement in HDL cholesterol at 1 year was maintained, with 21-22% augmentations at 2 years (p<0.001 between-group difference). Small but statistically significant greater reductions in LDL cholesterol were observed with gliclazide vs pioglitazone add-on to metformin and metformin vs pioglitazone add-on to sulphonylurea (p<0.001 for between-group difference). In the pioglitazone groups, mean LDL cholesterol at 2 years was similar to mean baseline LDL cholesterol.

CONCLUSIONS/INTERPRETATION

After 2 years, highly significant decreases in triglycerides and increases in HDL cholesterol that were sustained over time or even improved were observed when pioglitazone was added to metformin or sulphonylurea therapy. These effects of pioglitazone on lipids may be potentially beneficial in reducing cardiovascular risk in type 2 diabetes.

Effect of Divalproex on Metabolic Parameters Is Dose Related in Migraine Prophylaxis

OBJECTIVE

To examine the metabolic effects of three divalproex dosing regimens in patients with migraine.

BACKGROUND

Epidemiological and clinical studies have demonstrated a strong association between serum lipid levels and the development of coronary artery disease. Thus, it is important to understand the impact of chronically administered medications on serum lipids. Metabolic properties of divalproex, an approved and commonly used treatment for migraine prophylaxis, have not been systematically studied in patients with migraine.

METHODS

Adult patients with migraine were randomized to receive one of three daily doses of divalproex (500 mg [n = 45], 1000 mg [n = 43], or 1500 mg [n = 44]) or placebo (n = 44) for 12 weeks. Post hoc analyses were performed to determine the effects of divalproex on total cholesterol, glucose, weight, and body mass index (BMI).

RESULTS

The treatment groups were similar at baseline based on demographic and clinical characteristics and the use of concomitant medications. Divalproex resulted in a dose-related mean decrease from baseline in total cholesterol: -5.7 mg/dL or 3% reduction with 500 mg/day; -8.4 mg/dL or 4% reduction with 1000 mg/day; and -12.8 mg/dL or 7% reduction with 1500 mg/day (P < .05 for 1500 mg/day vs. placebo). There were no differences between any divalproex dose group and placebo for mean change from baseline in glucose, weight, or BMI.

CONCLUSIONS

Divalproex results in a dose-dependent reduction in serum cholesterol within the first 3 months of therapy, with no significant change in serum glucose or BMI.

A long-term comparison of pioglitazone and gliclazide in patients with Type 2 diabetes mellitus: a randomized, double-blind, parallel-group comparison trial

AIMS

This study compared the effects of pioglitazone and gliclazide on metabolic control in drug-naive patients with Type 2 diabetes mellitus.

METHODS

A total of 1270 patients with Type 2 diabetes were randomized in a parallel-group, double-dummy, double-blind study. Patients with poorly controlled Type 2 diabetes (HbA1c 7.5-11%), despite dietary advice, received either pioglitazone up to 45 mg once daily or gliclazide up to 160 mg two times daily. Primary efficacy endpoint was change in HbA1c from baseline to the end of the study. Secondary efficacy endpoints included change in fasting plasma glucose, fasting plasma insulin and plasma lipids. At selected centres, oral glucose tolerance tests were performed and C-peptide and pro-insulin levels were measured.

RESULTS

Mean HbA1c values decreased by the same amount in the two treatment groups from baseline to week 52 [pioglitazone: -1.4%; gliclazide: -1.4%; (90% CI: -0.18 to 0.02)]. A significantly greater mean reduction in fasting plasma glucose was observed in the pioglitazone group (2.4 mmol/l) than in the gliclazide group [2.0 mmol/l; treatment difference -0.4 mmol/l in favour of pioglitazone; P = 0.002; (95% CI: -0.7 to -0.1)]. Improvements in high-density lipoprotein cholesterol (HDL-C) and total cholesterol/HDL-C were greater with pioglitazone than with gliclazide (P < 0.001). The frequencies of adverse events were comparable between the two treatment groups, but more hypoglycaemic events were reported for gliclazide, whereas twice as many patients reported oedema with pioglitazone than with gliclazide.

CONCLUSIONS

Pioglitazone monotherapy was equivalent to gliclazide in reducing HbA1c, with specific differences between treatments in terms of mechanism of action, plasma lipids and adverse events.

Sustained effects of pioglitazone vs. glibenclamide on insulin sensitivity, glycaemic control, and lipid profiles in patients with Type 2 diabetes

AIMS

This study compared the effects of 52 weeks' treatment with pioglitazone, a thiazolidinedione that reduces insulin resistance, and glibenclamide, on insulin sensitivity, glycaemic control, and lipids in patients with Type 2 diabetes.

METHODS

Patients with Type 2 diabetes were randomized to receive either pioglitazone (initially 30 mg QD, n = 91) or micronized glibenclamide (initially 1.75 mg QD, n = 109) as monotherapy. Doses were titrated (to 45 mg for pioglitazone and 10.5 mg for glibenclamide) to achieve glycaemic targets during the next 12 weeks: fasting blood glucose of < or = 7 mmol/l and 1-h postprandial blood glucose of < or = 10 mmol/l. Patients were maintained on the titrated dose for 40 weeks.

RESULTS

Pioglitazone significantly increased insulin sensitivity compared with glibenclamide, as assessed by homeostasis model assessment (17.0% vs. -13.0%; P < 0.001), quantitative insulin sensitivity check index (0.011 vs. -0.007; P < 0.001) and fasting serum insulin (-1.3 pmol/l vs. 23.8 pmol/l; P = 0.007). The glibenclamide group had significantly lower HbA1c than the pioglitazone group after 12 weeks of therapy (7.8% vs. 8.3%, P = 0.015), but significantly higher HbA1c after 52 weeks of therapy (7.8% vs. 7.2%, P = 0.001). Pioglitazone significantly (vs. glibenclamide) increased mean HDL-C (P < 0.001), decreased mean triglycerides (P = 0.019), and decreased mean atherogenic index of plasma (AIP; P = 0.001) and mean total cholesterol/HDL-C (P = 0.004), without significantly elevating mean total cholesterol or mean LDL-C compared with glibenclamide. CONCLUSIONS These data suggest that the effects of pioglitazone are more sustained than those of glibenclamide for improving insulin sensitivity in patients with Type 2 diabetes, and that 52 weeks' treatment with pioglitazone has favourable effects on glycaemic control and lipoprotein profile.

Clinical interest of PPARs ligands

Cardiovascular disease is significantly increased in patients with metabolic syndrome and type 2 diabetes. Several factors such as chronic hyperglycemia, lipId abnormalities, endothelium dysfunction, inflammation, oxIdative stress, increased thrombosis and decreased fibrinolysis are likely to promote cardiovascular events in these patients. Because of positive effects on glucose homeostasis, lipId metabolism, proteins involved in all stages of atherogenesis, endothelium function, inflammation, thrombosis and fibrinolysis, PPARS alpha (fibrates) and PPARs gamma (glitazones) agonists are good candIdates to reduce cardiovascular disease, more precisely in subjects with metabolic syndrome or type 2 diabetes. PPARS alpha agonists (fibrates) are potent hypolipIdemic agents increasing plasma HDL-cholesterol and reducing free fatty acIds, triglycerIdes, LDL-cholesterol and the number of small dense LDL pArticles. Moreover, they reduce vascular inflammation and thrombosis, promote fibrinolysis and inhibit the production of the vasoconstrictor factor, endothelin-1, by the endothelium. They have been shown, in clinical trials, to reduce cardiovascular disease, more particularly in patients displaying lipId abnormalities typical of metabolic syndrome and type 2 diabetes (high triglycerIdes, low HDL-cholesterol). PPARS gamma agonists (glitazones) have not only beneficial effects on glucose homeostasis, by increasing insulin sensitivity and reducing blood glucose level but also on lipId metabolism by elevating plasma HDL-cholesterol, decreasing free fatty acIds and the number of small dense LDL pArticles, and for pioglitazone by reducing plasma triglycerIdes. Furthermore, they diminish vascular inflammation and vasoconstriction, inhibit monocyte chemotaxis, proliferation and migration of smooth muscle cells, in the vascular wall and decrease the production of adhesion molecules and metalloproteinases. PPARs gamma agonists (glitazones) have been shown to reduce the development of atherosclerotic lesions in rats. The potential clinical benefit of PPARs gamma agonists on the reduction of cardiovascular disease, in type 2 diabetic patients, will be specified by the ongoing intervention studies.

A comparison of the effects of thiazolidinediones and metformin on metabolic control in patients with type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus is a condition characterized by impaired insulin secretion and resistance to insulin-mediated glucose uptake and utilization. A number of oral antidiabetic medication are available for its treatment, including metformin and the thiazolidinediones (TZDs). The TZDs have been shown to improve insulin resistance, and it has been suggested that metformin has similar effects. Although both types of agents improve glycemic control, their mechanisms of action and effects on metabolic processes differ.

OBJECTIVE

The goal of this review was to compare the effects of TZDs and metformin on metabolic control in patients with type 2 diabetes.

METHODS

A search of MEDLINE to March 2004 using the terms metformin and biguanides, and thiazolidinediones and glitazones was conducted to identify preclinical and clinical studies focusing on the mechanisms of action and comparative effects of TZDs and metformin. Also searched were published abstracts from recent major diabetes and endocrinology conferences.

RESULTS

In the studies reviewed, both TZDs and metformin demonstrated the ability to improve glycemic control, although long-term monotherapy with TZDs appeared to be more effective than metformin. There continues to be debate about whether metformin is more effective than TZDs in terms of inhibition of hepatic glucose production. However, various studies have found TZDs to be more effective in promoting an increase in whole-body insulin sensitivity. With respect to lipid metabolism, patients who received TZDs had a greater reduction in concentrations of both plasma triglycerides and free fatty acids. Metformin was more effective in promoting weight loss in patients with type 2 diabetes, although TZDs may decrease visceral fat levels. Treatment with either metformin or TZDs was associated with a reduction in the risk of cardiovascular disease, although the mechanisms by which they accomplished this seem to differ.

CONCLUSIONS

The evidence suggests that the predominant effect of metformin is inhibition of hepatic glucose production, whereas the primary effects of TZDs is reduction of insulin resistance and promotion of peripheral glucose uptake. TZDs appear to have more positive effects on other metabolic processes and to be associated with greater improvements in cardiovascular risk factors compared with metformin.

Effects of pioglitazone and glimepiride on glycemic control and insulin sensitivity in Mexican patients with type 2 diabetes mellitus: A multicenter, randomized, double-blind, parallel-group trial

BACKGROUND

Pioglitazone and glimepiride improve glycemic control in patients with type 2 diabetes mellitus by different mechanisms. Pioglitazone is a thiazolidinedione that reduces insulin resistance, and glimepiride is a sulfonylurea insulin secretagogue.

OBJECTIVE

The goals of this study were to compare changes in measures of glycemic control and insulin sensitivity in Mexican patients with type 2 diabetes who received pioglitazone or glimepiride for 1 year.

METHODS

This was a multicenter, 52-week, double-blind, parallel-group trial. Patients were randomized to receive monotherapy with either glimepiride (2 mg QD initially) or pioglitazone (15 mg QD initially). Doses were titrated (maximal doses: pioglitazone 45 mg, glimepiride 8 mg) to achieve glycemic targets (fasting blood glucose < or =7 mmol/L and 1-hour postprandial blood glucose < or =10 mmol/L). Insulin sensitivity (primary end point) was evaluated in terms of the Homeostasis Model Assessment for Insulin Sensitivity (HOMA-S), the Quantitative Insulin Sensitivity Check Index (QUICKI), and fasting serum insulin (FSI) concentrations. Glycemic control was evaluated in terms of glycosylated hemoglobin (HbA(1c)) values and fasting plasma glucose (FPG) concentrations. Patients were encouraged to maintain their individual diet and exercise regimens throughout the study.

RESULTS

Two hundred forty-four patients (125 women, 119 men; all but 1 Hispanic) were randomized to receive pioglitazone (n = 121) or glimepiride (n = 123). In the intent-to-treat sample, pioglitazone and glimepirede produced comparable reductions in HbA(1c) from baseline to the end of the study (-0.78% and -0.68%, respectively). The pioglitazone group had significantly higher HbA(1c) values compared with the glimepiride group after 12 weeks of therapy (8.66% vs 7.80%; P = 0.007) but had significantly lower values after 52 weeks (7.46% vs 7.77%; P = 0.027). Pioglitazone significantly reduced FPG compared with glimepiride (-0.6 vs 0.6 mmol/L; P = 0.01). Pioglitazone therapy was associated with significant increases in insulin sensitivity (reduced insulin resistance), whereas glimepiride had no effect. HOMA-S values changed 18.0% for pioglitazone and -7.9% for glimepiride (P < 0.001), QUICKI values changed a respective 0.013 and -0.007 (P < 0.001), and FSI values were -21.1 and 15.1 pmol/L (P< 0.001). Both drugs were well tolerated, with pioglitazone associated with more peripheral edema (number of treatment-emergent cases: 35/121[28.9%] vs 17/123 [13.8%]; P = 0.005) and fewer hypoglycemic episodes (19 [15.7%] vs 38 [30.9%]; P = 0.024). The incidence of weight gain was not significantly different between treatment groups.

CONCLUSIONS

These data suggest that long-term treatment with pioglitazone enhances insulin sensitivity relative to glimepiride in Mexican patients with type 2 diabetes and that pioglitazone may have a more sustained antihyperglycemic effect.

Pioglitazone plus a sulphonylurea or metformin is associated with increased lipoprotein particle size in patients with type 2 diabetes

OBJECTIVE

To determine the effect of pioglitazone plus metformin or a sulphonylurea on lipoprotein particle size and subclass distribution in patients with type 2 diabetes.

METHODS

Lipid profiles were determined for blood samples from patients participating in two randomised, double-blind, 24-week studies of pioglitazone 30 mg or 45 mg daily plus either metformin or a sulphonylurea.

RESULTS

Samples from 177 patients were evaluated; 96 of these patients received a sulphonylurea, and 81 received metformin. Pioglitazone combination treatment produced significant increases from baseline for average and peak low-density lipoprotein (LDL) particle size at weeks 12 and 24 (p<0.0001 for each; range 0.29-0.39 nm for average and 0.36-0.55 nm for peak particle size, respectively). Significant shifts in high-density lipoprotein (HDL) and LDL distribution showed an increase in large particles and a decrease in small particles. For pioglitazone plus metformin, significant increases in levels of apolipoprotein (Apo) Al, Apo Al/All-containing HDL, and lipoprotein(a) also were noted, whereas Apo B levels decreased.

CONCLUSIONS

These observed changes are thought to affect the atherogenic profile positively. Therefore, pioglitazone combination treatment may lead to decreased cardiovascular risk in patients with type 2 diabetes.

Pioglitazone, insulinosensibilité et diabète de type 2 : données récentes

Thiazolidinediones ("glitazones") were recently added to the oral treatment of type 2 diabetes. Two glitazones are available in France, pioglitazone and rosiglitazone, which progressively were granted broader therapeutic indications since their launch in 2002. This review presents the most recent pioglitazone pharmacological and clinical data, with a particular emphasis on the QUARTET clinical study program results. Available information generates perspectives and hopes: prevention of the progressive decline in beta-pancreatic cell function (and possibly, prevention of type 2 diabetes in at-risk subjects), cardiovascular prevention in type 2 diabetic patients depending on the results of the ongoing prospective morbi-mortality studies in high risk type 2 diabetic patients.

Pioglitazone reduces atherogenic dense LDL particles in nondiabetic patients with arterial hypertension: a double-blind, placebo-controlled study

OBJECTIVE

The oral antidiabetic agent pioglitazone improves insulin sensitivity and glycemic control and appears to lower atherogenic dense LDL in type 2 diabetes. Insulin resistance may occur frequently in nondiabetic patients with hypertension. This study is the first to report the effect of pioglitazone on LDL subfractions in normolipidemic, nondiabetic patients with arterial hypertension.

RESEARCH DESIGN AND METHODS

We performed a monocentric, double-blind, randomized, parallel-group comparison of 45 mg pioglitazone (n = 26) and a placebo (n = 28), each given once daily for 16 weeks. Fifty-four moderately hypertensive patients (LDL cholesterol, 2.8 +/- 0.8 mmol/l; HDL cholesterol, 1.1 +/- 0.3 mmol/l; triglycerides, 1.4 mmol/l (median; range 0.5-7.1) were studied at baseline and on treatment.

RESULTS

At baseline, dense LDLs were elevated (apolipoprotein [apo]B in LDL-5 plus LDL-6 >250 mg/l) in 63% of all patients. Sixteen weeks of treatment with pioglitazone did not significantly change triglycerides, total, LDL, and HDL cholesterol. However, pioglitazone reduced dense LDLs by 22% (P = 0.024). The mean diameter of LDL particles increased from 19.83 +/- 0.30 to 20.13 +/- 0.33 nm (P < 0.001 vs. placebo), whereas the mean LDL density decreased from 1.0384 +/- 0.0024 to 1.0371 +/- 0.0024 kg/l (P = 0.005 vs. placebo). The effect of pioglitazone on LDL size and density was independent of fasting triglycerides and HDL cholesterol at baseline and of changes in fasting triglycerides and HDL cholesterol.

CONCLUSIONS

The prevalence of atherogenic dense LDL in nondiabetic, hypertensive patients is similar to patients with type 2 diabetes. Pioglitazone significantly reduces dense LDL independent from fasting triglycerides and HDL cholesterol. The antiatherogenic potential of pioglitazone may thus be greater than that expected from its effects on triglycerides, LDL, and HDL cholesterol alone.