A comparison between sitagliptin or glibenclamide in addition to metformin + pioglitazone on glycaemic control and ß-cell function: the triple oral therapy.

AIMS: To evaluate which triple oral therapy between metformin + pioglitazone + sitagliptin and metformin + pioglitazone + glibenclamide can be more useful in improving glycaemic control and should be preferred in clinical practice. METHODS: During the 2-year run-in period, patients were instructed to take metformin monotherapy for the first year, then a combination of metformin and pioglitazone for the second year, then patients were randomized to add glibenclamide or sitagliptin to the dual combination of metformin and pioglitazone for another year. RESULTS: Body weight reached with sitagliptin at 36 months was lower than that reached with glibenclamide. Fasting plasma insulin and homeostasis model assessment of insulin resistance were significantly increased by triple therapy with glibenclamide and decreased by that with sitagliptin. While sitagliptin did not change homeostasis model assessment of ß-cell function, this value was significantly increased by glibenclamide. Fasting plasma proinsulin was not influenced by triple oral therapy including glibenclamide, while it was decreased by the therapy including sitagliptin compared to glibenclamide. Triple oral therapy with sitagliptin better improved ß-cell function measures compared with the glibenclamide therapy. CONCLUSIONS: Sitagliptin should be preferred to glibenclamide as an addition to the metformin + pioglitazone combination for its better protection of ß-cell secretion and its neutral effect on body weight.

Exenatide plus metformin compared with metformin alone on ß-cell function in patients with Type 2 diabetes.

AIM: To quantify how much exenatide added to metformin improves ß-cell function, and to evaluate the impact on glycaemic control, insulin resistance and inflammation compared with metformin alone. METHODS: A total of 174 patients with Type 2 diabetes with poor glycaemic control were instructed to take metformin for 8 ± 2 months, then they were randomly assigned to exenatide (5 µg twice a day for the first 4 weeks and forced titration to 10 µg twice a day thereafter) or placebo for 12 months. At 12 months we evaluated anthropometric measurements, glycaemic control, insulin resistance and ß-cell function variables, glucagon, adiponectin, high sensitivity-C reactive protein and tumour necrosis factor-α. Before and after 12 months, patients underwent a combined euglycaemic hyperinsulinaemic and hyperglycaemic clamp, with subsequent arginine stimulation. RESULTS: Exenatide + metformin gave a greater decrease in body weight, glycaemic control, fasting plasma proinsulin and insulin and their ratio, homeostasis model assessment for insulin resistance (HOMA-IR), and glucagon values and a greater increase in C-peptide levels, homeostasis model assessment ß-cell function index (HOMA-ß) and adiponectin compared with placebo + metformin. Exenatide + metformin decreased waist and hip circumference, and reduced concentrations of high sensitivity-C reactive protein and tumour necrosis factor-α. Exenatide + metformin gave a greater increase in M value (+34%), and disposition index (+55%) compared with placebo + metformin; first (+21%) and second phase (+34%) C-peptide response to glucose and C-peptide response to arginine (+25%) were also improved by exenatide + metformin treatment, but not by placebo + metformin. CONCLUSION: Exenatide is effective not only on glycaemic control, but also in protecting ß-cells and in reducing inflammation.

Effects of one year treatment of vildagliptin added to pioglitazone or glimepiride in poorly controlled type 2 diabetic patients.

The aim of the study was to compare the effects of vildagliptin added to pioglitazone or glimepiride on metabolic and insulin resistance related-indices in poorly controlled type 2 diabetic patients (T2DM). 168 patients with T2DM were randomized to take either pioglitazone 30 mg once a day plus vildagliptin 50 mg twice a day or glimepiride 2 mg 3 times a day plus vildagliptin 50 mg twice a day. We evaluated body weight, body mass index (BMI), glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), postprandial plasma glucose (PPG), fasting plasma insulin (FPI), homeostasis model assessment insulin resistance index (HOMA-IR), homeostasis model assessment beta-cell function index (HOMA-beta), fasting plasma proinsulin (FPPr), proinsulin/fasting plasma insulin ratio (Pr/FPI ratio), adiponectin (ADN), resistin (R), tumor necrosis factor-alpha (TNF-alpha), and high sensitivity C-reactive protein (Hs-CRP) at their baseline values, and after 3, 6, 9, and 12 months of treatment. We observed a similar improvement of HbA1c, FPG, PPG, and Hs-CRP compared to baseline in the 2 groups. Fasting plasma insulin, FPPr, Pr/FPI ratio, R, and TNF-alpha were significantly decreased and ADN was significantly increased with pioglitazone plus vildagliptin, but not with glimepiride plus vildagliptin. HOMA-IR, and HOMA-beta values obtained with pioglitazone plus vildagliptin were significantly better than the values obtained with glimepiride plus vildagliptin. Pioglitazone plus vildagliptin were found to be more effective in preserving beta-cell function, and in reducing insulin resistance, and inflammatory state parameters.

Exenatide versus glibenclamide in patients with diabetes.

BACKGROUND: Incretin-based therapies have provided additional options for the treatment of type 2 diabetes mellitus. The aim of our study was to evaluate the effects of exenatide compared to glibenclamide on body weight, glycemic control, beta-cell function, insulin resistance, and inflammatory state in patients with diabetes. METHODS: One hundred twenty-eight patients with uncontrolled type 2 diabetes mellitus receiving therapy with metformin were randomized to take exenatide 5 microg twice a day or glibenclamide 2.5 mg three times a day and titrated to exenatide 10 microg twice a day or glibenclamide 5 mg three times a day. We evaluated body weight, body mass index (BMI), glycated hemoglobin (HbA(1c)), fasting plasma glucose (FPG), postprandial plasma glucose (PPG), fasting plasma insulin (FPI), homeostasis model assessment insulin resistance (HOMA-IR) index, homeostasis model assessment beta-cell function (HOMA-beta) index, plasma proinsulin (PPr), PPr/FPI ratio, resistin, retinol binding protein-4 (RBP-4), and high-sensitivity C-reactive protein (Hs-CRP) at baseline and after 3, 6, 9, and 12 months. RESULTS: Body weight and BMI decreased with exenatide and increased with glibenclamide. A similar improvement of HbA(1c), FPG, and PPG was obtained in both groups, whereas FPI decreased with exenatide and increased with glibenclamide. The HOMA-IR index decreased and the HOMA-beta index increased with exenatide but not with glibenclamide. A decrease of PPr was reported in both groups, but only glibenclamide decreased the PPr/FPI ratio. Resistin and RBP-4 decreased with exenatide and increased with glibenclamide. A decrease of Hs-CRP was obtained with exenatide, whereas no variations were observed with glibenclamide. CONCLUSIONS: Both exenatide and glibenclamide gave a similar improvement of glycemic control, but only exenatide gave improvements of insulin resistance and beta-cell function, giving also a decrease of body weight and of inflammatory state.

Efficacy and safety of ezetimibe/simvastatin association on non-diabetic and diabetic patients with polygenic hypercholesterolemia or combined hyperlipidemia and previously intolerant to standard statin treatment.

BACKGROUND AND OBJECTIVE: One of the problems associated with reaching the low-density lipoprotein cholesterol (LDL-C) target during statin treatment is the emergence of laboratory or clinical side effects. The aim of our study was to evaluate the prevalence of statin-associated adverse events in diabetic and non-diabetic patients affected by polygenic hypercholesterolemia or combined hyperlipidemia and the efficacy and tolerability of treatment with ezetimibe/simvastatin 10/10 mg/day on the same subjects experiencing the adverse events. METHODS: Consecutively enrollment of patients affected by polygenic hypercholesterolemia or combined hyperlipidemia with or without type 2 diabetes mellitus. Each Centre used any of the available statins on the basis of current clinical judgement and monitored enrolled patients for adverse events during the following 2 years. Those patients with moderate adverse events suspended the current statin therapy for 1 month (washout period), and then were shifted to treatment with ezetimibe/simvastatin 10/10 mg/day and again monitored for adverse events in the following 6 months. We assessed body mass index, glycated haemoglobin, fasting plasma glucose, total cholesterol, LDL-C, high-density lipoprotein cholesterol, triglycerides, alanine aminotransferase, aspartate aminotransferase, creatinine phosphokinase and monitored adverse events such as asthenia and myalgia. RESULTS AND DISCUSSION: All 1170 Caucasian patients affected by polygenic hypercholesterolemia obtained a significant reduction in LDL-C during the observation period (P < 0*05), while those with combined hyperlipidemia also showed a reduction in TG plasma level (P < 0*05) and a significant increase in HDL-C (P < 0*05). Patients affected by polygenic hypercholesterolemia experiencing adverse event under statin treatment obtained a significantly lower reduction than those tolerating the treatment (P < 0*001). The prevalence of adverse events under statin treatment was 4*9% in non-diabetic patients with polygenic hypercholesterolemia, 8*6% in those with combined hyperlipidemia, 7*1% in diabetic patients with polygenic hypercholesterolemia and 7*6% in those with combined hyperlipidemia. Six months after the shift to treatment with ezetimibe/simvastatin 10/10 mg, all patients experienced a significant improvement in LDL-C, TG and HDL-C plasma level. No adverse event was registered during the ezetimibe/simvastatin 10/10 mg treatment period. It seems that previous side effects observed with statins did not re-appear with the administration of ezetimibe/simvastatin 10/10 mg/day. CONCLUSIONS: The efficacy and adverse effect profile of the ezetimibe and simvastatin combination appear to be good for both diabetic and nondiabetic patients, and in both conditions.

Matrix metalloproteinase-2 and -9 levels in obese patients.

The data reported in literature revealed a novel function for matrix metalloproteinases (MMPs) as modulators of adipogenesis. However, their expression profile and role in the cellular microenvironment during obesity-mediated adipose tissue development remain poorly defined. The authors hypothesized that MMP-2 and MMP-9 levels might be abnormal in obesity, reflecting alterations in extracellular matrix (ECM) turnover. One hundred and sixty three obese patients and 165 controls were enrolled. The following were measured: body mass index (BMI), waist circumference (WC), fasting plasma glucose (FPG), fasting plasma insulin (FPI), homeostasis model assessment (HOMA) index, systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (Tg), lipoprotein(a) (Lp(a)), and plasma levels of MMP-2 and MMP-9. A significant increase of BMI and WC (p< .0001) was observed in obese patients. No FPG change was present in obese group, whereas FPI and HOMA index increases (p< .0001) were obtained in obese patients compared to control subjects. No SBP and DBP variations were observed in obese group. Significant TC and LDL-C increases (p< .0001) were present in obese patients, whereas no HDL-C, Tg, and Lp(a) changes were obtained in both groups. MMP-2 and MMP-9 levels were significantly higher in obese group (p< .0001). Plasma levels of MMP-2 and MMP-9 are increased in obese patients which may reflect abnormal ECM metabolism.

Metabolic effects of pioglitazone and rosiglitazone in patients with diabetes and metabolic syndrome treated with metformin.

BACKGROUND: Metformin is considered the gold standard for type 2 diabetes treatment as monotherapy and in combination with sulphonylureas and insulin, whereas the combination of metformin with thiazolidinediones is relatively less studied. The aim of the present study was to assess the differential effect on glycaemic metabolism and lipid variables of the combination of metformin plus pioglitazone or metformin plus rosiglitazone in diabetic patients with metabolic syndrome. METHODS: All patients began metformin and were randomized to receive pioglitazone or rosiglitazone for 12 months. We assessed body mass index, glycated haemoglobin, fasting plasma glucose, postprandial plasma glucose, fasting plasma insulin, postprandial plasma insulin, homeostasis model assessment index, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, apolipoprotein A-I, and apolipoprotein B. RESULTS: Significant decreases in glycated haemoglobin, fasting plasma glucose, postprandial plasma glucose, fasting plasma insulin, and postprandial plasma insulin were seen after 9 and 12 months in both groups. Homeostasis model assessment index improved at 12 months in both groups. Significant total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, apolipoprotein A-I, and apolipoprotein B improvement was observed in pioglitazone group after 12 months, but not in the rosiglitazone group. These variations were significant between groups. CONCLUSION: The combination of metformin plus thiazolidinediones was able to improve glycaemic control compared with previous therapy. Pioglitazone was associated with a significant improvement in lipid and lipoprotein variables.

Effects of rosiglitazone and pioglitazone combined with metformin on the prothrombotic state of patients with type 2 diabetes mellitus and metabolic syndrome.

In this multicentre, randomized, double-blind, controlled, parallel-group trial, 103 patients with type 2 diabetes mellitus and metabolic syndrome were randomized to receive one of two thiazolidinediones--pioglitazone or rosiglitazone--in combination with 1500 mg/day of metformin, increasing up to 3000 mg/day, for 12 months. Anthropometric, metabolic, coagulation and fibrinolysis parameters were assessed at baseline and after 3, 6, 9 and 12 months. Significant decreases in glycosylated haemoglobin, fasting plasma glucose and post-prandial plasma glucose levels were seen after 9 and 12 months in both groups, and significant decreases in fasting plasma insulin and post-prandial plasma insulin levels were seen after 12 months in both groups. In both groups, improvement in the homeostasis model assessment index compared with baseline was obtained only after 12 months. Plasminogen activator inhibitor-1 levels were significantly lower in both groups after 12 months compared with baseline values. In patients with type 2 diabetes mellitus and metabolic syndrome, the combination of metformin plus thiazolidinediones improved glycaemic control and produced a slight but significant reduction in plasminogen activator inhibitor-1 levels.

Metformin-pioglitazone and metformin-rosiglitazone effects on non-conventional cardiovascular risk factors plasma level in type 2 diabetic patients with metabolic syndrome.

BACKGROUND AND OBJECTIVE: Metformin is considered the gold standard for type 2 diabetes treatment as monotherapy and in combination with sulphonylureas and insulin. The combination of metformin with thiazolidinediones is less well studied. The aim of the present study was to assess the differential effect, and tolerability, of metformin combined with pioglitazone or rosiglitazone on glucose, coagulation and fibrinolysis parameters in patients with type 2 diabetes mellitus and metabolic syndrome. METHODS: This 12-month, multicentre, double-blind, randomized, controlled, parallel-group trial was conducted at three study sites in Italy. We assessed patients with type 2 diabetes mellitus (duration >or=6 months) and with metabolic syndrome. All patients were required to have poor glycaemic control with diet, or experienced adverse effects with diet and metformin, administered up to the maximum tolerated dose. Patients were randomized to receive either pioglitazone or rosiglitazone self-administered for 12 months. We assessed body mass index (BMI), glycaemic control [glycosylated haemoglobin (HbA(1c)), fasting and postprandial plasma glucose and insulin levels (FPG, PPG, FPI, and PPI respectively), homeostasis model assessment (HOMA) index], lipid profile [total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triglycerides (TG)], lipoprotein (a) [Lp(a)] and homocysteine (HCT) at baseline and at 3, 6, 9 and 12 months of treatment. RESULTS AND DISCUSSION: No BMI change was observed at 3, 6, 9 and 12 months in either group. Significant HbA(1c) decreases were observed at 9 and 12 months in both groups. After 9 and 12 months, mean FPG and PPG levels decreased in both groups. Decreases in FPI and PPI were observed at 9 and 12 months compared with the baseline in both groups. Furthermore, in both groups, the HOMA index improved but only at 12 months. Significant TC, LDL-C, HDL-C, TG improvement was present in the pioglitazone group at 12 months compared with the baseline values, and these variations were significantly different between groups. No TC, LDL-C, TG improvement was present in the rosiglitazone group after 12 months. Significant Lp(a) and HCT improvement was present in the pioglitazone group at 12 months compared with the baseline values, and Lp(a) change was significant compared with the rosiglitazone group. Significant HCT decrease was observed in the rosiglitazone group at the end of the study. In our type 2 diabetic patients, both drugs were safe and effective for glycaemic control and improving HCT plasma levels. However, long-term treatment with metformin plus pioglitazone significantly reduced Lp(a) plasma levels, whereas metformin + rosiglitazone did not. CONCLUSION: For patients with type 2 diabetes mellitus and metabolic syndrome, combined treatment with metformin and rosiglitazone or pioglitazone is safe and effective, However, the pioglitazone combination also reduced the plasma Lp(a) levels whereas the rosiglitazone combination did not.

Differential effect of glimepiride and rosiglitazone on metabolic control of type 2 diabetic patients treated with metformin: a randomized, double-blind, clinical trial.

AIM: Accumulating evidence suggests that combination therapy using oral antidiabetic agents with different mechanisms of action may be highly effective in achieving and maintaining target blood glucose levels. The aim of our study is to evaluate the differential effect on glucose and lipid parameters of the association between glimepiride plus metformin and rosiglitazone plus metformin in patients affected by type 2 diabetes and metabolic syndrome. METHODS: Patients were enroled, evaluated and followed at two Italian centres. We evaluated 99 type 2 diabetic patients with metabolic syndrome (48 males and 47 females; 23 males and 24 females, aged 52 +/- 5 with glimepiride; 25 males and 23 females, aged 54 +/- 4 with cglitazone). All were required to have been diagnosed as being diabetic for at least 6 months and did not have glycaemic control with diet and oral hypoglycaemic agents such as sulphonylureas or metformin, both to the maximum tolerated dose. All patients took a fixed dose of metformin, 1500 mg/day. We administered glimepiride (2 mg/day) or rosiglitazone (4 mg/day) in a randomized, controlled, double-blind clinical study. We evaluated body mass index (BMI), glycaemic control, lipid profile [total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol and triglycerides] and lipoprotein parameters [apolipoprotein A-I and apolipoprotein B (Apo B)] during 12 months of this treatment. RESULTS: A total of 95 patients completed the study. Significant BMI decrease was observed at 12 months in glimepiride and rosiglitazone group (p < 0.05 and p < 0.01 respectively) as well as of glycated haemoglobin decrease (p < 0.05 and p < 0.01 respectively), mean fasting plasma glucose and postprandial plasma glucose levels (p < 0.05 and p < 0.01 respectively). A decrease in fasting plasma insulin and postprandial plasma insulin at 12 months (p < 0.05 and p < 0.01 respectively) compared with the baseline value in rosiglitazone group was observed. Furthermore, homeostasis model assessment index improvement was obtained only at 9 and 12 months (p < 0.05 and p < 0.01 respectively) compared with the baseline value in rosiglitazone group. Significant TC, LDL-C and Apo B improvement (p < 0.05 respectively) was present in glimepiride group after 12 months compared with the baseline values, and these variations were significant (p < 0.05) between groups. Of the 95 patients who completed the study, 8.5% of patients in glimepiride group and 12.5% of patients in rosiglitazone group had side-effects (p = not significant). Four patients had transient side-effects in glimepiride group and six patients in rosiglitazone group. Altogether, we did not have statistically significant changes in transaminases. CONCLUSIONS: The rosiglitazone-metformin association significantly improve the long-term control of all insulin-resistance-related parameters in comparison with the glimepiride-metformin-treated group. On the other side, glimepiride treatment is associated to a slight improvement in cholesterolaemia, not observed in the rosiglitazone-treated patients.

Efficacy and safety comparative evaluation of orlistat and sibutramine treatment in hypertensive obese patients.

AIM: The aim of our study was to comparatively evaluate the efficacy and safety of orlistat and sibutramine treatment in obese hypertensive patients, with a specific attention to cardiovascular effects and to side effects because of this treatment. METHODS: Patients were enrolled, evaluated and followed at three Italian Centres of Internal Medicine. We evaluated 115 obese and hypertensive patients. (55 males and 60 females; 26 males and 29 females, aged 50 +/- 4 with orlistat; 28 males and 30 females, aged 51 +/- 5 with sibutramine). All patients took antihypertensive therapy for at least 6 months before the study. We administered orlistat or sibutramine in a randomized, controlled, double-blind clinical study. We evaluated anthropometric variables, blood pressure and heart rate (HR) during 12 months of this treatment. RESULTS: A total of 113 completed the 4 weeks with controlled energy diet and were randomized to double-blind treatment with orlistat (n = 55) or sibutramine (n = 58). Significant body mass index (BMI) improvement was present after 6 (p < 0.05), 9 (p < 0.02), and 12 (p < 0.01) months in both groups, and body weight (BW) improvement was obtained after 9 (p < 0.05) and 12 (p < 0.02) months in both groups. Significant waist circumference (WC), hip circumference (HC) and waist/hip ratio (W/H ratio) improvement was observed after 12 months (p < 0.05, respectively) in both groups. Significant systolic blood pressure (SBP) and diastolic blood pressure (DBP) improvement (p < 0.05) was present in orlistat group after 12 months. Lipid profile [total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C) and triglycerides] reduction (p < 0.05, respectively) was observed in orlistat group and triglyceride reduction (p < 0.05) in sibutramine group after 12 months. No significant change was observed in sibutramine group during the study. No significant HR variation was obtained during the study in both groups. Of the 109 patients who completed the study, 48.1% of patients in the orlistat group and 17.5% of patients in the sibutramine group had side effects (p < 0.05 vs. orlistat group). Side-effect profiles were different in the two treatment groups. All orlistat side effects were gastrointestinal events. Sibutramine caused an increase in blood pressure (both SBP and DBP) in two patients, but it has been controlled by antihypertensive treatment. The vitamin changes were small and all mean vitamin and beta-carotene values stayed within reference ranges. No patients required vitamin supplementation. CONCLUSIONS: Both orlistat and sibutramine are effective on anthropometric variables during the 12-month treatment; in our sample, orlistat has been associated to a mild reduction in blood pressure, while sibutramine assumption has not be associated to any cardiovascular effect and was generically better tolerated than orlistat.

Apolipoprotein(a) size polymorphism is associated with coronary heart disease in polygenic hypercholesterolemia.

BACKGROUND AND AIM: In addition to high serum cholesterol levels, various cardiovascular risk factors may be involved in the development of coronary heart disease (CHD) in hypercholesterolemic subjects. As the levels of lipoprotein(a) [Lp(a)], an important and independent cardiovascular risk factor, are high in polygenic hypercholesterolemia (PH), we investigated plasma Lp(a) levels and apolipoprotein(a) [apo(a)] phenotypes in relation to occurrence of CHD events in PH patients. METHODS AND RESULTS: Lp(a) levels and apo(a) isoforms were determined in 191 PH patients, 83 normocholesterolemic subjects with CHD, and 94 normocholesterolemic controls without CHD. Lp(a) levels were similar in the hypercholesterolemic subjects with (n=100) or without CHD (n=91): 21.4 (range 6.6-59.23) vs 18.5 (range 5.25-57.25) mg/dL (p=NS). Low molecular weight apo(a) isoforms were more prevalent (55%) in the PH patients with CHD, whereas high molecular weight apo(a) isoforms were more prevalent (62.6%) in those without CHD: this difference was significant (p<0.05). A stepwise multiple-discriminant analysis made in order to determine the independence of common cardiovascular risk factors, Lp(a) levels and low molecular weight apo(a) isoforms in predicting CHD among hypercholesterolemic subjects showed that the presence of a positive family history of CHD, smoking, age, and the presence of at least one apo(a) isoform of low molecular weight were independently associated with CHD. CONCLUSIONS: Despite high Lp(a) levels, our findings do not support the hypothesis that Lp(a) plays an independent role in determining clinical CHD in PH subjects. However, the presence of at least one low molecular weight apo(a) isoform is an independent genetic predictor of CHD in hypercholesterolemic subjects. Together with other cardiovascular risk factors, apo(a) phenotypes should be assessed to evaluate the overall CHD risk status of all subjects with high serum cholesterol levels.