Effects of gemfibrozil on insulin sensitivity and on haemostatic variables in hypertriglyceridemic patients.

In order to assess the efficacy of gemfibrozil on lipid and haemostatic parameters in patients with plurimetabolic syndrome, a multicenter double-blind placebo controlled, parallel study was carried out in 56 patients with primary hypertriglyceridemia and glucose intolerance. These patients had elevated PAI activity and antigen and t-PA antigen levels at rest and after venous occlusion. Gemfibrozil reduced plasma triglyceride levels (P<0.001), whereas it increased free fatty acids (P<0.05) and high density lipoprotein cholesterol levels (P<0.05). In those patients reaching normalization of plasma triglyceride levels (triglyceride reduction > or =50%) (n=15), insulin levels (P<0.05) as well as the insulin resistance index were reduced by gemfibrozil treatment, suggesting an improvement of the insulin resistance index in this patient subgroup. Gemfibrozil treatment did not affect plasma fibrinolysis or fibrinogen levels, despite marked reduction of plasma triglycerides and improvement of the insulin sensitivity associated with triglyceride normalization.

Fibrinolytic response in subjects with hypertriglyceridemia and low HDL cholesterol.

The combination of hypertriglyceridemia and low high-density lipoprotein cholesterol (HDL-C) appears to be an excessively high risk factor for coronary artery disease (CAD). In the Helsinki study, both coronary events and mortality were decreased by gemfibrozil, especially in subjects with low HDL-C and high triglycerides (TG). On the other hand, it is known that high levels of TG can be associated with high levels of circulating plasminogen activator inhibitor (PAI), which is also a possible risk factor for CAD. The aim of the present study was to see: 1) whether the combination of low HDL-C and high TG is associated with a more impaired fibrinolytic response than in either isolated condition, and 2) whether gemfibrozil administration can improve fibrinolysis in patients with both high TG and low HDL-C. Twelve non-obese, non-diabetic subjects (eight men, four women; mean age 55 +/- 13 yrs) with low HDL-C (< 35 mg/dL men; < 45 mg/dL women) and high TG (mean 253.6 +/- 42.6 mg/dL) entered the study (Group A). Additionally fourteen comparable subjects with normal HDL-C were also investigated (Group B), plus 12 comparable subjects with isolated low HDL-C (Group C). Ten healthy people served as the control group. The following plasma fibrinolytic parameters were measured: tissue plasminogen activator antigen, PAI antigen and activity, euglobulin fibrinolytic activity (EFA) on fibrin plates, plasminogen and alpha-2-antiplasmin activities. All except the latter two values were also measured after venous occlusion (vo). In baseline conditions, patients in Groups A and B had higher EFA values before vo and higher PAI-1 antigen and alpha-2-antiplasmin levels after vo than those of controls or the subjects in Group C. The relationship between PAI antigen and PAI activity and TG was not confirmed in our population (n = 48). We also saw no interference due to HDL-C, while there was a significant relationship between EFA before vo and both TG and cholesterol. After gemfibrozil treatment (600 mg bid for 12 weeks), the lipid profiles of subjects with high TG and low HDL-C were significantly improved. There was also a slight reduction of PAI activity after vo, while the PAI-1 antigen had decreased significantly from baseline after vo (56.3 +/- 13 ng/mL before vo; 48.4 +/- 21 ng/mL after vo; P = 0.04). The higher risk of CAD in patients with low HDL-C and high TG might be in part related to impairment of fibrinolysis, which occurs in patients with isolated high TG. The close relationship existing between both TG and cholesterol levels and fibrinolytic activity confirm the key role of this latter process in the development of CAD.

Improvement of fibrinolysis and plasma lipoprotein levels induced by gemfibrozil in hypertriglyceridemia.

A randomized double-blind study was carried out with gemfibrozil (600 mg b.i.d.) vs placebo in 20 patients (twelve males and eight females, age 52 +/- 3 years, BMI 24.2 +/- 0.4) suffering from primary hypertriglyceridemia (Fredrickson's type IV). Each group was treated for a 12 week period with gemfibrozil (n = 10) or placebo (n = 10) patients) in a double-blind fashion. Total cholesterol, HDL-cholesterol (HDL-C) and its subfractions (HDL2-C and HDL3-C), blood glucose, Apolipoproteins A1 and B, fibrinogen, plasminogen, factor VII, t-PA:Ag and PAI activity pre- and post-venous occlusion (VO) were determined. In the gemfibrozil-treated group a significant decrease of total cholesterol and triglycerides and a significant increase of HDL-C and HDL2-C were found. During gemfibrozil treatment a significant reduction of factor VII, fibrinogen and plasminogen levels was also observed. After 12 weeks of treatment in the gemfibrozil group the release of t-PA:Ag in response to venous occlusion was significantly higher and plasma PAI activity was significantly lower than in placebo group. Moreover positive correlations between HDL cholesterol and t-PA:Ag post-VO (r = 0.56, P < 0.01) and between HDL2-C cholesterol and t-PA:Ag post-VO (r = 0.59, P < 0.01) and a negative correlation between triglycerides and t-PA:Ag post-VO (r = -0.65, P < 0.01) were found. The data obtained suggest that gemfibrozil, in addition to the well established lipid-regulating effect, appears to have a positive role in the regulation of reverse cholesterol transport and fibrinolytic system.

The effect of gemfibrozil on lipid profile and glucose metabolism in hypertriglyceridaemic well-controlled non-insulin-dependent diabetic patients. For the Gemfibrozil Study Group.

We assessed the efficacy of gemfibrozil therapy on lipid profile and glucose metabolism in a large cohort of (type 2) non-insulin-dependent diabetic patients. We enrolled 217 type 2 diabetic patients with plasma triglyceride concentrations equal to or above 2 mmol/l: 110 were randomized to gemfibrozil (600 mg twice daily) and 107 to placebo treatment in a double blind fashion. Each treatment was followed for 20 weeks. To assess postprandial glucose metabolism and insulin secretion, at time 0 and 20 weeks, a standard meal containing 12.5 g of proteins, 40.1 g of carbohydrate, 10 g of lipids was given. No differences in demographic characteristics were observed between patients randomized either to gemfibrozil or to placebo therapy. No differences were observed in total cholesterol and LDL-cholesterol concentration changes between the baseline observations and week 20 of both treatments. At variance, both treatments significantly increased HDL cholesterol. Gemfibrozil treatment significantly decreased plasma triglyceride concentration from 316+/-84 to 214+/-82 mg/dl (P < 0.001), whereas with placebo triglyceride levels increased from 318 + 93 to 380 + 217 mg/dl. No changes were observed in non-esterified fatty acid concentrations or in fasting plasma glucose concentrations, in HbA(1C) values, insulin and C-peptide concentrations. Gemfibrozil treatment: 1) significantly reduces circulating triglyceride concentration; 2) does not significantly affect cholesterol concentration; 3) does not worsen glucose metabolism.

Treatment of heterozygous familial hypercholesterolemia: atorvastatin vs simvastatin.

BACKGROUND AND AIM: This study compares the cholesterol-lowering efficacy of atorvastatin and simvastatin in attainment of the National Cholesterol Education Program (NCEP) guidelines LDL-cholesterol (LDL-C) goal in patients with heterozygous familial hypercholesterolemia (HFH). The association of atorvastatin with significant changes of blood fibrinogen and other coagulative variables was also compared with that of simvastatin. METHODS AND RESULTS: In a 24-week study, 26 HFH patients (16 men, 10 women, mean age 55.1 +/- 11.3) were randomly assigned to receive atorvastatin or simvastatin. The initial daily dose of 10 mg was progressively raised to 20, 40 and 80 mg in patients who had not reached the NCEP LDL-C goal. Significant reductions of total and LDL-C (p < 0.001), triglycerides (p < 0.005) and apoB100 (p < 0.001) were observed in both groups. Atorvastatin caused greater reductions in total cholesterol (-42% vs -30%) (p < 0.001) and LDL-C (-50% vs -37%) (p < 0.01). Three patients treated with Atorvastatin (23%) and none of those treated with simvastatin reached the NCEP LDL-C goal at the end of the study. No significant departures from the fibrinogen and coagulative variable baselines were observed. CONCLUSIONS: Atorvastatin has greater cholesterol-lowering efficacy than simvastatin in HFH.

Post-prandial effects of gemfibrozil vs simvastatin in hypercholesterolemic subjects with borderline hypertriglyceridemia.

BACKGROUND AND AIM: Impaired triglyceride-rich lipoprotein metabolism is most probably related to an enhanced cardiovascular risk, and may be associated with a pro-coagulant state. A double-blind, randomized study was undertaken to evaluate two widely utilized hypolipidemic drugs in the post-prandial phase and their impact on lipid, coagulation and fibrinolytic parameters. METHODS AND RESULTS: Thirty middle-aged men selected according to their low density lipoprotein-cholesterol (LDL-C) > or = 160 and < or = 240 mg/dl and borderline hypertriglyceridemia (110-220 mg/dl) after at least one month of a lipid-lowering diet received gemfibrozil (600 mg bid) or simvastatin (20 mg qd) and the corresponding placebo. On enrollment and after 2 months of drug treatment, they were tested with a standard oral fat load (OFL) (35 g fat/m2 body surface). On both occasions plasma total-cholesterol, LDL-C, HDL-C, triglycerides, lipoprotein[a] (Lp[a]), tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), antithrombin-III (AT-III), plasminogen and fibrinogen were determined just before the meal (t0) and at times 2 hours, 4 h, 6 h, 8 h after it (t2-t8). A two-factor (time and visit) multivariate analysis for repeated measurements was performed to evaluate the data. Total cholesterol, and LDL-C were significantly diminished 2 months after both gemfibrozil and simvastatin, the latter being more active. Plasma triglycerides showed a marked reduction with gemfibrozil at all times, while simvastatin regimen yielded only minor modifications. HDL-C was only slightly increased by simvastatin; Lp[a] plasma levels were almost unaffected. Small fibrinogen (t0, t2, t6, t8), PAI-1 (t6) and AT III (t0-t8) increases were observed after gemfibrozil, while simvastatin did not significantly modify these parameters. CONCLUSIONS: In the post-prandial phase, gemfibrozil and simvastatin induce different metabolic effects that beneficially influence the lipid pattern, whereas fibrinolytic and coagulative parameters display minor variations of undetermined significance.

Gemfibrozil improves insulin sensitivity and flow-mediated vasodilatation in type 2 diabetic patients.

BACKGROUND: Endothelial dysfunction is an early feature of atherosclerosis. The relationship between insulin action and hypertriglyceridaemia on endothelial function is still debated. MATERIALS AND METHODS: This study was designed to determine the effect of a 3 month treatment with Gemfibrozil (GF) on flow-mediated vasodilatation and insulin sensitivity. Ten type 2 diabetic patients were randomised in crossover, double blind fashion, either to GF, 600 mg b.i.d. or placebo, for 12 weeks. Lipid profile, low-density lipoprotein (LDL) distribution and flotation properties, insulin action and flow-mediated vasodilatation (FMD) by brachial artery ultrasound, were assessed. RESULTS: GF decreased serum triglyceride (TG) concentration with an absolute difference of 1.79 +/- 1.28 mmol L-1 (P < 0.0016) between active treatment and placebo, and significantly increased serum high-density lipoprotein (HDL) cholesterol (P = 0.0233). No differences were observed in total, intermediate-density lipoproteins (IDL), LDL cholesterol concentration and LDL peak buoyancy between treatments. GF also improved SI, an index of insulin action (P = 0.005). The FMD was 7 +/- 3% in the baseline condition, 7 +/- 2% during placebo and 14 +/- 3% after GF (P < 0.006). CONCLUSIONS: GF treatment improves both insulin action and flow-mediated vasodilatation in type 2 diabetic patients. The reduction of TG concentration allows the simultaneous correction of two important components of the metabolic syndrome.