Simvastatin reduces plasma lipid levels and improves insulin action in elderly, non-insulin dependent diabetics

Comparative effectiveness of statins on non-high density lipoprotein cholesterol in people with diabetes and at risk of cardiovascular disease: systematic review and network meta-analysis

OBJECTIVE

To compare the efficacy of different statin treatments by intensity on levels of non-high density lipoprotein cholesterol (non-HDL-C) for the prevention of cardiovascular disease in people with diabetes.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Medline, Cochrane Central Register of Controlled Trials, and Embase from inception to 1 December 2021.

REVIEW METHODS

Randomised controlled trials comparing different types and intensities of statins, including placebo, in adults with type 1 or type 2 diabetes mellitus were included. The primary outcome was changes in levels of non-HDL-C, calculated from measures of total cholesterol and HDL-C. Secondary outcomes were changes in levels of low density lipoprotein cholesterol (LDL-C) and total cholesterol, three point major cardiovascular events (non-fatal stroke, non-fatal myocardial infarction, and death related to cardiovascular disease), and discontinuations because of adverse events. A bayesian network meta-analysis of statin intensity (low, moderate, or high) with random effects evaluated the treatment effect on non-HDL-C by mean differences and 95% credible intervals. Subgroup analysis of patients at greater risk of major cardiovascular events was compared with patients at low or moderate risk. The confidence in network meta-analysis (CINeMA) framework was applied to determine the certainty of evidence.

RESULTS

In 42 randomised controlled trials involving 20 193 adults, 11 698 were included in the meta-analysis. Compared with placebo, the greatest reductions in levels of non-HDL-C were seen with rosuvastatin at high (-2.31 mmol/L, 95% credible interval -3.39 to -1.21) and moderate (-2.27, -3.00 to -1.49) intensities, and simvastatin (-2.26, -2.99 to -1.51) and atorvastatin (-2.20, -2.69 to -1.70) at high intensity. Atorvastatin and simvastatin at any intensity and pravastatin at low intensity were also effective in reducing levels of non-HDL-C. In 4670 patients at greater risk of a major cardiovascular events, atorvastatin at high intensity showed the largest reduction in levels of non-HDL-C (-1.98, -4.16 to 0.26, surface under the cumulative ranking curve 64%). Simvastatin (-1.93, -2.63 to -1.21) and rosuvastatin (-1.76, -2.37 to -1.15) at high intensity were the most effective treatment options for reducing LDL-C. Significant reductions in non-fatal myocardial infarction were found for atorvastatin at moderate intensity compared with placebo (relative risk=0.57, confidence interval 0.43 to 0.76, n=4 studies). No significant differences were found for discontinuations, non-fatal stroke, and cardiovascular deaths.

CONCLUSIONS

This network meta-analysis indicated that rosuvastatin, at moderate and high intensity doses, and simvastatin and atorvastatin, at high intensity doses, were most effective at moderately reducing levels of non-HDL-C in patients with diabetes. Given the potential improvement in accuracy in predicting cardiovascular disease when reduction in levels of non-HDL-C is used as the primary target, these findings provide guidance on which statin types and intensities are most effective by reducing non-HDL-C in patients with diabetes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021258819.

Dual Effect of Rosuvastatin on Glucose Homeostasis Through Improved Insulin Sensitivity and Reduced Insulin Secretion

Statins are beneficial in the treatment of cardiovascular disease (CVD), but these lipid-lowering drugs are associated with increased incidence of new on-set diabetes. The cellular mechanisms behind the development of diabetes by statins are elusive. Here we have treated mice on normal diet (ND) and high fat diet (HFD) with rosuvastatin. Under ND rosuvastatin lowered blood glucose through improved insulin sensitivity and increased glucose uptake in adipose tissue. In vitro rosuvastatin reduced insulin secretion and insulin content in islets. In the beta cell Ca^2 + signaling was impaired and the density of granules at the plasma membrane was increased by rosuvastatin treatment. HFD mice developed insulin resistance and increased insulin secretion prior to administration of rosuvastatin. Treatment with rosuvastatin decreased the compensatory insulin secretion and increased glucose uptake. In conclusion, our data shows dual effects on glucose homeostasis by rosuvastatin where insulin sensitivity is improved, but beta cell function is impaired.

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Rosuvastatin lowered blood glucose in vivo most likely due to improved glucose uptake.

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Rosuvastatin reduced insulin content and impaired Ca^2 + signaling in beta cells leading to reduced insulin secretion.

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Dual effects of rosuvastatin in HFD mice though decreased compensatory insulin secretion and increased glucose uptake.

Statins are a group of drugs used to lower blood cholesterol in individuals with a risk of developing cardiovascular disease. It has been shown in several studies that statins increase the risk of developing type 2 diabetes. This increased risk has not yet been explained. We have investigated the effect of rosuvastatin on blood glucose regulation in mice. We found that rosuvastatin has a beneficial effect on glucose uptake in muscles which results in lowered blood glucose. However, in the insulin producing beta cells rosuvastatin altered normal cell function something that might increase the risk of developing type 2 diabetes.

Statin therapy and plasma free fatty acids: a systematic review and meta-analysis of controlled clinical trials

AIM

The aim of this meta-analysis was to evaluate the effect of statin therapy on plasma FFA concentrations in a systematic review and meta-analysis of controlled clinical trials.

METHODS

PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases were searched (from inception to February 16 2015) to identify controlled trials evaluating the impact of statins on plasma FFA concentrations. A systematic assessment of bias in the included studies was performed using the Cochrane criteria. A random effects model and generic inverse variance method were used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. Random effects meta-regression was performed using unrestricted maximum likelihood method to evaluate the impact of potential moderators.

RESULTS

Meta-analysis of data from 14 treatment arms indicated a significant reduction in plasma FFA concentrations following treatment with statins (weighted mean difference (WMD) -19.42%, 95% CI -23.19, --15.64, P < 0.001). Subgroup analysis confirmed the significance of the effect with both atorvastatin (WMD -20.56%, 95% CI -24.51, -16.61, P < 0.01) and simvastatin (WMD -18.05%, 95% CI -28.12, -7.99, P < 0.001). Changes in plasma FFA concentrations were independent of treatment duration (slope -0.10, 95% CI -0.30, 0.11, P = 0.354) and magnitude of reduction in plasma low density lipoprotein cholesterol concentrations (slope 0.55, 95% CI -0.17, 1.27, P = 0.133) by statins.

CONCLUSIONS

The results of the present study suggest that statin therapy may lower plasma FFA concentrations. The cardiovascular and metabolic significance of this finding requires further investigation.

The peroxisome proliferator-activated receptor alpha agonist fenofibrate has no effect on insulin sensitivity compared to atorvastatin in type 2 diabetes mellitus; a randomised, double-blind controlled trial

AIMS

Assess insulin sensitivity after treatment with a selective PPAR-alpha agonist compared to an HMG CoA reductase inhibitor in human subjects with type 2 diabetes mellitus.

METHODS

Thirteen subjects with Type 2 diabetes mellitus were studied in a double-blind crossover design with 4-week placebo run-in and washout and 12-week treatment periods, randomised to micronised fenofibrate 267 mg or atorvastatin 10mg daily followed by the alternate drug in the second period. Insulin resistance was measured using the isoglycaemic hyperinsulinaemic clamp method with isotope dilution.

RESULTS

Weight, physical activity and other medications did not change. Total cholesterol (mean +/- standard error) was 4.60+/-0.21 versus 3.9+/-0.22 mmol/L after fenofibrate and atorvastatin respectively, p<0.05. LDL was 2.70+/-0.19 versus 1.95+/-0.23 mmol/L, p<0.05 and triglyceride 1.64+/-0.23 versus 1.84+/-0.26 mmol/L, p<0.05. Insulin-stimulated whole-body glucose disposal (35.4+/-3.1 versus 33.2+/-3.0 μmol/kg/min) and nadir endogenous glucose production (6.2+/-1.4 versus 7.0+/-1.1 μmol/kg/min) revealed no significant differences in effects of the treatments.

CONCLUSIONS

In human subjects with Type 2 diabetes mellitus there were characteristic differences in lipid profile changes but no difference in insulin sensitivity after treatment with micronised fenofibrate compared to atorvastatin. This study finds no evidence of increased insulin sensitivity using this selective PPAR-alpha agonist over a commonly used statin at these doses.

Effects of atorvastatin 10 mg/d on insulin resistance: A 12-week, open-label study in hyperlipidemic patients

BACKGROUND

In addition to their cholesterol-lowering effects, hydroxymethylglutaryl coenzyme A reductase inhibitors ("statins") might have pleiotropic, nonlipid effects. Insulin resistance syndrome is known to increase the risk for cardiovascular disease. However, the effects of statins on insulin resistance are a subject of controversy.

OBJECTIVE

We aimed to investigate the effects of atorvastatin on insulin resistance in hyperlipidemic patients.

METHODS

This 12-week, prospective, nonrandomized, open-label study was conducted at the outpatient cardiology clinic, Ege University Medical School, Bornova-Izmir, Turkey. Hyperlipidemic patients aged ≥18 years with insulin resistance and no other components of the metabolic syndrome were included in the study. Atorvastatin 10 mg QD (after the evening meal) was administered by mouth (tablet) over a 12-week period. At baseline and after 12 weeks of treatment, insulin sensitivity was assessed using homeostasis model assessment (HOMA) index methodology. Serum lipid parameters and fasting levels of plasma glucose and insulin (FPG and FPI, respectively) were measured at the same 2 time points. The tolerability of atorvastatin was assessed using laboratory analysis and physical examination, including vital sign measurements.

RESULTS

Fifteen white patients (9 women, 6 men; mean [SD] age, 52 [8] years) participated in the study. No significant changes in HOMA index were found (mean [SD], 3.1 [1.5] vs 3.2 [1.9]). The lipid profile was improved significantly at 12 weeks compared with baseline (mean [SD] low-density lipoprotein cholesterol, 173.2 [21.3] vs 110.8 [43.6] mg/dL; total cholesterol, 270.9 [21.5] vs 201.2 [46.7] mg/dL; and triglycerides, 269.5 [46.3] vs 205.5 [49.3] mg/dL; all, P < 0.001). No significant change in mean (SD) plasma high-density lipoprotein cholesterol level (45.5 [6.6] vs 43.7 [8.1] mg/dL) was found. In addition, no significant changes in FPG (85.3 [12.71 vs 84.8 [10.4] mg/dL), or FPI (13.5 [9.7] vs 13.9 [10.1] μU/mL) were found. None of the patients required withdrawal of medication due to an adverse event.

CONCLUSION

In this pilot study in hyperlipidemic patients with insulin resistance, 12 weeks of treatment with atorvastatin 10 mg QD was effective in controlling hyperlipidemia but did not reduce the severity of insulin resistance.

Predictors and prevention of diabetic cardiomyopathy

Despite our cognizance that diabetes can enhance the chances of heart failure, causes multiorgan failure,and contributes to morbidity and mortality, it is rapidly increasing menace worldwide. Less attention has been paid to alert prediabetics through determining the comprehensive predictors of diabetic cardiomyopathy (DCM) and ameliorating DCM using novel approaches. DCM is recognized as asymptomatic progressing structural and functional remodeling in the heart of diabetics, in the absence of coronary atherosclerosis and hypertension. The three major stages of DCM are: (1) early stage, where cellular and metabolic changes occur without obvious systolic dysfunction; (2) middle stage, which is characterized by increased apoptosis, a slight increase in left ventricular size, and diastolic dysfunction and where ejection fraction (EF) is <50%; and (3) late stage, which is characterized by alteration in microvasculature compliance, an increase in left ventricular size, and a decrease in cardiac performance leading to heart failure. Recent investigations have revealed that DCM is multifactorial in nature and cellular, molecular, and metabolic perturbations predisposed and contributed to DCM. Differential expression of microRNA (miRNA), signaling molecules involved in glucose metabolism, hyperlipidemia, advanced glycogen end products, cardiac extracellular matrix remodeling, and alteration in survival and differentiation of resident cardiac stem cells are manifested in DCM. A sedentary lifestyle and high fat diet causes obesity and this leads to type 2 diabetes and DCM. However, exercise training improves insulin sensitivity, contractility of cardiomyocytes, and cardiac performance in type 2 diabetes. These findings provide new clues to diagnose and mitigate DCM. This review embodies developments in the field of DCM with the aim of elucidating the future perspectives of predictors and prevention of DCM.

Altered cholesterol homeostasis contributes to enhanced excitotoxicity in Huntington's disease

Recent findings suggest that altered cholesterol homeostasis may contribute to the pathophysiology of Huntington's disease (HD). To understand the underlying mechanisms, here we used a combination of two-photon microscopy, epifluorescence, and biochemical methods to visualize and quantify lipid distribution in cell cultures expressing mutant huntingtin. Such expression promotes lipid imbalance, and cholesterol accumulation in cellular and murine models and in HD-affected human brains. Interestingly, cells expressing mutant huntingtin also showed higher content of ordered domains in their plasma membranes. These findings correlated with high levels of caveolin-1 and glycosphingolipid GM1, two well-defined markers of cholesterol-enriched domains, at the cell surface. In addition, cells expressing mutant huntingtin showed increased localization of NMDA receptors with cholesterol-enriched domains, contributing to increased NMDA receptor susceptibility to excitotoxic insults. Treatment with simvastatin or β-cyclodextrin, two cholesterol-lowering drugs, reduced the content of ordered domains at the cell surface, which in turn, protected cells against NMDA-mediated excitotoxicity. Taken together, our results indicate that mutant huntingtin produces accumulation of cholesterol and alters its cellular distribution that contributes to NMDA-mediated excitotoxicity. Administration of drugs that recover this effect, such as simvastatin could be beneficial for the treatment of HD.

Statin use and the risk of cholecystectomy in women

BACKGROUND & AIMS

Statins can reduce biliary cholesterol secretion independently of their ability to inhibit cholesterol synthesis. Statins also prevent the formation of gallstones in animal studies, although the effect of statins on human gallstone disease has been controversial.

METHODS

We examined the relationship between the use of statins and the risk of cholecystectomy in a cohort of US women. As part of the prospective Nurses' Health Study, participants biennially reported their history of gallstone disease and whether they had undergone cholecystectomy. Women also reported lifetime use of statins retrospectively in 2000. We conducted a retrospective analysis of statin using data collected in 2000, to define use from 1994 forward, and a prospective analysis for general lipid-lowering drugs from 1994 to 2004.

RESULTS

In the statin analysis we ascertained 2479 cases of cholecystectomy during 305,197 person-years of follow-up evaluation. The multivariate relative risk for current statin users, compared with nonusers, was 0.82 (95% confidence interval, 0.70-0.96). In the analysis of general cholesterol-lowering drugs, we ascertained 3420 cases of cholecystectomy during 511,411 person-years of follow-up evaluation. Compared with nonusers, the multivariate relative risk for current users of general cholesterol-lowering drugs, mostly statins in this cohort, was 0.88 (95% confidence interval, 0.79-0.98).

CONCLUSIONS

Statin use appears to reduce the risk of cholecystectomy in women.

Statin modulates insulin signaling and insulin resistance in liver and muscle of rats fed a high-fat diet

Recent studies have shown that statins might have relevant effects on insulin resistance in animal models and in humans. However, the molecular mechanisms that account for this improvement in insulin sensitivity are not well established. The aim of the present study was to investigate the effect of a statin on insulin sensitivity and insulin signaling in liver and muscle of rats fed on a high-fat diet (HFD) for 4 weeks, treated or not with lovastatin during the last week. Our data show that treatment with lovastatin results in a marked improvement in insulin sensitivity characterized by an increase in glucose disappearance rate during the insulin tolerance test. This increase in insulin sensitivity was associated with an increase in insulin-induced insulin receptor (IR) tyrosine phosphorylation and, in parallel, a decrease in IR serine phosphorylation and association with PTP1B. Our data also show that lovastatin treatment was associated with an increase in insulin-stimulated insulin receptor substrate (IRS) 1/phosphatidylinositol 3-kinase/Akt pathway in the liver and muscle of HFD-fed rats in parallel with a decrease in the inflammatory pathway (c-jun N-terminal kinase and I kappa beta kinase (IKKbeta)/inhibitor of kappaB/nuclear factor kappaB) related to insulin resistance. In summary, statin treatment improves insulin sensitivity in HFD-fed rats by reversing the decrease in the insulin-stimulated IRS-1/phosphatidylinositol 3-kinase/Akt pathway in liver and muscle. The effect of statins on insulin action is further supported by our findings that HFD rats treated with statin show a reduction in IRS-1 serine phosphorylation, I kappa kinase (IKK)/inhibitor of kappaB/nuclear factor kappaB pathway, and c-jun N-terminal kinase activity, associated with an improvement in insulin action. Overall, these results provide important new insight into the mechanism of statin action in insulin sensitivity.

Effect of pravastatin on the development of diabetes and adiponectin production

In the West of Scotland Coronary Prevention Study (WOSCOPS), treatment of hypercholesterolemic men with pravastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, reduced their likelihood to progress to diabetes mellitus by 30%. However, the mechanism of this effect of pravastatin has not been investigated. In the current study, we examined the effect of pravastatin on the development of diabetes in obese diabetic mice, and on the insulin-induced glucose uptake and adiponectin production. Pravastatin treatment attenuated the development of diabetes in db/db and high fat/high sucrose diet-fed C57BL/6J mice. An in vivo glucose transport assay showed that pravastatin upregulated glucose uptake in adipose tissue. Insulin-stimulated glucose uptake was enhanced in primary adipocytes isolated from pravastatin-treated mice. Pravastatin treatment increased adiponectin production in 3T3-L1 adipocytes. Plasma adiponectin levels were significantly increased in pravastatin-treated mice. Analyses of plasma samples from the WOSCOPS biobank indicated a significant increase of plasma adiponectin levels with pravastatin treatment (placebo -0.28+/-0.34 microg/ml versus pravastatin +1.47+/-0.33 microg/ml, p=0.0003). Taken together, our findings suggest that pravastatin may have beneficial effects on adipose tissue, which may partly explain the reduction of the development of diabetes by pravastatin treatment.

Effect of rosuvastatin on insulin sensitivity in patients with familial combined hyperlipidaemia

BACKGROUND

By influencing the mevalonate pathway, statins may have multiple effects besides lipid lowering. This study was designed to evaluate the effect of rosuvastatin on serum lipids and insulin sensitivity in nondiabetic subjects with familial combined hyperlipidaemia (FCH), a population characterized by decreased insulin sensitivity.

METHODS

In a double-blind randomized crossover study, 18 subjects with FCH (without evident cardiovascular disease, mean age 54 +/- 7 years) were randomized to rosuvastatin 40 mg day(-1) or placebo for 12 weeks. Blood samples were taken at baseline and after 4, 8 and 12 weeks of both treatment periods. Insulin sensitivity was determined with euglycaemic-hyperinsulinaemic clamp after 12 weeks of both treatment periods.

RESULTS

Serum lipids and lipoproteins improved significantly. Mean total cholesterol after the rosuvastatin treatment period was 44% lower compared to the placebo treatment period (triglycerides -28%; LDL-c -50%; VLDL-c -56%, VLDL-TG -39%) and both parameters of low-grade inflammation (as measured by hsCRP, -16%) and oxidative stress (as measured by plasma-oxLDL, -55%) decreased markedly after rosuvastatin therapy as compared to placebo. However, the insulin sensitivity index was unchanged (41.7 +/- 17.4 vs. 40.6 +/- 11.1 L kg(-1) min(-1), placebo vs. rosuvastatin, P = 0.71).

CONCLUSION

Despite marked improvements in lipid and lipoprotein values, low-grade inflammation and oxidative stress, a relatively high dose of rosuvastatin did not change insulin sensitivity in subjects with FCH.

Atorvastatin induces insulin sensitization in Zucker lean and fatty rats

BACKGROUND

The 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors ('statins') have been implicated in preventing new onset type 2 diabetes, whereas the mechanism of this effect is not known. We investigated the effects of an HMG-CoA reductase inhibitor, atorvastatin, on insulin sensitization in Zucker lean and fatty rats.

METHODS AND RESULTS

In vivo studies of insulin sensitization were performed in chow fed Zucker lean and fatty rats treated with atorvastatin 50mg/kg/day (ATORVA_50) and results were compared to Zucker lean and fatty rats treated with drug vehicle only (CONT). Additional Zucker lean rats were treated with an intermediate dose of atorvastatin 25mg/kg/day (ATORVA_25). Treatment with atorvastatin resulted in a dose-dependent improvement in whole body insulin sensitivity in both lean and fatty rats, with an approximately two-fold increase in glucose infusion rate and glucose disposal (Rd) in ATORVA_50 versus CONT (p<0.01). Atorvastatin 50mg/kg/day resulted in an increase in 2-deoxyglucose (2-DOG) uptake by skeletal muscles (approximately two-fold increase in 2-DOG uptake in quadriceps (p=0.06) and gastrocnemius (p<0.01)) in lean Zucker rats. Insulin-stimulated phosphorylation of Akt/PKB was significantly increased in skeletal muscle of ATORVA_50 versus CONT in both lean and fatty rats.

CONCLUSION

Atorvastatin induces insulin sensitization in Zucker lean and fatty rats. This may be a clinically important pleiotropic effect if confirmed in insulin resistant humans.

Pravastatin does not affect insulin sensitivity and adipocytokines levels in healthy nondiabetic patients

BACKGROUND

The effect of statins on insulin resistance is controversial and poorly studied in nondiabetic subjects. In addition, the effect of statins on leptin and adiponectin has never been studied.

METHODS

Forty healthy nondiabetic volunteers (22 men and 18 women) aged 28 to 72 were randomized either to placebo or pravastatin 40 mg daily for a 12-week period. Insulin resistance, assessed using the Quantitative Insulin Sensitivity Check Index (QUICKI), as well as serum leptin and adiponectin levels, was measured at baseline and at the end of therapy.

RESULTS

Pravastatin treatment decreased total cholesterol, low-density lipoprotein cholesterol, and triglycerides levels by 24%, 32%, and 14%, respectively ( P < .05 for all), but did not affect glucose and insulin levels, the (QUICKI) index, and adiponectin and leptin levels. When stratification was performed according to QUICKI index or sex, no significant differences were observed in the prevalues and postvalues of leptin, adiponectin, or QUICKI index in the pravastatin group. Adiponectin, leptin, and QUICKI index were statistically higher in women than in men ( P < .001 for both variables). Adiponectin was negatively correlated with body mass index (BMI; r = -0.39, P < .05) and positively correlated with the QUICKI index ( r = 0.54, P < .001) and with high-density lipoprotein cholesterol ( r = 0.50, P < .01). The relation between adiponectin and QUICKI index remained significant after adjustment for sex and BMI ( P = .005 and P = .007, respectively). Leptin was only related to BMI ( r = 0.57, P < .001) and to sex ( P < .001) with no significant correlations with lipid parameters or QUICKI index. Both sex and BMI are independent predictors of leptin ( P < .001 and P < .001).

CONCLUSION

A 12-week treatment with pravastatin 40 mg/d does not change the QUICKI index and leptin and adiponectin levels in healthy volunteers. In addition, our results emphasize the importance of sex and BMI in the determination of both adiponectin and leptin. Adiponectin was also related to QUICKI index, whereas this relation was not found with leptin.

No effect of simvastatin treatment on insulin sensitivity in patients with primary hypercholesterolemia

OBJECTIVE

Statins, in addition to cholesterol lowering, have nonlipid effects on formation and progression of atheromatous plaque. Insulin resistance and hyperinsulinemia may have detrimental influences on the arterial wall. Statins (may also) inhibit insulin signal transferring in vascular smooth cell cultures. However, their effect on insulin sensitivity remains controversial. Therefore, we decided to investigate the effect of simvastatin on insulin sensitivity in hypercholesterolemic patients.

PATIENTS AND METHODS

Eighteen patients with primary hypercholesterolemia were divided into simvastatin group (n = 9; 4 females, 5 males; BMI 30.6 +/- 4 kg/m2; mean ages 57 +/- 6 years) and placebo group (n = 9; 4 females, 5 males; BMI 28 +/- 2.9 kg/m2; mean ages 49 +/- 10 years). Simvastatin (20 mg/day) or placebo were given for 2 months. Total and HDL cholesterol were measured and LDL cholesterol was calculated by Friedewald formula. Insulin sensitivity was determined by using euglycemic hyperinsulinemic clamp technique [40 microU/m2/min insulin infusion rate; glucose disposal rate (M)= mg/kg/min] before and after treatment.

RESULTS

Plasma levels of total, LDL and HDL cholesterol decreased significantly in simvastatin group after treatment (p = 0.000, p = 0.000, and p = 0.048, respectively). Plasma levels of total cholesterol decreased significantly (p = 0.032), whereas LDL and HDL levels remained unchanged in placebo group. M value (mg/kg/min) decreased insignificantly in simvastatin group (4.32 +/- 1.57 vs. 3.71 +/- 1.91) and increased in placebo group (3.55 +/- 1.91 vs. 3.95 +/- 0.95).

CONCLUSION

Short-term simvastatin treatment did not affect insulin sensitivity determined by "gold standard" euglycemic hyperinsulinemic clamp method in hypercholesterolemic patients in this research. Further studies with simvastatin using higher doses and longer duration should be performed.

Cerivastatin improves insulin sensitivity and insulin secretion in early-state obese type 2 diabetes

In a double-blind, placebo-controlled, randomized crossover study, 15 stable mild hyperglycemic patients without treatment and with features of metabolic syndrome were treated with cerivastatin (0.4 mg/day) or placebo for 3 months. The insulin sensitivity index during the euglycemic-hyperinsulinemic clamp (EHC; 5.4 mmol/l; 80 mU x m(-2) x min(-1)) was increased by cerivastatin treatment (66.39 +/- 3.9 nmol x lean body mass [LBM](-1) x min(-1) x pmol(-1) x l(-1)) as compared with placebo (58.37 +/- 3.69 nmol x LBM(-1) x min(-1) x pmol(-1) x l(- 1); P < 0.01) by 13.7%. Glucose oxidation during EHC was significantly higher with statin treatment (16.1 +/- 1.37 micromol x LBM(-1) x min(-1)) as compared with placebo (14.58 +/- 1.48 micromol x LBM(-1) x min(-1); P < 0.05). During hyperinsulinemia (approximately 800 pmol/l) in EHC steady-state, lipid oxidation was significantly decreased and respiratory quotient was significantly increased with statin treatment (0.33 +/- 0.05 mg x LBM(-1) x min(- 1), 0.94 +/- 0.01) as compared with placebo (0.48 +/- 0.06 mg x LBM(-1) x min(-1), 0.91 +/- 0.01; P < 0.01 and P < 0.05, respectively). During statin treatment, the first-phase insulin response increased from 2.07 +/- 0.28 to 2.82 +/- 0.38 pmol x l(-1) x pmol(-1) (P < 0.05). The second phase of insulin responses examined by C-peptide and insulin levels averaged during the hyperglycemic clamp (20 mmol/l) was unchanged. In conclusion, this study demonstrates that 0.4 mg cerivastatin therapy improves first-phase insulin secretion and increases insulin-mediated glucose uptake and respiratory quotient in the early state of obese type 2 diabetes.

Treating dyslipidaemia in non-insulin-dependent diabetes mellitus -- a special reference to statins

Patients with non-insulin-dependent diabetes (NIDDM) have an increased incidence of ischaemic heart disease (IHD) when compared with nondiabetic subjects. In addition, they have a worse prognosis after their first myocardial infarction (MI). According to the recent USA recommendations, the threshold for initiation of dietary intervention in diabetic subjects is an LDL greater than 2.6 mmol/l, with the goal to achieve levels less than 2.6 mmol/l (100 mg/dl). This is also the threshold for initiation and treatment goal for pharmacological intervention in diabetic subjects, unless they are completely free of IHD, peripheral vascular disease or cerebrovascular disease and have no other IHD risk factors. In the latter circumstances, the threshold for treatment is an LDL greater than 3.38 mmol/l (130 mg/dl), with the goal to achieve levels less than 3.38 mmol/l. The HMG-CoA reductase inhibitors (statins) can improve the lipid profile effectively and safely in NIDDM. Results from post hoc analyses of diabetic subgroups in the large intervention trials suggest that some statins significantly reduce the risk for IHD-related mortality/morbidity. However, because these results are derived from secondary prevention trials, we cannot be sure if these benefits apply to all diabetic subjects or only to those who already have IHD. Nevertheless, it seems logical to assume that this benefit also applies to NIDDM patients who do not have IHD because they share a similar vascular risk as nondiabetic subjects who have IHD. Intervention trials using statins and fibrates, alone or in combination, in NIDDM are under way. In a few years these trials will provide definitive end-point-based evidence in this high-risk group of patients.

Diabetes: statins, fibrates, or both?

Cardiovascular disease is the leading cause of mortality in patients with type 2 diabetes. Among the many factors that are involved in the pathogenesis of atherosclerosis in diabetic patients, dyslipidemia plays a major role. It is characterized by an increase in triglycerides, a decrease in high-density lipoprotein cholesterol and normal or mildly elevated low-density lipoprotein cholesterol. The management of patients with diabetic dyslipidemia is difficult because we lack studies specifically designed for diabetic patients. Thus, strategy has to rely on post hoc analyses of landmark intervention trials, which usually include only a small number of diabetic patients, or on rare trials enrolling small cohorts of diabetic patients. When lifestyle changes fail, monotherapy should be tried first with either a statin or a fibrate, depending on triglyceride level. If lipid target values are not reached, a combination therapy can then be initiated, with close follow-up of potential side effects.

Effects of simvastatin and atorvastatin administration on insulin resistance and respiratory quotient in aged dyslipidemic non-insulin dependent diabetic patients

One hundred and ninety-five aged (mean age: 67+/-4.8 years), non-insulin dependent diabetic patients underwent a randomised single-blind study for investigating the effect of statin administration on insulin resistance and respiratory quotient. After 4 weeks run-in period, all patients were randomised in three groups: placebo (n=67), simvastatin (10 mg/day) (n=61) and atorvastatin (5 mg/day) (n=67). Each treatment period lasted 8 weeks. At the beginning, after the run-in and at the end of the study, insulin resistance was assessed by homeostasis model assessment (HOMA) index, while respiratory quotient (Rq) was evaluated by indirect calorimetry. Statins versus placebo significantly lowered plasma total, LDL-, HDL-cholesterol and triglyceride concentrations and improved insulin resistance and Rq and metabolic control. Atorvastatin had a greater effect than simvastatin on plasma triglyceride concentration (-26.3+/-3.1 vs. -19.7+/-2.8%, P<0.03), HOMA index (-13.1+/-0.6 vs. -9.1+/-0.9%, P<0.05), Rq (5.9+/-0.4 vs. 3.1+/-0.5%, P<0.05) and glycosylated haemoglobin (-11.2+/-0.3 vs. -7. 1+/-0.4%, P<0.05). In the whole group of subjects (n=195) and at the end of the study, changes in plasma triglyceride concentrations were significantly correlated with the change in the HOMA index (r=0.44, P<0.001) and age and BMI adjusted-Rq (r=-0.32, P<0.005). Multivariate analyses demonstrated that decline in plasma triglyceride concentration was a significant determinant for explaining the effect of statin on insulin resistance and Rq. In conclusion our study demonstrates that statin administration is useful for controlling dyslipidemia in NIDDM patients and for improving the metabolic control. With regard to this latter aim, atorvastatin seems to be more powerful than simvastatin.

Lack of effect of simvastatin on insulin sensitivity in Type 2 diabetic patients with hypercholesterolaemia: results from a double-blind, randomized, placebo-controlled crossover study

AIMS

To evaluate the effects of simvastatin on serum lipids and insulin sensitivity in Type 2 diabetic patients with hypercholesterolaemia.

METHODS

A double-blind, randomized, placebo-controlled and two-period crossover study. After a 2-month run-in, 19 eligible Type 2 diabetic patients with hypercholesterolaemia were randomized to receive either simvastatin or placebo for 3 months, exchanging their treatment thereafter for another 3 months. Blood samples were taken in month 0 and at monthly intervals to measure serum lipids and indices of glycaemic control. An euglycaemic insulin clamp was performed in months 0, 3 and 6 to assess change of insulin sensitivity. The amount of glucose infused during 90-120 min of the clamp (M), and the mean values of serum insulin during 90-120 min (I) were measured. The M and M/I ratio were used to represent the in vivo insulin sensitivity of the subject.

RESULTS

Simvastatin significantly reduced serum total cholesterol (TC) by 23+/-18% and low density lipoprotein-cholesterol (LDL-C) by 30+/-26%. It did not alter glycaemic control. The M-values and M/I ratios were similar in both groups in each period and no drug effect on insulin sensitivity could be identified.

CONCLUSIONS

Simvastatin significantly reduced the serum TC and LDL-C levels without alteration of insulin sensitivity in Type 2 diabetic patients with hypercholesterolaemia.

Effect of pravastatin on plasma ketone bodies in diabetics with hypercholesterolemia

Hydroxy-3 methylglutaryl coenzyme A (HMG-CoA) is a common intermediate metabolite of cholesterol synthesis and ketone formation in the liver. In order to study the effect of HMG-CoA reductase inhibitor (pravastatin) on ketone formation, changes in the plasma levels of ketone bodies by treatment with pravastatin were studied in 18 non-insulin dependent diabetics with hypercholesterolemia. Body mass index, diabetic control, and plasma free fatty acid levels were not changed during the study, and the plasma levels of cholesterol decreased significantly from 250 +/- 25 to 211 +/- 34 mg/100 ml after 6 months of pravastatin treatment. The plasma levels of acetoacetic acid also significantly decreased from 37.7 +/- 22.6 to 28.4 +/- 13.4 mumol/l, and those of 3-hydroxybutyric acid and total ketone bodies also tended to decrease after pravastatin treatment. These results suggest that pravastatin decreases ketone formation in hepatic mitochondria besides cholesterol synthesis in hepatic microsome.

Short-term safety and efficacy of low-dose simvastatin in elderly patients with hypertensive hypercholesterolemia and fasting hyperinsulinemia

To evaluate the short-term safety and efficacy of low-dose (10 mg) simvastatin in hypercholesterolemic, hypertensive elderly Chinese patients receiving antihypertensive treatment, a randomized, double-blind, placebo-controlled, 3-month trial was conducted. The patients had a total plasma cholesterol level of at least 250 mg/dL and had been, for at least 3 months, consuming a standard lipid-lowering diet (American Heart Association Step 1 Diet). Elderly hypertensive patients (n = 76) were randomized to receive treatment with either placebo (n = 38) or simvastatin (n = 38). The dosage consisted of 10 mg simvastatin daily during the 3-month trial. During that period, in the simvastatin group, plasma levels of total cholesterol and low-density lipoprotein cholesterol decreased significantly (27% and 33%, respectively) compared with those levels in plasma in the placebo group. The plasma levels of high-density lipoprotein cholesterol increased (7%), whereas triglyceride levels slightly decreased (8%). There were no serious side effects, and simvastatin was generally well tolerated. Fasting hyperinsulinemia also improved (-21%) after 3 months of simvastatin therapy. Results of this study confirmed that a low dose (10 mg) of simvastatin daily is a safe and effective method of reducing plasma levels of total and low-density lipoprotein cholesterol in hypercholesterolemic, hypertensive elderly patients receiving concurrent antihypertensive drug therapy, and that it has the additional potential benefit of reducing plasma levels of insulin.

Brain serotonin (5-HT) neuroendocrine function in patients taking cholesterol-lowering drugs

Brain serotonin (5-HT) neuroendocrine function, plasma tryptophan, and platelet 5-HT content were examined in 20 patients treated in a lipid clinic for hypercholesterolaemia with combined drug and diet therapy and in 20 healthy matched controls. Treatment had produced a substantial decrease in total cholesterol concentrations in the patients, but they still had higher cholesterol and triglyceride levels than control subjects. The patients were somewhat more depressed than controls but did not differ from them in degree of hostility, free or total plasma tryptophan, or prolactin response to 30 mg of d-fenfluramine. This study does not reveal evidence of abnormal brain 5-HT neuroendocrine function in hypercholesterolaemic patients receiving cholesterol-lowering medications and diet.

Effects of pravastatin on lipid levels, in vitro oxidizability of non-HDL lipoproteins and microalbuminuria in IDDM patients

The effects of pravastatin on plasma lipid levels, in vitro oxidizability of the non-HDL fraction, metabolic control, urinary albumin excretion, and four serum enzymes (SGPT, SGOT, GT and CPK) were studied in 20 insulin-dependent diabetic patients (IDDM) with incipient nephropathy. The patients were divided into two groups and the study was carried out by a crossover design. After 12 weeks pravastatin treatment (20 mg daily), plasma cholesterol, LDL-cholesterol and apolipoprotein B (Apo B) decreased by 22, 19 and 15%, respectively. The thiobarbituric acid reactive substances (TBARS) formation and the oxidation lagtime of the non-HDL fraction during the in vitro incubation with copper were not changed before and after treatment. The HbA1c and blood glucose levels, urinary albumin excretion, SGOT, SGPT and GT were not influenced by pravastatin treatment. CPK activity was elevated after 12 weeks of pravastatin treatment, and this elevation persisted even after the 12 weeks placebo period. So, pravastatin could be used as an effective drug for IDDM patients with incipient nephropathy, but close monitoring of the CPK activity is recommended.

Simvastatin. A reappraisal of its pharmacology and therapeutic efficacy in hypercholesterolaemia

Simvastatin is an HMG-CoA reductase inhibitor used in the treatment of patients with hypercholesterolaemia. Since the time simvastatin was previously reviewed in Drugs, a number of large clinical trials have confirmed its clinical efficacy. Thus, reductions from baseline were approximately 20 to 40% for serum levels of total cholesterol, 35 to 45% for low density lipoprotein (LDL)-cholesterol and 10 to 20% for triglycerides in patients with primary hypercholesterolaemia receiving simvastatin 10 to 40 mg/day. High density lipoprotein (HDL)-cholesterol levels were increased modestly by about 5 to 15%. Recent data from long term studies indicate that little or no attenuation of these changes in serum lipid and lipoprotein levels occurred with administration of simvastatin for 3 to 5.4 years. Comparative studies with other HMG-CoA reductase inhibitors (lovastatin, pravastatin and fluvastatin), which were lacking at the time of the previous review of simvastatin, demonstrated greater reductions in serum levels of total cholesterol and LDL-cholesterol with simvastatin than equal dosages of lovastatin or pravastatin. Reductions in serum levels of total cholesterol and LDL-cholesterol were similar between agents only when lovastatin or pravastatin were administered at a total daily dosage twice that of simvastatin and when fluvastatin was administered at a total daily dosage approximately 8 times that of simvastatin. In general, simvastatin 10 to 40 mg/day was also more effective than standard dosages of bile acid sequestrants, fibrates or probucol in lowering serum levels of total cholesterol and LDL-cholesterol; however, fibrates usually produced greater reductions in serum triglycerides and greater elevations in HDL-cholesterol levels. The Scandinavian Simvastatin Survival Study (4S), a large secondary prevention study in patients with coronary heart disease and concomitant hypercholesterolaemia, demonstrated that simvastatin 20 to 40 mg/day for a median of 5.4 years significantly reduced overall mortality (the primary end-point of the study) by 30% compared with placebo, which was attributed to a 42% relative reduction in coronary mortality. Coronary morbidity was also significantly reduced by simvastatin in the 4S trial. The tolerability profile of simvastatin appears to be comparable to that of other HMG-CoA reductase inhibitors. The most frequently reported adverse events are gastrointestinal disturbances, which are generally mild and tend to occur less frequently than with cholestyramine. In conclusion, simvastatin is among the most effective agents available for treating patients with hypercholesterolaemia.(ABSTRACT TRUNCATED AT 400 WORDS)

Antihyperglycaemic agents. Drug interactions of clinical importance

Non-insulin-dependent (type 2) diabetes mellitus (NIDDM) affects middle-aged or elderly people who frequently have several other concomitant diseases, especially obesity, hypertension, dyslipidaemias, coronary insufficiency, heart failure and arthropathies. Thus, polymedication is the rule in this population, and the risk of drug interactions is important, particularly in elderly patients. The present review is restricted to the interactions of other drugs with antihyperglycaemic compounds, and will not consider the mirror image, i.e. the interactions of antihyperglycaemic agents with other drugs. Oral antihyperglycaemic agents include sulphonylureas, biguanides--essentially metformin since the withdrawn of phenformin and buformin--and alpha-glucosidase inhibitors, acarbose being the only representative on the market. These drugs can be used alone or in combination to obtain better metabolic control, sometimes with insulin. Drug interactions with antihyperglycaemic agents can be divided into pharmacokinetic and pharmacodynamic interactions. Most pharmacokinetic studies concern sulphonylureas, whose action may be enhanced by numerous other drugs, thus increasing the risk of hypoglycaemia. Such an effect may result essentially from protein binding displacement, inhibition of hepatic metabolism and reduction of renal clearance. Reduction of the hypoglycaemic activity of sulphonylureas due to pharmacokinetic interactions with other drugs appears to be much less frequent. Drug interactions leading to an increase in plasma metformin concentrations, mainly by reducing the renal excretion or the hepatic metabolism of the biguanide, should be avoided to limit the risk of hyperlactaemia. Owing to its mode of action, pharmacokinetic interferences with acarbose are limited to the gastrointestinal tract, but have not been extensively studied yet. Pharmacodynamic interactions are quite numerous and may result in a potentiation of the hypoglycaemic action or, conversely, in a deterioration of blood glucose control. Such interactions may be observed whatever the type of antidiabetic treatment. They result from the intrinsic properties of the coprescribed drug on insulin secretion and action, or on a key step of carbohydrate metabolism. Finally, a combination of 2 to 3 antihyperglycaemic agents is common for treating patients with NIDDM to benefit from the synergistic effect of compounds acting on different sites of carbohydrate metabolism. Possible pharmacokinetic interactions between alpha-glucosidase inhibitors and classical antidiabetic oral agents should be better studied in the diabetic population.

Improvement of glucose tolerance by bezafibrate in non-obese patients with hyperlipidemia and impaired glucose tolerance

Glucose intolerance or diabetes mellitus, hyperlipidemia, obesity and hypertension may have a close interrelation based on insulin resistance. We selected 28 impaired glucose tolerance (IGT) patients with hyperlipidemia. The IGT patients demonstrated hypertriglyceridemia associated with hyperinsulinemia, a typical manifestation of insulin resistance. Administration of bezafibrate at 400 mg/day for 4 weeks to the IGT patients with hypertriglyceridemia resulted in an improvement of the plasma glucose level and insulin response to 75 g oral glucose loading associated with a concomitant decrease in non-esterified fatty acids. The ratio of the level of serum C-peptide to that of insulin after a 75 g oral glucose tolerance test (OGTT) was augmented after 4 weeks of bezafibrate administration. However, reduction of the cholesterol level with pravastatin did not alter these parameters. These results suggest that treatment to reduce the level of serum triglycerides, but not that of cholesterol, may have a beneficial effect for improving insulin resistance even in the non-obese subjects with IGT and decreasing the risk of coronary heart disease.

Efficacy and safety of fluvastatin in patients with non-insulin-dependent diabetes mellitus and hyperlipidemia

The purpose of this study was to investigate the triglyceride-lowering effect of fluvastatin, a new 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, in the combined hyperlipidemia of non-insulin-dependent diabetes mellitus (NIDDM). In this double-blind trial, 66 patients with NIDDM (24 men and 42 women, age 37-71), with low-density lipoprotein cholesterol (LDL-C) levels of 130-300 mg/dL (3.4-7.8 mmol/L) and triglyceride (TG) levels of 200-1,000 mg/dL (2.3-11.3 mmol/L) despite an 8-week period of diet modification, were randomized to receive either fluvastatin at 20 mg once daily (at night) or placebo for 6 weeks, followed by an increase of fluvastatin to 20 mg twice daily for an additional 6 weeks of treatment. After 12 weeks, fluvastatin decreased plasma levels of total cholesterol by 19.9% (p < 0.001), LDL-C by 24.3% (p < 0.001), TG by 15.3% (p < 0.01), very low-density lipoprotein cholesterol (VLDL-C) by 19.7% (p < 0.001), apolipoprotein (apo) B by 21.3% (p < 0.001), and apo E by 18.1% (p < 0.05), whereas high-density lipoprotein cholesterol (HDL-C) levels were increased by 4.6% (p < 0.05). Within the intermediate-density lipoprotein cholesterol (IDL-C) fraction, a constituent analysis revealed a total cholesterol reduction of 35% (p < 0.01). Greater decreases in TG were seen in patients who had higher levels of TG at baseline. Slight increases in glycemic indices and body weight were seen in both treatment groups. The occurrence of clinical and laboratory abnormalities was similar with both active treatment and placebo, and no myositis was observed. Slight increases in aspartate (ASAT; mean 5.6 U/L at the higher dose) and alanine (ALAT; mean 5.1 U/L at the higher dose) aminotransferases were not clinically significant. In this first, parallel-group placebo-controlled trial of a reductase inhibitor in a free-living NIDDM population, fluvastatin safely improved the combined TG, VLDL-C, IDL-C, LDL-C, and HDL-C abnormalities associated with NIDDM.

Simvastatin in non-insulin-dependent diabetes mellitus: effect on serum lipids, lipoproteins and haemostatic measures

The clinical efficacy of the 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMGCoA) reductase inhibitor simvastatin in the treatment of hypercholesterolaemia in non-insulin-dependent diabetes (NIDDM), was examined in a double-blind placebo-controlled study of 6 months in 70 patients with NIDDM (age 25-70 years), of whom 57 were randomised to placebo (29 patients) or simvastatin for 6 months, following a 3-month run-in on diet. Patients were hypercholesterolaemic (7.8 (7.6-8.0) (mean (95% confidence intervals)) mmol/l simvastatin vs. 8.0 (7.7-8.5) mmol/l placebo) and mildly hypertriglyceridaemic (2.6 (2.2-3.0) simvastatin vs. 2.9 (2.3-3.5) placebo). Other lipid measures and estimates of glycaemic control and haemostasis were similar in both groups. There were no significant changes in lipids, haemostatic factors, or measures of glycaemic control in the placebo treatment group. Conversely by the end of 24 weeks, simvastatin produced a 28% reduction in cholesterol (to 5.6 (5.0-6.2) mmol/l (P < 0.001)), a 38% reduction in LDL cholesterol (from 5.5 (5.4-5.6) mmol/l to 3.4 (2.8-4.0) mmol/l, P < 0.001), a 15% reduction in triglyceride (to 2.2 (1.8-2.6) mmol/l, P < 0.05, and a 9% rise in HDL (from 1.16 (1.07-1.25) to 1.23 (1.14-1.32) mmol/l, P < 0.05). Improvements in apolipoprotein B (apo B) (-28%, P < 0.001), the LDL cholesterol to apo B ratio (-20%, P < 0.001), and apo A1 (+15%, P < 0.001) were recorded. There were no effects upon fibrinogen, factor VII activity, factor VIII activity, or measures of glycaemic control (fasting glucose, insulin, C-peptide, or HbA1).(ABSTRACT TRUNCATED AT 250 WORDS)

Renal function and insulin sensitivity during simvastatin treatment in type 2 (non-insulin-dependent) diabetic patients with microalbuminuria

The effect of simvastatin (10-20 mg/day) on kidney function, urinary albumin excretion rate and insulin sensitivity was evaluated in 18 Type 2 (non-insulin-dependent) diabetic patients with microalbuminuria and moderate hypercholesterolaemia (total cholesterol > or = 5.5 mmol.l-1). In a double-blind, randomized and placebo-controlled design treatment with simvastatin (n = 8) for 36 weeks significantly reduced total cholesterol (6.7 +/- 0.3 vs 5.1 mmol.l-1 (p < 0.01)), LDL-cholesterol (4.4 +/- 0.3 vs 2.9 +/- 0.2 mmol.l-1 (p < 0.01)) and apolipoprotein B (1.05 +/- 0.04 vs 0.77 +/- 0.02 mmol.l-1 (p < 0.01)) levels as compared to placebo (n = 10). Both glomerular filtration rate (mean +/- SEM) (simvastatin: 96.6 +/- 8.0 vs 96.0 +/- 5.7 ml.min-1 x 1.73 m-2, placebo: 97.1 +/- 6.7 vs 88.8 +/- 6.0 ml.min-1 x 1.73 m-2)(NS) and urinary albumin excretion rate (geometric mean x/divided by antilog SEM) (simvastatin: 18.4 x/divided by 1.3 vs 16.2 x/divided by 1.2 microgram.min-1, placebo 33.1 x/divided by 1.3 vs 42.7 x/divided by 1.3 micrograms.min-1)(NS) were unchanged during the study. A euglycaemic hyperinsulinaemic clamp was performed at baseline and after 18 weeks in seven simvastatin- and nine placebo-treated patients. Isotopically determined basal and insulin-stimulated glucose disposal was similarly reduced before and during therapy in both the simvastatin (2.0 +/- 0.1 vs 1.9 +/- 0.1 (NS) and 3.1 +/- 0.6 vs 3.1 +/- 0.7 mg.kg-1 x min-1 (NS)) and the placebo group (1.9 +/- 0.1 vs 1.8 +/- 0.1 (NS) and 4.1 +/- 0.6 vs 3.8 +/- 0.2 mg.kg-1 x min-1 (NS)).(ABSTRACT TRUNCATED AT 250 WORDS)

HMG-CoA reductase inhibitor use in the aged. A review of clinical experience

While the benefit of cholesterol-lowering in the elderly has yet to be proven in clinical trials, individuals at high risk of coronary events who otherwise enjoy a good quality of life, should not be denied cholesterol-lowering therapy on the basis of age alone. Moreover, hypolipidaemic drugs are already extensively used in the aged. The HMG-CoA reductase inhibitors lovastatin, simvastatin and pravastatin are potent well tolerated hypolipidaemic therapies in young subjects. Although there have been few studies on their use in elderly subjects, the available data suggest the efficacy and safety of HMG-CoA reductase inhibitors in similar to that established for younger age groups.

Impaired left ventricular relaxation and hyperinsulinemia in patients with primary hypercholesterolemia

Fifteen non-obese patients with familial hypercholesterolemia and fifteen normocholesterolemic subjects matched for age, body mass index, waist/hip ratio, arterial blood pressure and sedentary life style underwent blood sampling for determination of fasting plasma glucose, insulin, total-, LDL-, HDL-cholesterol, triglycerides, free fatty acids, apolipoprotein A1 and B. In both groups of subjects we determined erythrocyte membrane microviscosity and performed an echocardiographic study. We demonstrated that hypercholesterolemic patients had a significant increase in fasting plasma total cholesterol (8.9 +/- 0.5 vs. 5.5 +/- 0.3 mmol/l, P less than 0.001), insulin (79 +/- 4 vs. 58 +/- 4 pmol/l, P less than 0.05) and apolipoprotein B (2.2 +/- 0.5 vs. 1.3 +/- 0.5 g/l P less than 0.01). In the echocardiographic study we found a significant impairment in left ventricular relaxation (isovolumic relaxation time (IRT) 106 +/- 6 vs. 73 +/- 7 ms, P less than 0.01). Erythrocyte membrane microviscosity (0.253 +/- 0.004 vs. 0.225 +/- 0.003, P less than 0.05) was also increased in hypercholesterolemic patients. Finally we found that erythrocyte membrane microviscosity correlated with fasting plasma insulin levels (r = -0.46, P less than 0.03) and IRT (r = -0.52, P less than 0.01).

Management of non-insulin-dependent diabetes mellitus

The initial management of non-insulin-dependent diabetes mellitus (NIDDM) should include patient education, dietary counselling and, when feasible, individualised physical activity. It is only when such measures fail that drug therapy should be considered. Dietary management of NIDDM includes a restriction in calories, and these should be appropriately distributed as carbohydrates, lipids and proteins. Supplementation of the diet with soluble fibre and supplementation with magnesium salts if hypomagnesaemia is demonstrated, is recommended. However, supplementation with fish oils or with fish oil-derived omega-3 fatty acids is not currently recommended. Oral drug therapies used in NIDDM include sulphonylurea derivatives, which are a first-line treatment in patients who are not grossly obese, metformin, which is the treatment of choice for obese patients, and alpha-glucosidase inhibitors such as acarbose, which are used mainly to reduce postprandial blood glucose peaks. These types of drugs can be used alone or in combination. Insulin therapy may be required to achieve adequate control of blood glucose levels in some patients. In several instances, it is suggested that insulin therapy be combined with sulphonylureas (essentially when residual insulin secretion is present), with metformin, or with alpha-glucosidase inhibitors. The treatment of disorders associated with NIDDM, such as obesity, hypertension or hyperlipidaemia, requires particular attention in diabetic patients, since some drugs can adversely affect glycaemic control. Oral drugs for the treatment of NIDDM include sulphonylurea derivatives used in first-line treatment in patients who are not grossly obese, metformin, which is often the treatment of choice for obese patients and, more recently, the alpha-glucosidase inhibitors, such as acarbose, which are effective in reducing the postprandial rise in blood glucose.