Preferable effect of pravastatin compared to atorvastatin on beta cell function in Japanese early-state type 2 diabetes with hypercholesterolemia

The current status of low-density lipoprotein cholesterol for primary prevention of coronary artery disease in late-stage elderly persons with type 2 diabetes mellitus: A retrospective, single-center study

Aims/Introduction

The importance of low‐density lipoprotein cholesterol (LDL‐C) in the primary prevention of cardiovascular disease has recently been reported in the population aged ≥75 years with hypercholesterolemia. Therefore, the current status of LDL‐C management for primary prevention of coronary artery disease in patients aged ≥75 years with type 2 diabetes mellitus was investigated.

Materials and Methods

A total of 124 patients aged ≥75 years who had type 2 diabetes mellitus, but no coronary artery disease, were investigated. The patients' background characteristics, LDL‐C, glycemic status, ankle‐brachial index and cardio‐ankle vascular index were compared between patients taking and not taking LDL‐C‐lowering agents, such as hydroxymethylglutaryl‐CoA reductase inhibitors (statins) and ezetimibe. The details of the antihyperlipidemic and antidiabetic agents used in the present study were also examined.

Results

LDL‐C was significantly lower in patients taking LDL‐C‐lowering agents (LDLCLT[+]) than in patients not taking them (LDLCLT[−]), although LDL‐C was maintained <120 mg/dL in both groups (93.0 mg/dL vs 102.1 mg/dL). Approximately half of the cases in the LDLCLT(+) group received moderate‐intensity statins, with pitavastatin being the most prescribed statin. Glycated hemoglobin was significantly lower in the LDLCLT(+) group than in the LDLCLT(−) group (6.9% vs 7.3%). Sodium‐glucose transporter 2 inhibitors were more frequently used in the LDLCLT(+) group than in the LDLCLT(−) group. The ankle‐brachial index/cardio‐ankle vascular index did not differ between the groups.

Conclusion

Low‐density lipoprotein cholesterol was properly managed for primary prevention of coronary artery disease in patients aged ≥75 years with type 2 diabetes mellitus regardless of the presence or absence of LDL‐C‐lowering agents.

Statin Treatment-Induced Development of Type 2 Diabetes: From Clinical Evidence to Mechanistic Insights

Statins are the gold-standard treatment for the prevention of primary and secondary cardiovascular disease, which is the leading cause of mortality worldwide. Despite the safety and relative tolerability of statins, observational studies, clinical trials and meta-analyses indicate an increased risk of developing new-onset type 2 diabetes mellitus (T2DM) after long-term statin treatment. It has been shown that statins can impair insulin sensitivity and secretion by pancreatic β-cells and increase insulin resistance in peripheral tissues. The mechanisms involved in these processes include, among others, impaired Ca²⁺ signaling in pancreatic β-cells, down-regulation of GLUT-4 in adipocytes and compromised insulin signaling. In addition, it has also been described that statins’ impact on epigenetics may also contribute to statin-induced T2DM via differential expression of microRNAs. This review focuses on the evidence and mechanisms by which statin therapy is associated with the development of T2DM. This review describes the multifactorial combination of effects that most likely contributes to the diabetogenic effects of statins. Clinically, these findings should encourage clinicians to consider diabetes monitoring in patients receiving statin therapy in order to ensure early diagnosis and appropriate management.

The statins effects on HbA1c control among diabetic patients: An umbrella review of systematic reviews and meta-analyses of observational studies and clinical trials

Statins have impacts on the metabolism of glucose that might influence the progress of diabetes in non-diabetics or affect glycemic control in patients with existing diabetes. Experimental proof has been contradictory about whether some statins display beneficial properties while others indicate harmful impressions. Some systematic reviews of statins had stated conflicting findings on the concern of glucose metabolism. The current study investigates the published systematic reviews and meta-analyses to combine their results and give a clear situation regarding the influence of statins therapy on glycated hemoglobin (HbA1c). This study has valuable strength points; long follow-up period and big sample size.

[Effect of Statins on Glycemic Status and Plasma Adiponectin Concentrations in Patients with Type 2 Diabetes Mellitus and Hypercholesterolemia]

It is reported that statins have inconsistent effects on glycemic status and adiponectin concentrations in patients with type 2 diabetes mellitus (T2DM). We aimed to investigate the effect of statins on these variables in patients with T2DM and hypercholesterolemia. A control group comprising 24 patients with T2DM but without hypercholesterolemia was observed for more than 12 weeks, while 24 patients with T2DM and hypercholesterolemia were treated with statins for the same period (statin group). The percentage changes in the glycemic status [blood glucose and glycated hemoglobin (HbA1c)], and levels of plasma adiponectin [total and high molecular weight (HMW)] were compared between the two groups. The statin group had reduced percentage changes in HbA1c, blood glucose, and total and HMW-adiponectin concentration percentage changes that were similar to those in the control group. However, when matched for sex, age (±5 years) and HbA1c (±0.5%) with the control group, the pravastatin group had reduced percentage changes in the plasma HMW-adiponectin concentrations than the matched controls (p=0.023). However, there were no differences in the percentage changes in the plasma total adiponectin (p=0.137), HbA1c (p=0.202), or blood glucose concentrations (p=0.450) between the two groups. Pravastatin treatment had no effect on the glycemic status of patients with T2DM and hypercholesterolemia, but may reduce the percentage changes in the plasma HMW-adiponectin concentrations. Hence, patients with T2DM and hypercholesterolemia receiving long-term treatment with pravastatin might experience increased insulin resistance.

Latest Updates on Lipid Management

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of death worldwide. Despite the clinical long-term and near-term benefits of lowering cholesterol in, respectively, primary and secondary prevention of ASCVD, cholesterol levels remain under-treated, with many patients not achieving their recommended targets. The present article will review the latest updates on lipid management with emphases on the different classes of cholesterol-lowering agents and their clinical uses.

Atorvastatin, but not pravastatin, inhibits cardiac Akt/mTOR signaling and disturbs mitochondrial ultrastructure in cardiac myocytes

Statins, which reduce LDL-cholesterol by inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, are among the most widely prescribed drugs. Skeletal myopathy is a known statin-induced adverse effect associated with mitochondrial changes. We hypothesized that similar effects would occur in cardiac myocytes in a lipophilicity-dependent manner between 2 common statins: atorvastatin (lipophilic) and pravastatin (hydrophilic). Neonatal cardiac ventricular myocytes were treated with atorvastatin and pravastatin for 48 h. Both statins induced endoplasmic reticular (ER) stress, but only atorvastatin inhibited ERK1/2^T202/Y204, Akt^Ser473, and mammalian target of rapamycin signaling; reduced protein abundance of caveolin-1, dystrophin, epidermal growth factor receptor, and insulin receptor-β; decreased Ras homolog gene family member A activation; and induced apoptosis. In cardiomyocyte-equivalent HL-1 cells, atorvastatin, but not pravastatin, reduced mitochondrial oxygen consumption. When male mice underwent atorvastatin and pravastatin administration per os for up to 7 mo, only long-term atorvastatin, but not pravastatin, induced elevated serum creatine kinase; swollen, misaligned, size-variable, and disconnected cardiac mitochondria; alteration of ER structure; repression of mitochondria- and endoplasmic reticulum-related genes; and a 21% increase in mortality in cardiac-specific vinculin-knockout mice during the first 2 months of administration. To our knowledge, we are the first to demonstrate in vivo that long-term atorvastatin administration alters cardiac ultrastructure, a finding with important clinical implications.-Godoy, J. C., Niesman, I. R., Busija, A. R., Kassan, A., Schilling, J. M., Schwarz, A., Alvarez, E. A., Dalton, N. D., Drummond, J. C., Roth, D. M., Kararigas, G., Patel, H. H., Zemljic-Harpf, A. E. Atorvastatin, but not pravastatin, inhibits cardiac Akt/mTOR signaling and disturbs mitochondrial ultrastructure in cardiac myocytes.

Assessing statin effects on cardiovascular pathways in HIV using a novel proteomics approach: Analysis of data from INTREPID, a randomized controlled trial

Background

People with HIV (PWH) demonstrate increased cardiovascular disease (CVD), due in part to increased immune activation, inflammation, and endothelial dysfunction.

Methods

In a randomized trial (INTREPID), 252 HIV-infected participants with dyslipidemia and no history of coronary artery disease were randomized (1:1) to pitavastatin 4 mg vs. pravastatin 40 mg for 52 weeks. Using a proteomic discovery approach, 92 proteins biomarkers were assessed using Proximity Extension Assay technology to determine the effects of statins on key atherosclerosis and CVD pathways among PWH. 225 participants had specimens available for biomarker analysis pre- and post-baseline.

Findings

The mean age was 49.5 ± 8.0 (mean ± SD), LDL-C 155 ± 25 mg/dl and CD4 count 620 ± 243 cell/mm³. Among all participants, three proteins significantly decreased: tissue factor pathway inhibitor [TFPI; t-statistic = −6.38, FDR p-value<0.0001], paraoxonase 3 [PON3; t-statistic = −4.64, FDR p-value = 0.0003], and LDL-receptor [LDLR; t-statistic = −4.45, FDR p-value = 0.0004]; and two proteins significantly increased galectin-4 [Gal-4; t-statistic = 3.50, FDR p-value = 0.01] and insulin-like growth factor binding protein 2 [IGFBP-2; t-statistic = 3.21, FDR p-value = 0.03]. The change in TFPI was significantly different between the pitavastatin and pravastatin groups. Among all participants, change in TFPI related to the change in LDL-C (r = 0.43, P < 0.0001) and change in Lp-PLA2 (r = 0.29, P < 0.0001).

Interpretation

Using a proteomics approach, we demonstrated that statins led to a significant reduction in the levels of TFPI, PON3, and LDLR and an increase in Gal-4 and IGFBP-2, key proteins involved in coagulation, redox signaling, oxidative stress, and glucose metabolism. Pitavastatin led to a greater reduction in TFPI than pravastatin. These data highlight potential novel mechanisms of statin effects among PWH.

Fund

This work was supported by an investigator-initiated grant to S.K.G. from KOWA Pharmaceuticals America, Inc. and the National Institutes of Health [P30 DK040561; Nutrition Obesity Research Center at Harvard]. M.T. was support by National Institutes of Health [5KL2TR001100-05; Harvard Catalyst KL2 grant].

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Among PWH, statins significantly decreased three proteins [tissue factor pathway inhibitor (TFPI), paraoxonase 3 (PON3), and LDL-receptor (LDLR)].

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Among PWH, statins significantly increased galectin-4 (Gal-4) and insulin-like growth factor binding protein 2 (IGFBP-2).

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The proteins significantly affected by statin therapy are involved in important pathways in atherosclerosis and cardiovascular disease.

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The change in TFPI was directly related to the change in LDL-C and a systemic marker of arterial inflammation (Lp-PLA2).

Risk and Benefits of Statins in Glucose Control Management of Type II Diabetes

Worldwide statins are considered to be the first-line pharmacological treatment for dyslipidemia and reducing the risk of coronary heart disease. However, recently various studies have shown its adverse effect on glucose control among diabetic patients and the U.S. Food and Drug Administration have revised statin drug labels to include information that increases in fasting serum glucose and glycated hemoglobin levels have been reported. This systematic review objective is to evaluate the risks and benefits of statins in glucose control management of type 2 diabetes patients based on the 44 published journal articles included and obtained through MEDLINE full text, PubMed, Science Direct, Pro Quest, SAGE, Taylor and Francis Online, Google Scholar, High Wire, and Elsevier Clinical Key. Statins were found to affect glucose control through several ways, namely, by affecting insulin production and secretion by β-pancreatic cells, insulin resistance, insulin uptake by the muscles and adipocytes and production of adipokines. Current evidence available shows that most of the statins give unfavorable side effects with regards to glucose control among diabetic patients. A dose-dependent and time-dependent effect was also observed in some statins which may be present among other statins as well.

Atorvastatin but Not Pravastatin Impairs Mitochondrial Function in Human Pancreatic Islets and Rat β-Cells. Direct Effect of Oxidative Stress

Statins are a class of drugs widely prescribed as frontline therapy for lowering plasma LDL-cholesterol in cardiovascular risk prevention. Several clinical reports have recently suggested an increased risk of type 2 diabetes associated with chronic use of these drugs. The pathophysiology of this effect remains to be fully elucidated but impaired β-cell function constitutes a potential mechanism. The aim of this study was to explore the effect of a chronic treatment with lipophilic and hydrophilic statins on β-cell function, using human pancreatic islets and rat insulin-secreting INS-1 cells; we particularly focused on the role of mitochondria and oxidative stress. The present study demonstrates, for the first time, that atorvastatin (lipophilic) but not pravastatin (hydrophilic) affected insulin release and mitochondrial metabolism due to the suppression of antioxidant defense system and induction of ROS production in pancreatic β-cell models. Mevalonate addition and treatment with a specific antioxidant (N-AcetylCysteine) effectively reversed the observed defects. These data demonstrate that mitochondrial oxidative stress is a key element in the pathogenesis of statin-related diabetes and may have clinical relevance to design strategies for prevention or reduction of statin induced β-cell dysfunction and diabetes in patients treated with lipophilic statins.

Treatment with atorvastatin attenuates progression of insulin resistance and pancreatic fibrosis in the Otsuka Long-Evans Tokushima fatty rats

PURPOSE

The effects of statins on insulin resistance (IR) and type 2 diabetes mellitus (T2DM) are still controversial and its effects on pancreatic fibrosis are poorly defined. The purpose of this study is to examine the effects of atorvastatin on these issues using the Otsuka Long-Evans Tokushima Fatty (OLETF) rat, an animal model of IR, T2DM and pancreatic fibrosis.

METHODS

Male OLETF rats were divided into 2 groups at 6weeks of age. The first group received a standard diet until the end of experimental period at age 28weeks. The second group was given a diet containing 0.05% atorvastatin from 6weeks of age, before the onset of IR and pancreatic fibrosis. The age-matched Long-Evans Tokushima Otsuka rats without presence of IR, T2DM and pancreatic fibrosis, received a standard diet and were used as a normal control.

RESULTS

Atorvastatin slightly decreased serum fasting glucose and insulin levels, but significantly improved index of IR compared with the untreated OLETF rats. In addition, atorvastatin markedly decreased transforming growth factor-β1 mRNA expression, myeloperoxidase activity and proportion of fibrotic area, and elevated superoxide dismutase activity in the pancreas compared with the untreated OLETF rats.

CONCLUSIONS

These findings suggest that atorvastatin exerts favorable influence on progression of IR and pancreatic inflammation and fibrosis via pleiotropic effect such as anti-oxidative property.

The diabetogenic action of statins - mechanisms and clinical implications

Treatment with statins has transformed primary and secondary prevention of cardiovascular disease (CVD), including thrombotic stroke. Evidence-based data demonstrate the benefits and safety of statin therapy and help to guide clinicians in the management of populations at high risk of CVD. Nevertheless, clinical trials, meta-analyses and observational studies highlight a 10-12% increase in new-onset diabetes mellitus (NODM) among patients receiving statins. The risk further increases with intensive therapy and among individuals with known risk factors for NODM. Mechanisms underpinning this effect are not yet fully understood; however, Mendelian randomization studies suggest that they are related to lowered activity of HMG-CoA reductase, the target of statin therapy. In vitro research indicates that statins potentially impair β-cell function and decrease insulin sensitivity but how these findings relate to patients is unknown. In the clinic, statins should be prescribed on the basis of CVD risk and individual patient characteristics. In addition, diet and lifestyle interventions should be emphasized to help mitigate the risk of NODM. Individuals who develop NODM while taking statins do not exhibit increased microvascular disease, which is reassuring. In diabetes mellitus of long duration, the effect of statins on glycaemic control is small and unlikely to be clinically important.

Biochemistry of Statins

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality worldwide. Elevated blood lipids may be a major risk factor for CVD. Due to consistent and robust association of higher low-density lipoprotein (LDL)-cholesterol levels with CVD across experimental and epidemiologic studies, therapeutic strategies to decrease risk have focused on LDL-cholesterol reduction as the primary goal. Current medication options for lipid-lowering therapy include statins, bile acid sequestrants, a cholesterol-absorption inhibitor, fibrates, nicotinic acid, and omega-3 fatty acids, which all have various mechanisms of action and pharmacokinetic properties. The most widely prescribed lipid-lowering agents are the HMG-CoA reductase inhibitors, or statins. Since their introduction in the 1980s, statins have emerged as the one of the best-selling medication classes to date, with numerous trials demonstrating powerful efficacy in preventing cardiovascular outcomes (Kapur and Musunuru, 2008 [1]). The statins are commonly used in the treatment of hypercholesterolemia and mixed hyperlipidemia. This chapter focuses on the biochemistry of statins including their structures, pharmacokinetics, and mechanism of actions as well as the potential adverse reactions linked to their clinical uses.

The Different Effects of Atorvastatin and Pravastatin on Cell Death and PARP Activity in Pancreatic NIT-1 Cells

Statins have been widely used drugs for lowering low-density lipoprotein and for preventing heart attack and stroke. However, the increased risk for developing diabetes during extended stain use and the molecular mechanisms remain unclear. The objective of this study was to elucidate the signaling pathway and biological function between necrosis and autophagy induced by atorvastatin (AS) and pravastatin (PS). Here we observed that atorvastatin (AS) can increase intracellular reactive oxygen species (ROS) and induce necrotic cell death and autophagy in NIT-1 cells, whereas pravastatin (PS) does not cause ROS and cell death but also induces autophagy. PARP1 exhibited a dual role in modulating necrosis and autophagy in AS- and PS-treated NIT-1 cells through RIP1-RIP3-MLKL pathway and PARP1-AMPK-mTOR pathway. Lastly, AS treatment induced mitochondrial morphology injury significantly more than PS treatment did. Thus, the PARP1 activation should be considered in the development of effective statin therapies for diabetes. Future studies may examine specific mechanisms and pathways in mitochondria, autophagy, and oxidative stress in vivo.

Chronic HMGCR/HMG-CoA reductase inhibitor treatment contributes to dysglycemia by upregulating hepatic gluconeogenesis through autophagy induction

Statins (HMGCR/HMG-CoA reductase [3-hydroxy-3-methylglutaryl-CoA reductase] inhibitors) are widely used to lower blood cholesterol levels but have been shown to increase the risk of type 2 diabetes mellitus. However, the molecular mechanism underlying diabetogenic effects remains to be elucidated. Here we show that statins significantly increase the expression of key gluconeogenic enzymes (such as G6PC [glucose-6-phosphatase] and PCK1 (phosphoenolpyruvate carboxykinase 1 [soluble]) in vitro and in vivo and promote hepatic glucose output. Statin treatment activates autophagic flux in HepG2 cells. Acute suppression of autophagy with lysosome inhibitors in statin treated HepG2 cells reduced gluconeogenic enzymes expression and glucose output. Importantly, the ability of statins to increase gluconeogenesis was impaired when ATG7 was deficient and BECN1 was absent, suggesting that autophagy plays a critical role in the diabetogenic effects of statins. Moreover autophagic vacuoles and gluconeogenic genes expression in the liver of diet-induced obese mice were increased by statins, ultimately leading to elevated hepatic glucose production, hyperglycemia, and insulin resistance. Together, these data demonstrate that chronic statin therapy results in insulin resistance through the activation of hepatic gluconeogenesis, which is tightly coupled to hepatic autophagy. These data further contribute to a better understanding of the diabetogenic effects of stains in the context of insulin resistance.

Statin treatment, new-onset diabetes, and other adverse effects: a systematic review

Statin treatment prevents cardiovascular diseases probably beyond their lipid-lowering effect. Increasing evidence suggests that statins might increase the risk of new-onset diabetes; however, diabetes is known to increase the risk of cardiovascular diseases. The majority of the literature suggests an increased risk of new-onset diabetes in patients treated with statins in a number of different settings and that the risk appears greatest among the more potent statins. Furthermore, a dose-response curve has been shown between statin treatment and the development of diabetes. Possible mechanisms include muscle insulin resistance, lower expression of GLUT-4 in adipocytes impairing glucose tolerance and suppression of glucose-induced elevation of intracellular Ca(2+) level. However, other side effects have been reported such as increased risk of myotoxicity, increased liver enzymes, cataracts, mood disorders, dementias, hemorrhagic stroke and peripheral neuropathy, which should maybe be added to the increased risk of new-onset diabetes, when considering the risk- benefit ratio of statin treatment.

Statin treatment and new-onset diabetes: a review of proposed mechanisms

New-onset diabetes has been observed in clinical trials and meta-analyses involving statin therapy. To explain this association, three major mechanisms have been proposed and discussed in the literature. First, certain statins affect insulin secretion through direct, indirect or combined effects on calcium channels in pancreatic β-cells. Second, reduced translocation of glucose transporter 4 in response to treatment results in hyperglycemia and hyperinsulinemia. Third, statin therapy decreases other important downstream products, such as coenzyme Q10, farnesyl pyrophosphate, geranylgeranyl pyrophosphate, and dolichol; their depletion leads to reduced intracellular signaling. Other possible mechanisms implicated in the effect of statins on new-onset diabetes are: statin interference with intracellular insulin signal transduction pathways via inhibition of necessary phosphorylation events and reduction of small GTPase action; inhibition of adipocyte differentiation leading to decreased peroxisome proliferator activated receptor gamma and CCAAT/enhancer-binding protein which are important pathways for glucose homeostasis; decreased leptin causing inhibition of β-cells proliferation and insulin secretion; and diminished adiponectin levels. Given that the magnitude of the risk of new-onset diabetes following statin use remains to be fully clarified and the well-established beneficial effect of statins in reducing cardiovascular risk, statins remain the first-choice treatment for prevention of CVD. Elucidation of the mechanisms underlying the development of diabetes in association with statin use may help identify novel preventative or therapeutic approaches to this problem and/or help design a new generation statin without such side-effects.

Differential impact of statin on new-onset diabetes in different age groups: a population-based case-control study in women from an asian country

Background

Statins reduce cardiovascular risks but increase the risk of new-onset diabetes (NOD). The aim of this study is to determine what effect, if any, statins have on the risk of NOD events in a population-based case-control study. An evaluation of the relationship between age and statin-exposure on NOD risks was further examined in a female Asian population.

Method

In a nationwide case-controlled study, the authors assessed 1065 female NOD patients and 10650 controls with matching ages, genders and physician visit dates. The impact of statin-exposure on NOD was examined through multiple logistic regression models. Subgroup analysis for exploring the risk of NOD and statin-exposure in different age groups was performed.

Results

Statin-exposure was statistically significantly associated with increased new-onset diabetes risks using multivariate analysis. Interaction effect between age and statin-exposure on NOD risk was noted. For atorvastatin, the risk of cDDDs>60 was highest among the 55–64 year-olds (adjusted odds ratio [OR], 8.0; 95% confidence interval [CI], 2.57–24.90). For rosuvastatin, the risk of cDDDs>60 was highest among the 40–54 year-olds (adjusted OR, 14.8; 95% CI, 2.27–96.15). For simvastatin, the risk of cDDDs>60 was highest among the 55–64 year-olds (adjusted OR, 15.8; 95% CI, 5.77–43.26). For pravastatin, the risk of cDDDs>60 was highest among the 55–64 year-olds (adjusted OR, 14.0; 95% CI, 1.56–125.18).

Conclusions

This population-based study found that statin use is associated with an increased risk of NOD in women. The risk of statin-related NOD was more evident for women aged 40–64 years compared to women aged 65 or more, and was cumulative-dose dependent. The use of statins should always be determined by weighing the clinical benefits and potential risks for NOD, and the patients should be continuously monitored for adverse effects.

Comparison of effects of pitavastatin and atorvastatin on glucose metabolism in type 2 diabetic patients with hypercholesterolemia

AIMS/INTRODUCTION

The distinct effects of different statins on glycemic control have not been fully evaluated. In this open-label, prospective, cross-over clinical trial, we compared the effects of pitavastatin and atorvastatin on glycemic control in type 2 diabetic patients with hypercholesterolemia.

MATERIALS AND METHODS

A total of 28 Japanese type 2 diabetics with hypercholesterolemia treated with rosuvastatin (2.5 mg/day) for at least 8 weeks were recruited to this quasi-randomized cross-over study. At study entry, the patients assigned to sequence 1 received pitavastatin (2 mg/day) for 12 weeks in period 1 and atorvastatin (10 mg/day) for another 12 weeks in period 2, whereas patients assigned to sequence 2 received atorvastatin (10 mg/day) for 12 weeks in period 1 and pitavastatin (2 mg/day) for another 12 weeks in period 2. Blood samples were collected at three visits (baseline, after 12 and 24 weeks).

RESULTS

Lipid control was similar in both statins. The difference in glycated hemoglobin between pitavastatin and atorvastatin treatments was -0.18 (95% confidence interval -0.34 to -0.02; P = 0.03). Compared with atorvastatin, pitavastatin treatment significantly lowered the levels of glycoalbumin, fasting glucose and homeostasis model assessment of insulin resistance.

CONCLUSIONS

Our results showed that treatment with pitavastatin had a more favorable outcome on glycemic control in patients with type 2 diabetes compared with atorvastatin. This trial was registered with UMIN (no. 000003554).

Comparison of effects of cilnidipine and azelnidipine on blood pressure, heart rate and albuminuria in type 2 diabetics with hypertension: A pilot study

Previous studies reported that both cilnidipine and azelnidipine have a renoprotective effect compared with amlodipine. The aim of this study was to compare the effects of cilnidipine and azelnidipine on blood pressure, heart rate and albuminuria. An open-label prospective crossover trial was carried out. We recruited 19 type 2 diabetics treated with amlodipine (5 mg/day) at least for 12 weeks. At study entry, amlodipine was changed to cilnidipine (10 mg/day) or azelnidipine (16 mg/day) and each administered for 16 weeks. Then, the drugs were switched and the treatment was continued for another 16 weeks. Despite no differences in 24-h blood pressure and heart rate between cilnidipine and azelnidipine, treatment with cilnidipine resulted in a greater reduction in urinary albumin:creatinine ratio than azelnidipine. Our results suggested that cilnidipine is more efficient in reducing albuminuria than azelnidipine independent of its blood pressure lowering effect in type 2 diabetic patients with hypertension. This trial was registered with UMIN (no. 000007201).

Effects of pravastatin and atorvastatin on HDL cholesterol and glucose metabolism in patients with dyslipidemia and glucose intolerance: the PRAT study

AIMS

While statins have the property of increasing high-density lipoprotein cholesterol (HDL-C) in addition to lowering low-density lipoprotein cholesterol (LDL-C), a potential adverse effect on glucose metabolism has raised a concern over statin therapy. In a comparative trial, we investigated the effects of low-dose pravastatin and atorvastatin on HDL-C and glucose metabolism in patients with elevated LDL-C levels and glucose intolerance.

METHODS

Eligible patients were men aged ≥20 years or postmenopausal women who had LDL-C ≥140 mg/dL, HDL-C <80 mg/dL, and triglycerides <500 mg/dL and who had glucose intolerance. The patients were randomly allocated to either pravastatin (10 mg/day) or atorvastatin (10 mg/day) treatment for 12 months in an unblinded fashion. The percent changes from the baseline were compared between the treatments.

RESULTS

Of 202 patients who were randomized to either of the two treatments, 195 patients started the study medication, and 187 patients underwent the follow-up measurements at 6 or 12 months (pravastatin, n= 93; atorvastatin, n= 94). HDL-C increased by 4.3% (p= 0.03) in the pravastatin group and by 5.8% (p=0.0005) in the atorvastatin group and showed no between-group difference (p= 0.38). LDL-C decreased substantially in both groups (pravastatin, 21.5%; atorvastatin, 35.5%), and the decrease was much greater in the atorvastain group (p<0.0001). HbA1c slightly increased in both groups, but showed no measurable difference in the increase between the two treatments (p=0.30).

CONCLUSION

Pravastatin and atorvastatin of 10 mg per day each increased HDL-C by almost the same extent. These two statins did not show a differential effect on glucose metabolism.

Cardiovascular event reduction versus new-onset diabetes during atorvastatin therapy: effect of baseline risk factors for diabetes

OBJECTIVES

The purpose of this study was to compare the incidence of new-onset diabetes (NOD) with cardiovascular (CV) event reduction at different levels of NOD risk.

BACKGROUND

Statins reduce the number of CV events but increase the incidence of NOD. We previously reported that 4 factors independently predicted NOD: fasting blood glucose >100 mg/dl, fasting triglycerides >150 mg/dl, body mass index >30 kg/m(2), and history of hypertension.

METHODS

We compared NOD incidence with CV event reduction among 15,056 patients with coronary disease but without diabetes at baseline in the TNT (Treating to New Targets) (n = 7,595) and IDEAL (Incremental Decrease in Endpoints Through Aggressive Lipid Lowering) (n = 7,461) trials. CV events included coronary heart disease death, myocardial infarction, stroke, and resuscitated cardiac arrest.

RESULTS

Among 8,825 patients with 0 to 1 of the aforementioned NOD risk factors at baseline, NOD developed in 142 of 4,407 patients in the atorvastatin 80 mg group and in 148 of 4,418 in the atorvastatin 10 mg and simvastatin 20 to 40 mg groups (3.22% vs. 3.35%; hazard ratio [HR]: 0.97; 95% confidence intervals [CI]: 0.77 to 1.22). Among the remaining 6,231 patients with 2 to 4 NOD risk factors, NOD developed in 448 of 3,128 in the atorvastatin 80 mg group and in 368 of 3,103 in the lower-dose groups (14.3% vs. 11.9%; HR: 1.24; 95% CI: 1.08 to 1.42; p = 0.0027). The number of CV events was significantly reduced with atorvastatin 80 mg in both NOD risk groups.

CONCLUSIONS

Compared with lower-dose statin therapy, atorvastatin 80 mg/day did not increase the incidence of NOD in patients with 0 to 1 NOD risk factors but did, by 24%, among patients with 2 to 4 NOD risk factors. The number of CV events was significantly reduced with atorvastatin 80 mg in both NOD risk groups.

Predictors of new-onset diabetes in patients treated with atorvastatin: results from 3 large randomized clinical trials

OBJECTIVES

We sought to examine the incidence and clinical predictors of new-onset type 2 diabetes mellitus (T2DM) within 3 large randomized trials with atorvastatin.

BACKGROUND

Statin therapy might modestly increase the risk of new-onset T2DM.

METHODS

We used a standard definition of diabetes and excluded patients with prevalent diabetes at baseline. We identified baseline predictors of new-onset T2DM and compared the event rates in patients with and without new-onset T2DM.

RESULTS

In the TNT (Treating to New Targets) trial, 351 of 3,798 patients randomized to 80 mg of atorvastatin and 308 of 3,797 randomized to 10 mg developed new-onset T2DM (9.24% vs. 8.11%, adjusted hazard ratio [HR]: 1.10, 95% confidence interval [CI]: 0.94 to 1.29, p = 0.226). In the IDEAL (Incremental Decrease in End Points Through Aggressive Lipid Lowering) trial, 239 of 3,737 patients randomized to atorvastatin 80 mg/day and 208 of 3,724 patients randomized to simvastatin 20 mg/day developed new-onset T2DM (6.40% vs. 5.59%, adjusted HR: 1.19, 95% CI: 0.98 to 1.43, p = 0.072). In the SPARCL (Stroke Prevention by Aggressive Reduction in Cholesterol Levels) trial, new-onset T2DM developed in 166 of 1,905 patients randomized to atorvastatin 80 mg/day and in 115 of 1,898 patients in the placebo group (8.71% vs. 6.06%, adjusted HR: 1.37, 95% CI: 1.08 to 1.75, p = 0.011). In each of the 3 trials, baseline fasting blood glucose, body mass index, hypertension, and fasting triglycerides were independent predictors of new-onset T2DM. Across the 3 trials, major cardiovascular events occurred in 11.3% of patients with and 10.8% of patients without new-onset T2DM (adjusted HR: 1.02, 95% CI: 0.77 to 1.35, p = 0.69).

CONCLUSIONS

High-dose atorvastatin treatment compared with placebo in the SPARCL trial is associated with a slightly increased risk of new-onset T2DM. Baseline fasting glucose level and features of the metabolic syndrome are predictive of new-onset T2DM across the 3 trials.

Rosuvastatin, inflammation, C-reactive protein, JUPITER, and primary prevention of cardiovascular disease--a perspective

The major public health concern worldwide is coronary heart disease, with dyslipidemia as a major risk factor. Statin drugs are recommended by several guidelines for both primary and secondary prevention. Rosuvastatin has been widely accepted because of its efficacy, potency, and superior safety profile. Inflammation is involved in all phases of atherosclerosis, with the process beginning in early youth and advancing relentlessly for decades throughout life. C-reactive protein (CRP) is a well-studied, nonspecific marker of inflammation which may reflect general health risk. Considerable evidence suggests CRP is an independent predictor of future cardiovascular events, but direct involvement in atherosclerosis remains controversial. Rosuvastatin is a synthetic, hydrophilic statin with unique stereochemistry. A large proportion of patients achieve evidence-based lipid targets while using the drug, and it slows progression and induces regression of atherosclerotic coronary lesions. Rosuvastatin lowers CRP levels significantly. The Justification for Use of statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER) trial was designed after the observation that when both low density lipoprotein and CRP were reduced, patients fared better than when only LDL was lowered. Advocates and critics alike acknowledge that the benefits of rosuvastatin in JUPITER were real. After a review, the US Food and Drug Administration extended the indications for rosuvastatin to include asymptomatic JUPITER-eligible individuals with one additional risk factor. The American Heart Association and Centers of Disease Control and Prevention had previously recognized the use of CRP in persons with "intermediate risk" as defined by global risk scores. The Canadian Cardiovascular Society guidelines went further and recommended use of statins in persons with low LDL and high CRP levels at intermediate risk. The JUPITER study focused attention on ostensibly healthy individuals with "normal" lipid profiles and high CRP values who benefited from statin therapy. The backdrop to JUPITER during this period was an increasing awareness of a rising cardiovascular risk burden and imperfect methods of risk evaluation, so that a significant number of individuals were being denied beneficial therapies. Other concerns have been a high level of residual risk in those who are treated, poor patient adherence, a need to follow guidelines more closely, a dual global epidemic of obesity and diabetes, and a progressively deteriorating level of physical activity in the population. Calls for new and more effective means of reducing risk for coronary heart disease are intensifying. In view of compelling evidence supporting earlier and aggressive therapy in people with high risk burdens, JUPITER simply offers another choice for stratification and earlier risk reduction in primary prevention patients. When indicated, and in individuals unwilling or unable to change their diet and lifestyles sufficiently, the benefits of statins greatly exceed the risks. Two side effects of interest are myotoxicity and an increase in the incidence of diabetes.

Differential metabolic effects of distinct statins

Reciprocal relationships between endothelial dysfunction and insulin resistance suggest that therapies improving endothelial dysfunction will simultaneously improve insulin sensitivity and other metabolic parameters. However, previous studies with some statins either did not alter insulin sensitivity or promoted insulin resistance despite significant improvements in endothelial dysfunction and decreases in circulating pro-inflammatory markers. This may be due to pleiotropic or off-target effects of some statins to cause insulin resistance by diverse mechanisms unrelated to endothelial dysfunction. Indeed, there is evidence of other differential metabolic actions of distinct statins including effects on hydroxymethylglutaryl-CoA reductase inhibition, isoprotenoid synthesis, calcium release, glucose transport, insulin secretion, and/or insulin resistance. Pravastatin increases expression of adiponectin mRNA, enhances adiponectin secretion, increases plasma levels of adiponectin, and enhances insulin sensitivity in mice and humans. Clinical studies including large scale randomized controlled trials demonstrate potential differences between individual statins, with pravastatin promoting risk reduction for new onset of diabetes. Conversely, other statins including atorvastatin, rosuvastatin, and simvastatin all promote significant increase in this risk. Given the frequent concordance of metabolic diseases including diabetes, obesity, and metabolic syndrome with cardiovascular diseases associated with hyperlipidemia, it is important to understand the potential metabolic risks and benefits of therapies with distinct statins. In this review, we discuss these differential effects of statins on metabolic homeostasis and insulin sensitivity.

Pravastatin potentiates increases in serum adiponectin concentration in dyslipidemic patients receiving thiazolidinedione: the DOLPHIN study

AIM

A reduced risk of type 2 diabetes has been reported following treatment with pravastatin. Adiponectin is an adipocyte-derived protein that has an antidiabetic property. The objective of this study was to evaluate the effect of pravastatin on serum adiponectin concentration and other influencing factors.

METHODS

This study was a multicenter observational study: Dyslipidemia Open-labeled observational study by Lipid-lowering therapy with Pravastatin of the effect on High-molecular weight adiponectin in Nippon Yokohama (DOLPHIN). The protocol was registered in the UMIN Clinical Trial Registry as UMIN000000791. All patients received pravastatin 10 mg/day for 6 months and the change in concentration of total and high molecular weight adiponectin was assessed before and after follow-up. The difference in the change in total adiponectin concentration by patient characteristics was analyzed by an unpaired t-test. Influences of continuous variable factors on the change in total adiponectin concentration were estimated by simple linear regression analyses. Finally, in order to estimate the influences of factors that potentially affect the change in total adiponectin concentration induced by pravastatin, multiple linear regression analysis was conducted.

RESULTS

After 6 months, total adiponectin concentration was increased significantly by 23.2% from 11.7±6.4 to 13.7±8.6 µg/mL (p=0.002). The use of thiazolidinedione as a concomitant medication was the only significant influencing factor (β=0.580, p<0.001).

CONCLUSION

Pravastatin increased the serum adiponectin concentration in Japanese dyslipidemic patients without previous coronary artery disease. Interestingly, this effect was seen synergistically in combination with thiazolidinedione.

Differing effect of statins on insulin sensitivity in non-diabetics: a systematic review and meta-analysis

BACKGROUND

To determine whether individual statins had differing effects on insulin sensitivity (IS) in patients without pre-existing diabetes mellitus.

METHODS

A systematic literature search of MEDLINE, EMBASE and Cochrane CENTRAL was conducted through December 2008. Trials were included if they compared pravastatin, atorvastatin, rosuvastatin or simvastatin to placebo/control, excluded patients with diabetes, and reported data on insulin sensitivity/resistance. IS data was pooled and evaluated as standardized mean differences (SMDs) and 95% confidence interval (CI) using a random-effects model.

RESULTS

16 studies (n=1146) were included, with patients receiving pravastatin in three trials (n=164), atorvastatin in five trials (n=315), rosuvastatin in five trials (n=419), and simvastatin in five trials (n=369). When pooled as a class, statins had no significant impact on IS as compared with placebo/control [SMD -0.084 (95% CI -0.210 to 0.042); p=0.19]. Pravastatin was found to significantly improved IS [SMD 0.342 (95% CI 0.032-0.621); p=0.03], whereas simvastatin significantly worsened IS [SMD -0.321 (95% CI -0.526 to -0.117); p=0.03].

CONCLUSIONS

Statins do not appear to demonstrate a 'class effect' on IS in patients without diabetes. Differences between individual statins likely exist that may partially explain the findings of previously conducted meta-analyses examining the impact of statins on the development of diabetes.

Worsening of hyperglycemia due to atorvastatin in a renal transplant patient

New-onset diabetes mellitus post-renal transplantation [post-transplantation diabetes mellitus (PTDM)] and impaired glucose tolerance are among the most serious adverse metabolic disturbances of kidney transplants. We report a renal transplant patient whose mild post-transplant hyperglycaemia considerably worsened upon substituting atorvastatin for pravastatin. The patient was a 58-years-old Caucasian man who underwent living, non-related kidney transplantation. The mean blood sugar level (BSL) following transplantation was 113.8 mg/dl. In an attempt to reduce LDL cholesterol, atorvastatin 40 mg/day was substituted for pravastatin. Soon after commencement of atorvastatin, polydipsia and polyuria appeared. Both fasting and 2-h post-prandial BSL values increased, while there was no change in the patient's medications, dietary habits and renal function. Upon reverting back to pravastatin, BSL promptly declined to the previously mentioned baseline values. Since PTDM is a strong independent factor of graft failure, cardiovascular events and mortality, physicians should be made aware of this possible adverse effect of atorvastatin on glucose tolerance.

Effects of combined olmesartan and pravastatin on glucose intolerance and cardiovascular remodeling in a metabolic-syndrome model

Hypertension and dyslipidemia frequently coexist in patients with progressive insulin resistance and thus constitute metabolic syndrome. We sought to determine the merits of combining an angiotensin II receptor blocker and a 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor in treating this pathological condition. Five-week-old Otsuka Long-Evans Tokushima Fatty rats, a model of metabolic syndrome, were untreated or treated with olmesartan 3 mg kg(-1) per day, pravastatin 30 mg kg(-1) per day or their combination for 25 weeks. Long-Evans Tokushima Otsuka rats served as normal controls. The antihypertensive effect of olmesartan and the lipid-lowering properties of pravastatin were both augmented by the combination. The oral glucose tolerance test revealed that only the combined treatment significantly reduced the area under the time-glucose curve, which was accompanied by augmented adiponectin messenger RNA expression in epididymal adipose tissue. Although the total cardiac endothelial nitric oxide synthetase (eNOS) content did not significantly differ among the groups, the combined treatment significantly increased the content of dihydrofolate reductase, a key eNOS coupler. Dihydroethidium staining of the aorta showed that the combination most significantly attenuated superoxide production. Moreover, Azan-Mallory staining revealed that the combination most significantly limited the perivascular fibrosis and wall thickening of intramyocardial coronary arteries. In conclusion, the combination of olmesartan and pravastatin augmented adiponectin expression in white adipose tissue and improved glucose tolerance in a rat model of metabolic syndrome, which was associated with more significant ameliorations of cardiovascular redox state and remodeling than those by treatments with either agent alone.

Effects of atorvastatin and pravastatin on glucose tolerance, adipokine levels and inflammatory markers in hypercholesterolaemic patients

Several randomized clinical trials have suggested that atorvastatin and pravastatin may differ in terms of their pleiotropic effects. To verify this, we compared the effects of both statins on glucose tolerance, adipokine concentrations and inflammatory markers. A total of 36 hypercholesterolaemic patients without known coronary heart disease (CHD) were enrolled in an open-label, randomized, crossover study. The patients received pravastatin or atorvastatin (10 mg/day) for 4 months and then switched to the other statin for an additional 4 months. At the end of both treatment periods, atorvastatin significantly reduced the concentration of serum lipids (total and low-density lipoprotein-cholesterol and triglycerides) and inflammatory markers (high-sensitivity C-reactive protein and tumour necrosis factor-a) and increased serum adiponectin levels compared with pravastatin treatment. Although these effects would be expected to improve insulin sensitivity, atorvastatin did not affect glucose tolerance, which was assessed by fasting glucose and insulin concentrations, the homeostasis model assessment index and glycosylated haemoglobin (HbA(1c)) levels. Only obese patients showed increased HbA(1c) levels after atorvastatin treatment. Our results suggest that atorvastatin has both advantages and disadvantages compared with pravastatin treatment. Further studies are required to compare the relative clinical value of atorvastatin and pravastatin, especially in obese patients without CHD.