Differential metabolic effects of rosuvastatin and pravastatin in hypercholesterolemic patients

Pravastatin for lowering lipids

BACKGROUND

A detailed summary and meta-analysis of the dose-related effect of pravastatin on lipids is not available.

OBJECTIVES

Primary objective To assess the pharmacology of pravastatin by characterizing the dose-related effect and variability of the effect of pravastatin on the surrogate marker: low-density lipoprotein (LDL cholesterol). The effect of pravastatin on morbidity and mortality is not the objective of this systematic review. Secondary objectives • To assess the dose-related effect and variability of effect of pravastatin on the following surrogate markers: total cholesterol; high-density lipoprotein (HDL cholesterol); and triglycerides. • To assess the effect of pravastatin on withdrawals due to adverse effects.

SEARCH METHODS

The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials (RCTs) up to September 2021: CENTRAL (2021, Issue 8), Ovid MEDLINE, Ovid Embase, Bireme LILACS, the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions.

SELECTION CRITERIA

Randomized placebo-controlled trials evaluating the dose response of different fixed doses of pravastatin on blood lipids over a duration of three to 12 weeks in participants of any age with and without evidence of cardiovascular disease.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility criteria for studies to be included, and extracted data. We entered lipid data from placebo-controlled trials into Review Manager 5 as continuous data and withdrawal due to adverse effects (WDAEs) data as dichotomous data. We searched for WDAEs information from all trials. We assessed all trials using Cochrane's risk of bias tool under the categories of sequence generation, allocation concealment, blinding, incomplete outcome data, selective reporting, and other potential biases.

MAIN RESULTS

Sixty-four RCTs evaluated the dose-related efficacy of pravastatin in 9771 participants. The participants were of any age, with and without evidence of cardiovascular disease, and pravastatin effects were studied within a treatment period of three to 12 weeks. Log dose-response data over the doses of 5 mg to 160 mg revealed strong linear dose-related effects on blood total cholesterol and LDL cholesterol, and a weak linear dose-related effect on blood triglycerides. There was no dose-related effect of pravastatin on blood HDL cholesterol. Pravastatin 10 mg/day to 80 mg/day reduced LDL cholesterol by 21.7% to 31.9%, total cholesterol by 16.1% to 23.3%,and triglycerides by 5.8% to 20.0%. The certainty of evidence for these effects was judged to be moderate to high. For every two-fold dose increase there was a 3.4% (95% confidence interval (CI) 2.2 to 4.6) decrease in blood LDL cholesterol. This represented a dose-response slope that was less than the other studied statins: atorvastatin, rosuvastatin, fluvastatin, pitavastatin and cerivastatin. From other systematic reviews we conducted on statins for its effect to reduce LDL cholesterol, pravastatin is similar to fluvastatin, but has a decreased effect compared to atorvastatin, rosuvastatin, pitavastatin and cerivastatin. The effect of pravastatin compared to placebo on WADES has a risk ratio (RR) of 0.81 (95% CI 0.63 to 1.03). The certainty of evidence was judged to be very low.

AUTHORS' CONCLUSIONS

Pravastatin lowers blood total cholesterol, LDL cholesterol and triglyceride in a dose-dependent linear fashion. This review did not provide a good estimate of the incidence of harms associated with pravastatin because of the lack of reporting of adverse effects in 48.4% of the randomized placebo-controlled trials.

Effects of statin therapy on glycemic control and insulin resistance: A systematic review and meta-analysis

AIMS

To update the evidence about the diabetogenic effect of statins.

METHODS

We searched for randomized-controlled trials reporting the effects of statin therapy on glycosylated hemoglobin (HbA1c) and/or homeostatic model insulin resistance (i.e., HOMA-IR) as indexes of diabetes. Studies were classified between the ones testing normal vs individuals with already altered glycemic control (HbA1c ≥ 6.5%; and HOMA-IR ≥ 2.15). Furthermore, studies were separated by statin type and dosage prescribed. Data are presented as mean difference (MD) and 95% confidence intervals.

RESULTS

A total of 67 studies were included in the analysis (>25,000 individuals). In individuals with altered glycemic control, statins increased HbA1c levels (MD 0.21%, 95% CI 0.16-to-0.25) and HOMA-IR index (MD 0.31, 95% CI 0.24-to-0.38). In individuals with normal glycemic control, statin increased HbA1c (MD 1.33%, 95% CI 1.31-to-1.35) and HOMA-IR (MD 0.49, 95% CI 0.41-to-0.58) in comparison to the placebo groups. The dose or type of statins did not modulate the diabetogenic effect.

CONCLUSIONS

Statins, slightly but significantly raise indexes of diabetes in individuals with adequate or altered glycemic control. The diabetogenic effect does not seem to be influenced by the type or dosage of statin prescribed.

Do Statins Counteract the Effect of Antidiabetic Drugs? Results of the SCEAD Study

PURPOSE

Diabetes and dyslipidemia are leading causes of mortality and morbidity. According to international guidelines, statins are the cornerstone of treatment in patients with diabetes and/or dyslipidemia. However, statins and antidiabetic agents have opposite pharmacological effects, because statins, particularly atorvastatin and rosuvastatin, impair glucose homeostasis, increasing the risk of new-onset diabetes, whereas antidiabetic drugs improve glycemic homeostasis. The aim of this study was to investigate the effect of atorvastatin, rosuvastatin, and pitavastatin on glucose homeostasis in patients with type 2 diabetes mellitus (T2DM) and dyslipidemia during stable treatment with hypoglycemic drugs.

MATERIALS AND METHODS

The study was conducted as a pilot, prospective, randomized, open label, parallel group with blinded-endpoints (PROBE) study. Of 180 recruited patients with T2DM and dyslipidemia, 131 were randomized to atorvastatin (n=44), rosuvastatin (n=45), and pitavastatin (n=42) and treated for 6 months.

RESULTS

Fasting plasma glucose (FPG) marginally decreased in patients assigned to atorvastatin (-3.5 mg/dL, p=0.42) and rosuvastatin (-6.5 mg/dL, p=0.17), while it decreased much more in patients treated with pitavastatin (-19.0 mg/dL, p<0.001). Mean glycated hemoglobin A1c (HbA1c ) values remained unchanged during treatment with atorvastatin (-0.10%, p=0.53) and rosuvastatin (0.20%, p=0.40), but were significantly reduced with pitavastatin (-0.75%, p=0.01). Atorvastatin, rosuvastatin, and pitavastatin significantly lowered (p<0.001) plasma levels of total cholesterol, low-density lipoprotein-cholesterol, and triglycerides, while high-density lipoprotein-cholesterol (HDL-C) levels increased significantly (p=0.04) only in the pitavastatin group.

CONCLUSION

The results of the present study suggest that pitavastatin affects FPG and HbA1c less than atorvastatin and rosuvastatin in patients with T2DM and concomitant dyslipidemia. Lipid-lowering efficacies were not significantly different among the three statins, with the exception of HDL-C, which increased significantly with pitavastatin. Although the pharmacological mechanism of pitavastatin on glucose homeostasis in patients with T2DM during stable antidiabetic therapy is not known, it can be assumed that pitavastatin has less drug interaction with hypoglycemic agents or that it increases plasma levels of adiponectin.

The relationship between semen factors and unexplained recurrent spontaneous abortion

BACKGROUND

The male factor may contribute to unexplained recurrent spontaneous abortion (URSA). The relationship between semen factors and URSA is largely unknown. The analysis of metabolomics which is broadly acknowledged as the omics closest to the phenotype is suitable for providing assistance in the semen parameters analysis.

METHODS

We conducted a study including couples with URSA and controls which was next combined with a meta-analysis, and finally the study included 2352 subjects on semen parameters and URSA. Metabolomics analysis was conducted to detect semen metabolic factors related to URSA in total of 106 samples including seminal plasma and sperm cells.

RESULTS

The URSA group had significantly lower total sperm count, sperm concentration, motility and normal morphology percentage. Meta-analysis next showed consistent findings. Metabolomics revealed that 4 metabolites and one pathway and 8 metabolites and one pathway were significantly associated with URSA in sperm and seminal plasma, respectively. The combination of ascorbic acid and guanine in seminal plasma and hexadecanedioic acid and pyroglutamic acid in sperm showed ability for URSA prediction.

CONCLUSION

We provided novel insights into semen indices in relation to URSA. Lower sperm number and quality might increase the risk of URSA, and oxidative stress and hormone metabolism in sperm as well as nucleic acid synthesis and oxidative stress in seminal plasma were related to URSA.

Comparative Lipid-Lowering/Increasing Efficacy of 7 Statins in Patients with Dyslipidemia, Cardiovascular Diseases, or Diabetes Mellitus: Systematic Review and Network Meta-Analyses of 50 Randomized Controlled Trials

OBJECTIVE

The drug efficacy may differ among different statins, and evidence from head-to-head comparisons is sparse and inconsistent. The study is aimed at comparing the lipid-lowering/increasing effects of 7 different statins in patients with dyslipidemia, cardiovascular diseases, or diabetes mellitus by conducting systematic review and network meta-analyses (NMA) of the lipid changes after certain statins' use.

METHODS

In this study, we searched four electronic databases for randomized controlled trials (RCTs) published through February 25, 2020, comparing the lipid-lowering efficacy of no less than two of the included statins (or statin vs. placebo). Three reviewers independently extracted data in duplicate. Firstly, mixed treatment overall comparison analyses, in the form of frequentist NMAs, were conducted using STATA 15.0 software. Then, subgroup analyses were conducted according to different baseline diseases. At last, sensitivity analyses were conducted according to age and follow-up duration. The trial was registered with PROSPERO (number CRD42018108799).

RESULTS

As a result, seven statin monotherapy treatments in 50 studies (51956 participants) were used for the analyses. The statins included simvastatin (SIM), fluvastatin (FLU), atorvastatin (ATO), rosuvastatin (ROS), lovastatin (LOV), pravastatin (PRA), and pitavastatin (PIT). In terms of LDL-C lowering, rosuvastatin ranked 1st with a surface under cumulated ranking (SUCRA) value of 93.1%. The comparative treatment efficacy for LDL-C lowering was ROS>ATO>PIT>SIM>PRA>FLU>LOV>PLA. All of the other ranking and NMA results were reported in SUCRA plots and league tables.

CONCLUSIONS

According to the NMAs, it can be concluded that rosuvastatin ranked 1st in LDL-C, ApoB-lowering efficacy and ApoA1-increasing efficacy. Lovastatin ranked 1st in TC- and TG-lowering efficacy, and fluvastatin ranked 1st in HDL-C-increasing efficacy. The results should be interpreted with caution due to some limitations in our review. However, they can provide references and evidence-based foundation for drug selection in both statin monotherapies and statin combination therapies.

Risk of Statin-Induced Hypertransaminasemia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

To assess the effect of statins compared with placebo on the risk of developing hypertransaminasemia.

PATIENTS AND METHODS

We performed a systematic review of electronic databases and included articles published between January 1, 1965, and April 10, 2017. Randomized clinical trials (RCTs) comparing statins vs placebo were included. Odds ratios (ORs) were pooled in random-effect meta-analyses according to established methods recommended by the Cochrane Collaboration.

RESULTS

Seventy-three eligible RCTs, comprising 123,051 patients, were identified. Statins associated with a significantly risk of hypertransaminasemia (OR 1.45; 95% confidence interval [CI], 1.24-1.69; P<.001). Atorvastatin showed the highest odds (OR 2.66; 95% CI, 1.74-4.06; P<.001) followed by rosuvastatin (OR 1.35; 95% CI, 1.06-1.70; P=.01) and lovastatin (OR 1.53; 95% CI, 1.03-2.28; P=.04). Pravastatin, fluvastatin, and simvastatin yielded no statistically different odds compared with placebo.

CONCLUSIONS

A dose-dependent risk of developing hypertransaminasemia occurs in patients taking atorvastatin, rosuvastatin, and lovastatin.

Effect of pravastatin treatment on circulating adiponectin: a meta-analysis of randomized controlled trials

Objective

Pravastatin has been suggested to increase circulating adiponectin in humans. However, results of randomized controlled trials (RCTs) are inconsistent. We aimed to systematically evaluate the influence of pravastatin on circulating adiponectin in humans by performing a meta-analysis of RCTs.

Materials and methods

Studies were identified via systematic searching of PubMed, Embase, and Cochrane’s Library databases. A random effect model was used to pool the results. Meta-regression and subgroup analyses were applied to explore the source of heterogeneity.

Results

Eight RCTs with nine comparisons of 595 participants were included. Pravastatin treatment was associated with a significant increased level of circulating adiponectin as compared with controls (weighted mean difference [WMD] =0.63 µg/mL; 95% CI, 0.17–1.09 µg/mL; P=0.007) with moderate heterogeneity (I2=28%). These results were confirmed by meta-analysis of double-blinded placebo-controlled RCTs (WMD =0.82 µg/mL; P=0.01). Meta-regression analyses indicated that proportions of males in each study were positively correlated with the effect of pravastatin on adiponectin (coefficient: 0.015, P=0.03). Subgroup analyses confirmed that pravastatin significantly increased adiponectin in studies of males (WMD =1.41 µg/mL; P=0.008), but not in those of females (WMD =−0.04 µg/mL; P=0.94).

Conclusion

Pravastatin treatment is associated with increased circulating adiponectin. Gender difference may exist regarding the effect of pravastatin treatment on adiponectin.

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.

The Association of Statin Therapy with Incident Diabetes: Evidence, Mechanisms, and Recommendations

PURPOSE OF REVIEW

Recent studies have demonstrated a higher risk of incident diabetes associated with statin use, causing concern among patients and clinicians. In this review, we will assess the evidence and proposed mechanisms behind statin therapy and its association with incident diabetes. We will then review the current recommendations for statin use in light of this association and suggest next steps for clinicians managing these patients and researchers exploring this phenomenon.

RECENT FINDINGS

The annual risk of developing new-onset diabetes with statin treatment is approximately 0.1%. In comparison, the absolute risk reduction of major coronary events with statin use is approximately 0.42% annually. Statins are associated with the development of incident diabetes, particularly among those with predisposing risk factors for diabetes. However, the benefit of statin use among these patients in preventing major coronary events strongly favors statin use despite its risk of incident diabetes.

Pravastatin improves risk factors but not ischaemic tolerance in obese rats

Statins are effective in management of dyslipidaemia, and a cornerstone of CVD prevention strategies. However, the impacts of their pleiotropic effects on other cardiovascular risk factors and myocardial responses to infarction are not well characterised. We hypothesised that pravastatin treatment in obesity improves lipid profiles, insulin-resistance and myocardial resistance to ischaemia/reperfusion (I/R) injury. Wistar rats were fed a control (C) chow or high carbohydrate and fat diet (HCFD) for 16 weeks with vehicle or pravastatin (prava 7.5 mg/kg/day) treatment for 8 weeks. At 16 weeks HOMAs were performed, blood samples collected and hearts excised for Langendorff perfusions/biochemical analyses. Anti-oxidant activity and proteins regulating mitochondrial fission/fusion and apoptosis were assessed. The HCFD increased body weight (736±15 vs. 655±12 g for C; P<0.001), serum triglycerides (2.91±0.52 vs. 1.64±0.26 mmol/L for C; P<0.001) and insulin-resistance (HOMA- 6.9±0.8 vs. 4.2±0.5 for C; P<0.05) while prava prevented diet induced changes and paradoxically increased lipid peroxidation. The HCFD increased infarct size (34.1±3.1% vs. 18.8±3.0% of AAR for C; P<0.05), which was unchanged by prava in C and HCFD animals. The HCFD decreased cardiac TxR activity and mitochondrial MFN-1 and increased mitochondrial DRP-1 (reducing MFN-1:DRP-1 ratio) and Bax expression, with the latter changes prevented by prava. While unaltered by diet, cytosolic levels of Bax and caspase-3 were reduced by prava in C and HCFD hearts (without changes in cleaved caspase-3). We conclude that obesity, hyper-triglyceridemia and impaired glycemic control in HCFD rats are countered by prava. Despite improved risk factors, prava did not reduce myocardial infarct size, potentially reflecting its complex pleiotropic impacts on cardiac GPX activity and MFN-1, DRP-1, caspase-3 and Bcl-2 proteins.

Combining Potent Statin Therapy with Other Drugs to Optimize Simultaneous Cardiovascular and Metabolic Benefits while Minimizing Adverse Events

Hypercholesterolemia and hypertension are among the most important risk factors for cardiovascular (CV) disease. They are also important contributors to metabolic diseases including diabetes that further increase CV risk. Updated guidelines emphasize targeted reduction of overall CV risks but do not explicitly incorporate potential adverse metabolic outcomes that also influence CV health. Hypercholesterolemia and hypertension have synergistic deleterious effects on interrelated insulin resistance and endothelial dysfunction. Dysregulation of the renin-angiotensin system is an important pathophysiological mechanism linking insulin resistance and endothelial dysfunction to atherogenesis. Statins are the reference standard treatment to prevent CV disease in patients with hypercholesterolemia. Statins work best for secondary CV prevention. Unfortunately, most statin therapies dose-dependently cause insulin resistance, increase new onset diabetes risk and exacerbate existing type 2 diabetes mellitus. Pravastatin is often too weak to achieve target low-density lipoprotein cholesterol levels despite having beneficial metabolic actions. Renin-angiotensin system inhibitors improve both endothelial dysfunction and insulin resistance in addition to controlling blood pressure. In this regard, combined statin-based and renin-angiotensin system (RAS) inhibitor therapies demonstrate additive/synergistic beneficial effects on endothelial dysfunction, insulin resistance, and other metabolic parameters in addition to lowering both cholesterol levels and blood pressure. This combined therapy simultaneously reduces CV events when compared to either drug type used as monotherapy. This is mediated by both separate and interrelated mechanisms. Therefore, statin-based therapy combined with RAS inhibitors is important for developing optimal management strategies in patients with hypertension, hypercholesterolemia, diabetes, metabolic syndrome, or obesity. This combined therapy can help prevent or treat CV disease while minimizing adverse metabolic consequences.

Lipid-lowering efficacy of rosuvastatin

BACKGROUND

Rosuvastatin is one of the most potent statins and is currently widely prescribed. It is therefore important to know the dose-related magnitude of effect of rosuvastatin on blood lipids.

OBJECTIVES

Primary objective To quantify the effects of various doses of rosuvastatin on serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, non-HDL-cholesterol and triglycerides in participants with and without evidence of cardiovascular disease. Secondary objectives To quantify the variability of the effect of various doses of rosuvastatin.To quantify withdrawals due to adverse effects (WDAEs) in the randomized placebo-controlled trials.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) Issue 10 of 12, 2014 in The Cochrane Library, MEDLINE (1946 to October week 5 2014), EMBASE (1980 to 2014 week 44), Web of Science Core Collection (1970 to 5 November 2014) and BIOSIS Citation Index (1969 to 31 October 2014). No language restrictions were applied.

SELECTION CRITERIA

Randomized controlled and uncontrolled before-and-after trials evaluating the dose response of different fixed doses of rosuvastatin on blood lipids over a duration of three to 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility criteria for studies to be included and extracted data. WDAEs information was collected from the placebo-controlled trials.

MAIN RESULTS

One-hundred and eight trials (18 placebo-controlled and 90 before-and-after) evaluated the dose-related efficacy of rosuvastatin in 19,596 participants. Rosuvastatin 10 to 40 mg/day caused LDL-cholesterol decreases of 46% to 55%, when all the trials were combined using the generic inverse variance method. The quality of evidence for these effects is high. Log dose-response data over doses of 1 to 80 mg, revealed strong linear dose-related effects on blood total cholesterol, LDL-cholesterol and non-HDL-cholesterol. When compared to atorvastatin, rosuvastatin was about three-fold more potent at reducing LDL-cholesterol. There was no dose-related effect of rosuvastatin on blood HDL-cholesterol, but overall, rosuvastatin increased HDL by 7%. There is a high risk of bias for the trials in this review, which would affect WDAEs, but unlikely to affect the lipid measurements. WDAEs were not statistically different between rosuvastatin and placebo in 10 of 18 of these short-term trials (risk ratio 0.84; 95% confidence interval 0.48 to 1.47).

AUTHORS' CONCLUSIONS

The total blood total cholesterol, LDL-cholesterol and non-HDL-cholesterol-lowering effect of rosuvastatin was linearly dependent on dose. Rosuvastatin log dose-response data were linear over the commonly prescribed dose range. Based on an informal comparison with atorvastatin, this represents a three-fold greater potency. This review did not provide a good estimate of the incidence of harms associated with rosuvastatin because of the short duration of the trials and the lack of reporting of adverse effects in 44% of the placebo-controlled trials.

Statin induced diabetes and its clinical implications

Statins are one of the most commonly used drugs in the world based on their potential to prevent adverse cardiovascular events. These cholesterol-lowering drugs received a US Food and Drug Administration warning, in February 2012, regarding increased risk of incident diabetes and impaired glycemic control in patients who already have diabetes. The possible association of diabetes with statin therapy has started a wave of discussion in the medical community. A number of meta-analyses conducted in recent years have demonstrated that the association is real although causality has not been proved yet. Individual statins differ with respect to their diabetogenic property; women and elderly persons appear to be at increased risk. Various aspects of statin's adverse effect on glycemic control remain to be explored. As further research in this area continues, physicians might still take some precautions to make risk benefit ratio more favorable for the patients.

How to balance cardiorenometabolic benefits and risks of statins

Statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, are important for preventing adverse cardiovascular events not only in patients with a high risk of vascular disease but also in those with a low risk, by reducing the levels of low-density lipoprotein cholesterol. Statin is associated with deteriorating glucose homeostasis and an increased risk of diabetes mellitus. Moreover, these off-target effects are dose-dependent; it has also been suggested that renal insult can be caused dose-dependently by statin treatment, in contrast to previous studies showing a renoprotective effect. The 2013 American College of Cardiology/American Heart Association guidelines recommend the use of high-intensity statin therapy, and extend its use to more people at risk of vascular diseases. However, a European committee has expressed concerns about the potential side effects of using statins in a large fraction of the population for extended periods. This is true of Asian people, for whom the disease burden from cardiovascular disorders is not as great as among Western ethnic groups. There are still many unanswered questions on how to balance the cardiovascular benefits with the potential renometabolic risks of statins. Therefore, genetic or pharmacogenetic approaches are needed to define who is more vulnerable to developing diabetes mellitus or acute kidney injury. In particular, more information is required regarding the metabolism of statins, and their off-target or unknown actions and overall impact. These different renometabolic effects of statins should help in formulating optimal therapeutic strategies for patients for reducing overall morbidity and mortality and not just those associated with cardiovascular diseases.

Statins and risk of new-onset diabetes mellitus: is there a rationale for individualized statin therapy?

Statins (hydroxymethylglutaryl-coenzyme-A reductase inhibitors) are first-line agents for the management of hyperlipidemia in patients at high risk of cardiovascular (CV) events, and are the most commonly prescribed CV drugs worldwide. Although safe and generally well tolerated, there is growing evidence to suggest that statins are associated with an elevated occurrence of new-onset diabetes mellitus (DM). Recent experimental and clinical data have prompted the US Food and Drug Administration to add information to statin labels regarding the increased risk of development of type 2 DM. The main purpose of this review is to critically discuss the clinical evidence regarding the association of statin use with new-onset DM, the CV benefit/risk ratio with statins, and the rationale for individualized statin therapy.

Differential metabolic actions of specific statins: clinical and therapeutic considerations

SIGNIFICANCE

Statins, the most widely prescribed drugs in clinical practice, mainly act by reducing the plasma level of low-density lipoprotein (LDL)-cholesterol. A shift in redox homeostasis to an imbalance between reactive oxygen species generation and endogenous antioxidant mechanisms results in oxidative stress that has been implicated in the pathogenesis of various diseases, including those of the cardiovascular system. Beyond their efficacy in lowering LDL cholesterol, statins modulate redox systems that are implicated in the development of atherosclerosis, cardiovascular morbidity, and mortality.

RECENT ADVANCES

Differences in specific statins or their dosages result in differential metabolic actions arising from off-target or unknown mechanisms of action that can have important implications for overall patient morbidity and mortality.

CRITICAL ISSUES

A recent meta-analysis and a combined analysis have suggested that high doses of statins increase the risk of developing type 2 diabetes mellitus, but reduce the risk of cardiovascular events. Thus, it is important to consider the cardiovascular and metabolic context and natural history of diseases when choosing a specific statin therapy for optimal individual patient health over the long term.

FUTURE DIRECTIONS

More information is needed regarding the metabolism of statins, and the off-target or unknown actions of statins in affecting insulin resistance and metabolic homeostasis. The differential metabolic effects of specific statins should be considered in formulating optimal therapeutic strategies to reduce not just cardiovascular-related but also overall patient morbidity and mortality.

Statins and renin-angiotensin system inhibitor combination treatment to prevent cardiovascular disease

Hypercholesterolemia and hypertension are common risk factors for cardiovascular disease (CVD). Updated guidelines emphasize target reductions of overall cardiovascular risks. Experimental studies have shown reciprocal relationships between insulin resistance (IR) and endothelial dysfunction. Hypercholesterolemia and hypertension have a synergistic deleterious effect on IR and endothelial dysfunction. Unregulated renin-angiotensin system (RAS) is important in the pathogenesis of atherosclerosis and hypertension. Various strategies with different classes of antihypertensive medications to reach target goals have failed to reduce residual CVD risk further. Of interest, treating moderate cholesterol elevations with low-dose statins in hypertensive patients reduced CVD risk by 35-40% further. Therefore, statins are important in reducing CVD risk. Unfortunately, statin therapy causes IR and increases the risk of type 2 diabetes mellitus. RAS inhibitors improve both endothelial dysfunction and IR. Further, cross-talk between hypercholesterolemia and RAS exists at multiple steps of IR and endothelial dysfunction. In this regard, combined therapy with statins and RAS inhibitors demonstrates additive/synergistic effects on endothelial dysfunction and IR in addition to lowering cholesterol levels and blood pressure when compared with either monotherapy in patients. This is mediated by both distinct and interrelated mechanisms. Therefore, combined therapy with statins and RAS inhibitors may be important in developing optimal management strategies in patients with hypertension, hypercholesterolemia, diabetes, metabolic syndrome, or obesity to prevent CVD.  

Combination pravastatin and valsartan treatment has additive beneficial effects to simultaneously improve both metabolic and cardiovascular phenotypes beyond that of monotherapy with either drug in patients with primary hypercholesterolemia

Statin and angiotensin II type 1 receptor blocker therapy improves endothelial dysfunction using distinct mechanisms. We evaluated simultaneous vascular and metabolic responses to pravastatin and valsartan therapy, alone or in combination, in hypercholesterolemic patients. Forty-eight hypercholesterolemic patients (23 had metabolic syndrome) were given pravastatin 40 mg and placebo, pravastatin 40 mg and valsartan 160 mg, or valsartan 160 mg and placebo daily during each 2-month treatment period in a randomized, single-blind, placebo-controlled, crossover trial with three treatment arms and two washout periods (each 2 months). Brachial artery flow-mediated dilation and C-reactive protein improved to a greater extent with combined therapy compared with either monotherapy. Importantly, we also observed simultaneous improvement in metabolic phenotypes, with all three treatments causing increased plasma adiponectin levels, reduced fasting insulin levels, and increased insulin sensitivity relative to baseline measurements. For the first time in a statin combination trial, pravastatin combined with valsartan therapy increased plasma adiponectin, lowered fasting insulin levels, and improved insulin sensitivity in an additive manner when compared with monotherapy alone. In contrast to other statins, hydrophilic pavastatin may be combined with other drugs to safely reach lipid target levels while simultaneously improving the metabolic and cardiovascular phenotype of patients at high risk.

Rosuvastatin does not affect fasting glucose, insulin resistance, or adiponectin in patients with mild to moderate hypertension

The effects of statins on insulin resistance and new-onset diabetes are unclear. The purpose of this study was to evaluate the effects of rosuvastatin on insulin resistance and adiponectin in patients with mild to moderate hypertension. In a randomized, prospective, single-blind study, 53 hypertensive patients were randomly assigned to the control group (n=26) or the rosuvastatin (20 mg once daily) group (n=27) during an 8-week treatment period. Both groups showed significant improvements in systolic blood pressure and flow-mediated dilation (FMD) after 8 weeks of treatment. Rosuvastatin treatment improved total cholesterol, low-density lipoprotein (LDL)-cholesterol, and triglyceride levels. The control and rosuvastatin treatment groups did not differ significantly in the change in HbA1c (3.0±10.1% vs. -1.3±12.7%; p=0.33), fasting glucose (-1.3±18.0% vs. 2.5±24.1%; p=0.69), or fasting insulin levels (5.2±70.5% vs. 22.6±133.2%; p=0.27) from baseline. Furthermore, the control and rosuvastatin treatment groups did not differ significantly in the change in the QUICKI insulin sensitivity index (mean change, 2.2±11.6% vs. 3.6±11.9%; p=0.64) or the HOMA index (11.6±94.9% vs. 32.4±176.7%; p=0.44). The plasma adiponectin level increased significantly in the rosuvastatin treatment group (p=0.046), but did not differ significantly from that in the control group (mean change, 23.2±28.4% vs. 23.1±27.6%; p=0.36). Eight weeks of rosuvastatin (20 mg) therapy resulted in no significant improvement or deterioration in fasting glucose levels, insulin resistance, or adiponectin levels in patients with mild to moderate hypertension.

Potentially important considerations in choosing specific statin treatments to reduce overall morbidity and mortality

Hypercholesterolemia and dyslipidemia are independent risk factors for cardiovascular disease and death. Statins are the drugs of choice to decrease plasma cholesterol and have other beneficial actions beyond lipid-lowering leading to substantial improvements in cardiovascular morbidity and mortality. However, evaluation of the effects of statins to reduce overall morbidity and mortality must integrate metabolic consequences of statin therapy with its lipid-lowering effect. Indeed, reduction in LDL-cholesterol to target level achieved by statins does not completely eliminate risk of cardiovascular disease and may elevate metabolic risk factors that contribute to dysregulation of metabolic homeostasis. This may lead to increased incidence of diabetes and its cardiovascular complications that are explained, in part, by reciprocal relationships between insulin resistance and endothelial dysfunction. Genetic factors may determine 40-60% of total cholesterol levels and 70% of the efficacy of statin treatments. Metabolic and cardiovascular phenotypes that are either genetically determined or environmentally acquired are also important determinants of responses to specific statins. Moreover, differences between biological outcomes of specific statins or increasing dosages of statins result in differential metabolic actions due to off-target or unknown mechanism that have important implications for the use of statins to reduce overall morbidity and mortality. In this review, we discuss differential cardiovascular and metabolic pleiotropic actions of specific statins that interact in a context-dependent manner with patient phenotypes and genotypes. These important considerations may influence progression of atherosclerosis, risk of diabetes, and modulation of insulin resistance that help determine overall morbidity and mortality in patients undergoing statin therapy.

High HbA1c levels correlate with reduced plaque regression during statin treatment in patients with stable coronary artery disease: results of the coronary atherosclerosis study measuring effects of rosuvastatin using intravascular ultrasound in Japanese subjects (COSMOS)

Background

The incidence of cardiac events is higher in patients with diabetes than in people without diabetes. The Coronary Atherosclerosis Study Measuring Effects of Rosuvastatin Using Intravascular Ultrasound in Japanese Subjects (COSMOS) demonstrated significant plaque regression in Japanese patients with chronic coronary disease after 76 weeks of rosuvastatin (2.5 mg once daily, up-titrated to a maximum of 20 mg/day to achieve LDL cholesterol <80 mg/dl).

Methods

In this subanalysis of COSMOS, we examined the association between HbA1c and plaque regression in 40 patients with HbA1c ≥6.5% (high group) and 86 patients with HbA1c <6.5% (low group).

Results

In multivariate analyses, HbA1c and plaque volume at baseline were major determinants of plaque regression. LDL cholesterol decreased by 37% and 39% in the high and low groups, respectively, while HDL cholesterol increased by 16% and 22%, respectively. The reduction in plaque volume was significantly (p = 0.04) greater in the low group (from 71.0 ± 39.9 to 64.7 ± 34.7 mm³) than in the high group (from 74.3 ± 34.2 to 71.4 ± 32.3 mm³). Vessel volume increased in the high group but not in the low group (change from baseline: +4.2% vs −0.8%, p = 0.02). Change in plaque volume was significantly correlated with baseline HbA1c.

Conclusions

Despite similar improvements in lipid levels, plaque regression was less pronounced in patients with high HbA1c levels compared with those with low levels. Tight glucose control during statin therapy may enhance plaque regression in patients with stable coronary disease.

Trial registration

ClinicalTrials.gov, Identifier NCT00329160