Effects of pravastatin on serum adiponectin levels in female patients with type 2 diabetes mellitus

Comparative effects of pravastatin and rosuvastatin on carbohydrate metabolism in an experimental diabetic rat model

Statin treatment may increase the risk of diabetes; there is insufficient data on how statins affect glucose regulation and glycemic control and the effects of statins on liver enzymes related to carbohydrate metabolism have not been fully studied. Therefore, we aimed to compare the effects of the statin derivatives, pravastatin, and rosuvastatin, on carbohydrate metabolism in an experimental diabetic rat model. Female Wistar albino rats were used and diabetes was induced by intraperitoneal injection of streptozotocin. Thereafter, 10 and 20 mg kg-1 day-1 doses of both pravastatin and rosuvastatin were administered by oral gavage to the diabetic rats for 8 weeks. At the end of the experiment, body masses, the levels of fasting blood glucose, serum insulin, insulin resistance (HOMA-IR), liver glycogen, and liver enzymes related to carbohydrate metabolism were measured. Both doses of pravastatin significantly in creased the body mass in diabetic rats, however, rosuvastatin, especially at the dose of 20 mg kg-1 day-1 reduced the body mass signi ficantly. Pravastatin, especially at a dose of 20 mg kg-1 day-1, caused significant increases in liver glycogen synthase and glucose 6-phosphate dehydrogenase levels but significant decreases in the levels of glycogen phosphorylase, lactate dehydrogenase, and glucose-6-phosphatase. Hence, pravastatin partially ameliorated the adverse changes in liver enzymes caused by diabetes and, especially at the dose of 20 mg kg-1 day-1, reduced the fasting blood glucose level and increased the liver glycogen content. However, rosuvastatin, especially at the dose of 20 mg kg-1 day-1, significantly reduced the liver glycogen synthase and pyruvate kinase levels, but increased the glycogen phosphorylase level in diabetic rats. Rosuvastatin, 20 mg kg-1 day-1 dose, caused significant decreases in the body mass and the liver glycogen content of diabetic rats. It can be concluded that pravastatin, especially at the dose of 20 mg kg-1 day-1 is more effective in ameliorating the negative effects of diabetes by modulating carbohydrate metabolism.

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.

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.

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.

[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.