Does aggressive statin therapy offer improved cholesterol-independent benefits compared to conventional statin treatment?

Intensity-Dependent Benefit of Statins in Survival Among Prospective Kidney Transplant Patients

Statin use in patients listed for in kidney transplant is believed to be beneficial. However, the optimum statin dose for improved survival in this high-risk population is unknown. Our study aimed to determine the impact of prekidney transplant statin dosage on survival postkidney transplant. In this retrospective cohort study, we enrolled patients who underwent kidney transplant from January 2005 to September 2015 at Rush University Medical. Data on the statin use and intensity used before kidney transplant were obtained. The patient population was stratified into 2 groups based on prekidney transplant use of statins. Patients using any form of statin, without regard to the type and dose, were placed in the statin groups, whereas the rest were categorized as the no statin group. The statin group was further classified into low-intensity, moderate-intensity, and high-intensity statin subgroups based on the present atherosclerotic cardiovascular disease definition of statin intensity. The primary outcome was patient survival after kidney transplant. A total of 687 patients had data on statin use before kidney transplant were followed. Median follow-up time was 3.4 years (interquartile range 1.2 to 5.6 years). Multivariate analysis showed that the use of statins prekidney transplant was associated with improved survival postkidney transplant compared with prestatin group (Hazard ratio 0.56, confidence intervals 0.32 to 1.00, p = 0.05). When patients on statins were stratified by statin intensity, Kaplan-Meier survival analysis revealed a significant dose-dependent improvement in survival. Multivariate analysis showed that the relation between statin intensity and survival was maintained even after adjusting for confounder (hazard ratio 0.30, confidence intervals 0.18 to 0.51, p <0.001). In conclusion, our data indicate statistically significant survival benefit in patients receiving high-intensity statin before kidney transplant.

Prescription of lipophilic statins to Alzheimer's disease patients: some controversies to consider

Alzheimer's disease (AD) is the most common disorder causing cognitive decline in old age. It is a progressive and irreversible neuropathology with a diagnosis often missed or delayed. Cholesterol represents an important determinant of the physical state of biological membranes and in AD brains, specific changes in its membrane-ordering and Raft-organizing effects take place. A recent publication shows downregulation of Seladin-1 (selective Alzheimer's disease indicator, also called DHCR24), which catalyzes the last step of cholesterol biosynthesis in affected neurons in AD. Postmortem analysis of AD brains revealed a loss in membrane cholesterol content and this finding makes the therapeutical use of statins (especially the lipophilic ones) quite a lot controversial. Some clinical studies suggest that risk of Alzheimer's disease is substantially reduced in users of statins; however, because these studies are not randomized trials, they provide insufficient evidence to recommend statin family therapy.

Improved survival of diabetic foot ulcer patients 1995-2008: possible impact of aggressive cardiovascular risk management

OBJECTIVE

The purpose of this study was to determine whether a strategy of aggressive cardiovascular risk management reduced the mortality associated with diabetic foot ulceration.

RESEARCH DESIGN AND METHODS

After an initial audit of outcomes demonstrating a high mortality rate in 404 diabetic foot ulcer patients with the first ulceration developing between 1995 and 1999, a new aggressive cardiovascular risk policy was introduced as standard practice at the Diabetic Foot Clinic, Royal Infirmary of Edinburgh, in 2001. In the first 3 years of this policy, 251 patients were screened and identified. The audit cycle was then closed by reauditing the 5-year mortality for this second group of foot ulcer patients in 2008.

RESULTS

Overall 5-year mortality was reduced from 48.0% in cohort 1 to 26.8% in cohort 2 (P < 0.001). Improvement in survival was seen for both neuroischemic patients (5-year mortality of 58% reduced to 36%; relative reduction 38%) and neuropathic patients (36% reduction to 19%; relative reduction 47%) (both P < 0.001). Patients were more likely to die if they were older at the time of ulceration or had type 2 diabetes, renal impairment, or preexisting cardiovascular disease or were already taking aspirin. Prior statin use, current smoker or ex-smoker status, blood pressure, A1C, and total cholesterol were not significantly different between survivors and those who died in the follow-up periods.

CONCLUSIONS

Diabetic foot ulcer patients have a high risk of death. Survival has improved over the past 13 years. The adoption of an aggressive cardiovascular risk management policy in diabetic foot ulcer clinics is recommended for these patients.

Effects of simvastatin and metformin on inflammation and insulin resistance in individuals with mild metabolic syndrome

BACKGROUND

In addition to lipid-lowering and insulin-sensitizing actions, statins (HMG-CoA reductase inhibitors) and metformin may have pleiotropic effects.

OBJECTIVE

To study the effect of simvastatin and metformin on insulin sensitivity and inflammatory markers.

METHODS

Forty-one subjects with body mass index (BMI) 25-39.9 kg/m(2) and impaired glucose tolerance were randomized to receive simvastatin or metformin for 16 weeks. Blood samples were obtained for measurement of metabolic and inflammatory parameters before and after each treatment.

RESULTS

As expected, when compared with simvastatin, metformin therapy resulted in significant reductions in mean BMI, fasting plasma glucose, and homeostasis model assessment-insulin resistance (HOMA-IR), whereas simvastatin treatment resulted in significantly reduced total cholesterol, low-density lipoprotein-cholesterol (LDL-C), and apolipoprotein B levels. Independently of the medication used, significant decreases in C-reactive protein (CRP) and interleukin (IL)-6 were detected from baseline to treatment end. CRP showed a mean reduction of 0.12 +/- 0.04 mg/dL (p = 0.002) over the 16-week intervention period and IL-6 a mean reduction was 0.35 +/- 0.17 pg/mL (p = 0.046). No change was observed in the tumor necrosis factor-alpha levels. Baseline values of CRP and IL-6 and their percentage declines were correlated (r = 0.71 and r = 0.67, respectively; p < 0.001). In simvastatin recipients, no correlation was detected between reductions in CRP or IL-6 and lipids, whereas in metformin recipients, reductions in inflammatory markers were not correlated to BMI and HOMA-IR.

CONCLUSION

Our findings suggest that both metformin and simvastatin have similar beneficial effects on low-grade inflammation, in addition to their classical effects on glucose and lipid metabolism. Moreover, they confirm the importance of treating at-risk individuals even before the precipitation of overt diabetes mellitus or full-blown metabolic syndrome.

Atorvastatin Treatment in the Short Term: Does It Induce Renoprotection or Vasculoprotection in Renal Transplantation?

INTRODUCTION

Proteinuria and dyslipidemia are nonimmune risk factors implicated in the deterioration of kidney function and associated with an increased risk of accelerated atherogenesis. Statin therapy, used for cholesterol reduction, has shown a renoprotective effect in animal models, particularly in cases of proteinuria. This may occur through lipid-independent mechanisms, such as improved endothelial dysfunction/vascular biology, reduced inflammatory cytokine production (transforming growth factor-beta 1 [TGF-beta1]), and regulation of fibrogenic responses. We studied mechanisms of action of agents, such as statins, to change proteinuria, inflammatory parameters, and TGF-beta1 plasma levels in relation to vascular tone.

METHODS

Fifty-six kidney transplant recipients (30 men and 26 women of overall mean age 54 +/- 13 years) were treated posttransplantation with atorvastatin (10 mg/d) for 12 weeks without renin-angiotensin-system blockade drugs. Inflammatory variables, biochemical parameters, lipid profile, renal function, and TGF-beta1 levels were determined at baseline and at 3 months. Vascular stiffness was evaluated using pulse wave velocity (PWV).

RESULTS

Baseline TGF-beta1 plasma levels were higher among transplant recipients than healthy controls, namely 8.12 ng/mL (range, 5.82-13.12) to 2.55 (range, 1.78- 4.35) (P < .01). Furthermore, the levels remained higher after the treatment with atorvastatin, namely, 7.59 (range, 4.97-12.35) to 2.55 (range, 1.78-4.35) ng/mL (P < .01). Atorvastatin treatment significantly decreased total cholesterol as well as low-density lipoprotein cholesterol plasma levels, but did not modify mean blood pressure (MBP), proteinuria, creatinine clearance, or inflammatory factors. Reduction in TGF-beta1 plasma levels was statistically significant among patients with PWV >9.75 (m/s) (pathology reference value) namely, from 10.7 ng/mL (range, 7.02-13.98) to 6.7 (range, 3.96-11.94) (P = .038). Among older patients, atorvastatin significantly decrease TGF-beta1 plasma levels: from 9.5 ng/mL (range, 6.45-14.44) to 5.65 (range, 3.63-9.48; P < .05). The decreased TGF-beta1 was not related to changes in lipid profiles.

CONCLUSIONS

Atorvastatin (10 mg/d) improved the lipid profile and moreover among older patients with worse PWV (>9.75 m/s), TGF-beta1 levels were significantly reduced. Our results suggested that statins displayed potent actions distinct from their hypolipidemic effects.

High-dose statin treatment does not alter plasma marker for brain cholesterol metabolism in patients with moderately elevated plasma cholesterol levels

Statins inhibit endogenous cholesterol synthesis, up-regulate low-density lipoprotein (LDL) receptor expression in mammalian liver cells, and thus decrease circulating LDL-cholesterol concentrations. As cholesterol seems to play a role in the development of neurodegenerative diseases, it is of interest to evaluate the effect of high dosages of statins (eg, atorvastatin or simvastatin) on brain cholesterol metabolism. Plasma samples from 44 participants (aged 30-69 years, 16 men and 18 women) of an earlier randomized, placebo-controlled, double-blind trial, who took 40 mg atorvastatin or 80 mg simvastatin daily for 2 months, were used to analyze total cholesterol, its precursor lathosterol, and its metabolites 24(S)-hydroxycholesterol and 27-hydroxycholesterol. Despite a significant decrease in absolute plasma concentrations of oxysterols, total cholesterol, and its endogenous synthesis rate, indicated by a decreased ratio of lathosterol to cholesterol, the plasma 24(S)-hydroxycholesterol to cholesterol ratio, a surrogate marker of brain cholesterol homeostasis, remained unchanged. Short-term high-dose atorvastatin and simvastatin treatment does not seem to influence brain cholesterol metabolism in patients with moderately elevated plasma cholesterol levels.

Effect of low doses of atorvastatin on adiponectin, glucose homeostasis, and clinical inflammatory markers in kidney transplant recipients

INTRODUCTION

Various studies describe the pleiotropic antiinflammatory and antioxidant effects of atorvastatin, in addition to its hypolipemic effects. It has been suggested that statins modify glucose homeostasis via their antiinflammatory effects. A further hypothesis suggests that the incidence of posttransplantation diabetes is lower in statin-treated patients. This study sought to ascertain whether atorvastatin modifies glucose homeostasis, adiponectin, and inflammatory markers in kidney transplant recipients.

PATIENTS AND METHODS

Sixty-eight kidney transplant recipients (41 men, 27 women; mean age, 53 +/- 12 years) with stable renal function and dyslipidemia were treated with atorvastatin (10 mg/d) for 12 weeks. Glucose, insulin, homeostasis model assessment (HOMA-IR) index, adiponectin, tumor necrosis factor (TNF)-alpha, and serum C-reactive protein (CRP) concentrations were determined at baseline and at 3 months. The lipid profile, renal function parameters (creatinine, creatinine clearance, and proteinuria), as well as GOT, GPT, and CK were determined at baseline and at 3 months.

RESULTS

Treatment with atorvastatin achieved a statistically significant decrease in lipid profile. After 3 months of treatment, 74.6% of patients had total cholesterol and 78.7% low-density lipoprotein (LDL) cholesterol concentrations within reference range (<5.2 and 3.3 mmol/L, respectively). Furthermore, 47.5% of patients attained an LDL concentration <2.59 mmol/L. A greater reduction in total cholesterol (P = .05) and LDL cholesterol (P = .04) was achieved in patients with creatinine clearance <60 mL/min. Atorvastatin did not modify glucose homeostasis parameters, adiponectin, TNF-alpha, or CRP. At baseline and after 3 months of treatment, an inverse correlation was found between adiponectin and glucose, insulin, HOMA- IR index, and creatinine clearance, and a positive correlation was found between adiponectin and high-density lipoprotein (HDL) cholesterol.

CONCLUSION

Atorvastatin at a dose of 10 mg/d in kidney transplant recipients does not modify glucose homeostasis or alter inflammatory markers, despite its hypolipemic effects. Its efficacy to reduce total cholesterol and LDL cholesterol was greater in patients with worse renal function.

Beneficial effect of simvastatin and pravastatin treatment on adverse cardiac remodelling and glomeruli loss in spontaneously hypertensive rats

The aim of the present study was to investigate the possibility of different effects of the hydrophobic statin simvastatin and the hydrophilic statin pravastatin on the remodelling process in the overloaded left ventricle and renal cortex of SHRs (spontaneously hypertensive rats). Fifteen SHRs were treated for 40 days with simvastatin, pravastatin or placebo (water) via orogastric administration. Left ventricle and renal cortex were examined by light microscopy and stereology. LV (left ventricular) cardiomyocyte nuclei (N[cmn]) and glomeruli (N[gl]) numbers were estimated by the dissector method. BP (blood pressure) and serum triacylglycerols (triglycerides) were lower in the statin-treated groups than in the untreated control group. The volume density of the interstitial connective tissue was smaller and length density of the intramyocardial arteries, as well as the arteries/cardiomyocyte ratio, was greater in the statin-treated groups than in the control group. No difference was observed between the two statin-treated groups. The cross-sectional cardiomyocyte area was significantly smaller in the simvastatin-treated group than in the control or pravastatin-treated groups, and it was smaller in the pravastatin-treated group than in the control group. N[cmn] and N[gl] were greater in the two statin-treated groups than in the control group, but no significant difference was observed between the two statin-treated groups. In conclusion, administration of the statins simvastatin and pravastatin to SHRs effectively prevented the elevation in BP and serum triaclyglycerols, and also attenuated adverse cardiac and kidney remodelling by preventing LV hypertrophy, enhancing myocardial vascularization with the decrease in interstitial fibrosis and attenuating cardiomyocyte and glomerular loss.