Statins in Proteinuric Nephropathies

INTRODUCTION End stage renal disease (ESRD) is rapidly growing worldwide and costs of providing ESRD care will soon outstrip the available resources. In addition to a poor quality of life, patients with ESRD have 10 to 20 timer higher mortality than age-, race- and gender-matched healthy controls, with > 50% of this excess burden being attributable to cardiovascular risk. Thus, preventing or limiting progression of chronic nephropathies, may serve to limit the incidence not only of ESRD, but also the excess of cardiovascular complications associated with chronic renal disease.

Several data are available that proteinuria is an important determinant of progression to ESRD and a risk factor for increased cardiovascular morbidity and mortality. Drugs, such as Angiotensin-Converting-Enzyme inhibitors (ACEi) and Angiotensin II receptor antagonists (ATA), that decrease proteinuria are also reno- and cardio-protective in the long-term.The combination of these drugs may reduce proteinuria more effectively than the two drugs alone. Preliminary data are also available that statins, in addition to ameliorate the lipid profile may have specific renoprotective properties and, combined to ACEi and ATA, may synergize their antiproteinuric effects in experimental models of chronic renal disease.Moreover, the addition of statins to antihypertensive treatment with or without inhibitors of the renin-angiotensin system has an additive effect on reducing proteinuria also in humans.Whether also in humans combining statins to ACEi and ATA may reduce proteinuria more effectively than ACEi and ATA alone is therefore worth investigating.

AIMS Primary

• To assess whether statins combined to ACEi and ATA more effectively than ACEi and ATA alone reduce urinary protein excretion rate in chronic proteinuric nephropathies.

Secondary

• To assess the effect of statins combined to ACEi and ATA vs. the combination of ACEi and ATA alone on other outcome variables including urinary protein/creatinine ratio, glomerular filtration rate (GFR), lipid profile and, in a subgroup endothelial function. - To evaluate by correlation and multivariate analyses the relationship between baseline /follow-up covariates and the above outcome variables in the study group as a whole and within each treatment group.
• To assess treatment tolerability DESIGN This is be a prospective, randomized, parallel group study in which, following a 2 month Wash-out period from previous treatment (if any) with ACEi, ATA, potassium sparing diuretics or statins, patients will enter a two-month Run-In phase on renin angiotensin system (RAS) inhibitor therapy (ACE inhibition by benazepril for one month and ACE inhibition plus angiotensin II antagonism by combined treatment with benazepril and valsartan for one further month). At completion of the Run-in period and after a baseline evaluation, patients will be randomized to a six-month Treatment period with or without fluvastatin. Regardless of the randomization group, all patients will be offered optimal conservative treatment including optimal blood pressure control(systolic/diastolic blood pressure <130/80 mmHg) and life-style recommendations such as stop smoking and controlled protein and sodium intake.

180 patients will be enrolled in the study.

Inclusion criteria

• age >16 years
• hypertension, defined as a systolic or diastolic blood pressure > 140 or 90 mmHg respectively (or less in patients with concomitant antihypertensive therapy)
• creatinine clearance >20 ml/min/1.73m2 (with variation of less than 30% in the 3 months prior to study entry)
• urinary protein excretion rate persistently > 1 g/24 hours (average of at least two measurements in two urine collections two weeks apart) without evidence of urinary tract infection or overt heart failure (New York Heart Association class III or more)
• written informed consent

Exclusion criteria

• specific contraindication to statin therapy because of a previous coronary event or serum LDL-cholesterol levels > 190 mg/dL despite a low cholesterol (<200 mg/day) diet and a saturated fatty acid in take less than 7% of total calories will not be included
• chronic treatment with corticosteroids, nonsteroidal anti-inflammatory drugs, or immunosuppressive drugs
• acute myocardial infarction or cerebrovascular accident in the six months preceding the study - severe uncontrolled hypertension (diastolic blood pressure >115 and/or systolic blood pressure >220 mmHg)
• evidence or suspicion of renovascular disease, obstructive uropathy, type 1 diabetes mellitus, vasculitides, cancer
• elevated serum aminotransferase concentrations - chronic cough
• history of poor tolerance or allergy to ACEi, ATA or statins
• drug or alcohol abuse
• pregnancy, breast feeding and ineffective contraception
• legal incapacity and/or other circumstances rendering the patient unable to understand the nature, scope and possible consequences of the trial.