Atorvastatin Effects On Arterial Stiffness In Hemodialysis

Cardiovascular disease (CVD) is the most common cause of morbidity and mortality among patients with end-stage renal disease (ESRD) on hemodialysis (HD).

CVD are present since the early stages of chronic kidney disease (CKD) and reach around 30 to 44% of those beginning hemodialysis. Macrovascular disease develops rapidly in uremic patients and is responsible for the high incidence of ischemic heart disease, left ventricular (LV) hypertrophy, congestive heart failure, sudden death, and stroke.

Compared with the general population, the incidence of cardiovascular (CV) events among patients with ESRD is significantly higher, but it does not seem to be fully explained by the increased incidence of conventional risk factors alone. It has been hypothesized that HD patients are exposed to unique renal and HD-related risk factors that predispose them to an increased rate of CV events. Research efforts have expanded understanding of the contribution made by vascular pathologies to this burden.

Clinicians now recognize that defects in the vascular wall are the bases of many CV events, and early detection and intervention in subclinical vascular disease are fundamental for preventing and controlling cardiovascular events. Changes in the vasculature include endothelial dysfunction (ED), smooth muscle cell hyperplasia/hypertrophy, vascular calcification, and arterial stiffness.

Arterial stiffness is one of the vascular pathologies in HD patients. Recent studies examining cardiovascular complications in dialysis patients focused on atherosclerosis, including arterial stiffness and wall thickness changes as a major contributing factors for CV events. It was shown that stiffening of arteries is associated with increased cardiovascular mortality and morbidity.

Arteriosclerosis refers to the reduced arterial compliance due to increased fibrosis, loss of elasticity, and vessel wall calcification affecting the media of large and middle-sized arteries. These arterial wall changes are influenced not only by nonspecific factors, such as age, genetics, hypertension, diabetes, lipid abnormalities, inflammation, and/or common atherosclerosis, but also by parameter(s) associated with the presence of uremia per se.

Arterial stiffening in patients with CKD and ESRD occurs at an accelerated rate compared with the normal ageing process and arteriosclerosis. As bone mineral metabolism worsens with advancement to ESRD, hyperphosphatemia, secondary hyperparathyroidism and inhibited vitamin D synthesis result in vascular calcification that causes hardening of the arteries. Other factors linked to the uremic environment, such as anaemia, endothelial dysfunction, neuro-hormonal activation and inflammation, play important roles.

Arterial stiffness can be assessed noninvasively with the use of pulse wave velocity (PWV) measurement. The aortic pulse wave velocity (APWV) reflects central arterial stiffness. APWV is a predictor of cardiovascular outcome in patients with hypertension, diabetes, end-stage renal disease, and elderly hospitalized subjects.

Statins or 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors are considered first-line treatment for elevated low-density lipoprotein cholesterol (LDL-C) levels, as large-scale, randomized clinical trials have demonstrated their clinical benefits in primary and secondary prevention of cardiovascular events. Background and clinical studies have also shown beneficial actions of statins for the vasculature that may extend above their lipid lowering properties, such as improvement of endothelial function, inhibition of vascular smooth muscle cell proliferation, and reduction of vascular inflammation. It has been also proposed that such pleiotropic effects of statins may translate into a beneficial impact on arterial stiffness. Atorvastatin reduced arterial stiffness in patients with hypertension and hypercholesterolemia, diabetes mellitus. Fassett at al. found that atorvastatin reduced arterial stiffness in CKD patients (stage 2-4) but they did not include patients on maintenance haemodialysis in their study. We want to illustrate if these beneficial effects on arterial stiffness will be present or not among haemodialysis patients.

Inclusion criteria

• Patients on regular hemodialysis treatment for more than 3 months

Exclusion criteria

• Patients with diabetes mellitus.
• Patients with known severe valvular heart disease.
• Irregular heart rhythm.
• History of aortic surgery/prosthetic aorta.
• Acute liver disease.
• Patients receiving lipid lowering drugs.
• Pregnancy.
• History of myocardial infraction in the previous 6 months.