CORVALLIS, Ore. - A new analysis of kidney dialysis patients by an Oregon State University researcher suggests they may not be good candidates for statins, a widely used class of drugs for lowering high cholesterol.
After analyzing the findings from three large, well-designed clinical studies, pharmacist Ali Olyaei cautions that statins provide only minimal cholesterol control for dialysis patients while posing elevated dangers of toxicity and adverse drug interactions. Particularly at risk are elderly and diabetic patients.
"Statins are the current drugs of choice for high cholesterol," said Olyaei, a professor in the OSU College of Pharmacy and at Oregon Health and Science University. "However, they should be used with caution for primary prevention of cardiovascular disease in dialysis patients who are at great risk of toxicity and drug interactions."
The three studies - which together followed more than 13,000 patients in the United States and 24 other countries - examined the effectiveness and safety of statins for chronic kidney disease, transplantation and dialysis patients. The studies found that dialysis patients who took statins were just as likely to die from heart attacks, strokes or other causes as were those who did not take statins, said Olyaei, who specializes in renal and transplant medicine at the OSU/OHSU Division of Nephrology and Hypertension in Portland.
In fact, some dialysis patients taking certain statins had higher rates of fatal stroke than patients taking a placebo.
Olyaei, in a guest editorial for the journal Dialysis & Transplantation, explained that the three studies suggest a "very limited role" for statins in preventing high cholesterol and heart disease for dialysis patients.
"Therefore," he concluded, "three strikes and statins are out for the primary prevention of cardiovascular disease in dialysis patients."
While noting that statins have proven very effective for reducing cholesterol in the general population, Olyaei stressed the complexity of disease processes that go hand-in-hand with kidney failure. Researchers are still trying to understand the interplay of factors - including inflammation, malnutrition and cardiovascular disease - that affect the absorption, metabolism and therapeutic value of medications among patients with chronic kidney disease, dialysis patients among them.
It is this complex interplay of biological and pharmaceutical interactions that doctors and pharmacists must consider in prescribing and dosing. For example, some pharmaceutical guidelines recommend reducing dosages by 50 percent for some statins in later stages of kidney disease, according to Olyaei.
"Statins have been proven to be safe and well-tolerated by the majority of patients, but this class of drugs is not entirely free of adverse drug reactions," said Olyaei in the Clinical Journal of the American Society of Nephrology. "Patients with chronic kidney disease are at increased risk of these adverse effects and should be monitored carefully for tolerability and toxicity. All of the statins should be used with caution in patients with impaired renal function."
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Ali Olyaei, 503-494-1308 or 503-494-8132