New investigation links common cholesterol drugs to kidney damage
Older patients taking a class of cholesterol medicines known as fibrates may be at risk for kidney damage, finds a new investigation. Scientist at the Lawson Health Research Institute and the Institute for Clinical Evaluative Sciences (ICES), and colleagues, found that one in ten older patients who take the cholesterol drugs experience a 50% rise in their serum creatinine, which is a kidney function test. A serum creatinine test only rises when half of the kidney nephrons (filters) are damaged.
High cholesterol treatment with fibrates works primarily by lowering lipids (fats) in the blood stream known as triglycerides that could contribute to heart disease. The drugs do little to lower bad or LDL cholesterol levels. They work on the liver to reduce the number of triglycerides manufactured in the body as well as speeding the rate triglycerides are cleared from the bloodstream. If they are used long-term they can cause gallstones. Examples of the common cholesterol drugs include gemfibrozol (Lopid), and fenofibrate (TriCor, Triglide).
Cholesterol drugs may be of little value for heart health
ABC reported in March 2011 that the use of the drugs has steadily increased, despite hard evidence from clinical trials that they prevent heart attack or stroke.
"The use of fibrates in America is very troubling," said Dr. Steven E. Nissen, chairman of cardiovascular medicine at the Cleveland Clinic Foundation. Noting that fibrates are among medications advertised directly to consumers, he said: "This is a classical example of marketing triumphing over science”, ABC wrote.
For their study, researchers looked at markers of kidney health among 20,000 older residents of Ontario, Canada. Within 90 days of taking the medications, creatinine levels that measure kidney damage were elevated by 50% in one out of ten patients, which had not been reported in studies of the drug. The researchers compared drug results to patients taking ezetimide, which is also not known to have any effect on the kidneys.
"At the end of the day, we want to prescribe medication with the highest benefit and the least amount of adverse events," said Dr. Amit Garg, Scientist at the Lawson Health Research Institute and the Institute for Clinical Evaluative Sciences (ICES) in a news release. "When a physician decides to start a fibrate in a new patient, especially an older patient, given the information we have today they should start the patient on a dose that's appropriate, closely monitor their kidney function, and, if the kidney function goes off, either lower the dose or discontinue the drug."
More studies are needed to understand how fibrates used to lower cholesterol affect kidney health. Dr. Garg, who led the study, is also a Nephrologist and Director of the Kidney Clinical Research Unit at London Health Sciences Centre.
Annals of Internal Medicine
“New Fibrate Use and Acute Renal Outcomes in Elderly Adults”
Ying Y. Zhao, MD, et al.
April 17, 2012
Image credit: Bing