Statin Drugs May Cut Risk of Gallstones

Nov. 11, 2009 -- A popular class of cholesterol-lowering medications appears to reduce the risk for gallstones that ultimately require surgery.

Researchers reporting in this week's issue of TheJournal of the American Medical Association have found that adults who take a statin medication for at least one year are less likely to develop gallstones that result in having the gallbladder removed.  

Most gallstones are made from cholesterol deposits that occur in bile, a fluid that helps break down fats. Bile is stored in the gallbladder and flows through tubes, called ducts, to the small intestine.

Bile naturally contains some cholesterol. But if there is too much cholesterol in bile, gallstones can form. These stones can sometimes block the normal flow of bile out of the gallbladder, leading to severe cramping pain called colic and other gastrointestinal tract symptoms.

Treatment often involves surgery to remove the gallbladder, a procedure called a cholecystectomy. Every year in the U.S., doctors perform more than 700,000 such surgeries.

"Our findings [that statins may lower the risk of cholesterol gallstones] may be of clinical relevance given that gallstone disease represents a major burden for health care systems," Michael Bodmer, MD, MS, of University Hospital in Basel, Switzerland, and colleagues say in a news release.

For the study, the researchers examined thousands of medical records from a U.K. database for the years 1994-2008, noting how many people took statins and how many had gallstone disease followed by having their gallbladder removed. About 2,400 patients with a history of gallstone disease and surgery had a history of taking statins.  Researchers compared those patients to nearly 8,900 patients of similar age, sex, and health taking statins but who had no history of gallstones or cholecystectomy.

Decreased risk of cholesterol-type gallstones that required surgery was linked to one to 1.5 years of statin treatment. No association was seen with shorter-term use, and the findings were similar for all statins. The benefit appeared to be the same for all age and gender groups, even after adjusting for other important risk factors for gallstone disease such as being overweight or using estrogen. 

"This large observational study provides evidence that patients with long-term statin use have a reduced risk of gallstone disease followed by cholecystectomy compared with patients without statin use," the researchers write.

The dose of the statin appeared to also play a role. Patients who took high-dose statins tended to have a lower risk of gallstone disease than those who took lower doses.