Researchers at Johns Hopkins may have discovered an unintended benefit in the drugs millions of Americans take to lower their cholesterol: The medications, all statins, seem to lower the risk of a potentially lethal blood infection known as sepsis in patients on kidney dialysis.

The study is published in the current issue of the Journal of the American Medical Association (JAMA).

Sepsis is the leading cause of death in non-coronary intensive care units in the United States, according to the U.S. Centers for Disease Control. It also poses serious risk for kidney patients undergoing regular dialysis treatments.

The Hopkins researchers cautioned that kidney dialysis patients should not necessarily ask their doctors to put them on statins until more studies are done to verify their findings.

Building on earlier, limited studies that suggested risk reduction in animals and some people, Professor of Medicine, Director of the Welch Center and senior author Neil R. Powe, M.D., and his Johns Hopkins team followed 1041 dialysis patients for 10 years, dividing the subjects into those taking statins and those not.

"Those taking statins had a 41 in a 1,000 chance of being hospitalized for sepsis, while the other group not taking statins had a 110 out of 1,000 risk. Although the overall absolute risk is relatively small, the statin group's risk is dramatically lower," says Rajesh Gupta M.D., the study's lead author, who was a senior medical resident at Hopkins when the study was conducted.

Gupta says it remains unclear why or how statins work this way, "but the consistency of the findings with laboratory studies adds a lot of credence to the idea that statins are doing something substantial to reduce risk."

Statins are known to have an effect on the body's immune system, but what that is exactly, and how many statin users it affects, is still not widely understood."

Statins may regulate the immune response to infection or fight microbes directly, Powe suspects. The study's authors also suppose that statins may work like penicillin, since the first statin was originally derived from a fungus which, it is theorized, secretes a statin as a way to starve other competing microorganisms that require cholesterol to survive.

The study included patients from 81 dialysis clinics across 19 states. Only those enrollees who were admitted to the hospital with sepsis were counted, in order to rule out any subjects who became septic during an unrelated hospital stay.

Only 14 percent of those initially enrolled in the study were on statins. Out of the 1,041 patients, there were a total of 303 hospitalizations for sepsis.