Long-term use of statins, a drug widely prescribed to prevent artery-blocking cholesterol, is less risky than thought for patients with a common form of liver disease, according to a study published on Wednesday by The Lancet.
Statins work by blocking a liver enzyme that makes fatty molecules which line arterial walls and boost the danger of heart disease and strokes.
Doctors commonly choose not to prescribe these drugs to people with high levels of a type of liver enzyme which is often a telltale of non-alcoholic fatty liver disease, or NAFLD.
Few studies have until now been carried out into the benefits or risks of this policy, and the probes have been small and short-term.
In the biggest and longest investigation of its kind, doctors in Greece enrolled 437 patients who had abnormal liver function tests and were believed to have NAFLD.
Of these, 227 of whom were treated with a statin, while the others were not treated.
Over the three-year duration of the study, 10 percent of patients in the statin group had a heart attack or a stroke, while in the non-statin group, this was 20 percent. The benefit for the statin group was a relative risk reduction of more than two-thirds.
Bouts of liver-related sickness were equal in both groups, indicating no adverse affects on the liver from taking statins.
The study was led by Vasilis Athyros from the Hippokration University Hospital in Thessaloniki, Greece and Dimitri Mikhailidis from University College London, London.
Commenting on the study, Ted Bader from the University of Oklahoma Health Sciences Center said the findings demonstrated emphatically that many patients with liver disease had been wrongly denied statins for high cholesterol for too long.
"Most physicians believe that statins cause liver disease because of the language of package inserts. Drug companies should be encouraged to request the deletion of this point from the insert," he said.
Statins have been dubbed "the aspirin of the 21st century" for their perceived benefits in cardiovascular health and relatively few side effects. Worldwide sales total more than 20 billion dollars annually.
A study published last week cautioned against over-prescribing, saying that among healthy adults, only those with measurable buildup of artery-hardening calcium would significantly benefit.
The six-year study found that 75 percent of all heart attacks, strokes or heart-related deaths occurred in the 25 percent of participants who had the highest calcium buildup in their blood vessels.
The 47 percent of participants who had no detectable levels of calcium buildup meanwhile suffered just five percent of heart disease-related events, meaning the therapy would have offered little protection.
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