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Reading Exercise 4: Cholesterol People who significantly cut their cholesterol levels with statins may raise the risk of cancer, a study says. The study of 40,000 people found those with little of the “bad” cholesterol LDL saw one more cancer case per 1,000 than those with higher levels. The Boston-based researchers could not say if this was a side-effect of the statin or due to the low cholesterol. They also write in the Journal of the American College of Cardiology that the benefits of statins outweigh the risks. “The analysis doesn’t implicate the statin in creasing the risk of cancer,” says lead author Richard Karas of Tufts University School of Medicine in Boston. “The demonstrated benefits of statins in lowering the risk of heart disease remain clear. However certain aspects of lowering LDL with statins remain controlversial and merit further research.” Researchers looked at the summary data from 13 trials of people taking statins—a total of 41,173 patients. These findings do not change the message that the benefits of taking statins greatly outweigh any potential risks. British Heart Foundation examined the relationship between low, medium and high doses of statins and rates of newly diagnosed cancer. Higher rates of the disease—which were not of any type or location—were observed in the group with the lower levels. The authors noted their findings were particularly important at a time when more and more trials show significant reductions in LDL levels can greatly benefit cardiovascular health. Cancer information officer Dr. Alison Ross said: “The findings of this study should be treated with caution—it is based on summary data from previous trials and, as the authors point out themselves, it does not prove that low LDL cholesterol levels can increase cancer risk. Much more research is needed before any firm conclusions can be made.” The British Heart Foundation said they had long known of a relationship between low cholesterol and cancer. “While this highlights an association between low levels of LDL and cancer, this is not the same as saying that low LDL or statin use increases the risk of cancer,” said June Davison, cardiac nurse. “There is overwhelming evidence that lowering LDL cholesterol through statins saves lives by preventing heart attacks and strokes. These findings do not change the message that the benefits of taking statins greatly outweigh any potential risks.” A major international trial has been set up to see whether a treatment to increase so-called “good” cholesterol can prevent heart attacks and strokes. “Good” cholesterol—high density lipoproteins (HDL)—cuts heart disease risk by removing fat from the circulation. The treatment, designed to increase levels of HDL, will be given alongside drugs to reduce “bad” cholesterol, alongside drugs to reduce “bad” cholesterol, which can raise the risk of disease. A team at Oxford University is leading the trial involving 20,000 volunteers. To be eligible for the trial, patients must be aged between 50 and 80 with a history of heart attack, stroke or peripheral artery disease. Around 7,500 men and women will be recruited from the UK with people from China and Scandinavia making up the rest of the participants. The main ingredient in the trial drug is niacin, which has been found to increase levels of HDL by between a fifth and a quarter as well as decreasing dangerous fatty substances called triglycerides. “The trial will be in people at risk of future heart problems despite the fact that their LDL cholesterol has been lowered,” said Dr. Jane Armitage, trial leader. But patients have found it difficult to take niacin long-term because it produces an uncomfortable side-effect of flushing. To combat this effect, niacin has been combined with another drug, which blocks the release of prostaglandin D2—the substance which produces the flushing effect. The team at the Clinical Trials Unit at Oxford previously carried out the landmark Heart Protection Study which showed a third of all heart attacks and strokes could be avoided in people at risk of vascular disease by using statins to lower “bad” cholesterol or low density lipoproteins (LDL). Large-scale trials have shown that lowering LDL for four to five years cuts the risk of heart attacks and stroke by a quarter. But the risk among patients who already have vascular disease remains high even with the use of statins and there is limited scope for reducing LDL much more, so researchers are starting to look at ways of also increasing HDL. Dr. Jane Armitage who is leading the trial said: “The difficulty has been that there haven’t been good quality drugs that raise HDL very much. The trial will be in people at risk of future heart problems despite the fact that their LDL cholesterol has been lowered. If it’s shown to work, the epidemiology suggests it will be possible for people at lower risk of heart problems to benefit.” Professor Gilbert Thompson, a lipidology expert at Imperial College said treatments which raise HDL were the “next step” in cholesterol research. “It seems a perfectly reasonable approach but it won’t necessarily give you a straight answer about HDL because niacin also lowers triglyceride. But it will be a good trial. Dr. Anthony Wierzbicki, Chair of Heart UK Scientific Medical and Research Committee, said looking for ways of raising HDL in addition to lowering LDL was the next logical step. “There are a number of trials looking at this that are either under way or starting soon, all following the protocol of adding HDL-raising agents to baseline statin therapy in a variety of patient populations.” A group of drugs called CETP inhibitors have also been shown to increase levels of “good” cholesterol and are currently in clinical trials. Total number of words in 1 minute: _______