MONDAY, May 7, 2007 (HealthDay News) -- In addition to their well-established role in preventing heart disease, cholesterol-lowering statins may also dramatically reduce the risk for lung cancer among men, a new study suggests.
U.S. researchers found that patients taking a statin for at least six months experienced a drop in lung cancer risk of 55 percent. Almost all the patients in the study were men.
"What these researchers have done is to examine a large collection of data that's already out there to show that the use of statins is a plausible preventive treatment for patients with lung cancer, or patients who are going to develop lung cancer," said Dr. Neil Schachter, medical director of the respiratory care department at Mount Sinai Medical Center in New York City.
Schachter, who is also a professor of pulmonary medicine, did not work on the study, which is published in the May issue of Chest.
"Whether statins are really useful in this kind of situation has not been firmly established as yet," stressed Schachter. "But there has been a lot of work to suggest that they might be. Particularly because chronic obstructive pulmonary disease -- which is the most common of lung diseases caused by cigarette smoking -- usually occurs with other diseases, so that most people who die of lung disease die of something else. And one of the major things they die of is heart disease. So, treating the heart disease with statins, perhaps, would not surprisingly be expected to prolong life."
Lung cancer remains the biggest cancer killer in the United States. According to the American Cancer Society, in 2007, almost 214,000 new cases of lung cancer will be diagnosed. More than 160,000 men and women will die of the disease this year, which in more than 80 percent of cases is linked to smoking. Approximately 60 percent of lung cancer patients do not live one year after diagnosis.
Millions of Americans already take statins -- commonly known by brand names such as Lipitor, Mevacor, Pravachol, and Zocor -- to diminish their risk for heart disease.
In recent years, many studies have explored a possible connection between statins and reduced cancer risk, based on the theory that statins may inhibit the onset and growth of malignancy at the molecular level. However, studies on skin, colorectal, and, more recently, lung cancer risk have so far proven inconclusive.
Exploring further, a team led by Dr. Vikas Khurana, of the department of medicine at Overton Brooks VA Medical Center in Shreveport, La., pored over six years of data amassed by the VA Health Care System (VAHCS). The information concerned almost 484,000 patients between the ages of 18 and 100 from eight southern states.
Almost 98 percent of the patients were men, all of who had sought treatment either at the VAHCS primary care clinic or hospital between 1998 and 2004.
About 1.5 percent of the patients had lung cancer, of whom nearly three-quarters were smokers. Just over a quarter of the cancer patients had been taking statins prior to their diagnosis.
Irrespective of race, body mass index, diabetes status, age, or smoking and drinking histories, statin use exceeding six months was linked to a significant lung cancer risk reduction of 55 percent, the researchers found.
This protective effect rose along with the length of time statins were used. Those patients who took a statin for four years or more had a 77 percent reduction in lung cancer risk, the team noted.
However, statin use of less than six months was associated with an increased risk for developing lung cancer.
But Khurana and his colleagues dismissed the notion that statin use actually caused this bump in risk. Instead, they attributed the finding to pre-existing conditions that went unnoticed or misstated in the early stages of study participation.
While encouraging, the new findings need to be replicated among a more diverse group of patients, including more women and non-veterans, the researchers said.
"We have very strong data based on actual patient chart review, not simply patient recall," noted Khurana, who is currently an associate professor of medicine at Temple University Hospital in Philadelphia. "But there have been conflicting reports about statins being protective or not, and we were surprised by the high percentage of protection we saw. So we will need to look at this some more to see if other factors correlated with stain use is related to the cancer protection we found."
Future studies should also consider statin dosage and type, as well as other contributing risk factors for cancer such as diet, genetic background, and the possibility of underlying lung disease, his team said.
"What we need to do with future research is get to the point where we can start patients on this medication specifically for cancer prevention," according to Khurana. "Because, right now, we still cannot say that people should take statins to protect against cancer. But we can say that if they have a cholesterol problem and they're taking statins already, they might be deriving additional benefits against cancer from the medications."
Dr. Walid G. Younis, a pulmonary fellow at the University of Oklahoma Medical Center in Oklahoma City, said he was a little surprised at the study findings.
"We did a statin study about one year ago that did not show any benefit in decreasing lung cancer incidence," he cautioned. "It was a much smaller study, but still it makes me wonder if these conclusions will hold true. Especially because the mechanism by which statins might reduce the risk of lung cancer is not very clear. But, certainly, it's absolutely worth continuing to look at the protective possibility of statins."
Schachter agreed that further research is needed.
"Does this study prove that statins are useful for the treatment of lung cancer?" he posited. "No. Will the FDA now approve statins as safe and effective for the treatment of lung cancer? No, not based on this study. It's not definitive. But this work is certainly interesting, and it will spark interest in more research."
For additional information on lung cancer, visit the American Cancer Society.