Shreveport, LA - Observational data from a retrospective case-control study suggests that statins might protect against the development of lung cancer, with investigators reporting that statin use for more than six months was associated with a 55% reduction in the risk of lung cancer [1]. This chemoprotective effect was observed across different ages and racial groups and was irrespective of smoking.

While stressing that results should be interpreted cautiously, lead investigator Dr Vikas Khurana (Overton Brooks Veteran Affairs Medical Center, Shreveport, LA) and colleagues write that "due to the high prevalence of statin use and grave prognosis of lung cancer, even a modest risk reduction means a considerable effect on public health."

Publishing their findings in the May 2007 issue of Chest, the authors point out that previous studies have shown beneficial effects of statins on the incidence of certain cancers, including two 2005 studies that looked specifically at the risk of colorectal and prostate cancer. Not all the studies have been positive, however, as this protective benefit did not hold up in a recent meta-analysis, a study previously reported by heartwire. Published in the Journal of Clinical Oncology in 2006, the meta-analysis showed no decrease in the risk of cancer with statin use, and investigators concluded that the drugs do not appear to offer a protective effect. Other studies revealed no association between statin use and cancer risk.

Still, the possibility of an anticancer effect with statins has yet to go away, and with the conflicting data in mind, Khurana and colleagues sought to determine whether statins had a protective effect against lung cancer in the large US Veteran Affairs (VA) Health Care System, prospectively obtaining data on nearly half a million patients from eight states in the south-central US. Lung cancer and the use of statins prior to the diagnosis of lung cancer were the variables of interest, and multivariate regression analysis was performed to adjust for age, sex, body-mass index, smoking, diabetes, and race.

Statin use greater than six months was associated with a significant 55% reduction in the risk of lung cancer. The protective effects of statin therapy increased with statin duration, and although there was an increased risk of lung cancer associated with those who were on the drugs for less than six months, investigators do not believe statins caused this increase. More likely, write Khurana and colleagues, this group represents a skewed population due to recording of data at the time of entry of the patient into the database and might represent an old diagnosis at the time of entry into the VA Health Care System.

Although the analysis was adjusted for various risk factors, investigators did not adjust for other potential risks, including exposure to asbestos, halo ethers, hydrocarbons, nickel, arsenic, passive smoke, and radon, factors that are all implicated in the development of lung cancer. Also, dose, duration, and type of statin were not factored into the analysis, the authors write.