Findings of a recent study suggest that statins may substantially cut the risk of developing cancer in heart-transplant patients. Results of the retrospective analysis were published online July 3, 2012 in the American Heart Association journal Circulation.
"We saw a large reduction in risk of cancer with statins in heart-transplant patients,” said Frank Ruschitzka, MD at University Hospital Zurich, Switzerland, in an interview following publication. “This is the first study to look at this issue, which is an important one, as transplant patients are at increased risk of developing cancer."
According to the National Institutes of Health, "Suppressing the immune system leaves patients at risk for cancers and malignancies. Malignancies are a major cause of late death in heart transplant patients." The most common post-heart transplant malignancies, says the NIH, are tumors of the skin and lips (especially in older, male, and fair-skinned patients) and malignancies in the lymph system, such as non-Hodgkin's lymphoma.
Dr. Ruschitzka and colleagues examined data from 255 patients who had a heart transplant between 1985 and 2007 and had survived the first year. Statins (mostly simvastatin and pravastatin) were taken by 151 patients. Patients were followed until 2010. The primary outcome measure was the occurrence of any malignancy. The secondary end point was overall survival.
A malignancy was diagnosed in 108 patients (42 percent) during follow up, the authors reported. The cumulative incidence of tumors eight years after transplantation was reduced in patients receiving a statin (34 percent vs. 13 percent, p < .003).
Statin use was also associated with improved cancer-free and overall survival (both p < .0001). A Cox-regression model analyzing the time to tumor formation with or without statin therapy, adjusted for age, male gender, type of cardiomyopathy, and immunosuppressive therapy demonstrates a superior survival in the statin group. Statins reduced the hazard of occurrence of any malignancy by 67 percent (HR 0.33, 95 percent, p <. 0001).
"Although it is not possible to adjust for all potential confounders due to the very long follow-up period, this registry suggests that statin use is associated with improved cancer-free and overall survival after cardiac transplantation," the authors concluded.
Dr. Ruschitzka said:
Our results suggest that this is another reason to make sure heart-transplant patients take a statin. They should already be taking one, as statins have been shown to reduce graft atherosclerosis and cut rejection rates, but now we think they reduce the risk of cancer in this population as well.
While newer immunosuppressive regimens have already improved the situation to some degree, the authors of the Circulation article note that the incidence of malignancy is still about 20 percent after 10 years of chronic immunosuppression, and the relative risk as compared with the general population may increase 100-fold for some cancers.
Heart-transplant patients are at particular risk of developing malignancies, noted Dr. Ruschitzka, with risk increased up to four-fold that of renal-transplant recipients.
"The evidence for these findings being attributable to statins is alluring," wrote Drs. Noel Clarke and Michael Brown of Christie Hospital in Manchester, UK, in an accompanying editorial. They described the cancer reduction reported in this study as "impressive":
For the moment, however, it may be safer to adopt a verdict of 'unproven', while recognizing the fact that in this study, as in many others, the statistical arrows relating to statins and their anticancer effect are pointing in a similar direction.
As one who takes a low dose of a statin daily to lower cholesterol, I hope those "statistical arrows" will eventually point to an anticancer effect for statins in the general population as well.
- Frölich GM, Rufibach K, Enseleit F, et al. Statins and the risk of cancer after heart transplantation. Circulation 2012; Jul 3. [Epub ahead of print]. Available at: http://circ.ahajournals.org/content/early/2012/06/28/CIRCULATIONAHA.111.081059.full.pdf+html.
- NHLBI, NIH. What Are the Risks of a Heart Transplant? http://www.nhlbi.nih.gov/health/health-topics/topics/ht/risks.html.
Jan 3 2012.
- Clarke NW and Brown MD. Should all patients receive statins to reduce cancer risk after heart transplantation? Circulation 2012; DOI: 10.1161/CIRCULATIONAHA.112.121343. Available at: http://circ.ahajournals.org/content/early/2012/06/28/CIRCULATIONAHA.112.121343.full.pdf+html.