Research has shown that by themselves, the diabetes drug metformin and cholesterol–lowering drugs known as statins are associated with reduced cancer mortality, but little is known about the effect on pancreatic cancer mortality when these drugs are taken together. Investigators at Rutgers Cancer Institute of New Jersey and other collaborators examined Surveillance, Epidemiology, and End Results (SEER) Medicare data to further explore this approach and found that exposure to statins for these patients was significantly associated with reduced overall mortality. Results of the work were presented as part of a poster session at the American Association for Cancer Research Annual Meeting.

Investigators analyzed SEER data from 12,572 elderly patients (median age 76 years) with primary pancreatic adenocarcinoma who were diagnosed between 2008 and 2012. Information on metformin and statin use was taken from Medicare Part D data. Of the participants analyzed, 91.7 percent died before the study ended with a median follow–up of 3.8 months.

Statin use was found to be significantly associated with an improved overall survival, and it was more pronounced in those patients who began to use statins after they were diagnosed. Metformin use was not significantly associated with overall survival neither in those who were taking the drug before they were diagnosed nor after. Additionally, no superior benefit was observed for participants who used both drugs at the same time, say the authors, who add that further prospective validation is needed to confirm these findings.

“To the best of our knowledge, this is the largest U.S. population–based study to examine the differential and joint effects of metformin and statins on survival among pancreatic cancer patients. We found that exposure to statins, rather than metformin, is associated with an improved overall survival of pancreatic cancer patients. Although more research is need to confirm our findings, our data add to the evidence of recent publications on potential anti–cancer effects of statins, and highlight that drug exposure should be treated as a time–dependent variable to avoid the time–related bias in pharmacoepidemiological studies,” notes Rutgers Cancer Institute of New Jersey population science researcher Xiang–Lin Tan, MD, PhD, who is the senior investigator of the work, an assistant professor of medicine at Rutgers Robert Wood Johnson Medical School, and an assistant professor of epidemiology at Rutgers School of Public Health.