A study led by researchers at Vanderbilt University Medical Center in Nashville, Tenn., assessed the feasibility of using electronic health records (EHRs) and automated informatics methods to validate a so-called drug repurposing signal. Specifically the researchers evaluated metformin, a diabetes drug, as having potential in the treatment of some types of cancer.
The study appears in the Journal of the American Medical Informatics Association.
The researchers scanned the records of approximately 32,000 cancer patients seen at Vanderbilt since the mid 1990s, looking at five-year survival with and without exposure to metformin. The team found that use of metformin as a therapy for type 2 diabetes was associated with: a 23 percent decrease in (all-cause) mortality compared with metformin-free, non-diabetic patients; a 22 percent decrease in mortality compared to other oral hypoglycemic medications; and a 39 percent decrease in mortality compared to diabetic patients receiving insulin but not metformin. The results were replicated with a cohort of approximately 79,000 cancer patients seen at the Mayo Clinic.
Site-specific cancers showing decreased mortality with metformin (in at least one of the two EHR cohorts) included breast, colorectal, lung and prostate.
“Our EHR allowed us to delve into details of treatment and response—cancer staging, control of cancer, the various timelines involved and cancer subtypes,” according to Joshua Denny, M.D., associate professor of biomedical informatics at Vanderbilt, in a prepared statement. The team drew on structured data from the clinical lab as well as natural language processing. “We’re now building on this study, pursuing opportunities for using our EHR to look at all drug exposures across a given disease—starting with cancer. We’re trying to find other signals that may look like metformin in terms of affecting patient outcomes,” Denny said.