Stanford Study Finds Link Between Heartburn Drugs, Heart Attack Risk
Using drugs to reduce or eliminate heartburn could result in a significantly higher risk of experiencing a heart attack, according to a study of electronic health record data by Stanford University researchers, KQED's "State of Health" reports.
Background on Heartburn Drugs
The heartburn medications -- known as proton pump inhibitors, or PPIs -- are sold over-the-counter and by prescription, and more than 20 million U.S. residents use the drugs. Two popular brands are AstraZeneca's Nexium and Procter & Gamble's Prilosec (Aliferis, "State of Health," KQED, 6/10).
The drugs work by preventing the release of acid into the stomach (Bernstein, "To Your Health," Washington Post, 6/10).
PPIs generate about $13 billion annually in sales worldwide, according to "State of Health" ("State of Health," KQED, 6/10).
Details of Study
For the study, researchers designed algorithms to mine the de-identified EHR data of nearly three million patients (Harris, "Shots," NPR, 6/11).
Nigam Shah, one of the study authors, said, "We figured out a way to analyze the notes that doctors write about their patients during the course of care ... and created a data structure which we (could) then analyze for associations that may have clinical significance."
The study found that taking PPIs was associated with a 16% to 20% higher risk of heart attack.
The study excluded patients who also take the anti-platelet medication clopidogrel, which has been found to increase risk of heart attack among patients also taking PPIs ("State of Health," KQED, 6/10).
Researchers did not find an increased risk of heart attack with other heartburn medications, such as Pepcid, Tagamet or Zantac ("Shots," NPR, 6/11).
According to the researchers, the findings could suggest that PPIs alter nitric oxide levels.
Nick Leeper, a cardiologist and senior author of the study, said, "It's widely accepted that having reduced levels of nitric oxide is a bad thing and is associated with risks for cardiovascular events."
Leeper said the research cannot prove causation between the use of PPIs and increased heart attack risk, but that the "association looks to be fairly compelling." He added, "What we have seen in this study is that PPI usage is very clearly associated with increased risk of heart attack."
In addition, Leeper said the study shows that "post-approval surveillance" of drugs can be helpful, as pharmaceutical companies "simply can't identify every harm." He also said it shows the value of using EHR data for drug research.
Bob Wachter, chief of UC-San Francisco Medical Center's division of hospital medicine, said the study makes it "clear that the promise of computerization is real" in medical research ("State of Health," KQED, 6/10).This is part of the California Healthline Daily Edition, a summary of health policy coverage from major news organizations. Sign up for an email subscription.