Chronic use of some drugs for heartburn and gastroesophageal reflux (GERD) speeds up the aging of blood vessels, according to a published paper in Circulation Research, an American Heart Association journal. This accelerated aging in humans could lead to increased cardiovascular disease, vascular dementia and renal failure.
These findings by a Houston Methodist Research Institute team are a progression of the work that John Cooke, M.D., Ph.D., began more than five years ago, and support recent epidemiological and retrospective studies that observed associations between the long-term use of proton pump inhibitors (PPIs) and an increased risk of heart attack, renal failure and dementia.
PPIs like esomeprazole are widely used for the treatment of GERD. These medications are sold over-the-counter in some countries so medical supervision is not required. While these drugs are effective when taken as prescribed, they were not approved for long-term use and evidence suggests that up to 70 percent of PPI use may be inappropriate.
Cooke, the paper’s senior author, and team showed that chronic exposure to PPIs accelerated biological aging in human endothelial cells which line the inside of blood vessels. When healthy, human endothelial cells create a Teflon-like coating that prevents blood from sticking. When older and diseased, the endothelium becomes more like Velcro, with blood elements sticking to the vessel to form blockages.
“When we exposed human endothelial cells over a period of time to these PPIs, we observed accelerated aging of the cells,” Cooke said. “The PPIs also reduce acidity in lysosomes of the endothelial cell. The lysosomes are like cellular garbage disposals and need acid to work properly. We observed cellular garbage accumulating in the endothelial cells, which sped up the aging process.”
Cooke suspects that this may be the unifying mechanism that explains the increased risk of heart attack, renal failure and dementia observed in long-term PPI users.
“These drugs do not seem to adversely affect the heart and blood vessels when taken for a few weeks. However, we urgently need studies to assess the impact of long-term use of these drugs on vascular health in a broad patient population. We also need to consider if these drugs should be so accessible without medical supervision.”
Cooke’s earlier work identified at a molecular level that PPIs might cause long-term cardiovascular disease and increase a patient’s heart attack risk. That work led to a collaborative study with Stanford University colleagues (PLOS ONE, June 2015) to show that in two large populations of patients, adults who used PPIs were between 16 to 21 percent more likely to experience a heart attack than people who didn't use the commonly prescribed antacid drugs.
Cooke, who holds the Joseph C. “Rusty” Walter and Carole Walter Looke Presidential Distinguished Chair in Cardiovascular Disease Research, said while PPIs were shown to affect vascular aging, H2 blockers like ranitidine did not adversely affect the endothelium.
Source Newsroom: Houston Methodist
Circulation Research, May 2016
"Proton pump inhibitors accelerate endothelial senescence," by Cooke et al, Circulation Research (Online May 10, 2016)