Heartburn, also known as acid indigestion, is a burning sensation in the central chest or upper central abdomen. There are two types of drugs that work to reduce the production of acid in the stomach: histamine antagonists (H2 antagonists or H2 blockers) and proton pump inhibitors (PPIs). The recent concern relate to proton pump inhibitors.
Proton pump inhibitors are a group of drugs whose main action is a pronounced and long-lasting reduction of gastric acid production. Then drugs act act by irreversibly blocking the hydrogen/potassium adenosine triphosphatase enzyme system.
The earlier research about possible links to dementia, kidney and heart problems came from research performed by nephrologists at the Houston Methodist Research Institute, U.S. These findings inferred that proton pump inhibitors bring together cells that typically line the veins and arteries and cause them to stick together, which can trigger ill-health effects. This research was not fully supported by all scientists. This was because the research drew upon on a small number of selected studies for illustrative purposes and a more detailed systematic review would be required to establish the risk-to-benefits ratios of using heartburn drugs.
New research, based on a review of 250,000 medical records in Denmark, suggests there may be a link between popular heartburn drugs and a risk of stroke. The research has been conducted by the Danish Heart Foundation in Copenhagen. The review included medical records between 1997 and 2012, relating to gastric endoscopy procedures.
The review indicated that of the 250,000 patients some 9,500 of suffered from ischemic strokes. This type of stroke occurs when a blood clot blocks a blood vessel in the brain. Expressed in terms of probability, the data suggests that the risk of stroke was 21 percent higher in patients taking a proton pump inhibitor.
Furthermore, the analysis showed that the level of risk rises with an increased dose. Those taking the lowest drug doses (that is between 10 and 20 milligrams a day) did not have a higher risk; however, those taking relatively high doses (defined as more than 60 mg/day) had a 30 percent higher risk. Moreover, those taking an even higher dose (more than 80 mg/day) a 94 percent higher risk.
The researchers accounted for a number of possible influencing factors, including age, gender, high blood pressure, atrial fibrillation and use of medications that have been linked to poorer cardiovascular health. However, it should be noted that the research is ‘observational’, showing correlation and not causality. Further study will be needed to explore any causal factors.
The researchers further note that although proton pump inhibitors (which became commercially available diking the 1980s) help some patients there is a concern with some people taking the drugs for too long or for taking inappropriately high doses. The main reasons for this overuse of proton pump inhibitors are the prevention of gastro-duodenal ulcers in low-risk patients.
The research from Denmark has yet to be published in a peer reviewed journal. However, the data has been presented to a recent meeting of the American Heart Association (where the sessional paper was titled “Proton pump inhibitor use increases the associated risk of first-time ischemic stroke. A nationwide cohort study.”)
Essential Science
This article is part of Digital Journal’s regular Essential Science columns. Each week Tim Sandle explores a topical and important scientific issue. Last week looked at the farming of algae, as a potential super-food, was being developed through the use of sophisticated bio-reactors. The week before we showed how the remarkable meteorological formation the ice cloud — comes into existence.
