New link between acid reflux medicines and dementia

Previously linked to a higher risk of stroke and heart attack, popular acid reflux medicines have now been connected to an increased likelihood of developing age-related dementia.

The medicines are a specific kind of treatment known as proton pump inhibitors (PPIs), which as the name suggests act on the proton pumps that produce acid released into the stomach. This prevents excess acid flowing into the esophagus and causing heartburn and other serious gastrointestinal issues, which can even lead to cancer.

They’re one of the most commonly used medicines across the globe, with an estimated 15 million Americans taking them annually. They’re both available with prescription and in over-the-counter form.

In the US, you’ll find Omeprazole (Prilosec, Prilosec OTC, Zegerid), Esomeprazole (Nexium, Nexium 24HR), Lansoprazole (Prevacid, Prevacid 24HR), Dexlansoprazole (Dexilant), Pantoprazole (Protonix), Rabeprazole (AcipHex) and Esomeprazole/ Naproxen (Vimovo).

“Proton pump inhibitors are a useful tool to help control acid reflux, however long-term use has been linked in previous studies to a higher risk of stroke, bone fractures and chronic kidney disease,” said study author Kamakshi Lakshminarayan, of the University of Minnesota School of Public Health in Minneapolis. “Still, some people take these drugs regularly, so we examined if they are linked to a higher risk of dementia. While we did not find a link with short-term use, we did find a higher risk of dementia associated with long-term use of these drugs.”

The American Academy of Neurology researchers looked at 5,712 people in the Atherosclerosis Risk in Communities (ARIC) Study, aged 45 to 64, who did not have dementia at the time of their first health assessment (1987-1989).

Nearly 1,500 participants, more than a quarter, took PPIs during the study time. After adjusting figures for age, sex, race and comorbidities such as high blood pressure, the researchers found that those using PPIs for 4.4 years or longer had a 33% higher risk of developing dementia than those who never took the drugs. Some 497 participants reported prolonged PPI use (more than four years, four months) and 58 developed dementia.

However, there was no elevated risk for anyone who had intermittent PPI use or took them for a period less than the statistical red flag of four years and four months.

Of course, this study does not probe causation, but provides a lot of new scope for studying long-term medicine usage and what other mechanisms might be triggered by proton pump inhibition.

“While there are various ways to treat acid reflux, such as taking antacids, maintaining a healthy weight, and avoiding late meals and certain foods, different approaches may not work for everyone,” said Lakshminarayan. “It is important that people taking these medications speak with their doctor before making any changes, to discuss the best treatment for them, and because stopping these drugs abruptly may result in worse symptoms.”

There are also PPI alternatives such as H2 blockers, which act by binding to the histamine type 2 receptors on the surface of gastric parietal cells, disrupting acid production and secretion.

However, the scientists urge caution with altering medications and note that the study has its limitations, such as accuracy in self-reporting, and confounding health links such as the potential elevated risk of dementia due to depleted B12 levels (B12 was not assessed in participants). And not all previous work on PPIs and cognition have offered conclusive negative results.

“More research is needed to confirm our findings and explore reasons for the possible link between long-term proton pump inhibitor use and a higher risk of dementia,” said Lakshminarayan.

The research was published in the journal Neurology.

Source: American Academy of Neurology.