New Study Provides Insights into the Mystery of Restless Legs Syndrome

Researchers find link between Restless Legs Syndrome and the use of certain prescription antacid medications

RESEARCH TRIANGLE PARK, N.C. — A new observational study by the nonprofit research institute RTI International found that individuals have a significantly higher likelihood of developing restless legs syndrome (RLS) when consuming medications commonly used to reduce acid reflux.

RLS — a sleep disorder that affects up to 15% of adults in the United States — causes discomfort and pain in the legs, particularly at night, and triggers a constant urge to move the legs that makes falling asleep and staying asleep difficult. It also can lead to other serious health problems, including depression.

“RLS is difficult to diagnose and treat but our study provides new insights that could help provide relief to the many afflicted with this common disorder,” said Eric J. Earley, Ph.D., a statistical geneticist at RTI and lead author of the study. “Specifically, these findings suggest the need to re-evaluate the use of commonly used antacid medications in populations at particular risk for RLS.”

The study focused on two types of potent antacid medications that directly inhibit stomach acid secretion — proton pump inhibitors (PPI) and histamine type 2 receptor antagonists (H2A). The researchers explored the use of these PPI and H2A medications and the prevalence of RLS among two different populations of blood donors in the United States and Denmark and found that those who reported regularly or occasionally using two or more different gastric acid reducing drugs were about twice as likely to have RLS compared with those who took none.

While past studies have found that blood iron deficiency may play a key role in the development of RLS, this study did not find that. Instead, the study suggests that there likely are other mechanisms at play that determine how acid-reducing medications PPI and H2A are linked to RLS. Future studies will need to untangle the causality of this association applying longitudinal studies tracking exposure and RLS emergence over time.

The study, published in the journal SLEEP, was funded in part by the National Heart, Lung, and Blood Institute (NHLBI).