Researchers at Athens Medical School in Greece recently revealed that the drug buspirone offers clinical benefits to systemic sclerosis patients with esophageal dysfunction. The study was recently published in the United European Gastroenterology Journal and is entitled “Beneficial effect of the 5-HT1A receptor agonist buspirone on esophageal dysfunction associated with systemic sclerosis: A pilot study.”
Systemic sclerosis is a rare, chronic autoimmune disease in which the body’s own immune system attacks healthy tissues resulting in a hardening and tightening of the skin and connective tissues due to excessive collagen deposition. The disease usually affects the skin, but it can also affect internal organs such as the lungs, heart, blood vessels, kidneys and the digestive tract. The esophagus is the most commonly affected organ in the digestive tract of up to 90% of the systemic sclerosis patients, with individuals experiencing symptoms of gastroesophageal reflux disease (GERD) and esophageal motor dysfunction. Around 80% of the patients also experience symptoms of heartburn (burning sensation in the chest) and dysphagia (difficulty in swallowing). However, systemic sclerosis patients with esophageal disease may experience no symptoms, and when they do, the symptoms do not always correlate with the extent of esophageal disease.
Esophageal disease is usually managed with domperidone, a dopamine antagonist drug able to improve GERD and increase peristalsis, facilitating the transit of food through the digestive tract. Domperidone efficacy is, however, questionable. A possible alternative drug is the 5-HT1A receptor agonist buspirone, which has been found to enhance esophageal peristalsis and lower esophageal sphincter (LES) function in healthy volunteers. The 5-HT1A receptor binds to the endogenous neurotransmitter serotonin (5-HT), one of the putative neurotransmitters involved in esophageal motor function.
In the study, researchers investigated whether buspirone could have a beneficial effect on esophageal motor dysfunction in symptomatic systemic sclerosis patients. The team analyzed 20 systemic sclerosis patients with esophageal symptoms. All patients were submitted to high-resolution manometry (method to assess esophagus function) before and 30 minutes after administration of oral buspirone (10 mg). As a control group, ten systemic sclerosis patients received domperidone (10 mg) treatment.
Researchers found that in the cohort analyzed, 63% of the patients had esophageal dysfunction and 67% a lower LES. The resting pressure of LES was found to increase after buspirone treatment but not after domperidone. In addition, a trend for increased amplitude of contractions in the esophagus was also found upon buspirone treatment.
The research team concluded that buspirone was superior to domperidone in increasing LES pressure and, consequently, the esophageal function in systemic sclerosis patients. The authors suggest that future studies should assess whether buspirone has long-term therapeutic value for esophageal disease in systemic sclerosis patients.