Cannabis use may improve motility in patients undergoing esophageal manometry

Habitual use of cannabis may reduce weak swallows and lower the prevalence of ineffective esophageal motility in patients referred for esophageal manometry, suggests a study.

“In patients referred for dysphagia, chronic cannabis use is associated with increased integrated relaxation pressure and lower esophageal sphincter resting pressure, though not to levels above the normal range,” the investigators said.

This study identified patients who underwent high-resolution esophageal manometry (HREM) from 2009 to 2019 at four academic medical centres. Participants had a history of chronic cannabis use, a diagnosis of cannabis-related disorder, or a positive urine toxicology screen. Age- and gender-matched patients with no history of cannabis use served as controls.

The investigators then compared data on HREM metrics based on the Chicago classification V3 and the prevalence of esophageal motility disorders. Adjustments were made for the confounding effects of body mass index and medications on esophageal motility.

Chronic cannabis use showed an independent, negative association with weak swallows (β, ‒8.02; p=0.0109) but not with failed swallows (p=0.6890).

Chronic cannabis users also had a significantly lower prevalence of ineffective esophageal motility than nonusers (odds ratio [OR], 0.44, 95 percent confidence interval, 0.19‒0.93; p=0.0384). The prevalence of other esophageal motility disorders did not differ significantly between the two groups.

In patients with dysphagia as their primary indication for HREM, chronic cannabis use resulted in greater median integrated relaxation pressure (β, 6.638; p=0.0153) and higher mean lower esophageal sphincter resting pressure (β, 10.38; p=0.0084).

“Tetrahydrocannabinol, the main psychoactive compound in cannabis, binds with high affinity to the cannabinoid 1 receptor,” the investigators said. “Small randomized controlled studies using conventional manometry have shown that the cannabinoid 1 receptor can modulate esophageal function, namely transient lower esophageal sphincter relaxation frequency and lower esophageal sphincter tone.”