Advancements in Refractory Gastroparesis Treatment

Gastroparesis is a rare gastrointestinal disorder that affects about 4% of the patient population.

Gastroparesis is a rare gastrointestinal (GI) disorder that affects about 4% of the patient population. It generally affects patients with diabetes and those who undergo surgery, but in many cases, it’s idiopathic.

Idiopathic gastroparesis is the most common cause of gastroparesis, with an incidence of half of patients presenting with delayed gastric emptying.1,2 This disorder affects women (typically young or middle-aged) more than men, partly because women have a slower gastric emptying time.3

The vagus nerve communicates with the GI tract, and a series of events occur to regulate gastric emptying. Although the mechanism of gastroparesis isn’t fully understood yet, it involves abnormal functioning of the sympathetic and parasympathetic nervous system, as well as interstitial cells.

Studies have uncovered defects in some of the cells that contribute to this process, in addition to an increased concentration of inflammatory cells.3 This series of events causes symptoms like nausea, vomiting, diarrhea, bloating, pain, and decreased appetite. Additionally, abdominal pain is generally seen in patients with idiopathic gastroparesis.1-3

This disabling disease is often managed by a combination of dietary changes, correction of electrolyte abnormalities, prokinetic medications, antiemetic therapy, and psychotropic agents.3 Disease management is tricky and patients have varied response rates. As with all diseases, laboratory tests and imaging will help rule out a differential diagnosis. In patients with idiopathic gastroparesis, a gastroduodenal manometry can help discern whether it’s due to a myopathic or neuropathic process.1

A potential treatment option for idiopathic gastroparesis was presented at this year’s Digestive Disease Week. Known as the gastric peroral endoscopic myotomy (G-POEM), the treatment uses the principles of mucosal entry, tunneling, myotomy, and closure of mucosal entry, which is a similar to the POEM procedure for the treatment of achalasia. G-POEM has been explored in 2 studies and is targeted for patients with gastroparesis refractory to conventional medical treatment.2

The first study involved 30 patients with refractory gastroparesis. The mean duration of the G-POEM procedure was 72 minutes, with a mean hospital stay of 3.3 days. Mean follow-up occurred at 5.5 months and showed that 26 patients (86%) achieved a clinical response, which was defined as improvement in gastroparesis symptoms without re-hospitalization. Four patients (12%) didn’t achieve a clinically significant response, and 2 (6.7%) experienced adverse events, none of which were serious.2

The positive results of this study has propagated the start of a multicenter prospective trial in the United States, South America, and Asia with 50 patients.2

The second study involved 9 patients who were refractory to medical treatment, 2 of whom were refractory to gastric electrical stimulation. The mean duration of the G-POEM procedure was 48 minutes, and all patients were discharged from the hospital in 5 days. Notably, 85% of the patients had a significant clinical improvement at 1 month post-procedure, while only 1 patient experienced disease recurrence.2

Although these results are case series, they look like they can be applied to a larger population. With a rare digestive disease such as gastroparesis, any advancement in treatment is considered a leap in the care of these patients. For many patients, this chronic disorder is debilitating and affects every aspect of life. Therefore, a potential for symptomatic cure and relief of delayed gastric emptying can be life-altering.

References

1. Camilleri M. Gastroparesis: etiology, clinical manifestations, and diagnosis. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. Accessed June 19, 2016.

2. Helwick C. Gastric endoscopic myotomy showing promise for gastroparesis. Medscape. medscape.com/viewarticle/863847. Published May 25, 2016. Accessed June 19, 2016.

3. Parkman HP. Idiopathic gastroparesis. Gastroenterol Clin North Am. 2015 March;44(1):59-68.