Gastroparesis, With Constipation, Common In Parkinson’s Disease

DECEMBER 8, 2016

San Diego—Most patients with Parkinson’s disease experience gastroparesis, a “disturbing” figure that could help explain why many people with the neurologic condition have difficulty taking medication for the illness, researchers have found.

The study used capsule technology to measure motility in patients with Parkinson’s disease at Stanford University and the Parkinson’s Institute, in Sunnyvale, Calif.

“The disturbingly high prevalence and magnitude of gastroparesis seen in this cohort may contribute not only to symptoms—bloating, weight loss—but also to altered pharmacodynamics of Parkinson’s disease medications, resulting in poor drug efficacy,” said Andrew Su, MD, now a gastroenterology fellow at the University of California, Los Angeles, who presented the findings at the 2016 Digestive Disease Week (abstract Mo1594).

Chronic constipation is the single most common gastrointestinal symptom associated with Parkinson’s disease, reported in up to 80% to 90% of patients, Dr. Su said. At the same time, delayed gastric emptying has been shown to be correlated with unpredictability of motor fluctuations in Parkinson’s patients, according to Dr. Su.

The wireless motility capsule is a simple device that is swallowed in the outpatient setting. It is a validated test that can be used to quantify colonic transit time in chronic constipation, but it can also measure transit time in the stomach, small intestine and whole gut, Dr. Su said.

The researchers assessed the prevalence and severity of gastric, small intestinal and colonic transit delay in 26 Parkinson’s patients presenting with constipation and undergoing evaluation with the capsule at the university’s neurogastroenterology and motility center. All patients underwent clinical examination and were off laxatives but were maintained on their neurologic medications, according to the researchers.

Of the 26 studies, 16 (62%) revealed prolonged gastric emptying, three (11%) showed prolonged small bowel transit, 18 (69%) found prolonged colonic transit and 20 (77%) revealed prolonged whole gut transit.

In patients with abnormal gastric emptying times, the mean was 7.8 hours, compared with 2.9 hours in those with normal times and almost twice the upper limit of normal, Dr. Su reported. In patients with prolonged colonic transit, the mean was 81.5 hours, nearly 50 hours longer than patients with normal tests, the researchers found.

Small bowel transit appeared to be preserved in most patients with Parkinson’s disease. However, small intestinal bacterial overgrowth, determined by a lactulose breath test, was observed in 30% of these patients, the researchers reported.

Dr. Su and his colleagues are conducting a prospective study involving more patients, and they will correlate capsule test results with qualitative patient-reported GI and neurologic symptoms. Therapeutic implications of these delayed transit times also should be determined in future research, he said.

Often ‘Hidden in the Neurology Clinic’

Gastroenterologists should be familiar with the association between Parkinson’s and constipation, but many times these patients are “hidden” in the neurology clinic, said Richard McCallum, MD, professor and founding chair of the Department of Internal Medicine at Texas Tech University Health Sciences Center, in El Paso, and an expert in gastroparesis.

“When gastroenterologists see them, the condition can be severe,” Dr. McCallum said. “In fact, these can be some of the worst constipation challenges we see.” Levodopa, the drug commonly used to treat Parkinson’s disease, may slow the transit time, Dr. McCallum said. However, the disease itself also involves the colon and can create transit problems regardless of the medication, he explained.

Indeed, severe constipation can be “an early tip-off” to underlying, undiagnosed Parkinson’s, he said.

In terms of management, “you just have to give [linaclotide (Allergan/Ironwood)], MiraLax and Dulcolax,” he said. “You can get the colon back to normal, but remember there is more to the gut. A slowed stomach often accompanies this condition; l-dopa can cause nausea; and there can be other symptoms in the GI tract.”

—Caroline Helwick

http://www.gastroendonews.com/In-the-News/Article/11-16/Gastroparesis-With-Constipation-Common-In-Parkinson-s-Disease/38523