— A win in sham-controlled Chinese trial
by Diana Swift, Contributing Writer May 12, 2020

In patients with postprandial distress syndrome (PDS), acupuncture was safe and effective for symptom relief and even elimination, a randomized sham-controlled trial from China indicated.

A month-long course of acupuncture increased self-reported relief and improvement of primary symptoms, with effects persisting through 12 weeks of post-treatment follow-up and no symptom relapse or rebound, according to Cun-Zhi Liu, MD, PhD, of Beijing University of Chinese Medicine, and colleagues writing in Annals of Internal Medicine.

In addition, patients in the acupuncture group also reported improvements in dyspepsia symptoms and quality of life.

Although 18% of participants dropped out before study’s end, the estimated response rate at week 4 was 83% in the acupuncture group versus 51.6% in the sham group (difference 31.4 percentage points, 95% CI 20.3-42.5, P<0.001). The estimated elimination rate of cardinal symptoms targeted by the study was 27.8% in the acupuncture group and 17.3% in the sham group (difference 10.5 points, 95% CI 0.08-20.9, P=0.034).

These rates are higher than those reported for active pharmacologic therapy in irritable bowel syndrome, another functional gastrointestinal disorder. “[I]n the absence of a regulatory guideline on the magnitude of active drug response rate over placebo that can be considered clinically relevant, an expert group suggested that 10% to 15% improvement over placebo would constitute a clinically meaningful outcome,” Liu and colleagues wrote.

“If patients get proper treatment, they can feel improvement within two to four weeks,” coauthor Jing-Wen Yang, MD, PhD, also of Beijing University of Chinese Medicine, told MedPage Today. “This study has proved the effect of acupuncture on PDS with sufficient power. We are planning to research on the long-term effect of acupuncture that incorporates objective outcomes and daily measurement of symptoms.”

The authors noted that acupuncture for refractory PDS has been previously examined in only one adequately powered, placebo-controlled study.

PDS involves meal-related symptoms such as fullness, early satiation, bloating, and epigastric pain syndrome, as well as complaints such as epigastric pain or burning unrelated to meals, the group explained. Functional digestive disorders have been associated with autoimmune and atopic disease and with psychological comorbidities such as anxiety.

Nicholas J. Talley, MD, PhD, MMedSci, of the University of Newcastle in Australia, told MedPage Today the study appeared very well conducted. “Most impressive in terms of outcomes was applying a co-primary endpoint of symptom resolution, elimination, at 4 weeks which was met, and showing the benefit of acupuncture persisted after ceasing therapy, suggesting acupuncture might change the natural history of the disorder,” said Talley, who was not involved in the research.

Emerging data have suggested duodenal inflammation with increased eosinophils and eosinophil degranulation and duodenal microbiome changes may be important underlying mechanisms inducing PDS. “Whether acupuncture modulates these abnormalities via neural mechanisms is unknown but should be tested,” he said, adding that the findings indicated “no clear-cut mechanism for why acupuncture should work. Furthermore, the results might not be reproducible elsewhere owing to the need for expert delivery of acupuncture therapy.”

Study details

The researchers recruited 278 patients ages 18 to 65 from five sites during April 2017 to January 2019. Participants met Rome IV criteria for PDS and all had normal endoscopies within a year of enrollment. They were randomly assigned to 12 sessions (20 minutes three times a week) in an acupuncture arm (n=138) or a sham acupuncture arm (n=140) for 4 weeks. The mean ages in the two arms were 41.6 and 41.2 years, respectively, and women made up 72.5% and 62.1% of the two groups, respectively. About 22% in both arms tested positive for Helicobacter pylori.

Patients, outcome assessors, and statistical analysts were blinded to arm assignment but acupuncturists were not.

Patient questionnaires were used to record results, including a global assessment of the overall treatment effect and rating of eight symptoms (postprandial fullness, early satiation, upper abdominal bloating, epigastric pain, epigastric burning, nausea, vomiting, and belching) on a severity scale of 0 to 3 once a week during the treatment period and at weeks 8, 12, and 16 during follow-up. Patients also completed quality-of-life and psychological status questionnaires on depression and anxiety.

They were considered responders if they said their symptoms were “extremely improved” or “improved.” The elimination rate was defined as the proportion whose scores on the severity scale reached zero for all of the three cardinal symptoms (postprandial fullness, upper abdominal bloating, and early satiation) at week 4. Acupuncture therapy was deemed effective only if both these primary outcomes achieved significance. No serious adverse events occurred in either group.

According to the authors, the study’s limitations included its reliance on patient-reported rather than objective outcomes. Other limitations were the absence of daily measurements, the high dropout rate, and the inability to blind the acupuncturists. Moreover, the small number of patients with H. pylori precluded further subanalysis of this group. In addition, since the study was done in China, the results may not be applicable elsewhere.