Acupressure against nausea and vomiting? The evidence is far from convincing

Acupuncture is not just one single form of therapy, there are dozens of variations of this theme. For instance, acupuncture-points can, according to proponents of this form of treatment, be stimulated in a number of ways: needles, heat (moxibustion), electrical current, laser-light, ultrasound or pressure. In the latter case, the therapy is called acupressure. This therapy is popular and often recommended as a form of self-treatment, for instance, to alleviate nausea and vomiting of all causes.

Chemotherapy-induced nausea/vomiting can normally be successfully treated with standard anti-emetic drugs. Some patients, however, may not respond satisfactorily and others prefer a drug-free option such as acupressure for which there has been encouraging evidence. A brand-new study sheds new light on this issue.

Its objective was to assess the effectiveness and cost-effectiveness of self-administered acupressure using wristbands compared with sham acupressure wristbands and standard care alone in the management of chemotherapy-induced nausea. Secondary objectives included assessment of the effectiveness and cost-effectiveness of the wristbands in relation to vomiting and quality of life and exploration of any age, gender and emetogenic risk effects. The trial was conducted in outpatient chemotherapy clinics in three regions in the UK involving 14 different cancer units/centres. Chemotherapy-naïve cancer patients were included receiving chemotherapy of low, moderate and high emetogenic risk. The intervention were acupressure wristbands pressing the P6 point (anterior surface of the forearm), sham-wrist bands providing no pressure on acupuncture-points or no wrist-bands at all; all three groups had standard care in addition. The main outcome measures were the Rhodes Index for Nausea/Vomiting, the Multinational Association of Supportive Care in Cancer (MASCC) Antiemesis Tool and the Functional Assessment of Cancer Therapy – General (FACT-G). At baseline participants also completed measures of anxiety/depression, nausea/vomiting expectation and expectations from using the wristbands.

In total, 500 patients were randomised (166 standard care, 166 sham acupressure + standard care, and 168 acupressure + standard care). Data were available for 361 participants for the primary outcome. The primary outcome analysis (nausea in cycle 1) revealed no differences between the three arms. Women responded more favourably to the use of sham acupressure wristbands than men. No significant differences were detected in relation to vomiting outcomes, anxiety and quality of life. Some transient adverse effects were reported, including tightness in the area of the wristbands, feeling uncomfortable when wearing them and minor swelling in the wristband area.There were no statistically significant cost differences associated with the use of real acupressure bands.

In total, 26 patients took part in qualitative interviews. The qualitative data suggested that participants perceived the wristbands (both real and sham) as effective and helpful in managing their nausea during chemotherapy.

The authors concluded that there were no statistically significant differences between the three arms in terms of nausea, vomiting and quality of life.

Intriguingly, this study was published in two different journals; and the second article reporting the identical data concluded that no clear recommendations can be made about the use of acupressure wristbands in the management of chemotherapy-related nausea and vomiting.

A further equally new study tested acupressure for post-operative nausea/vomiting. One hundred and thirty-four healthy, non-smoking women scheduled for breast surgery were randomised either to P6 stimulation or to sham control. Wristbands were applied and covered with a dressing before induction of anaesthesia. Follow-up was carried out three times within 24 h postoperative. Primary outcomes were postoperative nausea and/or vomiting.

One hundred and twelve patients completed the study. There were no statistically significant differences in the incidence of nausea or vomiting. Approximately, one third of the patients reported adverse-effects caused by the wristband, for example, redness, swelling and tenderness.

The authors of this trial concluded as follows: We did not find the Vital-Band effective in preventing either nausea or vomiting after operation in women undergoing breast surgery.

There has been quite a bit of previous research on acupressure. The most recent summary included 2 meta-analyses, 6 systematic reviews and 39 RCTs of acupressure for various conditions. Its authors stated that the strongest evidence was for pain (particularly dysmenorrhoea, lower back and labour), post-operative nausea and vomiting.

So, is acupressure effective in reducing nausea and vomiting or not? The evidence is contradictory to a degree that is baffling. If we look closer at the existing trials, we are likely to find that the more rigorous studies and those published by researchers who do not have an axe to grind tend to produce negative findings. I am therefore not convinced that acupressure has any effects beyond placebo.