Acupuncture relieves dry mouth caused by radiotherapy for head and neck cancers
Acupuncture can relieve the symptoms of dry mouth in patients undergoing radiotherapy, according to the largest trial yet to investigate this effect. Radiotherapy for head and neck cancer often produces this unpleasant and distressing side effect because patients' salivary glands are damaged by the radiation.
Approximately half a million people develop head and neck cancer each year, and few effective treatments currently exist for dry mouth, or xerostomia, which is a common side effect of radiotherapy. Five years after radiotherapy, as many as 41% of patients may still have dry mouth. Xerostomia affects patients' quality of life because it interferes with taste, chewing, speaking, and sleeping.
This study, involving seven cancer centers in the United Kingdom, recruited 145 patients with radiation-induced xerostomia. The patients were randomized to receive group acupuncture sessions for 20 minutes every week for 8 weeks, or to receive two oral care educational sessions for 1 hour, 1 month apart. Four weeks after the end of these two types of care, the patients were switched to the other treatment.
Symptoms of xerostomia were measured objectively with Schirmer strips, which are paper strips that measure the amount of saliva in the mouth. A quality of life (QOL) questionnaire measured the patients' subjective reporting of how their mouths felt through questions about individual symptoms such as sticky saliva, dry lips, needing to sip water to relieve a dry mouth, needing to sip water to swallow food, and waking at night to sip water.
Although the researchers found there were no significant changes in saliva production, patients who had received 8 weeks of acupuncture were twice as likely to report improved dry mouth as patients who were receiving oral care. Individual symptoms also significantly improved for the group receiving acupuncture.
The researchers stated that the subjective reporting of improvements in xerostomia was of more significance than the lack of changes in the objective test with the Schirmer strips. Richard Simcock, MRCP, FRCR, clinical oncologist at the Sussex Cancer Centre and an author of the study, explained, “There was no clear relationship between a patient indicating they had a very dry mouth and the measurement of saliva on the Schirmer strips. By definition these patients with chronic xerostomia produced little or no saliva, making objective measurements really difficult."
The researchers did not feel the improvements in xerostomia were due to a placebo effect. Dr. Valerie Jenkins, of University of Sussex, who supervised the research, explained, “The profound impact that xerostomia exerts on functions such as eating, talking and sleeping, which were relieved by the acupuncture means that if it is entirely a placebo effect than this is a pretty powerful placebo. In addition, the results showed that patients were less likely to wake at night to sip water after treatment – this effect seems difficult to ascribe solely to placebo."
Dr. Simcock stated, "This is a very neglected group of patients suffering from a most unpleasant side-effect of treatment for which all other ameliorative interventions have failed to address adequately. The acupuncture intervention has been designed in a way that allows it to be delivered simply and cheaply in normal hospital surroundings and yet still produces a significant benefit for patients with a chronic symptom."This study was reported in the Annals of Oncology (2012; doi:10.1093/annonc/mds515).