Effect of Electroacupuncture on Opioid-induced Constipation in Patients With Cancer

Approximately 70-80% of patients with advanced disease will be affected by moderate to severe pain. Opioid analgesics represented by morphine and oxycodone are the cornerstone of cancer-pain management, and recommended for use in the management of moderate to severe cancer pain according to WHO Cancer Pain Relief Guidelines. One view is that a trial of systemic opioid therapy should be administered to all cancer patients with pain of moderate or greater severity regardless of the pain mechanism. Although opioids analgesics do work well as relieving pain and improving quality of life via their action at opioid receptors in the central nervous system (CNS) and the peripheral nervous system, they also have powerful adverse effects. The overall occurrence of opioid-related adverse drug events has ranged from1.8% to 13.6%. Opioid-induced constipation (OIC), one of the most prevalent adverse events (AEs) in patients receiving opioid analgesics, defined as a change in baseline bowel habits or defecatory patterns following initiation, alteration, or increase in opioid therapy. The prevalence of OIC has been estimated to affect 41% of patients with chronic noncancer pain taking opioids and 94% of cancer patients taking opioids for pain. Unlike many other opioid-related AEs, OIC is persistent and rarely tolerated. OIC impacts pain control, patients' quality of life and may cause patients to reduce the dose or discontinue opioid use. Acupuncture, a traditional Chinese medicine, has been used to treat gastrointestinal disease including constipation for thousands of years. Two systematic reviews concluded that acupuncture can improve spontaneous bowel movements for functional constipation, and our recent study indicated that electroacupuncture(EA) could increase complete spontaneous bowel movements and is safe for chronic severe functional constipation. Acupuncture could improve gastrointestinal function via facilitating gastrointestinal motility. Currently, there is little det