Preventive effect of oral magnesium in postmastectomy pain: protocol for a randomised, double-blind, controlled clinical trial

Abstract

IntroductionBreast cancer affects 1 in 10 women worldwide, and mastectomy is a cause of chronic pain with neuropathic characteristics. N-methyl-D-aspartate receptor (NMDAR) antagonists such as ketamine, memantine, dextromethorphan or magnesium are used to treat refractory pain by blocking NMDAR. Oral memantine has been shown to prevent postmastectomy pain and cognitive impact and to maintain quality of life. Likewise, the present study is intended to assess the preventive effect of oral magnesium, administered ahead of mastectomy, on the development of neuropathic pain. As a physiological blocker of NMDAR, magnesium could be an interesting candidate to prevent postoperative pain and associated comorbidities, including cognitive and emotional disorders, multiple analgesic consumption and impaired quality of life.Methods and analysisA randomised double-blind controlled clinical trial (NCT03063931) will include 100 women with breast cancer undergoing mastectomy at the Oncology Hospital, Clermont-Ferrand, France. Magnesium (100 mg/day; n=50) or placebo (n=50) will be administered for 6 weeks, starting 2 weeks before surgery. Intensity of pain, cognitive and emotional function and quality of life will be assessed by questionnaires. The primary endpoint is pain intensity on a 0–10 numerical rating scale at 1 month postmastectomy. Data analysis will use mixed models; all tests will be two-tailed, with type-I error set at α=0.05.Ethics and disseminationThe study protocol and informed consent form were approved in December 2016 by the French Research Ethics Committee (South East VI Committee). Results will be communicated in various congresses and published in international publications.Trial registration numberNCT03063931.

Magnesium for Pain Treatment in 2021? State of the Art

“…The inhibition of NMDAR is one of the keys to blocking LTP. NMDAR antagonists like Mg may not only cure but also prevent the development of central sensitization [ 129 , 130 ], a very important aspect of 4P Medicine. However, available RCTs do not include a long follow-up period after surgery to identify if Mg could have an impact on the prevention of central sensitization.…”

Pharmacologic Management of Persistent Pain in Cancer Survivors

“…Magnesium is a nutrient with NMDA receptor antagonist activity and additional effects on muscle relaxation and anti-inflammatory mechanisms that has gained popularity due to its relative inexpensiveness and safety profile, despite inconclusive evidence on efficacy to date [ 124 , 125 ]. Studies are also underway for its wider application in managing cancer-related pain, including in the prevention of post-mastectomy syndrome [ 126 ].…”