Cryotherapy, or the use of extreme cold in short bursts to ease pain, is of benefit to people with fibromyalgia (FM) and may be an effective add-on treatment, a study in 60 patients suggests. The study, “The effect of cryotherapy on fibromyalgia: a randomised clinical trial carried out in a cryosauna cabin” were published in the journal Rheumatology International. Fibromyalgia (FM), a chronic disorder of unknown origin, is characterized by prevalent pain in muscle and bone (musculoskeletal) and areas of tenderness. It is accompanied by general fatigue, sleep problems, memory loss, joint stiffness, and trouble concentrating. Although medications, like pain-killers or sleeping aids, are often prescribed to help patients manage symptoms, non-pharmacological options are popular, and patients are known to try alternatives like acupuncture or hypnosis. Extreme cold, like ice packs, are often used for sports-related trauma, as cold is known to lessen inflammatory reactions. Researchers in Spain conducted a cross-over clinical trial (NCT03425903) to evaluate whether a procedure known as whole-body cryotherapy — applying extremely cold dry air in a controlled environment (a cabin or chamber) for short periods of time — would relieve pain in fibromyalgia patients. They enrolled 60 people, a mix of men and women 25 to 80 years old, who were diagnosed with the disease — according to the American College of Rheumatology (ACR) criteria — more than a year ago and who failed in whole or part to respond to other treatments. Patients were divided in two groups — 34 who started with whole-body cryotherapy (WBC) on alternate days for three weeks, and 26 who rested. Cryotherapy was given in 10 sessions lasting three minutes each, during which temperatures in the cabin fell to minus 196°C (about -385°F), "the evaporation point of liquid nitrogen," the study notes. A one-week washout period followed, then the groups switched treatment. Patients in both groups throughout the study continued using other medications, including painkillers. Effectiveness was measured by changes or differences in pain, assessed using the Visual Analogue Scale (VAS), and physical function, as evaluated by Fibromyalgia Impact Questionnaire (FIQ). Secondary trial goals were changes in disease severity, as measured by the Combined Index of Severity of Fibromyalgia (ICAF; includes both physical and emotional impact as well as coping abilities) and the 36-Item Short Form Survey (SF-36). At study start, the 34 patients in the first group had higher FIQ, ICAF, and SF-36 scores, which researchers linked to a “worse baseline clinical situation.” No differences in pain scores were observed between groups. After the washout period, pain levels in 33 treated patients were significant lower on the VAS scale compared to untreated patients, which the researchers attributed to the therapy. Positive changes were also noted in FIQ and ICAF scores. No significant changes were observed in SF-36 between the groups. One patient in the first group left the study after two treatments, citing tremor and muscle stiffness; none in the second group stopped. In total, side effects were reported by five patients, including heart palpitations and sleep problems, but all were mild and eased after the session concluded. “We have shown a significant effect of WBC on pain, impact of disease, and severity in a group of patients with FM and severe symptomatology and with mild undesired effects,” the researchers wrote, adding that this treatment may be a beneficial "adjuvant therapy" for fibromyalgia patients. "The mechanisms of action of cryotherapy are not well understood," they added. "Since there is no proven inflammatory component in fibromyalgia, it has been postulated that cryotherapy through a reduction of oxidants levels may reduce muscular damage and accelerate recovery after normal physical activity. As a consequence pain and fatigue may substantially improve."