RESUMEN
Abstract Introduction: Whole-body cryotherapy (WBC) has shown to be beneficial in the treatment of fibromyalgia (FM). There is cumulative evidence that cytokines play a crucial role in FM. It's unknown whether clinical effects of WBC can be demonstrated at the molecular level and how long the effects last. Methods: We compared effects of serial WBC (6 sessions (- 130 °C in 6 weeks) in FM patients and healthy controls (HC). Primary outcome was the change in pain level (visual analogue scale 0-100 mm) after 6 sessions. Secondary outcomes were a change in disease activity (revised Fibromyalgia Impact Questionnaire) and pain after 3 sessions and 3 months after discontinued therapy and in cytokine levels (interleukin (IL-)1, IL-6, tumor necrosis factor α (TNF-α) and IL-10). The patients' opinions on the satisfaction, effectiveness and significance of WBC were evaluated. Results: Twenty-three FM patients and 30 HC were enrolled. WBC resulted in a significant reduction in pain and disease activity after 3 and 6 sessions. No clinical benefit could be measured 3 months after discontinued treatment. Overall, probands were satisfied with WBC and considered WBC to be important and effective. FM patients had significantly different levels of IL-1, IL-6, TNF-α and IL-10 at each reading point compared to HC. Levels of IL-1, IL-6 and IL-10 were significantly altered over time in FM patients. Compared to HC FM patients showed a significantly different response of IL1, - 6 and - 10 to WBC. Conclusion: Serial WBC is a fast acting and effective treatment for FM. Proven effects of WBC may be explained by changes in cytokines.(AU)