There are only a few studies looking at the analgesic effect of cold chamber exposures in patients suffering from fibromyalgia. However, in addition to the pain symptoms, patients with this syndrome also frequently suffer from an increased sensitivity to cold. Thus, the effect of cold chamber exposures (-67°C, 1-3 min) on the sensitivity to pain, thermal comfort and actual pain intensity was examined in 17 female patients with fibromyalgia (ACR criteria) and compared with a control group without applications.
The measured parameters were pressure, heat and cold pain thresholds (pressure algometry, Peltier thermode), thermal comfort (local thermal cutaneous stimulation applied by a Peltier thermode; systematically varied stimulation sequence) as well as the actual pain intensity and feeling of general well-being (visual analogue scales, VAS). The thermal pain thresholds were determined on the inner surface of the forearm, and the sensitivity to pressure pain at the styloideus radii. The thermal comfort measurements were carried out at the forehead. After cold chamber exposures, cold and pressure pain thresholds were significantly or very significantly increased while no shifts of the threshold were evidenced for heat pain. In the range of the applied thermode temperatures of 17.5 – 27.5 °C the subjective temperature sensation curve was significantly increased after cold chamber exposure as compared to initial values and control period.
The mean thermal tolerance range calculated from the intersection points of comfort curve and temperatures applied showed a statistically significant increase. Such an improvement of the thermal tolerance could not be evidenced for the control group. The mean values of the actual pain scores (VAS) were also significantly reduced after cold chamber exposures, and the overall-being improved. It is concluded that cold chamber exposures have an analgesic effect in patients suffering from fibromyalgia and that in addition the thermal tolerance is increased.
Now, further studies have to be carried out to determine if repeated cold chamber applications yield in stable adaptive improvements of pain sensitivity and thermal discomfort.