Effects of different local cryotherapies on systemic levels of TNF-α, IL-6, and clinical parameters in active rheumatoid arthritis

Cryotherapies are frequently used to supplement the rehabilitation of patients with rheumatoid arthritis (RA) owing to their analgesic and anti-inflammatory effects. Forty patients with active RA were recruited and received 10 days of comprehensive therapy with different local cryotherapies. None of the respondents were subjected to biological treatment. They were divided into two groups according to the therapy received: nitrogen vapour at −160 °C (group I) or cold airflow at −30 °C (group II). Levels of tumour necrosis factor α (TNF-α), interleukin 6 (IL-6), disease activity score (DAS28), and functional variables were used to assess the outcomes. After the therapy, both groups exhibited similar improvements. Significant reduction in TNF-α level (nitrogen: p < 0.01; cold air: p < 0.05) and no change in IL-6 were observed. DAS28, the clinical severity of pain, duration of morning stiffness, degree of self-reported fatigue, and health assessment questionnaire (HAQ) scores improved significantly. In addition, the active range of knee extension, time, and the number of steps in the 50-m walk test also clearly got better in both groups. The 10-day comprehensive therapies including different local cryotherapies for the patients with RA cause significant decrease in TNF-α systemic levels, meaningly improve DAS28, HAQ scores, and some functional parameters, but do not change IL-6 levels. However, there were no differences in the effectiveness of either cryotherapy.