INTERVAL HYPOXIC-HYPEROXIC TRAINING in REHABILITATION of PATIENTS with OSTEOARTHRITIS and POST-COVID SYNDROME

ABSTRACT

Background: Intermittent hypoxia conditioning reduces the levels of infam-matory parameters and cytokines (C-reactive protein, TNF-α, IL-4, IL-6, IL-8), increases the tolerance to acute hypoxia, the functional capacity and improves parameters of respiratory and cardiovascular systems [1-4]. Objectives: To evaluate the efficiency of the interval hypoxic-hyperoxic training (Reoxy therapy) in the rehabilitation of patients with osteoarthritis (OA) and post-COVID syndrome. Methods: 36 patients with OA (78% females, age of 43 to 68 years, generalized OA, OA of the knee or hip joints) where included in the randomized placebo-controlled study. Coronavirus infection COVID-19 were diagnosed from 12 to 26 weeks before the study. The main symptoms of post-COVID syndrome were dry cough, smell loss, breathlessness, weakness, fatigue, sleep disorders, cognitive symptoms, memory problems, anxiety, depression, headache, dizziness, joint and muscle pain. All patients were randomized into 3 groups. 13 study group patients received 10 Reoxy therapy procedures, 9 placebo group patients-10 placebo procedures of Reoxy therapy, 14 control group patients-only standard rehabilitation. The patients of all groups underwent 2-week standard rehabilitation program 10 procedures of electrostatic massage for muscles and periar-ticular tissues, 10 sessions of general magnetic therapy, 10 group sessions of physical exercises with elements of breathing exercises. All patients received NSAIDs and SYSADOA at standard dosages. Intra-articular corticosteroids was not used. The study group patients were breathing hypoxic (FiO2 13-15%) and hyperoxic (FiO2 up to 40%) gas mixture through the mask in the interval mode with biofeedback using device «ReOxy» (Ai Mediq S.A., Luxembourg). 10-min hypoxic test (FiO2 12-13%) was performed before the frst and fourth procedures. The duration of 1-4 procedures was 30 min, 5-10 procedures-40 min. The placebo procedures were performed using the mask with the atmospheric air hole. Joint pain and general health on 100-mm VAS, Lequesne and WOMAC indexes, Spielberger-Khanin anxiety test, Beck depression inventory and breath-lessness on Modifed Borg scale were evaluated at baseline and at 2 weeks. Results: After 2 weeks in the study group pain on VAS decreased by 49,6% (p<0,05), Lequesne index-by 39,3% (p<0,05), WOMAC-by 1,4 times (p<0,01), anxiety level on Spielberger-Khanin test-by 40,9% (p<0,05), depression level on Beck depression inventory-by 64,1% (p<0,01), general health on VAS improved by 69,3% (p<0,01). The level of breathlessness on Modifed Borg scale in the study group initially was 2,5±0,9 score (moderate-slight breathlessness). After rehabilitation in the study group the level of breathlessness decreased to 0,3±0,4 score (extremely slight-no breathlessness). In the study group there were statistically signifcant differences from the placebo group (p<0,05) and the control group (p<0,05) in all parameters. Conclusion: 2-week complex rehabilitation program, including interval hypox-ic-hyperoxic training (Reoxy therapy), reduces pain, breathlessness, depression and anxiety, improves functional status and general health in patients with OA and post-COVID syndrome.