Background Ankylosing Spondylitis (AS) is a systemic inflammatory disease that affects mainly the spine and compromises globally the physical capacity of the patients. Despite new advances in pharmacological therapy, physiotherapy and exercise remain essential in the treatment of AS. However, the literature lacks studies showing which types of exercises are more effective in patients with AS.
Objectives The purpose of this study is to evaluate the effects of aerobic exercise in functional capacity, disease activity, mobility and aerobic capacity of patients with AS.
Methods Sixty-eight patients with a diagnosis of AS, according to New York modified criteria and with stable drug treatment, were included. The patients were randomly allocated in two groups. The intervention group (IG) underwent fifty minutes of walking in the individual anaerobic threshold associated with stretching exercises three times a week for twelve weeks. The control group (CG) performed stretching exercises three times a week for 12 weeks. The outcome measurements were: functional capacity measured using BASFI (The Bath Ankylosing Spondylitis Functional Index) and HAQ-S (Health Assessment Questionnaire for spondyloarthritis); mobility measured using BASMI (The Bath Ankylosing Spondylitis Metrologyl Índex); disease activity by BASDAI (The Bath Ankylosing Spondylitis Disease Activity Index) and dosage of CRP (C-Reactive Protein). Aerobic capacity was evaluated using an incremental cardiopulmonary exercise testing protocol by treadmill. Additionally, the 6-minute walking test (6MWT) was applied. The evaluations were done by a blinded assessor immediately before the randomization, six weeks, and twelve weeks after the beginning of the exercise programs.
Results Sixty-four patients (32 in IG and 32 in CG) completed the study. Two patients from IG e two patients from CG withdrew because of difficulties in getting permission from work. At baseline, the groups were homogeneous regarding all clinical and demographic characteristics. There was significant improvement in functional capacity (BASFI and HAQ-S) and disease activity (BASDAI) in both groups (p<0.05), but there was no difference between groups. There were no significant differences in BASMI scores and CRP levels in both groups. The IG showed significant improvement in 6MWT compared to the control group (p<0.004). There was significant increase in VO2 peak and anaerobic threshold (AT) in IG after treatment. In CG, VO2 peak and AT did not change after 12 weeks. However, there was no difference between groups regarding aerobic capacity.
Conclusions Aerobic training and stretching exercises had beneficial effects on functional capacity and disease activity. Aerobic training, in addition to stretching exercises, increased walking distance and cardiopulmonary capacity in patients with AS.
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Disclosure of Interest F. Jennings: None Declared, M. Cardoso: None Declared, V. Cruz: None Declared, H. Oliveira: None Declared, J. Natour Grant/Research support from: Fundacao de Amparo a Pesquisa do Estado de Sao Paulo- FAPESP