Behaviour change intervention increases physical activity, spinal mobility and quality of life in adults with ankylosing spondylitis: a randomised trial

Questions: Does a 3-month behaviour change intervention targeting physical activity (PA) increase habitual physical activity in adults with ankylosing spondylitis (AS)? Does the intervention improve health-related physical fitness, AS-related features, and attitude to exercise? Are any gains maintained over a 3-month follow-up? Design: Parallel-group, randomised, controlled trial with concealed allocation, assessor blinding and intention-to-treat analysis. Participants: Forty adults with a diagnosis of AS, on stable medication, and without PA-limiting comorbidities. Intervention: Over a 3-month period, the experimental group engaged in individually-tailored, semi-structured consultations aiming to motivate and support individuals in participating in PA. The control group continued with usual care. Outcome measures: The primary outcome was PA measured by accelerometry over 1 week. Secondary outcomes included clinical questionnaires and measures of health-related physical fitness. Measures were taken at baseline, post-intervention, and after a 3-month follow-up period. Results: Baseline characteristics were similar across groups, except age and body composition. There were statistically significant, moderate-to-large time-by-group effects in health-enhancing PA (mixed-design ANOVA for overall effect F(2, 76) = 14.826, p < 0.001), spinal mobility (F(2, 76) = 5.691, p < 0.005) and quality of life (χ2(2) = 8.400, p < 0.015) favouring the intervention group; post-intervention improvements were sustained 3 months later. No significant effects were seen in other physical fitness outcomes or on clinical questionnaires. No adverse effects were reported during the study. Conclusion: Health-enhancing PA, spinal mobility and quality of life were significantly improved after the intervention, and improvements were maintained at 3-month follow-up. Trial registration: NCT02374502. [O'Dwyer T, Monaghan A, Moran J, O'Shea F, Wilson F (2016) Behaviour change intervention increases physical activity, spinal mobility and quality of life in adults with ankylosing spondylitis: a randomised trial. Journal of Physiotherapy XX: XX-XX]