title: Physical Activity in Ankylosing Spondylitis: evaluation and analysis of an eHealth tool.
abstract: Ankylosing spondylitis (AS) is a chronic inflammatory condition characterised by spinal arthritis and exercise is often recommended to reduce the symptoms and improve mobility. However, very little evidence exists for the value of exercise in AS.
  
  
  
  Firstly, this pilot study aimed to evaluate an eHealth tool, the AS Observer, specifically designed to monitor symptoms, quality of life and physical activity in AS, in terms of patient experience and suitability in generating data for epidemiological studies. Secondly, it also investigated the collected data to determine if physical activity benefited individuals with AS.
  
  
  
  The AS Observer was designed to enable weekly monitoring of AS symptoms and exercise using a web based platform. Participants with AS (n = 223) were recruited to use the AS observer. They provided baseline data and completed online weekly data entry for 12 weeks (e.g. Bath Ankylosing Spondylitis Activity Index (BASDAI), howRu, International Physical Activity Questionnaire (IPAQ)). Panel data analysis with fixed effects models investigated associations between variables. Activity type data and exit questionnaires were subjected to qualitative thematic analysis.
  
  
  
  In general, the AS Observer was well received and considered useful by participants, with 66% providing a positive response. The collected data suggested that IPAQ is inversely associated with total BASDAI, stiffness, tenderness and pain, but not fatigue. Stratified analysis demonstrated differential associations between BASDAI, IPAQ and howRU based on sex, HLA-B27 status and disease duration. Approximately half of the participants frequently did therapy and three-quarters undertook at least some vigorous activity ranging from formal exercise to recreation and (house) work. Despite some technical challenges, tool evaluation suggested that the AS Observer was a useful self-monitoring tool for participants.
  
  
  
  This pilot study demonstrated that increased exercise intensity and duration were associated with an improved BASDAI symptom score in a cohort of participants with AS. Furthermore, it provided further evidence of the value of using eHealth tools for clinical purposes and data collection for research, inclusive of the development of treatment pathways and disease management strategies.
authors.affiliation: University of Exeter Medical School, University of Exeter. j.tyrrell@exeter.ac.uk.
authors.forename: Jess Shelagh
authors.initials: JS
authors.lastname: Tyrrell
authors.affiliation: University of Exeter Medical School, University of Exeter. c.h.redshaw@exeter.ac.uk.
authors.forename: Clare Helen
authors.initials: CH
authors.lastname: Redshaw
mesh_terms: D004185:Disability Evaluation; D015444:Exercise; D006801:Humans; D026741:Physical Therapy Modalities; D010865:Pilot Projects; D011788:Quality of Life; D012720:Severity of Illness Index; D013167:Spondylitis, Ankylosing / Q000175:diagnosis* / Q000503:physiopathology* / Q000628:therapy; D011795:Surveys and Questionnaires; D017216:Telemedicine
keywords: Ankylosing spondylitis; e-health; physical activity