ACCELEROMETER-ASSESSED DAILY PHYSICAL ACTIVITY AND SEDENTARY BEHAVIOUR IN ADOLESCENTS WITH JUVENILE IDIOPATHIC ARTHRITIS (JIA) - FIRST RESULTS FROM THE GERMAN ACTIMON STUDY

Background Although regular physical activity (PA) is known to have many health-related benefits for children and adolescents with chronic conditions, JIA has been associated with reduced physical activity (PA) and increased time spent sedentary [1]. Sedentary behaviour is an important consideration alongside PA when examining the contribution of both behaviours to the health of young patients. Because young people show more complex but less structured movement behaviour than adults, capturing their many spontaneous and impulsive movements is a great challenge for PA assessment. Objectives Since accurate, objective measures of PA related to potential factors promoting PA have been scarce, this study aimed i) to objectively assess moderate to vigorous PA (MVPA) as well as sedentary behaviour and ii) to identify facilitators for PA in patients with JIA. Methods Within the framework of the ActiMON study as part of the TARISMA research network, data were collected at several German paediatric rheumatology centres. Objectively assessed PA of adolescent patients with JIA was recorded exclusively during school months in the period June - December 2021 using the accelerometer ActiGraph wGT3X-BT laterally on the right hip. In accordance with the International Children’s Accelerometry Database criteria [2], ActiGraphs were worn on seven consecutive days during all waking hours, including at least 4 valid weekdays and 1 weekend day (wear time >8 hours) in the evaluation. Self-reported PA-related data were measured using a physical activity questionnaire (PAQ), while clinical parameters were used from the National Paediatric Rheumatologic Database (NPRD). Achievement of the WHO recommendation of at least 60 minutes MVPA per day and compliance with the national recommendation of no more than 120 minutes of daily screen time were determined among 12- to 18-year-olds. Results Data of 41 patients (mean age 14.6 ± 1.9 years, female 73%, patients’ disease duration 7.9 ± 4.6 years, polyarthritis 40%, cJADAS-10 2.3 ± 2.4) were available for evaluation. Almost 71% of participating patients met the WHO-recommended minimum level of MVPA, while the average daily step count achieved was 7804. Almost 80% of the patients rated their motor and coordination skills as being good. The most frequently mentioned reasons for doing sports (multiple answers possible) included feeling good (78%), giving energy (70%), pleasure (65%) and enjoyment (60%). Patients whose parents are active in sports and support their child in finding a suitable offer were more likely to fulfil the WHO recommendation than patients without family support. The average daily time spent sedentary was 10.5 ± 1.9 hours. About half of the patients reported spending more than 4 hours a day with screen-based media, especially video games. Conclusion These preliminary results suggest that while a large proportion of patients achieve the WHO recommended minimum level of PA, they exhibit very pronounced sedentary behaviour with increased screen use. In addition to controlled disease activity as a well-known prerequisite for achieving PA recommendations, these results also point to the importance of family support and emotional well-being. With ongoing recruitment, further potential facilitators and barriers to PA should be identified in more in-depth analyses. References [1]Gualano B et al. Physical activity for paediatric rheumatic diseases: standing up against old paradigms. Nat Rev Rheumatol 2017;13:368-379. [2]Sherar LB et al. International children’s accelerometry database (ICAD): design and methods. BMC Public Health 2011;11:485. Acknowledgements ActiMON is funded by the Federal Ministry of Education and Research (01EC1902F). Disclosure of Interests Florian Milatz: None declared, Ralf Trauzeddel: None declared, Tilmann Kallinich: None declared, Moritz Klaas: None declared, Hermann Girschick: None declared, Sandra Hansmann: None declared, Gerd Horneff: None declared, Daniel Windschall Speakers bureau: Pfizer, Novartis, Abbvie, Medac, Sobi, Canon , Johannes-Peter Haas: None declared, Nadja Baumeister: None declared, Martina Niewerth: None declared, Kirsten Minden Speakers bureau: Pfizer; Novartis