Assessing the Impact of Familial Mediterranean Fever on Physical Activity in Children Using the Physical Activity Questionnaire for Children (PAQ-C): A Comparative Study with Healthy Controls

BACKGROUND: This study aimed to evaluate physical activity levels of children with Familial Mediterranean fever (FMF), and to compare these levels with age- and sex-matched healthy peers. A secondary aim was to investigate associations between physical activity, acute phase reactants (APRs), and disease activity scores. METHODS: This cross-sectional study enrolled FMF patients aged 9-14 years and matched healthy controls. Disease activity was assessed using Pras scores, Auto-Inflammatory Diseases Activity Index (AIDAI), and International Severity Scoring System for FMF (ISSF). Physical activity was evaluated weekly using the Physical Activity Questionnaire for Children (PAQ-C) over three months. Correlations of PAQ-C scores with APRs and disease activity parameters were analyzed at multiple time points, and repeated-measures analyses were performed. RESULTS: Overall, 140 participants were included (70 in control group and 70 in patient group). The study group had significantly lower PAQ-C scores than controls (2.75±0.71 vs. 3.37±0.54; p<0.001). Patients with exercise-related leg pain had significantly lower PAQ-C scores than those without pain (2.54±0.60 vs. 2.99±0.76; p=0.007). A significant negative correlation was found between age and PAQ-C scores in the study group (r=-0.377, p=0.001). PAQ-C scores were negatively correlated with ISSF scores (r=-0.278, p=0.020 and r=-0.288, p=0.016) and the AIDAI scores (r=-0.305, p=0.010 and r=-0.396, p<0.001) at first and the third months. CONCLUSION: This study demonstrates that children with FMF have reduced physical activity, particularly those with exercise-induced leg pain. The decline with age may reflect increased disease awareness, emphasizing the need for monitoring and promoting safe physical engagement in disease management.