Association of hand grip strength with disease activity, disability and quality of life in children and adolescents with Juvenile Idiopathic Arthritis

Background: Juvenile idiopathic arthritis (JIA) affects wrist and hand joints leading to decrease hand function and patients' daily living activities. The assessment of hand grip strength (HGS) in children and adolescents with JIA is of major importance, and the association of HGS with JIA disease activity, disability and quality of life has not been explored. The primary objective of this study was to evaluate hand grip strength (HGS) in children and adolescents with Juvenile Idiopathic Arthritis (JIA) compared to matched healthy peers. The secondary objective was to explore the relationship between HGS and JIA disease activity, disability, and quality of life. Methods: This study involved 23 patients with JIA and 46 age and sex matched healthy controls. Hand held dynamometer was used to evaluate HGS for all study participants. Anthropometric parameters for all study participants were measured. Disease activity, physical function, and quality of life were assessed for the JIA group using juvenile arthritis disease activity score (JADAS-27), juvenile arthritis functionality scale (JAFS), and pediatric quality of life inventory (PedsQL) respectively. Laboratory marker of inflammation, erythrocyte sedimentation rate (ESR), and plain radiography of hands were performed for all patients. Results: Hand grip strength of children and adolescents with JIA was significantly weaker compared to matched controls (p < 0.001). Hand grip strength had a significant inverse correlation with JADAS-27 (r= -0.467, p = 0.025), JAFS (r= - 0.650, p = 0.001) and a significant direct correlation with PedsQL (r= 0.438, p = 0.036). In addition, HGS was negatively correlated with ESR and duration of morning stiffness (r = -0.489, p = 0.018 and r= -0.201, p = 0.359, respectively). HGS was detected as an independent predictor of disease activity, disability, and quality of life in JIA patients in multivariate linear regression. Conclusions: Assessment of HGS could be a simple non-invasive tool for assessing disease activity, disability and quality of life in JIA patients in clinical practice.