Auxological dynamics of children with Juvenile Idiopathic Arthritis: a mixed-longitudinal study from Chandigarh, North India.

Objective: To study growth pattern of weight and length/height in male and female children with Juvenile Idiopathic Arthritis (JIA). Methods: A total of 348 patients (boys: 182, girls: 166) aged 1 to 18 years, diagnosed as cases of JIA and categorized into oligoarthritis, polyarthritis and systemic arthritis were enrolled in this mixed-longitudinal study from Pediatric Rheumatology Clinic of Advanced Pediatrics Centre, PGIMER, Chandigarh, India. Weight and length/height measurements were recorded at approximately 6 monthly intervals in Growth Laboratory/Growth Clinic of the department over a period of 13 years. Mean (SD) for weight and length/height were computed. Unpaired Student's t-test was employed to ascertain gender differences. Analysis of variance and post-hoc Bonferroni tests were applied to evaluate inter-group differences. Results: A regular increase in weight and length/height of all children representing three types of JIA was noticed throughout the study period. Maximum growth impairment was seen in patients with systemic JIA. Children with oligoarthritis were least affected. Boys with oligoarthritis, measured lighter and shorter than girls. Gender differences for children with polyarthritis demonstrated inconsistent trends. Boys with systemic JIA generally measured lighter than girls. Boys with systemic JIA measured taller than girls upto 4 years and thereafter they remained shorter till 14 years. Conclusions: As compared to normal children (2000 CDC), impaired weight and length/height growth attainments were recorded in oligoarthritis, polyarthritis and systemic JIA patients throughout the study span. However, the magnitude of this impairment appears to be related to the subtype of JIA.