Impaired cardiorespiratory and neuromuscular fitness in children and adolescents with juvenile idiopathic arthritis: a cross-sectional case-control study in the age of biological drug therapies – PubMed

Background:

In recent years, biologic drug therapies have altered the course of juvenile idiopathic arthritis (JIA) and may also improve patients’ physical fitness. However, studies measuring both cardiorespiratory and muscular fitness in children with JIA are sparse and have not shown consistent results. Our aim was to assess both cardiorespiratory and neuromuscular fitness and contributing factors in children and adolescents with JIA in the age of biologic drug therapies.

Methods:

This cross-sectional study consisted of 73 JIA patients (25 boys, 48 ​​girls) ranging in age from 6.8 to 17.5 years and 73 healthy, age- and sex-matched controls studied from 2017 to 2019. Cardiorespiratory fitness was assessed by maximal ergospirometry and neuromuscular fitness by speed, agility, balance, and muscle strength tests.

Results:

Mean values ​​(± SD) of the maximum workload (W_max/kg) and maximal oxygen uptake (VO2_peak/kg,) were lower in JIA patients than in controls (W_max/kg: 2.80 ± 0.54 vs. 3.14 ± 0.50 watts, p<0.01; VO2_tip/kg: 38.7 ± 7.53 vs. 45.8 ± 6.59 ml/min/kg, p<0.01). Shuttle run, sit-up, and standing long jump test scores were lower in JIA patients than controls (p<0.01). Mean (± SD) daily activity was lower (89.0 ± 44.7 vs. 112.7 ± 62.1 min/day, p<0.05) and sedentary time was higher (427 ± 213 vs. 343 ± 211 min/day, p<0.05). JIA patients compared to controls. Physical activity and cardiorespiratory or neuromuscular fitness were not associated with disease activity.

Conclusions:

JIA patients were less physically active and had lower cardiorespiratory and neuromuscular fitness than their non-JIA-matched controls. Therefore, JIA patients should be encouraged to engage in physical activity as part of their multidisciplinary treatment protocols to avoid adverse health risks from low physical activity and fitness.