Secondary consequences of juvenile idiopathic arthritis in children and adolescents with knee involvement: physical activity, adiposity, fitness, and functional performance

Bone health and physical activity in adolescents with juvenile idiopathic arthritis: a cross-sectional case-control study

BACKGROUND

Adolescents with juvenile idiopathic arthritis (JIA) tend to engage in less physical activity than their typically developing peers. Physical activity is essential for bone development and reduced physical activity may detrimentally effect bone health. Thus, we examined differences in total body bone mineral content (BMC) and areal bone mineral density (aBMD) between adolescents with JIA and adolescent controls without JIA. We also examined associations between moderate-to-vigorous physical activity (MVPA), lean mass, and bone outcomes.

METHODS

Participants included 21 adolescents with JIA (14 females, 7 males) and 21 sex- and age-matched controls aged 10-20 years. Assessments included: height; weight; triple-single-leg-hop distance (TSLH); MVPA by accelerometry; and total body BMC, aBMD, and lean mass measured using dual X-ray absorptiometry. Height-adjusted z-scores were calculated for BMC and aBMD and used for all analyses. Multiple linear mixed effects models examined group differences in BMC and aBMD, adjusting for sex, maturity, MVPA, TSLH, and lean mass. Participants clusters, based on sex and age (within 18 months), were considered random effects.

RESULTS

Adolescents with JIA had lower total body aBMD z-scores [β (95% CI); -0.58 (-1.10 to -0.07), p = 0.03] and BMC z-scores [-0.47 (-0.91 to -0.03), p = 0.04] compared with controls. Mean daily MVPA was 22.0 min/day lower in adolescents with JIA than controls; however, MVPA was not associated with aBMD [-0.01 (-0.01 to 0.01), p = 0.32] or BMC [0.00 (-0.01 to 0.00), p = 0.39]. Lean mass was positively associated with aBMD [0.05 (0.01 to 0.09) g/cm2, p = 0.03] and BMC [0.06 (0.03 to 0.10) g, p < 0.001].

CONCLUSION

Adolescents with JIA had lower total body aBMD and BMC compared with sex- and age-matched controls without JIA. Group differences in bone outcomes were not associated with the lower MVPA participation of adolescents with JIA. Despite this, physical activity should still be encouraged as it promotes physical well-being.

Determinants of physical activity level in children and adolescents with juvenile idiopathic arthritis

OBJECTIVE

One of the most frequently discussed physical parameters in juvenile idiopathic arthritis (JIA) is physical activity level. There is limited evidence about determinants of physical activity level in JIA. In this study, we aimed to investigate the determinants of physical activity level in children and adolescents with JIA.

MATERIALS AND METHODS

Thirty-two JIA patients and 18 age- and sex-matched healthy individuals were included in the study. The age range was 8-18 years. Sociodemographic and clinical data of the participants were recorded. In both groups, anthropometry, fatigue, pain, knee extension muscle strength, gait variables, functional exercise capacity assessed by six-minute walk test (6MWT), and arterial stiffness were evaluated. Physical activity level was assessed by an accelerometer.

RESULTS

The disease activity level of the patients was low. Pain and fatigue scores were significantly higher in the JIA group compared to healthy controls (p < 0.05). Walking speed, physical activity level, time spent in low-intensity physical activity, time spent in moderate-to-vigorous-intensity physical activity, and 6MWT distance were significantly lower than in healthy controls (p < 0.05). Quadriceps muscle strength and arterial stiffness assessment results were similar in both groups (p > 0.05). In the JIA group, there was a positive correlation between physical activity and age, height, fat-free body mass, quadriceps muscle strength, and 6MWT distance (p < 0.05). Also, there was a negative correlation between physical activity and pain, fatigue, and cadence. Physical activity level was independently associated with 6MWT distance (42.9% of the variability).

CONCLUSION

In mildly affected JIA patients, gait speed, functional exercise capacity, and physical activity level are affected. Functional exercise capacity is a determinant of physical activity level in JIA.

Cardiorespiratory fitness assessed with cardiopulmonary exercise testing in patients with juvenile idiopathic arthritis: a systematic review and meta-analysis

OBJECTIVES

JIA is the most common type of arthritis in children and adolescents, causing joint damage, chronic pain and disability. Deconditioning is also prevalent in patients with JIA due to both inactivity and the disease progression, resulting in reduced cardiorespiratory fitness (CRF). We aimed to evaluate CRF of patients with JIA compared with healthy controls.

METHODS

This is a systematic review and meta-analysis of studies using cardiopulmonary exercise testing (CPET) to examine differences in determinants of CRF between patients with JIA vs healthy controls. The primary outcome was peak oxygen uptake (VO2peak). Literature search involved PubMed, Web of Science and Scopus databases, manual search of article references and grey literature. Quality assessment was undertaken with Newcastle-Ottawa Scale.

RESULTS

From 480 literature records initially retrieved, eight studies (538 participants) were included in final meta-analysis. VO2peak was significantly lower in patients with JIA compared with controls [weighted mean difference (WMD): -5.95 ml/kg/min (95% CI -9.26, -2.65)]. Exercise duration and VO2peak (% predicted) were found to be significantly impaired in patients with JIA compared with controls [standardized mean difference: -0.67 (95% CI -1.04, -0.29) and WMD: -11.31% (95% CI -20.09, -2.53), respectively], while no significant differences were found in maximum heart rate.

CONCLUSION

VO2peak and other CPET variables were lower in patients with JIA compared with controls, indicating reduced CRF in the former. Overall, exercise programs for patients with JIA should be promoted as part of their treatment to improve physical fitness and reduce muscle atrophy.

PROSPERO REGISTRATION

CRD42022380833.

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

BACKGROUND

In recent years, biologic drug therapies have altered the course of juvenile idiopathic arthritis (JIA) possibly also improving the patients' physical fitness. However, studies measuring both cardiorespiratory and muscular fitness in children with JIA are sparse and have failed to show consistent results. Our aim was to assess both cardiorespiratory and neuromuscular fitness and contributing factors in children and adolescents with JIA in the era of biologic drug therapies.

METHODS

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

RESULTS

Means (± SD) of maximal workload (W_max/kg) and peak 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_peak/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 results were lower in JIA patients than in 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) in JIA patients compared to controls. Physical activity and cardiorespiratory or neuromuscular fitness were not associated with disease activity.

CONCLUSIONS

JIA patients were physically less active and had lower cardiorespiratory and neuromuscular fitness than their same aged controls with no JIA. Therefore, JIA patients should be encouraged to engage in physical activities as a part of their multidisciplinary treatment protocols to prevent adverse health risks of low physical activity and fitness.

Nutritional Aspects of Juvenile Idiopathic Arthritis: An A to Z for Dietitians

Juvenile idiopathic arthritis (JIA) represents a chronic, autoimmune, rheumatic musculoskeletal disease with a diagnosis before 16 years of age. Chronic arthritis is a common manifestation in all JIA subtypes. The nature of JIA, in combination to its therapy often results in the development of nutrition-, gastrointestinal (GI)- or metabolic-related issues. The most-common therapy-related nutritional issues involve methotrexate (MTX) and glucocorticosteroids (GCC) adverse events. MTX is a folic acid antagonist, thus supplementation with folic acid in required for improving GI side effects and correcting low serum levels. On the other hand, long-term GCC administration is often associated with hyperglycemia, insulin resistance and growth delay. This relationship is further aggravated when more joints are affected and greater doses of GCC are being administered. Apart from stature, body mass index z-scores are also suboptimal in JIA. Other signs of malnutrition include decreased phase angle and muscle mass, especially among patients with polyarthritis JIA. Evidence also points to the existence of an inverse relationship between disease activity and overweight/obesity. Specific dietary patterns, including the anti-inflammatory diet, might confer improvements in selected JIA outcomes, but the level of available research is yet insufficient to draw safe conclusions. The majority of patients exhibit suboptimal vitamin D status; hence, supplementation is recommended. Collectively, the evidence indicates that, due to the age of onset and the complexity of the disease, along with its pharmacotherapy, children with JIA are prone to the development of several nutritional problems, warranting expert monitoring. Vitamin deficiencies, oral and GI-problems limiting dietary intake, faltering growth, overweight and obesity, physical inactivity, or impaired bone health are among the many nutritional issues in JIA requiring dietitian support.

Physical Activity Influences Health-Related Quality of Life in Adults with Juvenile Idiopathic Arthritis

This cross-sectional study aimed to evaluate the impact of physical activity and physical fitness on the health-related quality of life (HQoL) of adult patients with Juvenile Idiopathic Arthritis (JIA). Fifty-nine JIA patients and sixty healthy individuals participated in this study. All individuals had the following evaluations performed: body composition (electrical bioimpedance), physical fitness (6 min walk test (6MWT)), physical activity level (International Physical Activity Questionnaire (IPAQ)), and HQoL (Quality of Life Questionnaire in relation to Health-Short Form (SF36)). Thirty-nine (66%) JIA patients were considered sedentary compared with 15 (25%) in the control group (p < 0.01). JIA patients had a lower HQoL compared with the control group in all variables studied (p < 0.05). JIA patients who were very physically active had better HQoL conditions in the categories of functional capacity (p = 0.001), limitations by physical aspects (p = 0.003), and emotional aspects (p = 0.002) compared with sedentary patients. JIA patients had more cardiovascular abnormalities and walked shorter distances compared with healthy controls in the 6MWT. In conclusion, we observed that HQoL was reduced in adults with JIA. A high percentage of JIA patients were sedentary with lower physical fitness, but physically active patients had a better HQoL than sedentary patients. The duration of physical activity, rather than intensity, influenced the mental aspects of HQoL.

Consequences of Juvenile Idiopathic Arthritis on Single Leg Squat Performance in Youth

OBJECTIVE

Juvenile idiopathic arthritis (JIA) affects body structure and function outcomes that may increase the risk of acute joint injury. The purpose of this study was to examine single leg squat (SLS) biomechanics for youth with JIA and their healthy peers. The study design was a matched pair cohort study.

METHODS

Sixty-five youth (JIA n = 30; control n = 35) participated in this ethics-approved study. Participants performed 3 sets of 5 consecutive SLS tasks. Disease activity and functional status were assessed using the Juvenile Arthritis Disease Activity Score and Child Health Assessment Questionnaire. Indexed (most-affected leg [JIA]; dominant leg [control]) and contralateral extremity biomechanics were obtained using a 12-camera system. Outcomes included hip flexion/extension (FE), adduction/abduction (AA), and internal/external (IE) rotation range of motion (ROM). Data were analyzed using a multivariate random coefficient model in R (α⍺ = 0.05).

RESULTS

A total of 29 matched pairs were analyzed. Youth with JIA had low disease activity and performed the SLS with a more internally rotated hip (indexed leg P = 0.023, β = -1.9°). Female participants displayed greater hip FE (indexed leg P = 0.015, β = -4.3°; contralateral leg P = 0.005, β = -4.8°) and IE ROM (indexed leg P = 0.021, β = -2.1°) than male participants. Associations were observed for body mass index and hip IE ROM (contralateral leg P = 0.001, β = -0.4°), knee flexion angle, and hip FE ROM (indexed leg P = 0.001, β = 0.4°; contralateral leg P = 0.001, β = 0.5°) and AA (indexed leg P = 0.010, β = 0.1°; contralateral leg P = 0.002, β = 0.2°).

CONCLUSION

This study identified functional alterations for an SLS in youth with JIA. These findings support the use of physical therapy as part of a multidisciplinary management approach, to restore normal hip posture and movement.