Aerobic capacity and disease activity in children, adolescents and young adults with juvenile idiopathic arthritis (JIA)

Screening for juvenile idiopathic arthritis associated uveitis with laser flare photometry in the pediatric rheumatology office: a prospective observational study

BACKGROUND

Juvenile Idiopathic Arthritis (JIA) Associated Uveitis (JIA-U) remains one of the most serious complications of JIA in children. Historically, pediatric JIA is diagnosed by an Optometrist or Ophthalmologist; however, barriers to scheduling increase wait times that may delay diagnosis and treatment. The purpose of this study was to evaluate laser flare photometry (LFP) use to diagnose JIA-U in the Pediatric Rheumatology clinic for patients with JIA.

METHODS

This prospective, observational study assessed pediatric patients diagnosed with JIA without a previous history of uveitis between January 2020 and September 2022. All patients underwent at least one evaluation of both eyes using a Kowa FM-600 laser flare photometer during a routine Rheumatology appointment, as well as a standard slit lamp examination (SLE) by optometry or ophthalmology during routine clinical care. Data collected at patient visits included demographics, JIA characteristics, treatment, LFP readings, and anterior chamber (AC) cell grade score utilizing the SUN grading system. Data were summarized using descriptive analyses and the uveitis false positive rate was calculated.

RESULTS

The study cohort included 58 pediatric patients diagnosed with JIA. The mean age was 8.4 years (1.2-16.3 years) at diagnosis and 11.9 (4.8-16.5 years) at enrollment. The mean duration of disease at time of enrollment was 42 months (range; 0-157 months). Participants were predominantly female (n = 43, 74.1%) and white/Caucasian race (n = 37, 63.8%). The most common JIA subtypes included persistent oligoarticular JIA (n = 19, 32.8%), and RF negative polyarticular JIA (n = 12, 20.7%). There were 12 ANA positive patients (20.7%). At enrollment, 16 patients (27.6%) were not on medications, with 20 (34.5%) on methotrexate, 20 (34.5%) on adalimumab, 6 (10.3%) on tocilizumab, and 5 (8.6%) on etanercept. During the study period, no eye exams detected active uveitis based on SLE with a SUN grade over 0. However, of the 135 LFP readings, 131 (97.0%) were normal, yielding a false positive rate of 3% (95% CI: 0.8%, 7.4%).

CONCLUSIONS

LFP is a non-invasive tool that can be utilized in the pediatric rheumatology clinic to evaluate for JIA-U. There is a low false positive rate of LFP when compared with standard slit lamp exam.

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.

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.

Reference Values for the Six Minute Walk Test in Children with Juvenile Idiopathic Arthritis

AIMS

To (1) describe six-minute walk test (6MWT) reference values for children with Juvenile Idiopathic Arthritis (JIA) and (2) explore predictors of 6MWT distance. A secondary objective was to determine how 6MWT distances of children with JIA compare to those of children without JIA reported in the literature.

METHODS

Demographic, clinical, height, weight and 6MWT data were extracted from clinical records of 120 children with JIA (70.8% female, mean age=12.4 ± 3.2 years) who attended a follow-up rheumatology clinic. A total of 272 6MWTs were included in the analyses. Linear mixed effects modeling was used to determine the relationship between predictive variables and 6MWT distance. 6MWT distances were compared to predicted values using published equations for estimating 6MWT distances in children without JIA.

RESULTS

Height, weight, and age were predictive of 6MWT distance (R² = 0.62). Mean 6MWT distances for children with JIA were lower than those reported for children without JIA (p < 0.001). Mean 6MWT distance was 84% and 78% of predicted values for children without JIA.

CONCLUSION

The reference values and associated predictive model have application for assessing exercise capacity in children with JIA.

The importance of lower extremity involvement type on exercise performances, function, and quality of life in peripheral predominant forms of juvenile idiopathic arthritis

BACKGROUND

Juvenile idiopathic arthritis (JIA) can cause reduced exercise capacity, deterioration in functional activities, and poor health-related quality of life. This study aims to objectively reveal lower extremity involvement in the peripheral predominant forms of juvenile idiopathic arthritis through qualitative evaluations and to determine the effects of these involvements on exercise, function, and quality of life.

METHODS

Thirty-two patients with a history of peripheral arthritis and aged between 7 and 16 years participated in the study. Demographics, JIA subtype, disease duration, arthritis and deformities of the lower extremity, disease activity score, 6-min walk test (6MWT), cycling exercise test (CYC-E), childhood health assessment questionnaire (CHAQ), and pediatric quality of life inventory (PedsQoL) scores were recorded. In case of clinical suspicion of arthritis, an ultrasonographic examination was performed for a definitive diagnosis. Regression analyses were performed to explore the most associated lower extremity involvement and patient characteristics for each of the dependent variables including 6MWT, CYC-E, CHAQ, and PedsQoL.

RESULTS

Of the total number of patients, with a mean age of 12.91 (SD 2.37) years, 28.1% had knee arthritis, 15.6% foot arthritis, 12.5% hip arthritis, and 37.5% lower extremity deformity. The parameters that were most associated with CHAQ and PedsQoL were hip and knee arthritis, whereas CYC-E was found to be most associated with knee arthritis and height, and 6MWT was found to be most associated with hip arthritis, knee arthritis, and demographic characteristics.

CONCLUSION

This study emphasizes the importance of hip and knee arthritis, which are among the determinants of walking endurance, function, and quality of life; and knee arthritis, which is among the determinants of cycling performance in JIA with lower extremity involvement.