Congruence between polysomnography obstructive sleep apnea and the pediatric sleep questionnaire: fatigue and health-related quality of life in juvenile idiopathic arthritis

Temporal Daily Relationships Between Sleep and Pain in Adolescents With Systemic Lupus Erythematosus

INTRODUCTION

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder characterized by recurrent episodes of pain. This study aimed to describe the temporal daily relationships between sleep and pain in adolescents with SLE.

METHOD

Twenty-three adolescents with SLE recruited from a pediatric hospital wore actigraphy and completed diaries. Generalized estimating equation models were used.

RESULTS

On average, evening pain negatively predicted subsequent sleep quality that night, and, on average, sleep quality negatively predicted morning pain. Shorter total sleep time significantly predicted higher morning pain (95% confidence intervals [CI], -0.38 to -0.03, p = .02), whereas sleep efficiency and sleep quality were not significantly associated with morning pain (95% CI, -0.03 to 0.03; 95% CI, -0.08 to 0.06, respectively). Subsequent evening pain did not predict daily nighttime sleep DISCUSSION: Our findings suggest that sleep is a target for pain interventions to include among adolescents with SLE.

Pathways of sleep disturbances in juvenile idiopathic arthritis and recommendations for clinical management approaches: A critical review

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease affecting young people. It has a profound impact on their physical, mental and social lives, leading to long-term disability. With the growing awareness of the importance of sleep in all areas of functioning in young people, an emerging literature has drawn attention to the role of sleep in the pathogenesis of JIA. Sleep disturbances in children and adolescents with JIA arise from a wide range of symptoms and pathways, leading to a vicious cycle that exacerbates subclinical inflammation, symptoms and disease progression. Putative factors contributing to sleep disturbances include chronic inflammation, JIA-associated sleep disorders, JIA symptoms (e.g. pain), psychological comorbidities and potential circadian disruption, which may be exacerbated by the transition to adolescence. Here, we review these pathways and advocate key strategies and alternatives for sleep management in young people with JIA in clinical settings. We identify gaps in knowledge and suggest future directions to improve our understanding of JIA sleep disorders, including clinical trials investigating potential strategies to improve sleep health in this young population.

Fatigue and Quality of Life in Children with Hearing Loss or Obstructive Sleep Apnea

OBJECTIVE

To investigate the fatigue levels of children with hearing loss (HL) and obstructive sleep apnea (OSA), hypothesizing that the fatigue experienced by children with HL is under-recognized.

STUDY DESIGN

Cross-sectional survey.

METHODS

We identified children aged 2-18 with HL, OSA, sleep-disordered breathing (SDB), and controls from a pediatric otolaryngology clinic and sleep center. Children and/or parents completed the Pediatric Quality of Life Inventory Multidimensional Fatigue Scale (PedsQL MFS), Hearing Environments And Reflection on Quality of Life (HEAR-QL), and OSA-18.

RESULTS

Responses of 50 children with HL, 79 with OSA, and 18 with SDB were compared with those of 49 recruited controls (RC) and literature controls (LC). Children with HL or OSA had higher fatigue than controls in the PedsQL MFS self-reported (HL 65.4, OSA 54.7, RC 71.8, LC 80.5, p < 0.001) and parent-reported (HL 64.6, OSA 59.3, RC 75.2, LC 89.6, p < 0.001). Children with HL had Cognitive Fatigue similar to that of children with OSA (self 60.4 vs. 49.5, p = 0.170; parent 56.0 vs. 56.7, p = 0.998), though with decreased Sleep/Rest Fatigue (self 67.8 vs. 56.3, p = 0.033; parent 69.8 vs. 57.5, p = 0.001). Children with HL or OSA had lower disease-related quality of life (QOL) than controls in the HEAR-QL and OSA-18, respectively. Stratification with disease severity revealed no differences in fatigue.

CONCLUSION

Children with HL or OSA experience higher fatigue and lower QOL than controls. Similar Cognitive Fatigue in both groups suggests under-recognized fatigue in children with HL.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:443-451, 2024.

Mental Health and Cognitive Development in Symptomatic Children and Adolescents Scoring High on Habitual Snoring: Role of Obesity and Allergy

BACKGROUND

Obstructive sleep apnea can have a negative impact on children's and adolescents' neurocognitive abilities and hinder their academic and adaptive progress in academic, social, and/or behavioral dimensions. In this retrospective cross-sectional study, we investigated the influence of body weight conditions and allergy status on long-term mental health, cognitive development, and quality of life in children and adolescents who snored.

METHODS

The study sample included 47 subjects (age range 4.1 to 15.3 years) who exhibited high levels of snoring and underwent home-based polysomnography between 2015 and 2019. Follow-up assessments (3 years on average between baseline and follow-up) entailed phone interviews with the subject's parents/caregivers who completed three validated questionnaires investigating sleep, quality of life, and parental ratings.

RESULTS

We found a correlation between age at diagnosis and being retrospectively overweight and high levels of snoring. In addition to a higher risk of developing emotional symptoms (8.2% increase in retrospective overweight status for each unit increase in the emotional score at follow-up) and oppositional behavior (9% increase in retrospective overweight status for each unit of oppositional T points at follow-up), we also noted reduced long-term social symptoms (11% decrease in retrospective overweight status for each unit increase in the social score at follow-up) and cognitive symptoms (10.6% decrease in retrospective overweight status for each unit increase in the cognitive score at follow-up), as well as a 6.1% increase in retrospective allergy status for each unit increase in academic performance at follow-up.

CONCLUSIONS

Snoring can have negative impacts on mental health and cognitive development in the long term. Early detection and intervention for neuropsychological disorders is important in children and adolescents who score high on snoring. In the long term, the effects of snoring on neuropsychological disorders may vary based on previous body weight and allergy status.

Predictive Power of Oxygen Desaturation Index (ODI) and Apnea-Hypopnea Index (AHI) in Detecting Long-Term Neurocognitive and Psychosocial Outcomes of Sleep-Disordered Breathing in Children: A Questionnaire-Based Study

Pediatric obstructive sleep apnea can negatively affect children's neurocognitive function and development, hindering academic and adaptive goals. Questionnaires are suitable for assessing neuropsychological symptoms in children with sleep-disordered breathing. The study aimed to evaluate the effectiveness of using the Oxygen Desaturation Index compared to the Obstructive Apnea-Hypopnea Index in predicting long-term consequences of sleep-disordered breathing in children. We conducted a retrospective analysis of respiratory polysomnography recordings from preschool and school-age children (mean age: 5.8 ± 2.8 years) and followed them up after an average of 3.1 ± 0.8 years from the home-based polysomnography. We administered three validated questionnaires to the parents/caregivers of the children by phone. Our results showed that children with an Oxygen Desaturation Index (ODI) greater than one event per hour exhibited symptoms in four domains (physical, school-related, Quality of Life [QoL], and attention deficit hyperactivity disorder [ADHD]) at follow-up, compared to only two symptoms (physical and school-related) found in children with an Obstructive Apnea-Hypopnea Index greater than one event per hour at the time of diagnosis. Our study also found a significant correlation between the minimum SpO₂ (%) recorded at diagnosis and several outcomes, including Pediatric Sleep Questionnaire (PSQ) scores, physical, social, and school-related outcomes, and ADHD index at follow-up. These results suggest that the Oxygen Desaturation Index could serve as a valuable predictor of long-term symptoms in children with sleep-disordered breathing, which could inform treatment decisions. Additionally, measuring minimum SpO₂ levels may help assess the risk of developing long-term symptoms and monitor treatment outcomes.

Physical activity as a promising alternative for young people with juvenile idiopathic arthritis: Towards an evidence-based prescription

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in young people. Although biologics now enable most children and adolescents with JIA to enjoy clinical remission, patients present lower physical activity and spend more time in sedentary behavior than their healthy counterparts. This impairment probably results from a physical deconditioning spiral initiated by joint pain, sustained by apprehension on the part of both the child and the child's parents, and entrenched by lowered physical capacities. This in turn may exacerbate disease activity and lead to unfavorable health outcomes including increased risks of metabolic and mental comorbidities. Over the past few decades, there has been growing interest in the health benefits of increased overall physical activity as well as exercise interventions in young people with JIA. However, we are still far from evidence-based physical activity and / or exercise prescription for this population. In this review, we give an overview of the available data supporting physical activity and / or exercise as a behavioral, non-pharmacological alternative to attenuate inflammation while also improving metabolism, disease symptoms, poor sleep, synchronization of circadian rhythms, mental health, and quality of life in JIA. Finally, we discuss clinical implications, identify gaps in knowledge, and outline a future research agenda.

The complexities of the sleep-pain relationship in adolescents: A critical review

Chronic pain is a common and disabling condition in adolescents. Disturbed sleep is associated with many detrimental effects in adolescents with acute and chronic pain. While sleep and pain are known to share a reciprocal relationship, the sleep-pain relationship in adolescence warrants further contextualization within normally occurring maturation of several biopsychological processes. Since sleep and pain disorders begin to emerge in early adolescence and are often comorbid, there is a need for a comprehensive picture of their interrelation especially related to temporal relationships and mechanistic drivers. While existing reviews provide a solid foundation for the interaction between disturbed sleep and pain in youth, we will extend this review by highlighting current methodological challenges for both sleep and pain assessments, exploring the recent evidence for directionality in the sleep-pain relationship, reviewing potential mechanisms and factors underlying the relationship, and providing direction for future investigations. We will also highlight the potential role of digital technologies in advancing the understanding of the sleep and pain relationship. Ultimately, we anticipate this information will facilitate further research and inform the management of pain and poor sleep, which will ultimately improve the quality of life in adolescents and reduce the risk of pain persisting into adulthood.

Restricted upper airway dimensions in patients with dentofacial deformity from juvenile idiopathic arthritis

BACKGROUND

This retrospective, cross-sectional study aimed to assess the pharyngeal airway dimensions of patients with juvenile idiopathic arthritis (JIA) and moderate/severe JIA-related dentofacial deformity (mandibular retrognathia/micrognathia), and compare the results with JIA patients with a normal mandibular appearance and a group of non-JIA patients.

METHODS

Seventy-eight patients were retrospectively included in a 1:1:1 manner as specified below. All patients had previously been treated at the Section of Orthodontics, Aarhus University, Denmark. All had a pretreatment cone beam computed tomography (CBCT). Group 1 (JIA+); 26 JIA patients with severe arthritis-related dentofacial deformity and mandibular retrognathia/micrognathia. Group 2 (JIA-); 26 JIA patients with normal mandibular morphology/position. Group 3 (Controls); 26 non-JIA subjects. Dentofacial morphology and upper airway dimensions, excluding the nasal cavity, were assessed in a validated three-dimensional (3D) fashion. Assessment of dentofacial deformity comprised six morphometric measures. Assessment of airway dimensions comprised nine measures.

RESULTS

Five morphometric measures of dentofacial deformity were significantly deviating in the JIA+ group compared with the JIA- and control groups: Posterior mandibular height, anterior facial height, mandibular inclination, mandibular occlusal inclination, and mandibular sagittal position. Five of the airway measurements showed significant inter-group differences: JIA+ had a significantly smaller nasopharyngeal airway dimension (ad2-PNS), a smaller velopharyngeal volume, a smaller minimal cross-sectional area and a smaller minimal hydraulic diameter than JIA- and controls. No significant differences in upper airway dimensions were seen between JIA- and controls.

CONCLUSION

JIA patients with severe arthritis-related dentofacial deformity and mandibular micrognathia had significantly restricted upper airway dimensions compared with JIA patients without dentofacial deformity and controls. The restrictions of upper airway dimension seen in the JIA+ group herein were previously associated with sleep-disordered breathing in the non-JIA background population. Further studies are needed to elucidate the role of dentofacial deformity and restricted airways in the development of sleep-disordered breathing in JIA.

A 3D CBCT Analysis of Airway and Cephalometric Values in Patients Diagnosed with Juvenile Idiopathic Arthritis Compared to a Control Group

Introduction: The temporomandibular joint (TMJ) is affected in 30–45% of juvenile idiopathic arthritis (JIA) patients, with all JIA subtypes at risk for TMJ involvement. JIA patients with TMJ involvement may present with altered craniofacial morphology, including micrognathia, mandibular retrognathia, a hyperdivergent mandibular plane angle, and skeletal anterior open bite. These features are also commonly present and associated with non-JIA pediatric patients with obstructive sleep apnea (OSA). Materials and Methods: The study was comprised of a group of 32 JIA patients and a group of 32 healthy control subjects. CBCT images were taken for all patients and were imported into Dolphin Imaging software. The Dolphin Imaging was used to measure the upper airway volumes and the most constricted cross-sectional areas of each patient. Cephalometric images were rendered from the CBCT data for each patient, and the following cephalometric values were identified: SNA angle, SNB angle, ANB angle, anterior facial height (AFH), posterior facial height (PFH), mandibular plane angle (SN-MP), FMA (FH-MP), overjet (OJ), and overbite (OB). Airway volumes, the most constricted cross-sectional area values, and cephalometric values were compared between the JIA and control groups. Results: For airway values, statistically significant differences were seen in the nasopharynx airway volume (p = 0.004), total upper airway volume (p = 0.013), and the most constricted cross-sectional area (p = 0.026). The oropharynx airway volume was not statistically significant (p = 0.051). For cephalometric values, only the posterior facial height showed a statistically significant difference (p = 0.024). Conclusions: There was a significant difference in airway dimensions in the JIA patients as compared to the control patients. In addition, the posterior facial dimensions seem to be affected in JIA patients. The ODDs ratio analysis further corroborated the findings that were significant.

Sleep Health Assessment and Treatment in Children and Adolescents with Chronic Pain: State of the Art and Future Directions

Sleep is interrelated with the experience of chronic pain and represents a modifiable lifestyle factor that may play an important role in the treatment of children and adolescents with chronic pain. This is a topical review of assessment and treatment approaches to promote sleep health in children and adolescents with chronic pain, which summarizes: relevant and recent systematic reviews, meta-analyses, and methodologically sound prospective studies and clinical trials. Recommendations are provided for best practices in the clinical assessment and treatment of sleep health in youth with chronic pain. This overview can also provide researchers with foundational knowledge to build upon the best evidence for future prospective studies, assessment and intervention development, and novel clinical trials.

Pediatric quality of life multidimensional fatigue scale (PedsQL-MFS) detects the effects of a 3-week Inpatient body weight reduction program for children and adolescents with obesity

BACKGROUND

Fatigue is a frequent complaint amongst children and adolescents with obesity, and it interferes with adherence to dietary and exercise regimes that could reduce obesity. The present study evaluated the effect of an inpatient 3-week body weight reduction program on body weight and fatigue.

METHOD

One hundred children and adolescents with obesity (64% female; aged 11-18 years) undertook an inpatient program of personalized diet, daily exercise, education, and counselling.

RESULTS

The sample evidenced a mean reduction in body mass (females: ΔM = 4.3 (sd = 2.1) kg, p < .001), males: ΔM = 6.2 (sd = 2.6) kg, p < .001), BMI standard deviation score (females: ΔM = 0.17 (sd = 0.07), males: ΔM = 0.24 (sd = 0.08), p < .001) and fatigue (females: ΔM = 7.8 (sd = 9.7), males: ΔM = 5.0 (sd = 6.9), p < .001) as measured by the Pediatric Quality of Life Multidimensional Fatigue Scale (PedsQL-MFS) and improvements on the Attention problems subscale of the Youth Self Report (total sample: ΔM = 0.89 (sd = 2.44), p < .001). Reliable change analyses revealed fatigue changes were achieved by up to 34% females and 17% males, but the majority did not achieve reliable change and changes in fatigue were not correlated with changes in body mass.

CONCLUSIONS

The program achieved clinically significant improvements in some children and adolescents. Future studies should explore predictors of treatment responsiveness. Trial registration Observational study. Not registered.

Patients with juvenile idiopathic arthritis are at increased risk for obstructive sleep apnoea: a population-based cohort study

BACKGROUND AND OBJECTIVES

Juvenile idiopathic arthritis (JIA), an autoimmune disease, has been proposed to be comorbid with obstructive sleep apnoea (OSA). We aimed at testing the hypothesis that patients with JIA may presented with high risk of OSA in a cohort study.

SUBJECTS AND METHODS

This is a cohort study including patients with JIA from 1999 to 2013 identified from a longitudinal health registry. A matched non-JIA control group was also included. The primary outcome variable was presence of OSA. A Cox proportional hazard model was developed to estimate the risk of OSA in patients with JIA. A cumulative probability model was adopted to assess the time-dependent effect of JIA on OSA development, implying a causal link of the association.

RESULTS

A total of 2791 patients with JIA were included, and 11 164 individuals without JIA were selected as matched controls. A total of 95 included subjects had OSA: 31 in the JIA group and 64 in the control group. Patients with JIA were more likely to have OSA compared with controls (adjusted hazard ratio, aHR = 1.922, 95% confidence interval [CI] = 1.244-2.970). The incidence of developing OSA was particularly high among patients with JIA-associated deformity that presented at age 18-30 years (aHR = 1.993, 95% CI = 1.277-3.113) and males (aHR = 1.786, 95% CI = 1.097-2.906). The risk of developing OSA increased over 60 months (aHR = 2.523, 95% CI = 1.322-4.815) of follow-up after the JIA diagnosis.

CONCLUSIONS

Patients with JIA have a significantly increased risk of developing OSA compared with matched individuals without JIA.

Sleep in children and adolescents with juvenile idiopathic arthritis: a systematic review and meta-analysis of case-control studies

STUDY OBJECTIVES

Juvenile idiopathic arthritis (JIA) is one of the most common pediatric rheumatic disease. However, sleep alteration associated with this auto-immune disease remain unclear. We aimed in this systematic review and meta-analysis to compare sleep duration, quality, and architecture in JIA subjects with those in their healthy peers.

METHODS

Systematic search performed in PubMed, EMBase, Cochrane, and PsycINFO databases included 19 studies in the qualitative synthesis of which 10 met the inclusion criteria for the meta-analysis.

RESULTS

Pooled results from subjective methods indicated pronounced sleep disturbances and complaints in youth with JIA compared with their healthy counterparts. This was further confirmed by Increased difficulty maintaining sleep (wake after sleep onset; SMD: -0.69; CI: -1.29; -0.09, p =0.02) and a tendency to increased difficulty initiating sleep (sleep onset latency; SMD: -0.29; CI: -0.60; 0.03, p =0.07). There were no remarkable differences in sleep duration or sleep architecture between JIA patients and healthy controls. High heterogeneity was found for several outcomes. This could be explained by the different methods used as well as associated sleep disorders, medication and comorbidities.

CONCLUSIONS

Although included studies were methodologically diverse, the summarized results of our review and meta-analysis bring evidence that children with JIA present more fragmented sleep compared to healthy peers. Thereby, the implementation of strategies to manage and improve sleep in this population are needed and might have a beneficial effect on the symptoms and functions of JIA.

Sleep Deficiency and Pediatric Chronic Pain

Sleep deficiency in children is a public health concern, and it is highly comorbid in pediatric chronic pain conditions. Children may be particularly vulnerable to the deleterious effects of sleep deficiency, because comorbid sleep deficiency in chronic pain may further exacerbate already existent symptoms of pain, anxiety, depressions, daytime function, and increase health care use. Sleep deficiency is modifiable and integrating human-centered approaches into the development of sleep interventions is a pragmatic approach to partner with parents and children to provide them with the knowledge, motivation, and skills for setting and achieving goals, adapting to setbacks, and problem solving.

Diagnostic accuracy of screening questionnaires for obstructive sleep apnea in children: A systematic review and meta-analysis

This systematic review and meta-analysis evaluated the diagnostic accuracy of screening questionnaires for pediatric obstructive sleep apnea (OSA). Studies comparing any questionnaire with polysomnography for OSA detection in subjects aged ≤18 y were considered eligible for qualitative analysis. The quality assessment of diagnostic accuracy studies (QUADAS-2) tool was used for bias assessment. Only questionnaires adopted by at least four studies using the currently accepted diagnostic threshold of apnea-hypopnea index (AHI) ≥1 were included for further selective quantitative analyses. A bivariate meta-analysis was performed to calculate sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio; summary receiver operator characteristic curves were constructed. 37 studies (20 questionnaires) were eligible for qualitative analysis; none were considered of low quality. Among these articles, 13 studies and two questionnaires (sleep-related breathing disorder scale of the pediatric sleep questionnaire (SRBD-PSQ) and OSA-18) satisfied the criteria for quantitative synthesis. SRBD-PSQ had higher sensitivity (0.76) than OSA-18 (0.56), while OSA-18 exhibited higher specificity (0.73) than SRBD-PSQ (0.43). SRBD-PSQ performed well and was the most sensitive screening questionnaire using the diagnostic threshold of AHI ≥1 for pediatric OSA. However, further well-designed studies are still required to assess the role of SRBD-PSQ in real-world clinical populations.

Diagnostic meta-analysis of the Pediatric Sleep Questionnaire, OSA-18, and pulse oximetry in detecting pediatric obstructive sleep apnea syndrome

The aim of this meta-analysis was to compare the pooled sensitivity and specificity of the Pediatric Sleep Questionnaire (PSQ), Obstructive Sleep Apnea Questionnaire (OSA-18), and pulse oximetry (PO) according to OSAS severity. Three electronic databases were searched for studies evaluating sensitivity and specificity of the three tools against the apnea-hypopnea index measured using overnight in-laboratory or in-home polysomnography in children and adolescents from inception until January 11, 2020. A random-effects bivariate model was used to estimate the summary sensitivity and specificity of the tools. We identified 39 studies involving 6131 clinical and community children (aged 2.9-16.7 y). The PSQ exhibited the highest sensitivity (74%) for detecting symptoms of mild pediatric OSAS. The PSQ and PO had comparable sensitivity in screening moderate and severe pediatric OSAS (0.82 and 0.89 vs 0.83 and 0.83, respectively). PO yielded superior specificity in detecting mild, moderate, and severe pediatric OSAS (86%, 75%, and 83%, respectively) than did the PSQ and OSA-18 (all p < 0.05). Age, percentage of girls, index test criteria, methodology quality, and sample size significantly moderated sensitivity and specificity. For early detection of pediatric OSAS, the combined use of PSQ and PO is recommended when polysomnography is not available. PROSPERO REGISTRATION NUMBER: CRD42018090571.

The Interrelationship between Sleep and Chronic Pain in Adolescents

Over half of youth with chronic pain report sleep deficiency including difficulties falling asleep, maintaining sleep, feeling unrested, and experiencing short sleep duration. Sleep deficiency has been shown to play a causal role in the development or worsening of chronic pain, and is associated with a variety of negative consequences for youth with chronic pain. The purpose of this review is to provide a summary of the literature on the interrelationship of sleep and chronic pain in adolescents. We review the impact and prevalence of sleep disturbances, conceptual models of the interrelationship of sleep and pain, biobehavioral mechanisms and risk factors, sleep assessment, and treatment of sleep deficiency and chronic pain in adolescents. Our recommendations for future research include understanding biobehavioral mechanisms that underlie the link between chronic pain and sleep deficiency to help guide development and testing of treatments for co-occurring pain and sleep disturbance in adolescents.

Total Sleep Time and BMI z-score Are Associated With Physical Function Mobility, Peer Relationship, and Pain Interference in Children Undergoing Routine Polysomnography: A PROMIS Approach

INTRODUCTION

Sleep disturbance, especially obstructive sleep apnea (OSA) and inadequate sleep, adversely affect various health-related quality of life (HR-QoL) domains in adults. Few studies have addressed problems with HR-QoL in children with OSA or sleep-related symptoms.

METHODS

Patients between ages 5 to 17 years who were referred to the sleep laboratory from June 2017 to August 2017 for overnight polysomnography were approached to participate in the study.

RESULTS

A total of 86 patients were included in the final analysis; 45 patients (52.3%) were male; and the median (interquartile range) of their mean BMI z-scores was 1.7 (0.5, 2.4). The patients were categorized by OSA severity as follows: 27 (31.4%) mild OSA, 11 (12.8%) moderate OSA, 24 (27.9%) severe OSA, and 24 (27.9%) without OSA. Severity of OSA was not correlated with any PROMIS domain. In univariable analyses, BMI z-score was negatively correlated with physical function mobility score (P = .002) and positively correlated with pain interference (P = .02) and pain intensity (P = .02). Total sleep time was positively correlated with physical function mobility (P = .03) and peer relationship (P = .002). Significant correlations between several PROMIS domains were also observed.

CONCLUSIONS

Total sleep time was associated with physical function mobility and peer relationship. Regression analysis demonstrated a relationship between BMI z-score, physical function mobility, and pain intensity in our study population.

COMMENTARY

A commentary on this article appears in this issue on page 541.