Physical Impairment and Function in Children and Adolescents With Sickle Cell Disease: A Systematic Review

The Burden of Sickle Cell Disease on Children and Their Caregivers: Caregiver Reports of Children's Health-Related Quality of Life and School Experiences, Caregiver Burden, and Their Association with Frequency of Vaso-Occlusive Crises

Background

Children with sickle cell disease (SCD) experience a multiplex of disease-related symptoms and complications, including vaso-occlusive crises (VOCs), episodes characterized by extreme pain.

Methods

A cross-sectional observational survey examined the health-related quality of life (HRQoL) and school experiences of children with SCD 2 months-11 years, burden experienced by their caregivers, and associations between these outcomes and VOC frequency. Caregivers (N=167) of children with SCD in the US completed the Infant-Toddler Quality of Life-Short Form 47 (ITQoL-SF47) for children 2 months-4 years, the Child Health Questionnaire-Parent Form 50 (CHQ-PF50) and PROMIS Pain Interference and Sleep Disturbance Parent Proxy short forms for children 5-11 years, and a study-specific survey of school experiences.

Results

Children with SCD 2 months-4 years had lower ITQoL-SF47 scores (ie, worse HRQoL, p<0.001) than a normative sample of children; across domains, differences ranged from 18.73-45.03 points and exceeded minimal important difference (MID) thresholds. Except for the behavior domain, children with SCD 5-11 years had lower scores on all CHQ-PF50 domains than the normative sample (p<0.001); differences ranged from 6.78-36.37 points and exceeded MID thresholds. Children with more frequent VOCs had lower HRQoL and worse school experiences than children with less frequent VOCs (p<0.05, except for behavior domains). The largest differences based on VOC frequency were observed for overall health and bodily pain/discomfort among children 2 months-4 years (differences=40.88 and 32.50 points, respectively), and bodily pain and role/social limitations due to physical health among children 5-11 years (differences=38.99 and 37.80, respectively). Caregivers of children with more frequent VOCs experienced greater burden than caregivers of children with less frequent VOCs, though specific areas of impact (eg, caregiver emotions, time) differed across child age groups.

Conclusion

VOC frequency is negatively associated with HRQoL, highlighting the burden experienced by children with SCD and their caregivers.

Muscle Properties, Gross Motor Performance, and Quality of Life in Children With Sickle Cell Disease

PURPOSE

To explore muscle properties, gross motor performance, and quality of life (QoL) in children with sickle cell disease (SCD) compared with controls and to assess relationships among these outcomes.

METHODS

A cross-sectional study of 24 children assessed muscle properties including: knee extension strength by dynamometry; vastus lateralis (VL) and rectus femoris (RF) muscle thickness by ultrasonography; and VL and RF neuromuscular activation (rate of muscle activation [RoA]) by electromyography (EMG). Gross motor performance and QoL were assessed by standardized tests and questionnaires.

RESULTS

Children with SCD had impaired knee extension strength, VL EMG RoA, gross motor performance, and QoL compared with children without SCD. Relationships among muscle properties, gross motor performance, and QoL were identified.

CONCLUSIONS

These findings indicate that comprehensive muscle properties, gross motor performance, and QoL assessments should be considered to support and develop individualized physical therapy plans for children with SCD.

Diaphragm excursion correlates with performance and ventilation on the 6-min walk test in children with sickle cell disease

INTRODUCTION

Diaphragm function may be impaired in children with sickle cell disease (SCD). We hypothesized that diaphragm function is related to performance and ventilation on the 6-min walk test (6MWT).

METHODS

Respiratory muscle testing, diaphragm ultrasonography, and the 6MWT with portable gas analysis were performed on children with SCD and age- and sex-matched controls.

RESULTS

Fourteen children with SCD were enrolled. Comparisons were made between nine children with SCD (9.89  ± $\pm $  2.93 years) and nine controls (10.33  ± $\pm $  2.35 years). Diaphragm thickness at total lung capacity, thickening fraction, and excursion time during quiet breaths and deep breaths (DB), all normalized by forced vital capacity, were greater in children with SCD ( p < $p\lt $ 0.05 for all). 6MWT distance was shorter in children with SCD (450.87  ± $\pm $  74.2 m vs. 579.22 ± $\pm $ 72.46 m, p = $p=$ 0.01). Tidal volume ( V T ${V}_{T}$ ), minute ventilation ( V ˙ E ${\dot{V}}_{E}$ ), and oxygen consumption ( V ˙ O 2 ${\dot{V}}_{{O}_{2}}$ ) were also lower ( p < $p\lt $ 0.05 for all). DB excursion correlated positively with 6MWT distance ( r = $r=$ 0.648, p = $p=$ 0.023) and negatively with rate of perceived exertion (RPE) ( r = $r=$ -0.759, p = $p=$ 0.003). RPE correlated negatively with distance ( r = $r=$ -0.680, p = $p=$ 0.015). DB excursion time correlated positively with distance ( r = $r=$ 0.611, p = $p=$ 0.035), V T ${V}_{T}$ ( r = $r=$ 0.770, p = $p=$ 0.009), V ˙ E ${\dot{V}}_{E}$ ( r = $r=$ 0.736, p = $p=$ 0.015), and V ˙ O 2 ${\dot{V}}_{{O}_{2}}$ ( r = $r=$ 0.751, p = $p=$ 0.012).

CONCLUSIONS

Increased diaphragm excursion may be a strategy used to relieve air hunger while longer excursion time may reflect compensations to increase lung recruitment. Further studies are needed to better understand how these mechanisms affect exercise tolerance in children with SCD.

Skeletal Muscle Measurements in Pediatric Hematology and Oncology: Essential Components to a Comprehensive Assessment

Children with hematologic and oncologic health conditions are at risk of impaired skeletal muscle strength, size, and neuromuscular activation that may limit gross motor performance. A comprehensive assessment of neuromuscular function of these children is essential to identify the trajectory of changes in skeletal muscle and to prescribe therapeutic exercise and monitor its impact. Therefore, this review aims to (a) define fundamental properties of skeletal muscle; (b) highlight methods to quantify muscle strength, size, and neuromuscular activation; (c) describe mechanisms that contribute to muscle strength and gross motor performance in children; (d) recommend clinical assessment measures; and (e) illustrate comprehensive muscle assessment in children using examples of sickle cell disease and musculoskeletal sarcoma.