Longitudinal changes in bone density in adolescents and young adults with cerebral palsy: A case for early intervention

Zoledronate Increases Bone Mineral Density in Nonambulant Children With Cerebral Palsy: A Randomized Controlled Trial

CONTEXT

Zoledronate appears to reduce fracture rates in children with cerebral palsy (CP), but no previous randomized, controlled trial has been performed to compare the effect of zoledronate to placebo in children with CP.

OBJECTIVE

To investigate the effect of zoledronate on bone mineral density (BMD) Z-scores in children with nonambulant CP in a randomized, controlled, double-blind trial.

METHODS

Nonambulant children with CP (5 to 16 years of age) were randomized 1:1 to receive 2 doses of zoledronate or placebo at a 6-month interval. BMD Z-score changes at the lumbar spine and the lateral distal femur (LDF) were calculated from dual-energy x-ray absorptiometry scans. Monitoring included weight, bone age, pubertal staging, knee-heel length, adverse events, biochemical markers, and questionnaires.

RESULTS

Twenty-four participants were randomized and all completed the study. Fourteen were assigned to zoledronate. The mean lumbar spine BMD Z-score increased 0.8 SD (95% CI: 0.4; 1.2) in the zoledronate group, which was significant when compared to 0.0 SD (95% CI: -0.3; 0.3) in the placebo group. Similarly, the LDF BMD Z-scores increased more in the zoledronate group. Severe acute phase symptoms affected 50% of the patients in the zoledronate group but were reported exclusively after the first dose. Growth parameters were similar in both groups.

CONCLUSION

Zoledronate for 12 months increased BMD Z-scores significantly without affecting growth, but first-dose side effects were common and considerable. Studies into lower first doses and long-term outcomes are needed.

Epidemiology and demographics of pediatric proximal femur fractures in Türkiye: results from a government-based health registry

We evaluate the epidemiology and incidence of pediatric proximal femur fractures, treatment trends among different hospital levels, and complication rates among different treatment modalities by examining a national health registry in Türkiye. The health records of individuals aged ≤16 years admitted to public, private, and university hospitals were collected via the e-health database of the Turkish Ministry of Health. A total of 2388 children treated for proximal femur fractures from 2016 to 2021 with at least 2 years of follow-up were included in the study. While 2033 (85.1%) patients were treated with closed reduction and spica casts, 355 (14.8%) were operated on. Mean age was 8.603 ± 5.11 years. Male incidence was 2-fold greater compared to female patients (36.4% female and 63.6% male patients; P < 0.001). The frequency of cases was significantly increased in the age groups of 3-4 and 13-16 years. Comorbidities causing limited ambulation were detected in 6.5% of all cases, and 163 (8.0%) patients in the conservative group and 98 (27.6%) patients in the surgery group had at least one complication. The incidence was 0.45 per 100 000 children aged ≤16 years. This study reports the largest patient cohort to date, providing evidence on the epidemiology and incidence of pediatric proximal femur fractures using health registry data. We have found that the most common treatment modality for proximal femur fractures is closed reduction with spica casts. The rate of avascular necrosis is similar among patients treated surgically and those treated conservatively.

Lifelong Fitness in Ambulatory Children and Adolescents with Cerebral Palsy I: Key Ingredients for Bone and Muscle Health

Physical activity of a sufficient amount and intensity is essential to health and the prevention of a sedentary lifestyle in all children as they transition into adolescence and adulthood. While fostering a fit lifestyle in all children can be challenging, it may be even more so for those with cerebral palsy (CP). Evidence suggests that bone and muscle health can improve with targeted exercise programs for children with CP. Yet, it is not clear how musculoskeletal improvements are sustained into adulthood. In this perspective, we introduce key ingredients and guidelines to promote bone and muscle health in ambulatory children with CP (GMFCS I-III), which could lay the foundation for sustained fitness and musculoskeletal health as they transition from childhood to adolescence and adulthood. First, one must consider crucial characteristics of the skeletal and muscular systems as well as key factors to augment bone and muscle integrity. Second, to build a better foundation, we must consider critical time periods and essential ingredients for programming. Finally, to foster the sustainability of a fit lifestyle, we must encourage commitment and self-initiated action while ensuring the attainment of skill acquisition and function. Thus, the overall objective of this perspective paper is to guide exercise programming and community implementation to truly alter lifelong fitness in persons with CP.

Relationship of anthropometric measurements and percent body fat mass to cardiovascular disease risk factors in adults with cerebral palsy

INTRODUCTION

Adults with cerebral palsy (CP) face high morbidity from cardiovascular disease (CVD). Of concern, classic screening parameters are inconsistent in identifying CVD risk in this population. Dual-energy x-ray absorptiometry (DEXA), which provides direct measurements of fat mass (FM), may be an alternative screening method.

OBJECTIVE

To evaluate whether FM measurement with DEXA is feasible in screening adults with CP and compare FM and anthropometric measures to CVD risk factors.

DESIGN

Cross-sectional study.

SETTING

Outpatient rehabilitation hospital.

PARTICIPANTS

Forty-seven adults with CP.

MAIN OUTCOME MEASURES

Weight, height, waist circumference (WC), and hip circumference (HC) were measured; waist-to-hip ratio (WHR) and body mass index (BMI) were calculated. Blood pressure (BP), FM by DEXA, hemoglobin A1c (HbA1c), and lipid measurements were obtained. Logistic regression models investigated odds ratios (ORs) and 95% confidence intervals (CIs) between anthropometric measurements/FM and CVD risk factors; correlations were assessed using Pearson correlation coefficients.

RESULTS

Elevated BP or hypertension diagnosis was present in 47.8%; HbA1c ≥5.7% in 22.2%; and high-density lipoprotein (HDL) level below optimal for 33.3%. DEXA FM was obtained in 29 of 47 participants, as surgical metal and positioning limited many studies. Excess FM was noted in 75.9% versus 41.3% overweight/obese by BMI. WC correlated with HbA1c (r = 0.46, p = .002), HDL (r = -0.36, p = .018), and triglyceride (TG) levels (r = 0.30, p = .045); however at-risk WC values were associated only with odds of elevated HbA1c (OR 8.53, 95% CI 1.46-50.05; p = .018). HC correlated with HbA1c levels (r = 0.38, p = .011) and systolic BPs (r = 0.35, p = .019); similarly, ORs for elevated HC were weakly associated with elevated HbA1c and BPs (OR 1.08, 95% CI 1.01-1.16; p = .024 and OR 1.07, 95% CI 1.01-1.14; p = .024, respectively). WHR correlated with TGs; however few TG levels were elevated. FM measures were not associated with at-risk lab values or BPs.

CONCLUSIONS

DEXA FM measurements may not be feasible for CVD screening in many adults with CP. Although CVD risk factors are frequently present, anthropometric measurements commonly used for general population screening may not translate well to adults with CP.

Providing a Primary Care Medical Home for Children and Youth With Cerebral Palsy

Cerebral palsy (CP) is the most common motor disorder of childhood, with prevalence estimates ranging from 1.5 to 4 in 1000 live births. This clinical report seeks to provide primary care physicians with guidance to detect children with CP; collaborate with specialists in treating the patient; manage associated medical, developmental, and behavioral problems; and provide general medical care to their patients with CP.

Musculoskeletal Morbidity Among Adults Living With Spina Bifida and Cerebral Palsy

Background

Individuals living with cerebral palsy (CP) or spina bifida (SB) are at heightened risk for chronic health conditions that may develop or be influenced by the impairment and/or the process of aging.

Objectives

The objective of this study was to compare the incidence of and adjusted hazards for musculoskeletal (MSK) morbidities among adults living with and without CP or SB.

Methods

A retrospective, longitudinal cohort study was conducted among adults living with (n = 15,302) CP or SB and without (n = 1,935,480) CP or SB. Incidence estimates of common MSK morbidities were compared at 4 years of enrollment. Survival models were used to quantify unadjusted and adjusted hazard ratios for incident MSK morbidities. The analyses were performed in 2019 to 2020.

Results

Adults living with CP or SB had a higher 4-year incidence of any MSK morbidity (55.3% vs. 39.0%) as compared to adults without CP or SB, and differences were to a clinically meaningful extent. Fully adjusted survival models demonstrated that adults with CP or SB had a greater hazard for all MSK disorders; this ranged from hazard ratio (HR) 1.40 (95% CI, 1.33 to 1.48) for myalgia to HR 3.23 (95% CI, 3.09 to 3.38) for sarcopenia and weakness.

Conclusion

Adults with CP or SB have a significantly higher incidence of and risk for common MSK morbidities as compared to adults without CP or SB. Efforts are needed to facilitate the development of improved clinical screening algorithms and early interventions to reduce risk of MSK disease onset/progression in these higher risk populations.

Clinical bone health among adults with cerebral palsy: moving beyond assessing bone mineral density alone

AIM

To understand associations among bone mineral density (BMD), bone mineral content (BMC), and bone area, and their association with fractures in adults with cerebral palsy (CP).

METHOD

This retrospective cohort study included 78 adults with CP with a hip dual energy X-ray absorptiometry (DXA) from 1st December 2012 to 3rd May 2021 performed at the University of Michigan. Data-driven logistic regression techniques identified which, if any, DXA-derived bone traits (e.g. age/sex/ethnicity-based z-scores) were associated with fracture risk by sex and severity of CP. BMC-area associations were examined to study the structural mechanisms of fragility.

RESULTS

Femoral neck area was associated with lower age-adjusted odds ratios (ORs) of fracture history (OR 0.72; 95% confidence interval [CI] 0.49-1.06; p=0.098), while higher BMD was associated with higher odds of incident fracture (OR 3.08; 95% CI 1.14-8.33; p=0.027). Females with fracture had lower area than females without fracture but similar BMC, whereas males with fracture had larger area and higher BMC than males without fracture. The paradoxical BMD-fracture association may be due to artificially elevated BMD from BMC-area associations that differed between females and males (sex interaction, p˂0.05): males had higher BMC at lower area values and lower BMC at higher area values compared to females.

INTERPRETATION

BMD alone may not be adequate to evaluate bone strength for adults with CP. Further research into associations (or integration) between BMC and area is needed.

Secondary Osteoporosis

Osteoporosis is a global public health problem, with fractures contributing to significant morbidity and mortality. Although postmenopausal osteoporosis is most common, up to 30% of postmenopausal women, > 50% of premenopausal women, and between 50% and 80% of men have secondary osteoporosis. Exclusion of secondary causes is important, as treatment of such patients often commences by treating the underlying condition. These are varied but often neglected, ranging from endocrine to chronic inflammatory and genetic conditions. General screening is recommended for all patients with osteoporosis, with advanced investigations reserved for premenopausal women and men aged < 50 years, for older patients in whom classical risk factors for osteoporosis are absent, and for all patients with the lowest bone mass (Z-score ≤ -2). The response of secondary osteoporosis to conventional anti-osteoporosis therapy may be inadequate if the underlying condition is unrecognized and untreated. Bone densitometry, using dual-energy x-ray absorptiometry, may underestimate fracture risk in some chronic diseases, including glucocorticoid-induced osteoporosis, type 2 diabetes, and obesity, and may overestimate fracture risk in others (eg, Turner syndrome). FRAX and trabecular bone score may provide additional information regarding fracture risk in secondary osteoporosis, but their use is limited to adults aged ≥ 40 years and ≥ 50 years, respectively. In addition, FRAX requires adjustment in some chronic conditions, such as glucocorticoid use, type 2 diabetes, and HIV. In most conditions, evidence for antiresorptive or anabolic therapy is limited to increases in bone mass. Current osteoporosis management guidelines also neglect secondary osteoporosis and these existing evidence gaps are discussed.

Critical periods of bone health across the lifespan for individuals with cerebral palsy: Informing clinical guidelines for fracture prevention and monitoring

BACKGROUND

Skeletal fragility is a major burden for individuals with cerebral palsy (CP), but little is known clinically about when to prevent fractures or monitor bone health for this population. Critical periods of bone health (CPBH) are important windows for intervention to augment bone growth or mitigate bone loss. However, CPBH from the general population may not align with the needs or timing of skeletal fragility for individuals with CP. The objective of this study was to identify discrepancies when evaluating individuals with CP using CPBH across the lifespan from the general population, and propose new CP-specific CPBH.

METHODS

Data from 2016 administrative claims databases were used, including the Optum's De-identified Clinformatics® Data Mart Database and a random 20% sample of the Medicare fee-for-service database from the Centers for Medicare and Medicaid Services. Sex-stratified fracture prevalence was compared between individuals with and without CP across the lifespan starting at 2 years of age using age groups to capture important stages of development and 3-4-year age bands in adulthood (up to >80 years). Sex-specific CPBH from the general population included: rapid bone accrual, peak bone mass, menopause, and elderly.

RESULTS

There were 23,861 individuals with CP and 9,976,161 individuals without CP. CPBH from the general population did not align with the timing of skeletal fragility for CP. For example, fractures were rare and decreased throughout the CPBH of peak bone mass for males without CP, but males with CP had a greater relative fracture risk (2.9-5.6-fold higher) and a substantially increased rate of fracture (CP-slope 14× higher than non-CP-slope). For females with CP, fracture risk was increased by 18-21 years, with additional inflection points (e.g., decade before menopause and again by 57-60 years). For males with CP, fracture risk in mid-life exhibited a pattern similar to elderly males without CP.

CONCLUSIONS

This study identified discrepancies in evaluating fracture risk for individuals with CP if using established CPBH from the general population. We therefore propose new CP- and sex-specific CPBH for fracture monitoring and prevention.

Bisphosphonate use in children with cerebral palsy

BACKGROUND

Cerebral palsy (CP) is a heterogeneous group of non-progressive disorders of posture or movement, caused by a lesion of the developing brain. Osteoporosis is common in children with cerebral palsy, particularly in children with reduced gross motor function, and leads to an increased risk of fractures. Gross motor function in children with CP can be categorised using a tool called the Gross Motor Function Classification System (GMFCS). Bisphosphonate increases bone mineral density (BMD) and reduces fracture rates. Bisphosphonate is used widely in the treatment of adult osteoporosis. However, the use of bisphosphonate in children with CP remains controversial, due to a paucity of evidence and a lack of recent trials examining the efficacy and safety of bisphosphonate use in this population.

OBJECTIVES

To examine the efficacy and safety of bisphosphonate therapy in the treatment of low BMD or secondary osteoporosis (or both) in children with cerebral palsy (GMFCS Levels III to V) who are under 18 years of age.

SEARCH METHODS

In September 2020, we searched CENTRAL, MEDLINE, Embase, six other databases, and two trial registers for relevant studies. We also searched the reference lists of relevant systematic reviews, trials, and case studies identified by the search, and contacted the authors of relevant studies in an attempt to identify unpublished literature.

SELECTION CRITERIA

All relevant randomised controlled trials (RCTs), and quasi-RCTs, comparing at least one bisphosphonate (given at any dose, orally or intravenously) with placebo or no drug, for the treatment of low BMD or osteoporosis in children up to 18 years old, with cerebral palsy (GMFCS Levels III to V).

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We were unable to conduct any meta-analyses due to insufficient data, and therefore provide a narrative assessment of the results.

MAIN RESULTS

We found two relevant RCTs (34 participants). Both studies included participants with non-ambulatory CP or CP and osteoporosis. Participants in both studies were similar in severity of CP, age distribution, and sex distribution. The two trials used different bisphosphonate medications and different intervention durations, but further comparison of the interventions was not possible due to a lack of published data from one trial. One trial received funding and support from research, academic, and hospital foundations, with pharmaceutical companies providing components of the calcium and vitamin supplement; the other trial did not report sources of funding. We judged one study at an overall high risk of bias; the other as overall unclear risk of bias.

PRIMARY OUTCOME

Compared to placebo or no treatment, both studies provided very low certainty evidence of improved BMD at least four months post-intervention in children treated with bisphosphonate. Only one study (12 participants) provided sufficient detail to assess a measure of the effect, and reported an improvement at six months post-intervention in lumbar spine z-score (mean difference (MD) 18%, 95% confidence interval (CI) 6.57 to 29.43; very low certainty evidence).

SECONDARY OUTCOMES

Very low certainty evidence from one study found that bisphosphonate reduced serum N-telopeptides (NTX) more than placebo; the other study reported that both bisphosphonate plus alfacalcidol and alfacalcidol alone reduced NTX, but did not compare groups. One study reported inconclusive results between groups for serum bone-specific alkaline phosphatase (BAP). The other study reported that both bisphosphonate plus alfacalcidol and alfacalcidol alone reduced BAP, but did not compare groups. Neither study reported data for the effect of bisphosphonate treatment on changes in volumetric BMD in the distal radius or tibia, changes in fracture frequency, bone pain, or quality of life. One study reported that two participants had febrile events noted during their first dosing schedule, but no further adverse events were reported in either relevant study.

AUTHORS' CONCLUSIONS

Based on the available evidence, there is very low certainty evidence that bisphosphonate treatment may improve bone health in children with cerebral palsy. We could only include one study with 14 participants in the assessment of the effect size; therefore, the precision of the effect estimate is low. We could only evaluate one planned primary outcome, as there was insufficient detail reported in the relevant studies. Further research from RCTs on the effect and safety of bisphosphonate to improve bone health in children with cerebral palsy is required. These studies should clarify the optimal standard treatment regarding weight-bearing exercises, vitamin D and calcium supplementation, and should include fracture frequency as a primary outcome.

Bone Health in Childhood Chronic Disease

Many children with chronic disease are now surviving into adulthood. As a result, there is a growing interest in optimizing bone health early in the disease course with the dual goals of improving quality of life during childhood and reducing life-long fracture risk. Risk factors for impaired bone health in these children include immobility, nutritional deficiency, exposure to bone toxic therapies, hormonal deficiencies affecting growth and pubertal development, and chronic inflammation. This review focuses on the chronic diseases of childhood most commonly associated with impaired bone health. Recent research findings and clinical practice recommendations, when available, for specific disorders are summarized.

Effects of Neurological Disorders on Bone Health

Neurological diseases, particularly in the context of aging, have serious impacts on quality of life and can negatively affect bone health. The brain-bone axis is critically important for skeletal metabolism, sensory innervation, and endocrine cross-talk between these organs. This review discusses current evidence for the cellular and molecular mechanisms by which various neurological disease categories, including autoimmune, developmental, dementia-related, movement, neuromuscular, stroke, trauma, and psychological, impart changes in bone homeostasis and mass, as well as fracture risk. Likewise, how bone may affect neurological function is discussed. Gaining a better understanding of brain-bone interactions, particularly in patients with underlying neurological disorders, may lead to development of novel therapies and discovery of shared risk factors, as well as highlight the need for broad, whole-health clinical approaches toward treatment.