Boys with haemophilia have low trabecular bone mineral density and sarcopenia, but normal bone strength at the radius

Diagnostic criteria, prevalence, and clinical outcomes of pediatric sarcopenia: A scoping review

BACKGROUND & AIMS

Sarcopenia, characterized by loss of muscle mass and decreased muscle strength, significantly affects adults but also influences pediatric health. However, definitions for low muscle mass, decreased strength, and sarcopenia in children are less established, impacting interventions for improving health outcomes. The objective of this scoping review is synthesize the existing literature on the diagnostic criteria, prevalence and clinical outcomes of sarcopenia.

METHODS

A scoping review, following the PRISMA extension for scoping reviews, examined pediatric sarcopenia literature until June 2023. The literature search was performed using MEDLINE and the Cochrane Central Register of Controlled Trials with the last search conducted on June 30, 2023. Criteria included studies on aged 0-20 years, covering healthy subjects, acutely ill patients, and chronic disease cases excluding specific conditions like neuromuscular diseases or prematurity.

RESULTS

Initial search found 503 studies, finally, we included 56 studies. Most studies diagnosed sarcopenia using skeletal muscle mass indicators like total psoas muscle area from Computed Tomography or Magnetic Resonance Imaging. Around half of the longitudinal studies highlighted sarcopenia as a risk factor for various clinical outcomes, predominantly in hospitalized patients. However, cutoff values for sarcopenia indicators lacked consistency, with studies employing diverse percentile-based measurements or z-scores.

CONCLUSION

Pediatric sarcopenia diagnosis primarily relies on skeletal muscle mass, with identified links to future clinical outcomes in specific conditions. The lack of standardized cutoffs for sarcopenia indicators underscores the necessity for age, gender, and race-specific cutoff values derived from studies establishing reference values for muscle mass and strength across diverse pediatric populations.

The frequency of sarcopenia in haemophilia patients: Effects on musculoskeletal health and functional performance

INTRODUCTION

In patients with haemophilia A, chronic arthropathy develops over time as a result of recurrent joint bleeds, which leads to restricted mobility and disability in the affected joints. There are limited studies in the literature evaluating sarcopenia in patients with haemophilia. The present study aims to determine the prevalence of sarcopenia in severe haemophilia-A patients and to evaluate musculoskeletal health and functional performance.

METHODS

Thirty haemophilia-A patients and 26 adult male volunteers were enrolled in the study. For detection of sarcopenia, the appendicular skeletal muscle mass (ASM) obtained by bioelectrical impedance analysis (BIA) was divided by height squared (m2 ) to obtain the appendicular skeletal muscle mass index (ASMI) value. The thighs of both lower extremities were measured using the Modified Sonographic Tight Adjustment Ratio (STAR) method, which was obtained by adding the bilateral rectus femoris and vastus intermedius muscle thicknesses measured by ultrasound. Hand and quadriceps muscle strength (MS) were measured with a dynamometer. Physical performance was determined using the walking speed (WS), timed up-and-go test (TUGT), 5-repetition sit-to-stand test (5RSTS), and 6-min walk test (6MWT). Haemophilia Joint Health Score (HJHS) and Haemophilia Early Arthropathy Detection-Ultrasonography (HEAD-US) were also used to assess the musculoskeletal system.

RESULTS

According to the modified STAR values calculated based on body mass index, sarcopenia was present in 15 (50%) of 30 patients. However, based on the ASMI-BIA values, sarcopenia was present in only two (6.6%) patients. A weak correlation was found between ASMI and HJHS, HEAD-US, WS, TUGT, and hand MS (left), while a moderate correlation was found with knee MS (right), knee MS (left), and 5RSTS. A strong correlation was found between the modified STAR score and HEAD-US, HJHS, knee MS (left), 5RSTS, TUGT, and WS, while a moderate correlation was found with hand MS (left), hand MS (right), and knee MS (right).

CONCLUSION

This study showed muscle loss, joint mobility restrictions, and decreased functional capacity in haemophilia patients and demonstrated the presence of sarcopenia in these patients. The STAR measurement method showed stronger relationships with MS and functional performance values than ASMI measurements in terms of evaluating sarcopenia.

Association of bone mineral density and potential risk factors for osteoporosis in patients with severe haemophilia A

INTRODUCTION

In people with haemophilia (PWH), recurrent episodes of bleeding lead to joint deterioration and bone resorption. To date, the effects of various other factors on bone mineral density (BMD) reduction have found conflicting results.

AIM

The aim of this study was to analyse the relationships between BMD, bone mineral content (BMC), and trabecular bone score (TBS) parameters based on the dual X-ray absorptiometry method (DXA) and potential risk factors for osteoporosis in patients with severe haemophilia A.

METHODS

Fifty-five men with severe haemophilia A, aged 18-68 years, and 59 healthy volunteer men were enrolled in this study. Densitometric-derived lumbar spine and femoral neck BMD, BMC, and TBS were measured. Blood analyses were performed for morphology parameters, liver and kidney function parameters, and viral status. Serum levels of oestradiol (E2 ), testosterone (T), dehydroepiandrosterone sulphate (DHEA-S), parathormone, and vitamin D were measured.

RESULTS

Patients showed significantly lower BMD compared to controls (p < .003). The result below the expected range for age was nearly double (6.82% vs. 3.92%) in PWH under 50 years old compared to controls. Haemophilic patients also exhibited significantly higher vitamin D3 deficiency (p < .0001), which was strongly associated with low TBS. Additionally, low body mass index and high neutrophil/lymphocyte ratio were correlated with low BMC and BMD.

CONCLUSIONS

This study confirms the prevalence of low BMD and BMC in patients with haemophilia in Poland. Factors that contribute to low BMD are primarily vitamin D deficiency, low BMI, high neutrophil/lymphocyte ratio, and low testosterone/oestradiol ratio.

Diminished cortical bone density of long bones among children with haemophilic arthropathy

INTRODUCTION

Children with haemophilia (CwH) have lower bone mineral density in the spine (trabecular bone) than healthy children. There are few studies focusing on bone mineral density in long bones (cortical bone).

AIM

To evaluate bi-laterally the distal third of radius and midshaft tibias using quantitative ultrasound (QUS) and assess the speed of sound (SoS).

METHODS

A cross-sectional study where 91 CwH and 91 age-matched healthy boys were included. Joint evaluation was determined with the Haemophilia Joint Health Score 2.1 and SoS values. The Z scores were measured with the Sunlight Omnisense 8000 S equipment.

RESULTS

Ninety-one CwH (haemophilia A) were evaluated (26 mild form, 26 moderate, and 39 severe). Most patients were treated with on-demand factor replacement and had higher total HJHS scores according to severity (4.8, 14.8 and 14.1, respectively). Patients with moderate and severe disease showed a statistical difference in SoS values for both radius and tibias compared to controls. QUS Z-scores ≥-2 were more frequent in radius and tibias in CwH, but were statistically significant only in tibias when compared to controls (in 30% mild, 46% moderate, 28% severe, respectively).

CONCLUSIONS

There was diminished cortical bone density in radius and tibias of CwH compared to healthy controls. Changes predominated in tibias, more frequently affected according to the severity of haemophilia. Early intervention with factor replacement combined with physical activity are key aspects to promote bone health.

Uncoupling of Bone Turnover may Compromise Skeletal Health of Young Patients With Haemophilia A

There is evidence that bone mass is decreased and bone metabolism is dysregulated in children with haemophilia (CWH). The objective of this study was to investigate the impact of haemophilia on skeletal health in children, with regards to bone mineral density (BMD) and metabolic bone profile. This study included 51 male CWH A. Dual-energy X-ray absorptiometry (DXA) was performed to assess BMD in lumbar spine (LS) and total body less head (TBLH) and Z-scores were calculated (low BMD Z-score<-2, low-normal BMD Z-score between -1 and -2). Serum levels of osteocalcin (OC), procollagen type I C-terminal propeptide (PICP), bone alkaline phosphatase (bALP), bone tartrate-resistant acid phosphatase 5b (TRAP5b), vitamin D, parathormone (PTH), urinary calcium/creatinine (uCa/uCr) and urine deoxypyridinoline/creatinine (uDPD/uCr) were measured. Mean BMD Z-scores were lower than predicted at both sites of measurement. More specifically, 10% of CWH A had low and 20% low-normal BMD Z-scores in LS, whereas 9.1% had low-normal TBLH BMD Z-scores and there were no patients with low BMD Z-scores at this site of measurement. 36.7% of CWH had low vitamin D levels and 19.6% had a history of fracture. Also, patients with haemophilia had lower OC and higher uDPD/uCr levels while OC positively correlated to BMD Z-scores and uDPD/uCr negatively correlated to BMD Z-scores at both sites. No statistically significant differences were observed with regards to mode of treatment, number of haemorrhages and the presence of target-joints. CWH A had decreased BMD Z-scores at both sites with an uncoupling of bone turnover LS BMD seemed to be more affected than TBLH BMD.

FVIII at the crossroad of coagulation, bone and immune biology: Emerging evidence of biological activities beyond hemostasis

Hemophilia A is an X-linked hereditary disorder that results from deficient coagulation factor VIII (FVIII) activity, leading to spontaneous bleeding episodes, particularly in joints and muscles. FVIII deficiency has been associated with altered bone remodeling, dysregulated macrophage polarization, and inflammatory processes that are associated with the neoformation of abnormal blood vessels. Treatment based on FVIII replacement can lead to the development of inhibitors that render FVIII concentrate infusion ineffective. In this context, hemophilia has entered a new therapeutic era with the development of new drugs, such as emicizumab, that seek to restore the hemostatic balance by bypassing pathologically acquired antibodies. We discuss the potential extrahemostatic functions of FVIII that may be crucial for defining future therapies in hemophilia.

Low bone mass and hypovitaminosis D in haemophilia: A single-centre study in patients with severe and moderate haemophilia A and B

INTRODUCTION

Haemophilia (H) is frequently associated with a multifactorial reduction in bone mineral density (BDM), but little is known about possible differences between HA and HB according to their severity.

AIM

To evaluate the association between low bone mineral density (BMD), 25-hydroxyvitamin D [25(OH)D] concentrations and bone turnover markers in patients with HA and HB younger or older than 50 years.

METHODS

In 78 patients <50 years and 33 patients >50 years with severe (S) or moderate (M) HA and HB, BMD was measured by dual-energy X-ray absorptiometry at femoral neck (FN) and lumbar spine and then correlated to annual bleeding rate (ABR), World Federation of Haemophilia orthopaedic joint scale (WFH score), 25(OH)D concentrations, parathyroid hormone (PTH), amino-terminal telopeptide of type 1 collagen (NTx), urinary pyridinolines, osteocalcin and bone-specific alkaline phosphatase.

RESULTS

Overall, a high prevalence of hypovitaminosis D was diagnosed. In patients <50 years, low FN-BMD was significantly more frequent in HA than in HB, while PTH, pyridinolines, ABR and WFH score were associated with H type and severity. In patients >50 years, similarly low FN-BMD was observed in HA and HB, while ABR and WFH score were associated with H type and severity, being milder in HB.

CONCLUSIONS

Low bone mass is a frequent comorbidity in haemophilic patients of all ages, apart from those with MHB. Clinical and laboratory assessments confirm a higher bone impairment and faster bone resorption in HA compared with HB. Looking at H type and severity, MHB seems to have a normal bone metabolism and a less severe disease.

Obesity in the global haemophilia population: prevalence, implications and expert opinions for weight management

Overweight and obesity may carry a significant disease burden for patients with haemophilia (PWH), who experience reduced mobility due to joint inflammation, muscle dysfunction and haemophilic arthropathy. This review aimed to define the prevalence and clinical impact of overweight/obesity in the global population of PWH. A detailed literature search pertaining to overweight/obesity in haemophilia in the last 15 years (2003-2018) was conducted, followed by a meta-analysis of epidemiological data. The estimated pooled prevalence of overweight/obesity in European and North American PWH was 31%. Excess weight in PWH is associated with a decreased range in motion of joints, accelerated loss of joint mobility and increase in chronic pain. Additionally, the cumulative disease burden of obesity and haemophilia may impact the requirement for joint surgery, occurrence of perioperative complications and the prevalence of anxiety and depression that associates with chronic illness. Best practice guidelines for obesity prevention and weight management, based on multidisciplinary expert perspectives, are considered for adult and paediatric PWH. Recommendations in the haemophilia context emphasize the importance of patient education and tailoring engagement in physical activity to avoid the risk of traumatic bleeding.

Impact of target joint and FVIII inhibitor οn bone properties in children with haemophilia A: A peripheral quantitative computed tomography study

BACKGROUND

Haemophilic children are prone to low bone mass accrual.

OBJECTIVE

To assess bone properties in haemophilic children, using peripheral quantitative computed tomography (pQCT) and to correlate findings with clinical data.

SUBJECTS/METHODS

Peripheral quantitative computed tomography scan of both radii and tibiae were performed in 31 haemophilic A children (severe 24, mean age 11.2 years). Seven subjects had a history of inhibitors. Five children had an upper extremity target-joint and 12 had at least one lower extremity target-joint. The following parameters were measured: trabecular, total and cortical bone density and content (TBD, ToBD, CBD, TbC, CC), strength-stress index (SSI), and tibial cross-sectional area (CA), outer and inner bone contour length (PERI, ENDO) and cortical thickness (CTHC).

RESULTS

Mean right radius TBD was significantly higher than the left one (P = 0.015). In subjects with arm target-joint, radius TBD was significantly lower in the target than in non-target arm (186.6 ± 60.4 vs 218.6 ± 39.8, P = 0.032). Left arm target-joint subjects had significantly lower left radius TBD in comparison to subjects without arm target-joint (155.4 ± 50.3 vs 215.7 ± 37.9, P = 0.019). There were no similar differences in leg target-joint. Bone quality and geometry parameters in cortical compartment were significantly lesser in inhibitor group, with statistically significant side-to-side differences for legs and arms and left side predominance.

CONCLUSION

In children with haemophilia A and a history of target-joint and/or FVIII inhibitor, abnormalities may occur in the long bones as were revealed by pQCT, where low trabecular density and weak cortical bone quality in upper and lower extremities, respectively, were confirmed.

Vitamin D deficiency and osteoporosis in hemophilic children: an intermingled comorbidity

The aim of this study is to investigate bone state and factors affecting it in children with hemophilia. This is a case-control study that included 37 children with hemophilia and 37 healthy controls. The patients were selected from the outpatient pediatric hematology clinic of Fayoum University Hospital, Egypt. Bone mineral density, serum vitamin D, parathormone, calcium, phosphorus, and calcium creatinine ratio levels were evaluated. Vitamin D level and bone mineral density were significantly lower in hemophiliacs than in control group (P < 0.0001). About 43.2% of cases had moderate vitamin D deficiency, whereas 35.1% had mild deficiency. Vitamin D positively correlated with bone mineral density Z-score, whereas it negatively correlated with total joint score. Positive correlation between bone mineral density and age was also found. Serum levels of urea, urinary calcium creatinine ratio, and parathormone were found to be higher in cases than in control. Also, serum calcium level was found to be lower in patients than in controls. We concluded that vitamin D deficiency is an essential cause of decreased bone mineral density in hemophilic children. Hemophilic arthropathy with consecutive immobilization plays an important role in vitamin D deficiency and decreased bone mineral density.

Abnormal joint and bone wound healing in hemophilia mice is improved by extending factor IX activity after hemarthrosis

Wound healing requires interactions between coagulation, inflammation, angiogenesis, cellular migration, and proliferation. Healing in dermal wounds of hemophilia B mice is delayed when compared with hemostatically normal wild-type (WT) mice, with abnormal persistence of iron deposition, inflammation, and neovascularity. We observed healing following induced joint hemorrhage in WT and factor IX (FIX) knockout (FIX^-/-) mice, examining also parameters previously studied in an excisional skin wound model. Hemostatically normal mice tolerated this joint bleeding challenge, cleared blood from the joint, and healed with minimal pathology, even if additional autologous blood was injected intra-articularly at the time of wounding. Following hemarthrosis, joint wound healing in hemophilia B mice was impaired and demonstrated similar abnormal histologic features as previously described in hemophilic dermal wounds. Therefore, studies of pathophysiology and therapy of hemophilic joint bleeding performed in hemostatically normal animals are not likely to accurately reflect the healing defect of hemophilia. We additionally explored the hypothesis that the use of a FIX replacement protein with extended circulating FIX activity could improve synovial and osteochondral wound healing in hemophilic mice, when compared with treatment with unmodified recombinant FIX (rFIX) in the established joint bleeding model. Significantly improved synovial wound healing and preservation of normal osteochondral architecture are achieved by extending FIX activity after hemarthrosis using glycoPEGylated FIX when compared with an equivalent dose of rFIX. These results suggest that treating joint bleeding only until hemostasis is achieved may not result in optimal joint healing, which is improved by extending factor activity.

Peripheral quantitative computed tomography (pQCT) for the assessment of bone strength in most of bone affecting conditions in developmental age: a review

Peripheral quantitative computed tomography provides an automatical scan analysis of trabecular and cortical bone compartments, calculating not only their bone mineral density (BMD), but also bone geometrical parameters, such as marrow and cortical Cross-Sectional Area (CSA), Cortical Thickness (CoTh), both periosteal and endosteal circumference, as well as biomechanical parameters like Cross-Sectional Moment of Inertia (CSMI), a measure of bending, polar moment of inertia, indicating bone strength in torsion, and Strength Strain Index (SSI). Also CSA of muscle and fat can be extracted. Muscles, which are thought to stimulate bones to adapt their geometry and mineral content, are determinant to preserve or increase bone strength; thus, pQCT provides an evaluation of the functional 'muscle-bone unit', defined as BMC/muscle CSA ratio. This functional approach to bone densitometry can establish if bone strength is normally adapted to the muscle force, and if muscle force is adequate for body size, providing more detailed insights to targeted strategies for the prevention and treatment of bone fragility. The present paper offers an extensive review of technical features of pQCT and its possible clinical application in the diagnostic of bone status as well as in the monitoring of the skeleton's health follow-up.

Haemophilia A and B as a cause for secondary osteoporosis and increased fracture risk

Despite the increasing evidence regarding its association with low bone mineral density (BMD) both in adults and children, haemophilia A or B has not yet been considered among the classic causes of secondary osteoporosis. Although the exact mechanisms are not fully elucidated, physical inactivity and vitamin D deficiency seem to play a fundamental role for such an association. Viral infections and arthropathy further compromise bone mass. Except for low BMD, patients with haemophilia seem to be at increased risk for fracture and falls. The FRAX tool may be of value in this population, for the estimation of fracture risk. Regular exercise, prophylactic factor replacement therapy in severe haemophilia, fall prevention strategies and optimization of calcium and vitamin D intake are recommended. In any case, individualized multidisciplinary approach and careful assessment and management of fracture risk are recommended.

Premature changes in trabecular and cortical microarchitecture result in decreased bone strength in hemophilia

Low bone density is a growing concern in aging men with hemophilia and may result in high-morbidity fragility fractures. Using high-resolution peripheral quantitative computed tomography (HR-pQCT), we demonstrate low trabecular and cortical bone density contributing to lower volumetric bone mineral density (BMD) at both distal radius and tibia in patients with hemophilia compared with age- and sex-matched controls. The low trabecular bone density found in hemophilia is attributed to significantly decreased trabecular number and increased separation; the lower cortical bone density results from thinner cortices, whereas cortical porosity is maintained. Microfinite element analysis from three-dimensional HR-pQCT images demonstrates that these microarchitectural deficits seen in patients with hemophilia translate into significantly lower estimated failure load (biomechanical bone strength) at the distal tibia and radius when compared with controls. In addition, an inverse association of joint score with BMD and failure load suggests the negative role of hemophilic arthropathy in bone density loss.

Quantitative computer tomography in children and adolescents: the 2013 ISCD Pediatric Official Positions

In 2007, International Society of Clinical Densitometry Pediatric Positions Task Forces reviewed the evidence for the clinical application of peripheral quantitative computed tomography (pQCT) in children and adolescents. At that time, numerous limitations regarding the clinical application of pQCT were identified, although its use as a research modality for investigation of bone strength was highlighted. The present report provides an updated review of evidence for the clinical application of pQCT, as well as additional reviews of whole body QCT scans of the central and peripheral skeletons, and high-resolution pQCT in children. Although these techniques remain in the domain of research, this report summarizes the recent literature and evidence of the clinical applicability and offers general recommendations regarding the use of these modalities in pediatric bone health assessment.

Peripheral quantitative computed tomography (pQCT) reveals alterations in the three-dimensional bone structure in children with haemophilia

Children with haemophilia are at risk of suboptimal bone mass accrual and low bone mineral density (BMD). We recently demonstrated that although BMD in Finnish children with haemophilia was within the normal range, their whole body BMD was significantly lower and hypercalciuria more prevalent than in controls. This study sought to determine the bone structure and strength in physically active children with haemophilia. To investigate the underlying mechanisms in this group, we conducted a case-control study to assess bone structure and strength by peripheral quantitative computed tomography (pQCT) at the radius. The study group comprised 29 patients (mean age 12.2 years) and 46 age-matched controls. Children with haemophilia had decreased total BMD Z-score at the distal radius (P ≤ 0.001), but increased cortical bone density at the proximal radius (P ≤ 0.001). Total bone area at the proximal radius was significantly lower in children with haemophilia (P = 0.002), whereas there were no differences in cortical bone area or in polar Strength-Strain Index, a parameter of bone strength, between the patients and controls. Patients with mild to moderate haemophilia and on-demand treatment had inferior bone strength compared to those with moderate to severe haemophilia and prophylaxis. Our findings suggest altered skeletal development in patients with haemophilia in the radius, resulting in smaller bone size and higher cortical bone density. Importantly, bone strength at the radius appears equal to healthy children. Prophylactic treatment seems to have a beneficial effect on bone health.