Compromised peak bone mass in patients with inflammatory bowel disease--a prospective study

Bone health screening practices with dual-energy X-ray absorptiometry and prediction of abnormal results in pediatric inflammatory bowel disease

OBJECTIVES

Pediatric patients diagnosed with inflammatory bowel disease (IBD) are at risk of suboptimal peak bone mass attainment. This study aimed to understand rates of bone health screening adherence, describe factors associated with dual-energy X-ray absorptiometry (DXA) acquisition, and identify factors associated with abnormal DXA.

METHODS

We performed a retrospective cohort study of pediatric IBD patients over a 10-year time frame. We included IBD patients (2-20 years of age) enrolled in ImproveCareNow and excluded patients with primary metabolic bone disease. Time-to-event methods and multivariable logistic regression were employed to identify factors associated with DXA acquisition and abnormal DXA.

RESULTS

In 676 patients, 464 (68.63%) pediatric patients with IBD had a risk factor for low bone mineral density (BMD); 137 (29.53%) underwent an initial DXA scan. Quiescent disease was significantly associated with a reduced likelihood of DXA (hazard ratio [HR]: 0.48; 95% confidence interval [CI]: 0.24-0.97), while weight z-score <-2 was significantly associated with DXA performance (HR: 2.07; 95% CI: 1.08-3.98). Abnormal DXA results (BMD z-score ≤-1) occurred in 59 (35.54%) individuals. After adjusting for visit diagnosis, delayed puberty, severe disease course, 6 months or greater of steroid exposure, and history of fracture, BMI z-score <-1 (odds ratio: 5.45; 95% CI: 2.41-12.33) was associated with abnormal DXA.

CONCLUSIONS

DXA screening occurred in less than one-third of eligible pediatric IBD patients. Compliance was more common in patients with a weight z-score <-2 and less common in those with quiescent disease. BMI strongly predicted abnormal DXA results when adjusting for risk factors for abnormal BMD.

Bone health in inflammatory bowel disease

INTRODUCTION

Inflammatory bowel disease (IBD) is a chronic disease characterized by the presence of systemic inflammation, manifesting not only as gastrointestinal symptoms but also as extraintestinal bone complications, including osteopenia and osteoporosis. However, the association between IBD and osteoporosis is complex, and the presence of multifactorial participants in the development of osteoporosis is increasingly recognized. Unlike in adults, delayed puberty and growth hormone/insulin-like growth factor-1 axis abnormalities are essential risk factors for osteoporosis in pediatric patients with IBD.

AREAS COVERED

This article reviews the potential pathophysiological mechanisms contributing to osteoporosis in adult and pediatric patients with IBD and provides evidence for effective prevention and treatment, focusing on pediatric patients with IBD. A search was performed from PubMed and Web of Science inception to February 2023 to identify articles on IBD, osteoporosis, pediatric, and fracture risk.

EXPERT OPINION

A comprehensive treatment pattern based on individualized principles can be used to manage pediatric IBD-related osteoporosis.

Low bone mineral density is associated with fatty liver disease and respiratory illness in a pediatric mortality sample

This study finds that fatty liver disease is associated with low bone density in a pediatric mortality sample. Since non-alcoholic fatty liver disease has increased in prevalence over the past few decades among children, a better understanding of the disease's impacts on bone health is of significance to clinicians.

PURPOSE

Chronic illness leads to decreased bone modeling and remodeling. This can be especially problematic during childhood and adolescence, since the majority of an individual's peak bone mass is achieved by the age of 20. In this study, we examine relationships between chronic illness and low bone mineral density (BMD) in a pediatric mortality sample (aged 0.5 to 20.9 years) from New Mexico. We also test whether low BMD is related to decelerated linear growth by examining its relationship to growth stunting and arrest (Harris lines).

METHODS

Hounsfield units (HU), a proxy for trabecular BMD, were obtained at the fourth lumbar vertebra and the femoral neck from postmortem CT scans. Linear regression was used to examine associations between z-standardized HU and age, sex, medical conditions, Harris lines, and growth stunting.

RESULTS

We find that lumbar HU is significantly lower for individuals with fatty liver disease and respiratory illness; femoral HU is significantly lower in individuals with Harris lines.

CONCLUSION

The mechanisms of low BMD in individuals with fatty liver disease and respiratory illness are likely multifactorial and involve vitamin D deficiency (malnutrition, malabsorption), systemic inflammation, and sedentary lifestyles. However, better awareness of this relationship can provide clinicians with the ability to introduce nutritional and behavioral interventions early to mitigate deleterious effects on bone. Harris lines, on the other hand, mark temporary growth cessation due to physiological stress followed by a rapid resumption of growth. Low BMD in these individuals may be due to bone mineralization lagging behind relatively rapid linear growth.

Vertebral Compression Fractures in Very Early Onset Inflammatory Bowel Disease

To describe clinical characteristics and outcomes of 3 patients with very early onset inflammatory bowel disease (VEOIBD) and vertebral compression fractures.

Methods

Patients with VEOIBD receiving care at a single tertiary center were prospectively enrolled in a longitudinal data repository. Retrospective chart review was performed to identify clinical characteristics and comorbidities. Those with clinically apparent vertebral compression fractures subsequently underwent an additional chart review focused on bone health.

Results

Three out of 216 (1.4%) patients with VEOIBD had symptomatic vertebral compression fractures. Of the 3 patients with vertebral compression fractures, all had Crohn's disease, 2 had monogenic inflammatory bowel disease, and all reported back pain. One patient notably had a normal dual-energy X-ray absorptiometry, highlighting a potential limitation of dual-energy X-ray absorptiometry to identify increased skeletal fragility in this population. Risk factors for suboptimal bone health included chronic inflammation secondary to poorly controlled inflammatory bowel disease, substantial glucocorticoid exposure, chronic use of other medications associated with suboptimal bone health including proton pump inhibitors and granulocyte colony-stimulating factor, and solid organ transplant. Patients treated with bisphosphonates had improved clinical outcomes, with resolution of back pain and increased bone mineral density.

Conclusions

Vertebral compression fracture should be considered in the differential diagnosis of patients with VEOIBD and back pain, especially in those with other risk factors for suboptimal bone health. Treatment of compression fractures with bisphosphonates resulted in resolution of back pain and improved bone density.

Management and monitoring of pediatric inflammatory bowel disease in the Asia-Pacific region: A position paper by the Asian Pan-Pacific Society for Pediatric Gastroenterology, Hepatology, and Nutrition (APPSPGHAN) PIBD Working Group: Surgical management, disease monitoring, and special considerations

Disease phenotype of pediatric inflammatory bowel disease (PIBD) in children from the Asia-Pacific region differs from that of children from the West. Many parts of Asia are endemic for tuberculosis, making diagnosis and management of pediatric Crohn's disease a challenge. Current available guidelines, mainly from Europe and North America, may not be completely applicable to clinicians caring for children with PIBD in Asia due to differences in disease characteristics and regional resource constraints. This position paper is an initiative from the Asian Pan-Pacific Society for Pediatric Gastroenterology, Hepatology and Nutrition (APPSPGHAN) that aims to provide an up-to-date, evidence-based approach to PIBD in the Asia-Pacific region. A group of pediatric gastroenterologists with a special interest in PIBD performed an extensive literature search covering epidemiology, disease characteristics and natural history, management, and monitoring. Attention was paid to publications from the region with special consideration to a resource-limited setting. This current position paper deals with surgical management, disease monitoring, immunization, bone health, and nutritional issues of PIBD in Asia. A special section on differentiating pediatric Crohn's disease from tuberculosis in children is included. This position paper provides a useful guide to clinicians in the surgical management, disease monitoring, and various health issues in children with IBD in Asia-Pacific region.

Use of Dual-Energy X-ray Absorptiometry in Children with Inflammatory Bowel Disease: A Large Single Centre Study

PURPOSE

Low bone mineral density (BMD) is a complication in children with inflammatory bowel disease (IBD). There are limited data evaluating dual-energy x-ray absorptiometry (DXA) as a screening tool for low BMD in children with IBD. We performed a single site retrospective analysis of DXA use.

METHODS

Children aged 5-18 years with IBD diagnosed between 2013 to 2017 at the Royal Children's Hospital, Australia, were included. Patient demographics, measures of disease activity, DXA scores, and factors related to BMD were collected.

RESULTS

Over a median follow up of 5.1 (4-6.4) years, 72/239 (30.1%) children underwent DXA, and 28/239 (11.7%) children had a second DXA. Our DXA practice differed to consensus guidelines regarding initial screening based on height and/or body mass index (BMI) z-score (8/17 [47.1%]), and repeat surveillance (13/42 [31.0%]). Children had a median lumbar spine (LS) z-score -0.80 (-1.65-0.075). Children with LS z-score≤-2.0 (n=14) had lower weight (6.57 [1.78-23.7] vs. 51.1 [26.5-68.7], p=0.0002) and height centiles (3.62 [1.17-17.1] vs. 42 [16.9-67.1], p=0.0001), and higher faecal calprotectin (FCP) (3041 [1182-4192] vs. 585 [139-2419], p=0.009) compared to children with LS z-score>-2.0. No fractures were reported. Of 28 children who underwent a second DXA 1.6 (1.1-2.2) years following initial DXA, no significant change in z-scores occurred.

CONCLUSION

Children with IBD had low BMD. In addition to height centile and weight centile, FCP was associated with lower BMD, and should be considered in DXA screening guidelines. Greater clinician awareness of DXA consensus guidelines is required. Future prospective studies are required.

Bone marrow adiposity in pediatric Crohn's disease

Patients with Crohn's disease often have low bone mineral density and an increased risk of osteoporosis. Although decreased bone formation can be seen at diagnosis, the underlying pathophysiology of suboptimal bone accrual remains poorly understood. We sought to evaluate a novel mechanism affecting osteogenesis in patients with Crohn's disease. In this case series, we evaluated bone marrow composition at the distal femur and proximal tibia of the left knee measured via magnetic resonance (MR) spectroscopy and relaxometry in five adolescents with the diagnosis of Crohn's disease. The subjects were enrolled prospectively between 2011 and 2013 at Boston Children's Hospital. Additional clinical information, including DXA scans to evaluate bone mineral density and body composition, and Crohn's disease history, such as glucocorticoid use and disease duration, were assessed. Healthy adolescents have persistent hematopoietic marrow with only 40 to 50 % fat in the long bone metaphyses. The current participants with Crohn's disease had increased marrow adiposity, with a mean fat fraction of 67.8 %. There appeared to be a trend towards higher fat fraction with shorter disease duration, while participants with the longest disease duration had the lowest fat fraction. Participants also had decreased bone density, increased fat mass, and lower lean mass, as assessed by DXA and compared to pediatric reference data. Our MRI results demonstrate increased marrow adiposity in children with Crohn's disease, especially early in the course of the disease. DXA may better demonstrate longer-term effects on bone. Additional studies are needed to evaluate bone marrow composition in these patients and to elucidate further the inverse relationship between marrow adipocytes and osteogenesis, as well as the relationship between bone marrow adiposity and body composition.

Young Adult Male Patients With Childhood-onset IBD Have Increased Risks of Compromised Cortical and Trabecular Bone Microstructures

BACKGROUND

Young adults with childhood-onset inflammatory bowel disease (IBD) have increased risks of low areal bone mineral density and low skeletal muscle mass. Volumetric BMD (vBMD), bone geometry and microstructures, in addition to possible associations with skeletal muscle index (SMI) and physical exercise have been scarcely studied in this patient group.

PATIENTS AND METHODS

In total, 49 young adult male patients with childhood-onset IBD and 245 age- and height-matched young adult male controls were scanned with high-resolution peripheral quantitative computed tomography. Bone geometry, vBMD, and bone microstructures were calculated as median values and compared between the patients and controls. Multivariable linear regression analyses were performed to determine the independent associations among IBD diagnosis, SMI (kg/m2), and physical exercise.

RESULTS

The group of young adult patients had, in comparison with the controls, significantly smaller median cortical area (126.1 mm2 vs151.1 mm2, P < .001), lower median total vBMD (296.7 mg/cm3 vs 336.7 mg/cm3, P < .001), and lower median cortical vBMD (854.4 mg/cm3 vs 878.5 mg/cm3, P < .001). Furthermore, the patients compared with the controls had lower median trabecular volume fraction (16.8% vs 18.2%, P < .001) and thinner median trabeculae (0.084 mm vs 0.089 mm, P < .001). The differences between the patients with IBD and controls persisted in multivariable analyses that included adjustments for SMI and physical exercise.

CONCLUSIONS

Young adult men with childhood-onset IBD are at increased risk of having reduced bone quality in both the cortical and trabecular bone structures compared with normative matched controls.

Early-Onset Osteoporosis

Osteoporosis is a skeletal disorder with enhanced bone fragility, usually affecting the elderly. It is very rare in children and young adults and the definition is not only based on a low BMD (a Z-score < - 2.0 in growing children and a Z-score ≤ - 2.0 or a T-score ≤ - 2.5 in young adults) but also on the occurrence of fragility fractures and/or the existence of underlying chronic diseases or secondary factors such as use of glucocorticoids. In the absence of a known chronic disease, fragility fractures and low BMD should prompt extensive screening for secondary causes, which can be found in up to 90% of cases. When fragility fractures occur in childhood or young adulthood without an evident secondary cause, investigations should explore the possibility of an underlying monogenetic bone disease, where bone fragility is caused by a single variant in a gene that has a major role in the skeleton. Several monogenic forms relate to type I collagen, but other forms also exist. Loss-of-function variants in LRP5 and WNT1 may lead to early-onset osteoporosis. The X-chromosomal osteoporosis caused by PLS3 gene mutations affects especially males. Another recently discovered form relates to disturbed sphingolipid metabolism due to SGMS2 mutations, underscoring the complexity of molecular pathology in monogenic early-onset osteoporosis. Management of young patients consists of treatment of secondary factors, optimizing lifestyle factors including calcium and vitamin D and physical exercise. Treatment with bone-active medication should be discussed on a personalized basis, considering the severity of osteoporosis and underlying disease versus the absence of evidence on anti-fracture efficacy and potential harmful effects in pregnancy.

Characterization of Skeletal Phenotype and Associated Mechanisms With Chronic Intestinal Inflammation in the Winnie Mouse Model of Spontaneous Chronic Colitis

BACKGROUND

Osteoporosis is a common extraintestinal manifestation of inflammatory bowel disease (IBD). However, studies have been scarce, mainly because of the lack of an appropriate animal model of colitis-associated bone loss. In this study, we aimed to decipher skeletal manifestations in the Winnie mouse model of spontaneous chronic colitis, which carries a MUC2 gene mutation and closely replicates ulcerative colitis. In our study, Winnie mice, prior to the colitis onset at 6 weeks old and progression at 14 and 24 weeks old, were compared with age-matched C57BL/6 controls. We studied several possible mechanisms involved in colitis-associated bone loss.

METHODS

We assessed for bone quality (eg, microcomputed tomography [micro-CT], static and dynamic histomorphometry, 3-point bending, and ex vivo bone marrow analysis) and associated mechanisms (eg, electrochemical recordings for gut-derived serotonin levels, real-time polymerase chain reaction [qRT-PCR], double immunofluorescence microscopy, intestinal inflammation levels by lipocalin-2 assay, serum levels of calcium, phosphorus, and vitamin D) from Winnie (6-24 weeks) and age-matched C57BL6 mice.

RESULTS

Deterioration in trabecular and cortical bone microarchitecture, reductions in bone formation, mineral apposition rate, bone volume/total volume, osteoid volume/bone surface, and bone strength were observed in Winnie mice compared with controls. Decreased osteoblast and increased osteoclast numbers were prominent in Winnie mice compared with controls. Upregulation of 5-HTR1B gene and increased association of FOXO1 with ATF4 complex were identified as associated mechanisms concomitant to overt inflammation and high levels of gut-derived serotonin in 14-week and 24-week Winnie mice.

CONCLUSIONS

Skeletal phenotype of the Winnie mouse model of spontaneous chronic colitis closely represents manifestations of IBD-associated osteoporosis/osteopenia. The onset and progression of intestinal inflammation are associated with increased gut-derived serotonin level, increased bone resorption, and decreased bone formation.

It starts from the womb: maximizing bone health

The foundation of bone health is established in utero. Bone accrual starts from the developing fetus and continues throughout childhood and adolescence. This process is crucial to achieve peak bone mass. Understanding factors that influence bone accrual before attainment of peak bone mass is thus critical to improve bone health and prevent osteoporosis, thereby reducing the burden of osteoporotic fractures in older women. In this review, we broadly outline factors influencing peak bone mass from pregnancy to infancy, childhood and adolescence with potential diseases and medications that may affect the optimum trajectory to maximizing bone health. It is estimated that a 10% increase in peak bone mass will delay the onset of osteoporosis by 13 years in a woman.

Pathogenesis of Musculoskeletal Deficits in Children and Adults with Inflammatory Bowel Disease

Musculoskeletal deficits are among the most commonly reported extra-intestinal manifestations and complications of inflammatory bowel disease (IBD), especially in those with Crohn’s disease. The adverse effects of IBD on bone and muscle are multifactorial, including the direct effects of underlying inflammatory disease processes, nutritional deficits, and therapeutic effects. These factors also indirectly impact bone and muscle by interfering with regulatory pathways. Resultantly, individuals with IBD are at increased risk of osteoporosis and sarcopenia and associated musculoskeletal morbidity. In paediatric IBD, these factors may contribute to suboptimal bone and muscle accrual. This review evaluates the main pathogenic factors associated with musculoskeletal deficits in children and adults with IBD and summarises the current literature and understanding of the musculoskeletal phenotype in these patients.

Bone Health in Pediatric Patients with IBD: What Is New?

PURPOSE OF THE REVIEW

Patients with inflammatory bowel disease (IBD) have increased bone fragility, demonstrated by increased fracture risk, and often have low bone density and altered bone geometry, but the underlying pathophysiology remains poorly understood.

RECENT FINDINGS

Children and adolescents with IBD appear to have decreased bone formation, at diagnosis, which frequently improves with treatment of their underlying IBD. There is a growing body of evidence regarding how the immune system interacts with bone metabolism. There are likely multi-factorial etiologies that contribute to suboptimal bone accrual and subsequent lack of peak bone mass attainment in growing patients with IBD. There appears to be differential effects dependent upon IBD sub-type and bone compartment. Pediatric patients with IBD require recognition of several risk factors that may adversely impact their bone accrual. Future studies are necessary to further delineate the effects of IBD on pediatric bone health.

Small and Large Intestine (II): Inflammatory Bowel Disease, Short Bowel Syndrome, and Malignant Tumors of the Digestive Tract

The small intestine is key in the digestion and absorption of macro and micronutrients. The large intestine is essential for the absorption of water, to allow adequate defecation, and to harbor intestinal microbiota, for which their nutritional role is as important as it is unknown. This article will describe the causes and consequences of malnutrition in patients with inflammatory bowel diseases, the importance of screening and replacement of micronutrient deficits, and the main indications for enteral and parenteral nutrition in these patients. We will also discuss the causes of short bowel syndrome, a complex entity due to anatomical or functional loss of part of the small bowel, which can cause insufficient absorption of liquid, electrolytes, and nutrients and lead to complex management. Finally, we will review the causes, consequences, and management of malnutrition in patients with malignant and benign digestive tumors, including neuroendocrine tumors (present not only in the intestine but also in the pancreas).

Clinical Criteria Can Identify Children With Osteopenia in Newly Diagnosed Crohn Disease

OBJECTIVES

Chronic inflammation of Crohn disease (CD) is associated with reduced bone mineral density (BMD). As bone mass is almost exclusively accrued during childhood, early recognition of osteopenia is especially important in pediatric CD. We aimed to identify variables associated with osteopenia to guide dual-energy X-ray absorptiometry (DXA) scan screening to those who most need it.

METHODS

This was a retrospective inception cohort study of children newly diagnosed with CD, and routinely referred to DXA scans. Demographic and explicit clinical data were recorded along with whole-body less head BMD, adjusted for age, sex, and height by z-scores.

RESULTS

Of the 116 included children (mean age 13 ± 3.1 years, 67 [58%] boys, mean body mass index [BMI] 16.7 ± 2.6), 63 (54%) had normal BMD (z-score > -1) or borderline osteopenia (-1 ≥ z-score > -2) and 53 (46%) had osteopenia (z-score ≤ -2). Osteopenia was associated with lower BMI z-score (-0.8 ± 1.2 vs -1.8 ± 1.1, P < 0.001) and higher PCDAI (33.7 ± 15.2 vs 25.7 ± 16.5; P = 0.009) than those with BMD z-score >-2. In total, 59% of children with BMI z-score <-0.5 had moderate-severe osteopenia and only 18% of those with higher z-scores. Multivariate logistic regression identified BMI z-score as the sole risk factor (OR 1.28 [95% CI 1.08-1.52], P = 0.005). BMI z-score ≥-0.5 excludes osteopenia with a sensitivity 87%, specificity 49%, NPV 82%, and PPV 59%.

CONCLUSIONS

Osteopenia was found in nearly half of children with newly onset CD. BMI z-score <-0.5 should prompt referral to DXA screening.

Factors influencing peak bone mass gain

Bone mass is a key determinant of osteoporosis and fragility fractures. Epidemiologic studies have shown that a 10% increase in peak bone mass (PBM) at the population level reduces the risk of fracture later in life by 50%. Low PBM is possibly due to the bone loss caused by various conditions or processes that occur during adolescence and young adulthood. Race, gender, and family history (genetics) are responsible for the majority of PBM, but other factors, such as physical activity, calcium and vitamin D intake, weight, smoking and alcohol consumption, socioeconomic status, age at menarche, and other secondary causes (diseases and medications), play important roles in PBM gain during childhood and adolescence. Hence, the optimization of lifestyle factors that affect PBM and bone strength is an important strategy to maximize PBM among adolescents and young people, and thus to reduce the low bone mass or osteoporosis risk in later life. This review aims to summarize the available evidence for the common but important factors that influence bone mass gain during growth and development and discuss the advances of developing high PBM.

Predicting Outcomes in Pediatric Crohn's Disease for Management Optimization: Systematic Review and Consensus Statements From the Pediatric Inflammatory Bowel Disease-Ahead Program

BACKGROUND & AIMS

A better understanding of prognostic factors within the heterogeneous spectrum of pediatric Crohn's disease (CD) should improve patient management and reduce complications. We aimed to identify evidence-based predictors of outcomes with the goal of optimizing individual patient management.

METHODS

A survey of 202 experts in pediatric CD identified and prioritized adverse outcomes to be avoided. A systematic review of the literature with meta-analysis, when possible, was performed to identify clinical studies that investigated predictors of these outcomes. Multiple national and international face-to-face meetings were held to draft consensus statements based on the published evidence.

RESULTS

Consensus was reached on 27 statements regarding prognostic factors for surgery, complications, chronically active pediatric CD, and hospitalization. Prognostic factors for surgery included CD diagnosis during adolescence, growth impairment, NOD2/CARD15 polymorphisms, disease behavior, and positive anti-Saccharomyces cerevisiae antibody status. Isolated colonic disease was associated with fewer surgeries. Older age at presentation, small bowel disease, serology (anti-Saccharomyces cerevisiae antibody, antiflagellin, and OmpC), NOD2/CARD15 polymorphisms, perianal disease, and ethnicity were risk factors for penetrating (B3) and/or stenotic disease (B2). Male sex, young age at onset, small bowel disease, more active disease, and diagnostic delay may be associated with growth impairment. Malnutrition and higher disease activity were associated with reduced bone density.

CONCLUSIONS

These evidence-based consensus statements offer insight into predictors of poor outcomes in pediatric CD and are valuable when developing treatment algorithms and planning future studies. Targeted longitudinal studies are needed to further characterize prognostic factors in pediatric CD and to evaluate the impact of treatment algorithms tailored to individual patient risk.

Muscle deficits with normal bone microarchitecture and geometry in young adults with well-controlled childhood-onset Crohn's disease

BACKGROUND

Muscle-bone deficits are common in pediatric Crohn's disease; however, few studies have assessed long-term musculoskeletal outcomes in adults with childhood-onset Crohn's disease. This study assessed the prevalence of musculoskeletal deficits in young adults with childhood-onset Crohn's disease compared with healthy controls.

METHODS

High-resolution MRI and MR spectroscopy were used to assess bone microarchitecture, cortical geometry and muscle area, and adiposity at distal femur and bone marrow adiposity (BMA) at lumbar spine. Muscle function and biomarkers of the muscle-bone unit were also assessed.

RESULTS

Twenty-seven adults with Crohn's disease with median (range) age 23.2 years (18.0, 36.1) and 27 age and sex-matched controls were recruited. Trabecular microarchitecture, cortical geometry and BMA were not different between Crohn's disease and controls (P > 0.05 for all). Muscle area was lower (P = 0.01) and muscle fat fraction was higher (P = 0.04) at the distal femur in Crohn's disease compared to controls. Crohn's disease participants had lower grip strength [-4.3 kg (95% confidence interval (CI), -6.8 to -1.8), P = 0.001] and relative muscle power [-5.0 W/kg (95% CI, -8.8 to -1.2), P = 0.01]. Crohn's disease activity scores negatively associated with trabecular bone volume (r = -0.40, P = 0.04) and muscle area (r = -0.41, P = 0.03).

CONCLUSION

Young adults with well-controlled Crohn's disease managed with contemporary therapies did not display abnormal bone microarchitecture or geometry at the distal femur but exhibited muscle deficits. The observed muscle deficits may predispose to musculoskeletal morbidity in future and interventions to improve muscle mass and function warrant investigation.

Growth and Puberty in Children with Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) are gastrointestinal tract pathologies of unknown etiology; they have an alternating trend, with active and silent phases. IBD are classified in two main forms: ulcerative colitis (UC) and Crohn’s disease (CD). Both have chronic and recurrent course, gastrointestinal symptoms, and extraintestinal manifestations. The altered immune response role seems to be important both in UC and CD. In the majority of cases, CD begins with abdominal pain, diarrhea, decrease in appetite, and weight loss; there can be also perianal fistulas, rhagades, and perianal recurrent abscesses. In addition, retarded growth and delayed puberty can precede the development of the disease or can even be predominant at onset. Growth retardation is found in 40% of IBD patients, but the underlying mechanism of this and other extra-intestinal manifestations are partially known: the main hypotheses are represented by malnutrition and inflammatory response during the active phase of the disease. The increased level of pro-inflammatory cytokines can influence growth, but also the onset of puberty and its progression. In addition, it could be essential to clarify the role and the possible effects of all the currently used treatments concerning growth failure and delayed puberty.

Incidence, Risk Factors and Evaluation of Osteoporosis in Patients With Inflammatory Bowel Disease: A Danish Population-Based Inception Cohort With 10 Years of Follow-Up

BACKGROUND

Patients with inflammatory bowel disease [IBD] including Crohn's disease [CD] and ulcerative colitis [UC] are at risk of developing metabolic bone disease. The aims here were to investigate the screening strategy, incidence and risk factors of osteoporosis in a prospective population-based inception cohort.

METHOD

Between 2003 and 2004 all incident patients diagnosed with CD and UC in a well-defined Copenhagen area were included and followed until 2015. Data were compared with a control population [at a ratio of 1:20]. Regression models were performed with several covariates. The sensitivity of the Danish registries for osteoporosis was also assessed.

RESULTS

A total of 513 patients were included [213 CD, 300 UC]. Overall, 338 (66%, CD: 164 [77%], UC: 174 [58%], p < 0.001] patients received ≥ 500 mg corticosteroid within a year, resulting in 781 patient-years at risk of osteoporosis. Of those, only 83 [10.6%] patient-years were followed by a dual-energy X-ray absorptiometry scan within the same or the following 2 years.Overall, 73 [14.2%] IBD patients (CD: 31 [14.6%], UC: 42 [14%]) and 680 [6.6%, p < 0.001] controls were diagnosed with osteoporosis during follow-up. The risk of osteoporosis was increased compared to the control population (odds ratio: CD: 2.9 [95% confidence interval: 2.0-4.1], UC: 2.8 [2.1-3.9]).

CONCLUSION

In this population-based inception cohort, the incidence of osteoporosis was significantly higher compared to a control population. Measurement of bone mineral density is infrequent, especially in patients at high risk of developing osteoporosis. These results demonstrate the need of further awareness of the risk of osteoporosis among IBD patients, and prospective population-based studies are warranted.

Longitudinal changes in bone mineral density in children with inflammatory bowel diseases

AIM

Children with inflammatory bowel disease (IBD) are prone to low bone mineral density (BMD). Our aim was to assess longitudinal changes in BMD in this population.

METHODS

A retrospective longitudinal study of children with IBD, treated at two tertiary centres in Israel, who underwent two BMD measurements by dual-energy X-ray absorptiometry (DXA). Changes in lumbar spine BMD (∆L1-4 z-scores) were examined for correlations with clinical characteristics.

RESULTS

The cohort included 41 patients (age at diagnosis 12.1 ± 3.5 years, 23 females).The mean interval between the scans was 3.4 ± 2.0 years. There was a trend towards improvement in L1-4 z-scores (-1.64 ± 1.02 vs -1.45 ± 0.83, P = .12). ∆L1-4 z-scores correlated positively with ∆weight-standard deviation scores (SDS), ∆height-SDS and ∆BMI-SDS, and with age at the second scan (R = .55, P < .01; R = .42, P < .01; R = .42, P = .01; R = .35, P = .02, respectively); and negatively with L1-4 z-scores at the first scan (R = -.63, P < .01). Stepwise linear regression analysis identified the first scan L1-4 z-scores and ∆weight-SDS as independent predictors of ∆L1-4 z-scores. An L1-4 z-score ≤-2 at the first DXA scan was associated with significant improvement at the second scan.

CONCLUSION

Improvement in BMD was more pronounced in children who gained weight or whose BMD was low at the first scan.

Partial enteral nutrition has no benefit on bone health but improves growth in paediatric patients with quiescent or mild Crohn's disease

BACKGROUND AND AIMS

Exclusive enteral nutrition induces remission, improves bone health and growth in paediatric Crohn's disease (CD) patients, but is highly demanding for patients. We investigated efficacy of partial enteral nutrition (PEN) on bone health, growth and course in CD patients and assessed microbial and metabolic changes induced by PEN.

METHODS

We performed a two centre, non-randomized controlled intervention study in quiescent CD patients aged <19 years. Patients in intervention group received a liquid formula providing ~25% of daily energy for one year. At baseline, after 3, 6, 9 and 12 months, we collected data on bone, muscle (peripheral quantitative computertomography), anthropometry, disease activity (weighted paediatric CD activity index), metabolomic profile (liquid chromatography mass spectrometry), and faecal microbiome (16S rRNA gene sequencing).

RESULTS

Of 41 CD patients, 22 received the intervention (PEN) (mean age 15.0 ± 1.9 years, 50% male), 19 served as controls (non-PEN) (12.8 ± 3.1 years, 58% male). At baseline, mean bone quality was comparable to reference population with no improvement during the intervention. Relapse rate was low (8/41, PEN 4/22 and non-PEN 4/19, ns). PEN was not associated with microbiota community changes (beta diversity) but significantly reduced species diversity. Metabolome changes with upregulation of phosphatidylcholines in PEN patients are likely related to lipid and fatty acid composition of the formula. PEN significantly improved growth in a subgroup with Tanner stage 1-3.

CONCLUSION

In our cohort of paediatric CD patients, PEN did not affect bone health but improved growth in patients with a potential to grow.

Perspective on skeletal health in inflammatory bowel disease

Osteopenia and osteoporosis are common features in inflammatory bowel disease (IBD), comprising both Crohn's disease and ulcerative colitis. Moreover, Crohn's disease is associated with increased fracture risk. The etiology of bone loss in IBD is multifactorial. It includes insufficient intake or absorption of calcium, vitamin D, and potassium; smoking; a low peak bone mass; a low body mass index; and decreased physical activity. In several studies, it has been shown that elevated concentrations of systemic and local pro-inflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interferon-γ (IFNγ), interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-13, and IL-17, present in IBD patients are potentially detrimental for bone metabolism and may be responsible for bone loss and increased fracture risk. This perspective aims to review the current literature on the role of inflammatory factors in the pathophysiology of skeletal problems in IBD and to suggest potential treatment to improve bone health, based on a combination of evidence and clinical and pathophysiological reasoning.

DSS-induced colitis produces inflammation-induced bone loss while irisin treatment mitigates the inflammatory state in both gut and bone

Chronic pediatric inflammatory bowel disease (IBD) leads to lack of bone accrual, bone loss, and increased fractures. Presently there is no cure, and many IBD treatments incur negative side effects. We previously discovered treatment with exogenous irisin resolved inflammatory changes in the colon, gut lymphatics, and bone in a mild IBD rodent model. Here we assess irisin treatment in severe IBD induced via dextran sodium sulfate (DSS). Male Sprague Dawley rats (2-mo-old) were untreated (Con) or given 2% DSS in drinking water. In week two, half of each group (Con + Ir and DSS + Ir) received injections of recombinant irisin (i.p., 2x/wk). After 4 weeks, gut inflammation was associated with declines in bone mineral density and cancellous bone volume. Furthermore, elevated osteocyte TNF-α, interleukin-6, RANKL, OPG, and sclerostin corresponded with higher osteoclast surfaces and lower bone formation rate in DSS animals as well as lower ultimate load. While irisin treatment improved colon inflammation, there were no improvements in bone density or bone mechanical properties; however, irisin elevated bone formation rate, decreased osteoclast surfaces, and reduced osteocyte pro-inflammatory factors. These data highlight the negative impact of chronic gut inflammation on bone as well as the therapeutic potential of irisin as an anti-inflammatory treatment.

Pubertal abnormalities in adolescents with chronic disease

Pubertal disorders in the context of chronic disease especially in those with chronic inflammatory disorders or those requiring prolonged periods of treatment with glucocorticoid are common reasons for referral to the paediatric endocrine clinic. Disorders of puberty are also common in adolescents with disability requiring management by paediatric endocrinologists. In these adolescents, impaired skeletal development is also observed and this can be associated with fragility fractures. Chronic inflammation, glucocorticoid and sub-optimal nutrition all impact on the hypothalamic-pituitary gonadal axis, and can also impact on skeletal development locally by their effects on the growth plate and bone. Addressing pubertal disorders is important to ensure adolescents with chronic disease are matched with their peers, promote adequate bone mass accrual and linear growth. Careful discussion with primary clinicians, the young person and the family is needed when instituting endocrine therapies to address puberty and manage bone health.

Linear growth and bone metabolism in pediatric patients with inflammatory bowel disease

OBJECTIVE

To review the pathophysiology and evaluation methods of linear growth and bone mineral density in children and adolescents diagnosed with inflammatory bowel disease.

SOURCE OF DATA

Narrative review carried out in the PubMed and Scopus databases through an active search of the terms: inflammatory bowel disease, growth, failure to thrive, bone health, bone mineral density, and children and adolescents, related to the last ten years, searching in the title, abstract, or keyword fields.

SYNTHESIS OF FINDINGS

Inflammatory bowel diseases of childhood onset may present as part of the clinical picture of delayed linear growth in addition to low bone mineral density. The presence of a chronic inflammatory process with elevated serum levels of inflammatory cytokines negatively interferes with the growth rate and bone metabolism regulation, in addition to increasing energy expenditure, compromising nutrient absorption, and favoring intestinal protein losses. Another important factor is the chronic use of glucocorticoids, which decreases the secretion of growth hormone and the gonadotrophin pulses, causing pubertal and growth spurt delay. In addition to these effects, they inhibit the replication of osteoblastic lineage cells and stimulate osteoclastogenesis.

CONCLUSION

Insufficient growth and low bone mineral density in pediatric patients with inflammatory bowel disease are complex problems that result from multiple factors including chronic inflammation, malnutrition, decreased physical activity, late puberty, genetic susceptibility, and immunosuppressive therapies, such as glucocorticoids.

A Systematic Review of Micronutrient Deficiencies in Pediatric Inflammatory Bowel Disease

BACKGROUND

This systematic review critically analyzes the current research on micronutrient deficiency in children with inflammatory bowel disease (IBD) and synthesizes these data to provide evidence-based guidelines for nutritional surveillance in this population.

METHODS

We searched 5 databases (Ovid Medline, PubMed, Scopus, CINAHL, and Cochrane Library) for studies evaluating micronutrients in patients with IBD using the following inclusion criteria: 1) original research, 2) published 1996 or later; 3) published in English; 4) human subjects; and 5) containing pediatric data. Studies were reviewed and included based on the strength of research methods. Data on the prevalence of micronutrient deficiencies in pediatric patients with IBD and risk factors for micronutrient deficiency in these patients were extracted from included studies and compared and discussed in preparation of the proposed guidelines and manuscript.

RESULTS

A total of 39 studies were included in the final review. The data presented in these studies show that iron deficiency and vitamin D deficiency are common in pediatric patients with IBD. Vitamin B12 and folate deficiency are rare. Zinc deficiency, while not common, occurs at a higher rate in patients with Crohn's disease than in healthy controls. There was limited data on vitamins A, E, and C, and selenium, but deficiency of these micronutrients seems rare.

CONCLUSIONS

We recommend annual surveillance of iron and vitamin D in pediatric patients with IBD regardless of disease activity or phenotype. Zinc should be monitored annually in patients with Crohn's disease. There is insufficient evidence to support routine screening for other micronutrient deficiencies.

Effects of Recombinant Human Growth Hormone in Children with Crohn's Disease on the Muscle-Bone Unit: A Preliminary Study

BACKGROUND/AIMS

There is limited information on the impact of recombinant human growth hormone (rhGH) on the muscle-bone unit in children with Crohn's disease (CD). In this pilot study, we report on the effects of rhGH on bone formation, dual-energy X-ray absorptiometry (DXA) total body (TB) bone mineral density adjusted for height and lumbar spine (LS) bone mineral apparent density (BMAD), and body composition.

METHODS

Prospective study of 8 children with CD (6 male), aged 14.8 years (9.0-16.4), who received rhGH for 24 months. Serum procollagen type 1 N-terminal propeptide (P1NP) was measured at baseline and at 6 months. DXA was performed every 6 months.

RESULTS

Six months of rhGH led to improvement in P1NP SDS adjusted for bone age from -3.6 (-7.9 to -0.9) to -2.4 (-3.7 to 0.4) (p = 0.01). At baseline, reduction in LS-BMAD and TB lean mass SDS was observed being -1.2 (-3.6 to 0.8) (p = 0.01 vs. zero) and -0.8 (-2.4 to 3.0) (p = 0.11 vs. zero), respectively. No significant changes were seen in DXA bone and muscle parameters over the 24 months.

CONCLUSION

Twenty-four months of therapy with rhGH in CD did not lead to an improvement in DXA BMD and lean mass, despite improvement in P1NP and linear growth.

Vitamin D therapy in children with inflammatory bowel disease: A systematic review

BACKGROUND

Vitamin D deficiency is highly prevalent in children with inflammatory bowel disease (IBD). This may contribute to an increased risk of poor bone health and may also influence the course of disease. An optimal treatment strategy of vitamin D therapy in children with IBD has not yet been established.

AIM

To analyse the published intervention studies of vitamin D therapy in children with IBD.

METHODS

A systematic review was conducted of clinical studies involving children with IBD (including Crohn disease or ulcerative colitis) who had received vitamin D therapy. Studies up to March 31^st 2018 were identified through MEDLINE, PubMed, EMBASE and the Cochrane Library. Search terms included synonyms of the following terms: vitamin D, paediatric, supplementation, IBD. References of included articles based on abstract were searched for other relevant articles. All relevant articles were accessed and reviewed in full text. Studies fitting the set criteria were included and the remainder were excluded.

RESULTS

Two hundred and seventy-seven discrete articles were identified. Following assessment of these articles included in the initial search and application of inclusion and exclusion criteria, ten published studies were included in this review. The included studies showed a heterogeneity in study design, inclusion and exclusion criteria, baseline demographics and treatment strategies. Treatment regimens differed in length, supplemented form of vitamin D and factors based upon which dosage was adjusted. Each of the reports included in this review concluded their vitamin D regimens to be safe and well-tolerated. Few of the included studies reported secondary outcomes on the efficacy of vitamin D treatment upon the clinical course of disease or markers of inflammation. The majority of included trials were not sufficient in raising serum vitamin D levels to an adequate level (30 ng/mL) in children with IBD with vitamin D deficiency.

CONCLUSION

The included trials featured diverse treatment regimens that were predominantly insufficient in correcting vitamin D deficiency or maintaining adequate levels in children with IBD. Better treatment regimens are required for the management of vitamin D deficiency in children with IBD.

Telephone Encounters Predict Future High Financial Expenditures in Inflammatory Bowel Disease Patients: A 3-Year Prospective Observational Study

BACKGROUND

Telephone activity is essential in management of complex chronic diseases including inflammatory bowel disease (IBD). Telephone encounters logged in the electronic medical record have recently been proposed as a surrogate marker of disease activity and impending health care utilization; however, the association between telephone calls and financial expenditures has not been evaluated.

STUDY

We performed a 3-year prospective observational study of telephone encounters logged at a tertiary referral IBD center. We analyzed patient demographics, disease characteristics, comorbidities, clinical activity, and health care financial charges by telephone encounter frequency.

RESULTS

Eight hundred one patients met inclusion criteria (52.3% female; mean age, 44.1 y), accounted for 12,669 telephone encounters, and accrued $70,513,449 in charges over 3 years. High telephone encounter frequency was associated with female gender (P=0.003), anxiety/depression (P<0.001), and prior IBD surgery (P<0.001). High telephone encounter categories had significantly more hospitalizations (P<0.001), IBD surgery (P<0.001), worse quality of life (P<0.001), more corticosteroid (P<0.001), biological (P<0.001), and opiate prescriptions (P<0.001). High telephone encounter frequency patients amassed higher total available charges in each year (P<0.001) and over the 3 years (P<0.001). Telephone encounters in 2009 (P=0.02) and 2010 (P<0.001) were significantly associated with financial charges the following year after controlling for demographic, utilization, and medication covariates.

CONCLUSIONS

Increased telephone encounters are associated with significantly higher health care utilization and financial expenditures. Increased call frequency is predictive of future health care spending. Telephone encounters are a useful tool to identify patients at risk of clinical deterioration and large financial expense.

Suppressor of cytokine signaling 2 (Socs2) deletion protects bone health of mice with DSS-induced inflammatory bowel disease

Individuals with inflammatory bowel disease (IBD) often present with poor bone health. The development of targeted therapies for this bone loss requires a fuller understanding of the underlying cellular mechanisms. Although bone loss in IBD is multifactorial, the altered sensitivity and secretion of growth hormone (GH) and insulin-like growth factor-1 (IGF-1) in IBD is understood to be a critical contributing mechanism. The expression of suppressor of cytokine signaling 2 (SOCS2), a well-established negative regulator of GH signaling, is stimulated by proinflammatory cytokines. Therefore, it is likely that SOCS2 expression represents a critical mediator through which proinflammatory cytokines inhibit GH/IGF-1 signaling and decrease bone quality in IBD. Using the dextran sodium sulfate (DSS) model of colitis, we reveal that endogenously elevated GH function in the Socs2^−/− mouse protects the skeleton from osteopenia. Micro-computed tomography assessment of DSS-treated wild-type (WT) mice revealed a worsened trabecular architecture compared to control mice. Specifically, DSS-treated WT mice had significantly decreased bone volume, trabecular thickness and trabecular number, and a resulting increase in trabecular separation. In comparison, the trabecular bone of Socs2-deficient mice was partially protected from the adverse effects of DSS. The reduction in a number of parameters, including bone volume, was less, and no changes were observed in trabecular thickness or separation. This protected phenotype was unlikely to be a consequence of improved mucosal health in the DSS-treated Socs2^−/− mice but rather a result of unregulated GH signaling directly on bone. These studies indicate that the absence of SOCS2 is protective against bone loss typical of IBD. This study also provides an improved understanding of the relative effects of GH/IGF-1 signaling on bone health in experimental colitis, information that is essential before these drugs are explored as bone protective agents in children and adults with IBD.

Summary: Using a mouse model of inflammatory bowel disease, this article provides an improved understanding of the relative effects of GH/IGF-1 on bone health in experimental colitis.

Causes of low peak bone mass in women

Peak bone mass is the maximum bone mass that accrues during growth and development. Consolidation of peak bone mass normally occurs during early adulthood. Low peak bone mass results from failure to achieve peak bone mass genetic potential, primarily due to bone loss caused by a variety of conditions or processes occurring at younger ages than usual. Recognized causes of low peak bone mass include genetic causes, endocrine disorders, nutritional disorders, chronic diseases of childhood or adolescence, medications, and idiopathic factors.

Increased bone matrix mineralization in treatment-naïve children with inflammatory bowel disease

Inflammatory bowel disease (IBD) affects many organ systems including the skeleton. In children with IBD, bone mineral density (BMD) and bone turnover are frequently low. Disturbances in bone mineralization density distribution (BMDD) are linked to alterations in bone material strength; however, BMDD has not previously been reported in children with chronic inflammatory disorders. The aim of this study was to characterize BMDD based on quantitative backscatter electron imaging in cancellous (Cn.) and cortical (Ct.) compartments from trans-iliac biopsy samples from a cohort of 20 treatment-naïve children at the time of their IBD diagnosis (12 males, mean age 14.5±2.3years). The outcomes were compared to pediatric reference BMDD data and correlation with revisited biochemical and histomorphometric outcomes was analyzed. BMDD in treatment-naïve children with IBD was shifted toward higher calcium concentrations compared to reference: (i) In cancellous bone, the most frequent calcium concentration (Cn.CaPeak+2.8%, p=0.004) and the portion of highly mineralized bone (Cn.CaHigh+52%, p=0.009) were increased. (ii) In cortical bone, the mineralization heterogeneity (Ct.CaWidth+17.0%, p=0.001) and Ct.CaHigh (+30.4%, p=0.006) were increased. (iii) Furthermore, significant correlations with serum alkaline phosphatase (ALP), bone-specific alkaline phosphatase (bsALP), and urinary crosslinked N-telopeptide of type I collagen (uNTX) were observed: the higher CaMean (the average calcium concentration), CaPeak and CaHigh, the lower were ALP, bsALP, and uNTX (p-value from <0.001 to 0.05). Children with treatment-naïve IBD have decreased bone turnover leading to a higher bone matrix mineralization density, findings which may contribute to compromised bone strength.

Bone Mass Development from Childhood into Young Adulthood in Patients with Childhood-onset Inflammatory Bowel Disease

BACKGROUND

Children who have inflammatory bowel disease (IBD) have increased risk of low bone mineral density (BMD). There is a scarcity of information on BMD development through puberty and into young adulthood in patients with childhood-onset IBD.

METHODS

We conducted a prospective longitudinal study of BMD in patients with childhood-onset IBD. In total, 74 children with IBD were followed into young adulthood, with a mean follow-up of 8.4 years. The BMD was assessed longitudinally using dual-energy X-ray absorptiometry of the lumbar spine, total hip and whole body, and related to anthropometric measures.

RESULTS

Young adult male patients with IBD had lower mean BMD Z-scores for the lumbar spine at -0.8 (±1.1 SD) and total hip at -0.5 (±0.9 SD), as compared to standard references. In young female patients, the BMD Z-scores were within the normal range at all 3 measured sites as compared to the standard references. There were no significant differences in the BMD Z-scores between patients with Crohn's disease and patients with ulcerative colitis. The female and male patients showed significantly improved mean lumbar spine BMD Z-scores during follow-up into young adulthood, indicating that bone accumulation in the lumbar spine continues beyond the expected age for achieving peak bone mass.

CONCLUSIONS

Male patients with childhood-onset IBD seem to have an increased risk of compromised BMD in young adulthood. Both female and male patients with IBD seem to increase their BMD beyond the age for expected peak bone mass (see Video abstract, Supplemental Digital Content 1, http://links.lww.com/IBD/B648).

Use of dual energy X-ray absorptiometry in pediatric patients

Dual Energy X-ray Absorptiometry (DXA) is a vital tool for assessing bone health in patients at risk for fragility fractures. In pediatric patients, this technology is used in conjunction with clinical fracture history to diagnosis osteoporosis and monitor treatment response. Childhood and adolescence is characterized by linear growth and bone mass accrual; thus there are important differences in the interpretation of bone measurements obtained by DXA in these young patients. This review aims to explore the current indications for DXA use and interpretation of DXA in the pediatric age group using currently available reference databases. Limitations of DXA in pediatric patients, specifically in children with short stature, will be explored. We will review several pathophysiologic mechanisms that may lead to low bone density in children, discussing representative diseases and the recommendations for monitoring bone health with DXA in these conditions. Finally, we will highlight new methods by which DXA imaging can gather additional information on bone health in children and may improve our ability to predict fractures and osteoporosis.

Musculoskeletal system in children and adolescents with inflammatory bowel disease: normal muscle force, decreased trabecular bone mineral density and low prevalence of vertebral fractures

Low bone mineral density (BMD) and an increased fracture incidence are two extraintestinal complications associated with inflammatory bowel disease (IBD). We aimed to evaluate musculoskeletal traits and assess vertebral fracture (VF) rate in children and adolescents with IBD. Seventy patients with IBD with a median age of 13.8 years were included. The BMD and geometric parameters of the non-dominant tibia were assessed using pQCT. Dynamic muscle functions were evaluated using jumping mechanography. VFs were assessed according to the semiquantitative standardized method by Genant. The muscle functions adjusted for the patients' weight did not differ from the reference population. A low trabecular BMD (Z-score - 1.6; p < 0.001) and cortical thickness (Z-score - 0.7; p < 0.001) were found in children and adolescents with IBD. Conversely, an increased cortical BMD (Z-score 1.1; p < 0.001) was noted. No significant association was found between the 25-OHD serum levels and the bone or muscle measurements. One patient with asymptomatic VF was identified.

CONCLUSION

IBD in childhood or adolescents affects bones but not muscles. Bone changes are independent of the 25-OHD serum level. A thoracolumbar spine X-ray should not be routinely recommended in children with IBD. What is Known: • Low bone mineral density and an increased fracture rate are the complications associated with IBD. • Bone strength and structural development is strongly dependent on skeletal muscle stimulation. What is New: • Children with IBD have altered bone density and geometry but normal dynamic muscle functions. • Thoracolumbar spine X-ray should be indicated on an individual basis in children with IBD.

Association between primary biliary cholangitis and osteoporosis: meta-analysis

The relationship between primary biliary cholangitis (PBC, previously termed primary biliary cirrhosis) and risks of osteoporosis remains controversial. This meta-analysis was designed to comprehensively analyze the association between PBC and osteoporosis. We conducted a systematic literature search of the PubMed, EMBASE, and Web of Science. Either fixed or random effects models were applied to assess bone mineral density (BMD), osteoporosis rates, and fractures in PBC patients and normal controls. A total of eight studies were included (including 1643 PBC patients and 10,921 controls). PBC patients had a relative risk (RR) of 2.79 (95% CI 1.26 to 6.16) for the development of osteoporosis, lower lumbar spine BMD (95% CI - 0.13 to - 0.04, P = 0.0002), hip BMD (95% CI - 0.13 to - 0.03, P = 0.002), and lumbar spine t score (95% CI - 1.69 to - 1.02, P < 0.00001) than controls. Moreover, PBC patients had an OR of 1.86 (95%CI 1.54 to 2.24, P < 0.00001) for the development of fractures. Collectively, this meta-analysis indicates that PBC patients were more likely to suffer from osteoporosis. Given the limited literature available, better designed and larger scale primary studies will be required to confirm our conclusion.

Bone Mineralization and Fracture Risk Assessment in the Pediatric Population

Identifying children most susceptible to clinically significant fragility fractures (low trauma fractures or vertebral compression fractures) or recurrent fractures is an important issue facing general pediatricians and subspecialists alike. Over the last decade, several imaging technologies, including dual-energy X-ray absorptiometry and peripheral quantitative computed tomography, have become useful to identify abnormal bone mineralization in children and in adolescents. This review aimed to summarize the latest literature on the utility of these modalities as they pertain to use in pediatrics. In addition, we review several disease states associated with poor bone health and increased fracture risk in children, and discuss the implications of low bone mineral density in these patients. Finally, we will highlight the gaps in knowledge with regard to pediatric bone health and make recommendations for future areas of research.

Pediatric-onset inflammatory bowel disease poses risk for low bone mineral density at early adulthood

BACKGROUND

Inflammatory bowel disease (IBD) is known to pose a risk for low bone mineral density (BMD) in children and adults. We aimed to evaluate the impact of pediatric-onset IBD on BMD in adulthood.

METHODS

Records of pediatric-IBD patients were retrospectively reviewed for documentation of dual-energy X-ray absorptiometry (DXA) scans in adulthood. BMD was expressed as z-score.

RESULTS

Sixty one patients were included. Mean (±SD) age at diagnosis was 14.7 (±2.4) years. Mean age at first DXA scan in adulthood was 23.9 years (±4.8). Median BMD z-score was -1.2 SD (IQR, -1.8 to -0.4), significantly lower than expected in normal population (p<0.001). Osteopenia (BMD z-score ≤-1 SD) was noted in 44.3% (n=27), and osteoporosis (BMD z-score ≤-2.5 SD) in 8.2% (n=5). Bone-status showed no correlation with age, disease severity, vitamin D status at diagnosis, IBD subtype or duration of disease. Positive correlation (r=0.306) was identified between low weight z-score at diagnosis and abnormal bone-status in adulthood. Among 36 patients with multiple DXA scans, there was no significant change in BMD during follow-up of 2.4 years.

CONCLUSIONS

Osteopenia and osteoporosis are frequent in adult IBD patients with pediatric-onset disease and correlates with low weight z-score at diagnosis.

Vitamin D status in relation to Crohn's disease: Meta-analysis of observational studies

OBJECTIVES

Inconsistent findings have been published regarding vitamin D status among patients with Crohn's disease (CD) and the association with disease severity. We aimed to perform a meta-analysis evaluating serum 25-hydroxy vitamin D and 1,25 dehydroxyvitamin D among CD patients compared with healthy and non-healthy controls, the prevalence of vitamin D deficiency, and the association with disease.

METHODS

We searched MEDLINE, SCOPUS, EMBASE, and Google Scholar up to March 2015 for observational studies assessing serum vitamin D levels in CD patients. A total of 63 studies were included in the following four meta-analyses: 1) a meta-analysis on the mean difference of 25(OH)D levels in CD patients compared with healthy (number of studies = 27) and non-healthy (n = 25) controls; 2) a meta-analysis on the mean difference of 1,25(OH)2 D3 levels in CD patients compared with healthy (n = 7) and non-healthy (n = 8) controls; 3) a meta-analysis on the prevalence of vitamin D deficiency (n = 34); 4) a meta-analysis on the correlation coefficients between vitamin D status severity of CD (n = 6). Subgroup analysis and meta-regression were used to discover possible sources of between-study heterogeneity.

RESULTS

It was found that CD patients had lower levels of 25(OH)D compared with healthy (-3.99 ng/mL; 95% confidence interval [CI]: -5.91 to -2.08) but not non-healthy controls (-1.07 ng/mL; 95% CI: -2.84 to 0.70). There was also no significant mean difference for 1,25(OH)2 D3 for both healthy and non-healthy controls. Meta-analysis on the prevalence of vitamin D deficiency showed an overall prevalence of 57.7% (95% CI: 0.502-0.649). An inverse association was observed between serum vitamin D and severity of CD (-0.36; 95% CI: -0.48 to -0.24). Meta-regression showed that mean levels of 25(OH)D were decreased 0.09 for each unit change of latitude among CD patients compared with healthy controls (B = -0.09, P = 0.004, I(2) residual = 86.08%).

CONCLUSIONS

We found that patients with Crohn's disease had lower serum 25(OH)D concentrations compared with their healthy counterparts, and more than half of them have hypovitaminosis D. Moreover, there was an inverse correlation between circulating 25(OH)D concentrations and severity of Crohn's disease.

Management of endocrine disease: Secondary osteoporosis: pathophysiology and management

Osteoporosis is a skeletal disorder characterized by decreased mass and compromised bone strength predisposing to an increased risk of fractures. Although idiopathic osteoporosis is the most common form of osteoporosis, secondary factors may contribute to the bone loss and increased fracture risk in patients presenting with fragility fractures or osteoporosis. Several medical conditions and medications significantly increase the risk for bone loss and skeletal fragility. This review focuses on some of the common causes of osteoporosis, addressing the underlying mechanisms, diagnostic approach and treatment of low bone mass in the presence of these conditions.

Improvements in Bone Density and Structure during Anti-TNF-α Therapy in Pediatric Crohn's Disease

CONTEXT

Pediatric Crohn's Disease (CD) is associated with deficits in trabecular bone mineral density (BMD) and cortical structure, potentially related to TNF-α effects to decrease bone formation and promote bone resorption.

OBJECTIVE

This study aimed to examine changes in bone density and structure in children and adolescents with CD following initiation of anti-TNF-α therapy.

DESIGN AND PARTICIPANTS

Participants (n = 74; age 5-21 years) with CD completed a 12-month prospective cohort study.

MAIN OUTCOME MEASURES

Tibia peripheral quantitative computed tomography scans were obtained at initiation of anti-TNF-α therapy and 12 months later. Musculoskeletal outcomes were expressed as sex-and race-specific z scores relative to age, based on >650 reference participants.

RESULTS

At baseline, CD participants had lower height, trabecular BMD, cortical area (due to smaller periosteal and larger endocortical circumferences), and muscle area z scores, compared with reference participants (all P < .01). Pediatric CD activity index decreased during the 10-week induction (P < .001), in association with subsequent gains in height, trabecular BMD, cortical area (due to recovery of endocortical bone), and muscle area z scores over 12 months (height P < .05; others P < .001). Bone-specific alkaline phosphatase levels, a biomarker of bone formation, increased a median of 75% (P < .001) during induction with associated 12-month improvements in trabecular BMD and cortical area z scores (both P < .001). Younger age was associated with greater increases in trabecular BMD z scores (P < .001) and greater linear growth with greater recovery of cortical area (P < .001).

CONCLUSIONS

Anti-TNF-α therapy was associated with improvements in trabecular BMD and cortical structure. Improvements were greater in younger and growing participants, suggesting a window of opportunity for treatment of bone deficits.

The Protective Effects of Exclusive Enteral Nutrition Formulas on Growth Factor Expression and the Proximal Tibial Epiphyseal Growth Plate in a TNBS-Induced IBD Rat Model

OBJECTIVE

This study aimed to evaluate the effectiveness of different types of nutritional formulas in a rat model of TNBS-induced IBD.

METHODS

IBD was induced with TNBS in 4-week-old rats that were then fed different exclusive enteral nutrition diets for 7 days. The length of the tibia and the number of chondrocytes in the proximal tibias were analyzed at 7 days after supplementation. Immunohistochemical analysis, ELISA and real-time PCR were performed to evaluate the levels of growth hormone receptor (GHR) and insulin-like growth factor-I receptor (IGF-IR), the growth factors IGF-I and insulin-like growth factor-binding protein-3 (IGFBP3) , bone morphogenetic protein (BMP)-2 and BMP-6 respectively.

RESULTS

The results demonstrated that the tibia length of the peptide formula group was longer than that of the IBD-Modulen(®) formula and normal diet groups (P < 0.05). Furthermore, the number of chondrocytes of the proximal tibial was more pronounced in the peptide formula group compared to the other groups (P < 0.05). The peptide formula was also more effective in increasing the expression of GHR compared to the other groups (P < 0.05), while the expression of IGF-IR was not significantly different (P > 0.05). In addition, the IGF-I and IGFBP3 levels were more pronounced in the peptide formula supplement group (P < 0.05), and the expression of BMP-2 and BMP-6 mRNA in the proximal tibia growth plate from the peptide formula group was higher than that in the ordinary formula and normal diet groups (P < 0.05).

CONCLUSIONS

EEN, and particularly a peptide formula, exerted protective effects on the proximal tibial epiphyseal growth plate in a TNBS-induced IBD model.

Piroxicam treatment augments bone abnormalities in interleukin-10 knockout mice

BACKGROUND

Osteoporosis and fractures are common complications of inflammatory bowel disease. The pathogenesis is multifactorial and has been partly attributed to intestinal inflammation. The aim of this study was to evaluate bone status and assess the association between bone loss and gut inflammation in an experimental colitis model.

METHODS

Colitis was induced in interleukin-10 knockout mice (PAC IL-10 k.o.) by peroral administration of piroxicam for 12 days. The degree of colitis was assessed by clinical, macroscopic, and microscopic evaluation. Trabecular and cortical bone microarchitecture of tibia were determined using micro-computed tomography. Moreover, the serum levels of bone formation and bone resorption biomarkers were measured, and inflammatory protein profiling was performed on colons.

RESULTS

PAC IL-10 k.o. mice developed severe colitis, characterized by hyperplasia and focal transmural inflammation, which was consistent with Crohn's disease-like pathology. The gut inflammation was accompanied by a 14% and 12% reduction in trabecular thickness relative to piroxicam-treated wild type and untreated wild type mice, respectively (P < 0.001). The trabecular bone structure was also changed in PAC IL-10 k.o. mice, whereas no differences in cortical bone geometry were observed. The trabecular thickness was inversely correlated with serum levels of CTX (r = -0.93, P = 0.006). Moreover, numerous inflammatory mediators, including RANKL and osteoprotegerin, were significantly increased in the colon of PAC IL-10 k.o. mice.

CONCLUSIONS

PAC IL-10 k.o. mice develop bone loss and changed trabecular structure, as a result of increased bone resorption. Thus, the PAC IL-10 k.o. model could be a useful experimental model in preclinical research of inflammatory bowel disease-associated bone loss.