Metabolic bone disease is present at diagnosis in patients with inflammatory bowel disease

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.

Assessment of gastrointestinal function and its' effect on bone mineral density and body composition in hypermobility spectrum disorder and hypermobile Ehlers-Danlos syndrome

BACKGROUND

Hypermobile Ehlers-Danlos Syndrome (hEDS) and Hypermobility Spectrum Disorders (HSD) are associated with hypermobility, musculoskeletal pain, a decreased bone mineral density (BMD) and gastrointestinal (GI) complications. The role of GI symptoms and diet in BMD has not been established in this population. The GI complications can lead to an energy deficit due to lack of essential macronutrients. The primary objective of this study was to determine the severity of GI symptoms compared to body composition and BMD in individuals with hEDS/HSD. The secondary objective is to examine GI symptoms on energy balance, body composition and strength.

METHODOLOGY

This study was IRB approved. Eighteen female participants (aged 28.2 ± 4.9; BMI 22.5 ± 4.9) with a diagnosis of hEDS or HSD and 18 female healthy control participants (aged 28.1 ± 3.8; BMI 22.8 ±3.9) signed consent to participate. Participants were matched by sex, age, and BMI. The Gastrointestinal Symptom Rating Scale (GSRS) was used to investigate severity of GI symptoms. Dual X-ray absorptiometry was used to determine body composition (body fat%, lean body mass (LBM). BMD was measured by Z- scores of both femurs and lumbar spine. Resting metabolic rate (RMR) was measured using indirect calorimetry and strength was determined using a hand grip dynamometer.

RESULTS

All hEDS/HSD participants reported GI symptoms. There was no difference in body composition between hEDS/HSD and controls. Participants with hEDS/HSD had lower BMD both femoral z scores (p=0.02,0.004) and spine z scores (p= 0.04). There was no difference in caloric intake between groups; yet both groups demonstrated caloric deficits. Additionally, hEDS/HSD consumed less protein and more carbohydrates (p=0.03, p=0.03). There were no differences in grip strength.

CONCLUSIONS

This study identified that pre-menopausal women with hEDS/HSD presented with significant GI complications and lower BMD than age matched controls. The GI complications and the reduced protein intake long-term may have a lasting impact on bone health. This study found that the GSRS identified and quantified GI symptoms in persons with hEDS/HSD. Future studies are needed for the longitudinal effects of a caloric/protein deficit in this population and to help guide future preventive and nutritional treatment approaches in individuals with hEDS/HSD.

The 25(OH)D3, but Not 1,25(OH)2D3 Levels Are Elevated in IBD Patients Regardless of Vitamin D Supplementation and Do Not Associate with Pain Severity or Frequency

Due to its immunomodulatory effect, vitamin D has been associated with clinical parameters and outcomes in inflammatory bowel diseases (IBDs) which are chronic conditions of the gastrointestinal tract. Upon synthesis or digestion, vitamin D is metabolized in the liver to form 25(OH)D3, the major circulating metabolite. Further renal hydroxylation generates 1,25(OH)2D3, the most potent metabolite. Our aim was to examine the association between vitamin D levels, and its supplementation and pain intensity in 39 IBD patients and 33 healthy individuals. 25(OH)D3 and 1,25(OH)2D3 serum levels were measured. Each subject filled out visual analog scale (VAS) and Laitinen’s pain assessment scales. Laboratory results were obtained, and disease activity was assessed. Linear regression was employed to investigate the correlation between 25(OH)D3, 1,25(OH)2D3 and pain intensity, clinical activity parameters, C-reactive protein, disease duration, and dietary habits. In IBD patients, 25(OH)D3 was increased, whereas 1,25(OH)2D3 was not. Vitamin D3 supplementation did not influence their levels. No correlation was found between pain scores, disease activity, inflammatory status, disease duration or dietary habits and both forms of vitamin D. Elevated 25(OH)D3 and normal 1,25(OH)D3 were found in IBD patients as compared to the controls. We discovered no effect from supplementation and no association between pain severity and vitamin D.

Bone Health in Patients With Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD) is a chronic inflammatory medical condition with relapses and remission. Metabolic bone disease, including osteoporosis, is associated with IBD and imparts a significant morbidity if pathologic fractures were to occur. There has been a significant amount of research that evaluated the pathophysiology and associations between IBD and osteoporosis. Although corticosteroids contribute to the risk of low bone mineral density, osteoporosis and fractures, older age, female gender, smoking, and family history of fracture have been shown to contribute. Additionally, intestinal inflammation affects bone resorption and formation through proinflammatory cytokines such as tumor necrosis factor-a, interleukin-1, and interleukin-6 further accelerating bone loss. Little information is available on standardizing screening or treatment. It is important to recognize the risk factors that are associated with IBD and osteoporosis to identify the patient population at risk and initiate treatment/prevention strategies early. Treatment can include calcium, vitamin D, or bisphosphonates. Some studies showed benefit of treating the underlying IBD to improve bone mineral density.

Bone mineral density is negatively correlated with ulcerative colitis: a systematic review and meta-analysis

BACKGROUND

Newer epidemiological studies suggest that the incidence of ulcerative colitis might be increasing rapidly. Furthermore, osteoporosis in ulcerative colitis patients has gained great attention, but the epidemiologic evidence remains controversial. Therefore, a meta-analysis was performed to explore the association between bone density and ulcerative colitis.

METHODS

Two investigators used PubMed, EMBASE and the Cochrane Library databases to identify all studies published before August 2019. Depending on the outcomes, investigators divided these studies into four groups (OR, SMD [BMD], SMD [z-score] and SMD [t-score]). To address the use of steroids, which is a major confounding factor in this analysis, another subgroup analysis of studies of steroid-free patients was conducted. Additionally, heterogeneity, sensitivity and stratified analyses were also performed.

RESULTS

A total of 13 cross-sectional studies that involved 1154 participants were included in the present meta-analysis, and three of them were included in the steroid-free subgroup analysis. The pooled OR was 6.41 (95% CI 2.59-15.87) and the pooled SMD (BMD), SMD (t-score) and SMD (z-score) were - 0.24 (95% CI - 0.44 to - 0.04), - 0.55 (95% CI - 0.72 to - 0.37), and - 0.38 (95% CI - 0.56 and - 0.19), respectively. Since steroids are a significant confounder, the pooled SMD of the steroid-free subgroup was - 0.55 (- 0.85 to - 0.25), which revealed a strong negative relationship between bone density and ulcerative colitis in steroid-free patients. Additionally, other subgroup analyses also revealed a strong relationship.

CONCLUSIONS

This meta-analysis provides evidence for the potential association between ulcerative colitis and decreased bone density. It is essential for clinicians to consider bone mineral density in ulcerative colitis patients regardless of steroid-therapy.

Crohn's disease patient serum changes protein expression in a human mesenchymal stem cell model in a linear relationship to patients' disease stage and to bone mineral density

BACKGROUND

Crohn's disease (CD) is associated with a higher prevalence of osteoporosis, a complication that is recognized as a significant cause of morbidity. Its pathogenesis is controversial, but the activity of CD is one contributing factor.

METHODS

We stimulated SCP-1 cells (mesenchymal stem cell line) under osteogenic conditions with serum from adult patients with CD in the symptomatic phase (SP) and in remission (R) and with control sera. Concentrations of IL-6, IL-1 beta, and TNF alpha in the sera were measured. Patients were classified as normal or osteopenic/osteoporotic based on bone mineral density (BMD) T-score measurements. After 14 days in culture, protein expression and gene ontology (GO) annotation analysis was performed.

RESULTS

Cytokine concentrations (IL-6, IL-1 beta, TNF alpha) varied within sera groups. None of the cytokines were significantly increased in the symptomatic phase compared to remission. Protein analysis revealed 17 proteins regulated by the SP versus R phase sera of disease. A linear relationship between CDAI (Crohn's disease activity index) and normalized protein expression of APOA1 and 2, TTR, CDKAL1 and TUBB6 could be determined. Eleven proteins were found to be differentially regulated comparing osteoporosis-positive and osteoporosis-negative sera. Gene annotation and further analysis identified these genes as part of heme and erythrocyte metabolism, as well as involved in hypoxia and in endocytosis. A significant linear relationship between bone mineral density and normalized protein expression could be determined for proteins FABP3 and TTR.

CONCLUSION

Our explorative results confirm our hypothesis that factors in serum from patients with CD change the protein expression pattern of human immortalized osteoblast like cells. We suggest, that these short time changes indeed influence factors of bone metabolism.

Pregnant Women with Inflammatory Bowel Disease Are at Increased Risk of Vitamin D Insufficiency: A Cross-Sectional Study

BACKGROUND AND AIMS

Vitamin D insufficiency is prevalent in individuals with inflammatory bowel disease [IBD], as well as in pregnant women; however, the prevalence of vitamin D insufficiency in pregnant women with IBD is unknown. This study assessed the prevalence of vitamin D insufficiency in pregnant women with IBD and the adequacy of recommended supplementation.

METHODS

A cross-sectional study was conducted in pregnant women with inflammatory bowel disease [Crohn's disease = 61, ulcerative colitis = 41] and without inflammatory bowel disease [n = 574]. Chi square tests and log binomial regression were used to examine the prevalence of vitamin D insufficiency. Covariates included ethnicity and season. Adequacy of vitamin D supplementation during pregnancy was also assessed.

RESULTS

The prevalence of vitamin D insufficiency [25-OHD ≤75 nmol/L] in those with Crohn's disease was 50.8% (95% confidence interval [CI]: 38.4%-63.2%) and 60.9% [95% CI: 45.3%-74.7%] with ulcerative colitis compared with 17.4% [95% CI: 14.6%-20.8%] without inflammatory bowel disease. Women with inflammatory bowel disease were more likely to be vitamin D insufficient after adjusting for ethnicity and season (Crohn's disease-adjusted relative risk [aRR] = 2.98,;: 2.19-4.04; ulcerative colitis-aRR = 3.61; 95% CI: 2.65-4.93). Despite vitamin D supplementation, 32.3% [95% CI: 17.8%-51.2%] of those with Crohn's disease, 58.3% [95% CI: 37.1%-76.9%] of those with with ulcerative colitis, and 10.8% [95% CI: 6.9%-16.6%] of those without inflammatory bowel disease were still vitamin D insufficient.

CONCLUSIONS

Pregnant women with inflammatory bowel disease are at increased risk of vitamin D insufficiency compared with those without inflammatory bowel disease. The current guidelines for vitamin D supplementation may be inadequate for pregnant women with inflammatory bowel disease.

Immunomodulatory and Immunosuppressive Roles of 1α,25(OH)2D3 in Autoimmune Diseases

Autoimmune diseases are pathological conditions characterized by abnormal responses, accompanied by autoantibodies to self-molecules. The role of vitamin D in autoimmune diseases has increased significantly in the recent past from its functions in calcium and phosphate homoeostasis, and it is now involved in the regulations and proliferations of Th1 and Th17 lymphocyte. 1α,25(OH)2D3 is very important in ameliorations of inflammatory disorders arising from autoimmune diseases, but the mechanism by which this is performed is still a bone of contentions. This review aimed to highlight the existing facts about the roles of Vitamin D in the treatment and management of autoimmune diseases. An extensive online literature search was conducted using PubMed, MEDLINE and Scopus. Accumulated bodies of research evidence are available which demonstrates that Vitamin D has a very important part to play in the regulation of immune responses in autoimmune diseases. Some of the authors suggested that Vitamin D3 carry-out its immunosuppressive and immune modulatory action, through its actions on antigen-presenting cells and activated T and B cells with the help of Vitamin D receptors present on the each of these cells. Vitamin D supplementation assists in autoimmune disorders by making qualitative and quantitative changes in the immune system (downregulation of Th1 and upregulations of Th2 cells). This resulted in the body to be more tolerant of self and less likely to mount autoimmune responses.

A 1-year prospective study of the effect of infliximab on bone metabolism in inflammatory bowel disease patients

OBJECTIVES

Infliximab (IFX) treatment has shown potentially beneficial effects on bone metabolism in inflammatory bowel disease (IBD) patients. We aimed to prospectively evaluate the impact of IFX treatment on bone metabolism in antitumour necrosis factor (TNF)-α-naive IBD patients using established bone metabolism markers and an in-vitro osteoblast model.

MATERIALS AND METHODS

A total of 37 anti-TNFα-naive IBD patients and 20 healthy controls were included. All measurements were performed at baseline and repeated in IBD patients following IFX therapy. Bone mineral density was measured by dual-energy X-ray absorptiometry. Parathyroid hormone, vitamin D, osteoprotegerin, soluble receptor activator of nuclear factor B ligand and proinflammatory and anti-inflammatory cytokines were measured. Bone formation was measured using osteocalcin (OC) and procollagen type 1N propeptide, and bone resorption was measured using serum type 1 collage c-telopeptide. The effect of control and IBD patient sera on human osteoblast viability and differentiation was analysed.

RESULTS

OC level was higher in controls than IBD patients (P=0.018). After IFX, OC and procollagen type 1N propeptide increased significantly (P=0.002 and 0.011) and (P<0.001 and P=0.016) at weeks 6 and 30 after treatment, respectively. There was a nonsignificant decrease in serum type 1 collage c-telopeptide. After IFX therapy, proinflammatory cytokines TNF-α, interleukin-6 and interleukin-13 decreased significantly (P=0.016, week 54; P=0.005, week 6 and P=0.025, week 6), respectively. Sera from IBD patients before IFX showed increased osteoblast viability compared with the controls (P=0.003 to P<0.005), but induced reduced osteoblast differentiation. After IFX, viability reduced to control levels, but osteoblast differentiation increased (P=0.041).

CONCLUSION

IFX treatment induced beneficial effects on bone metabolism. Osteoblast culture results suggest that IBD patients may have increased osteoblast viability, but reduced differentiation, which has implications for bone strength.

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.

Adalimumab Therapy Has a Beneficial Effect on Bone Metabolism in Patients with Crohn's Disease

BACKGROUND

Infliximab has been shown to have beneficial effects on bone metabolism in patients with Crohn's disease (CD) although as yet the exact mechanisms have not been fully elucidated.

AIM

To evaluate the impact of adalimumab therapy on bone metabolism using a combined in vivo and in vitro model.

METHODS

Parathyroid hormone, vitamin D, bone formation markers, bone resorption marker, pro-inflammatory cytokines, anti-inflammatory cytokines, osteoprotegerin, and sRANKL were measured in control patients and pre- and post-treatment with adalimumab in CD patients. The effect of control patients' and pre- and post-treatment CD patients' sera on human osteoblasts (hFOB 1.19) in vitro cell viability and differentiation was also analyzed.

RESULTS

There was a significant increase in bone formation markers osteocalcin (P < 0.05) and procollagen type 1 N-terminal propeptide (P < 0.01) at 1 and 3 months post-treatment. Moreover, there was a sustained but not significant fall in serum CTx, a bone resorption marker. No significant change was seen over time with other parameters measured. Serum from CD patients pre-treated with adalimumab showed increased osteoblast viability compared with that of post-treated patients at 6 months (P = 0.002) and controls. However, post-adalimumab treatment sera at 6 months appeared to increase osteoblast differentiation (P = 0.001), which is likely to be important in new bone formation.

CONCLUSIONS

This first study evaluating the role of adalimumab as a possible bone protector in Crohn's disease patients has shown that similar to infliximab, adalimumab has complex and potentially beneficial effects on bone metabolism.

The Role of Vitamin D in Inflammatory Bowel Disease

Vitamin D is known to be vital in maintaining bone health, mineralisation and for fracture prevention. It has also been implicated in a number of autoimmune diseases and has therefore been studied for its potential role in Inflammatory Bowel Disease (IBD). This review looks at the current literature on the role of vitamin D and its potential role as an immunomodulator, disease modifier and bone health in IBD patients. There is substantial supporting evidence of an important role from epidemiological, genetic and immunological studies, but there is also conflicting evidence and nothing proving to be definitive from clinical studies. There are also a number of confounders with IBD patients, as their lifestyles and medications may affect vitamin D levels. Murine studies have added vast amounts to our knowledge of vitamin D and its antimicrobial role, as well as its effect on immune cell proliferation other inflammatory molecules, such as Tumour Necrosis Factor-α (TNFα). It is clear that larger trials investigating the effects of oral supplementation of vitamin D in IBD patients are necessary.

Secondary osteoporosis: pathophysiology & diagnosis

Osteoporosis is a skeletal disease characterized by decreased bone mass and microarchitectural changes in bone tissue that increase the susceptibility to fracture. Secondary osteoporosis is loosely defined as low bone mineral density or increased risk of fragility fracture caused by any factor other than aging or postmenopausal status. The purpose of this review is to discuss the current understanding of the pathophysiology and contribution to fracture risk of many of the more common causes of secondary osteoporosis, as well as diagnostic considerations, outlined by organ system. While not comprehensive, included are a wide array of diseases, conditions, and medications that have been associated with bone loss and susceptibility to fractures. The hope is to highlight the importance to the general clinician of screening for and treating the osteoporosis in these patients, so to limit the resultant increased morbidity associated with fractures.

Glucocorticoid-associated osteoporosis in chronic inflammatory diseases: epidemiology, mechanisms, diagnosis, and treatment

Children with chronic illnesses such as Juvenile Idiopathic Arthritis and Crohn's disease, particularly when taking glucocorticoids, are at significant risk for bone fragility. Furthermore, when childhood illness interferes with achieving normal peak bone mass, life-long fracture risk is increased. Osteopenia and osteoporosis, which is increasingly recognized in pediatric chronic disease, likely results from numerous disease- and treatment-related factors, including glucocorticoid exposure. Diagnosing osteoporosis in childhood is complicated by the limitations of current noninvasive techniques such as DXA, which despite its limitations remains the gold standard. The risk:benefit ratio of treatment is confounded by the potential for spontaneous restitution of bone mass deficits and reshaping of previously fractured vertebral bodies. Bisphosphonates have been used to treat secondary osteoporosis in children, but limited experience and potential long-term toxicity warrant caution in routine use. This article reviews the factors that influence loss of normal bone strength and evidence for effective treatments, in particular in patients with gastrointestinal and rheumatologic disorders who are receiving chronic glucocorticoid therapy.

Serum 25-hydroxyvitamin D concentration and inflammatory bowel disease characteristics in Romania

AIM: To describe the relationship between vitamin D levels and inflammatory bowel disease (IBD) characteristics in northeastern Romanian patients.

METHODS: This was a prospective study of 47 consecutive IBD patients admitted to The Institute of Gastroenterology and Hepatology in Iasi, Romania between March 2011 and June 2012. The diagnosis of IBD was established based on endoscopic, histologic and radiologic findings. Demographic data, disease characteristics, ongoing treatments and biological parameters of patients (including markers of inflammation: C-reactive protein level, fibrinogen level, and erythrocyte sedimentation rate) were recorded. Serum vitamin D levels were measured and compared with age- and sex-matched healthy volunteers from the same geographic area. Vitamin D levels were defined as sufficient (> 30 ng/mL), insufficient (20-30 ng/mL), or severely deficient (< 20 ng/mL).

RESULTS: Thirty-three of the IBD patients included in this study had ulcerative colitis (UC) and 14 had Crohn’s disease (CD). Only 24% of the UC patients and 21% of the CD patients had sufficient vitamin D levels. The vitamin D levels were significantly lower in the CD patients with moderate to severe disease activity compared to the CD patients in remission or with mild disease activity (16 ± 6 ng/mL vs 26 ± 7 ng/mL; 16 ± 6 ng/mL vs 31 ± 9 ng/mL, respectively, P < 0.05). Vitamin D levels in the UC patients were not influenced by disease activity and no correlation was observed with the inflammation markers tested (C-reactive protein, fibrinogen, and erythrocyte sedimentation rate). No association was observed between vitamin D levels and smoking status or ongoing medication (5ASA, steroids, and anti-TNFα). Newly diagnosed IBD patients had lower vitamin D levels than patients with established cases, though these differences were not significant (UC: 22 ± 9 ng/mL vs 26 ± 12 ng/mL; CD: 18 ± 6 ng/mL vs 27 ± 11 ng/mL, respectively). Although no association was found between the season during which the visit was scheduled and vitamin D levels, the UC patients assessed during the winter tended to have lower levels than those assessed during the summer (22 ± 9 ng/mL vs 28 ± 13 ng/mL, respectively).

CONCLUSION: Vitamin D levels are significantly reduced in IBD patients in northeastern Romania, with the lowest levels occurring in CD patients with moderate to severe disease activity.

Review article: vitamin D and inflammatory bowel diseases

BACKGROUND

Vitamin D is traditionally associated with bone metabolism. The immunological effects of vitamin D have increasingly come into focus.

AIM

To review the evidence supporting a role of vitamin D in inflammatory bowel diseases.

METHODS

A comprehensive search was performed on PubMed using the terms 'crohn's disease' 'ulcerative colitis' and 'vitamin D'.

RESULTS

Vitamin D deficiency is common in patients with inflammatory bowel diseases (IBD) (16-95%) including those with recently diagnosed disease. Evidence supports immunological role of vitamin D in IBD. In animal models, deficiency of vitamin D increases susceptibility to dextran sodium sulphate colitis, while 1,25(OH)2 D3 ameliorates such colitis. One prospective cohort study found low predicted vitamin D levels to be associated with an increased risk of Crohn's disease (CD). Limited data also suggest an association between low vitamin D levels and increased disease activity, particularly in CD. In a large cohort, vitamin D deficiency (<20 ng/mL) was associated with increased risk of surgery (OR 1.8, 95% CI 1.2-2.5) in CD and hospitalisations in both CD (OR 2.1, 95% CI 1.6-2.7) and UC (OR 2.3, 95% CI 1.7-3.1). A single randomised controlled trial demonstrated that vitamin D supplementation may be associated with reduced frequency of relapses in patients with CD compared with placebo (13% vs. 29%, P = 0.06).

CONCLUSIONS

There is growing epidemiological evidence to suggest a role for vitamin D deficiency in the development of IBD and also its influence on disease severity. The possible therapeutic role of vitamin D in patients with IBD merits continued investigation.

Vitamin D and Crohn's disease in the adult patient: a review

Crohn's disease (CD) is characterized as a chronic immune-mediated inflammatory disorder of the gastrointestinal tract. Current consensus surrounding the cause of the disease suggests a complex interplay between genetic susceptibility, the intestinal microbiome and environmental factors, leading to the aberrant Th1 and Th17 immune cell mediated response. Vitamin D deficiency is common in CD patients, and long-standing deficiency has been associated with reduced bone mineral density (BMD). Accumulating evidence now suggests that in addition to maintaining skeletal integrity, vitamin D also plays an integral role in regulating the general immune response, a function employed via its genomic actions on the vitamin D receptor (VDR). The VDR is expressed in all immune cells and both directly and indirectly targeted by the bioactive form of vitamin D, 1,25-Dihydroxyvitamin D (1,25[OH]2D). Impaired regulation or deficiency of the vitamin has been linked to the promotion of self-reactive T cell development, loss of immune tolerance to self-structures, and experimental colitis in animal models, whereas the subsequent administration of the vitamin in these models resulted in the improvement of immune-mediated symptoms. In addition, low vitamin D has been associated with disease activity in CD patients, and supplementation appears to be beneficial in improving clinical scores and reducing inflammation. Therefore, the primary aims of this article were to review the molecular evidence supporting the immunoregulatory roles of vitamin D and its supplementation in the CD patient, based on existing literature. The physiological processes, accepted serum concentration values, and its well-recognized role in bone health were also summarized.

Decreased neuromuscular function in Crohn's disease patients is not associated with low serum vitamin D levels

BACKGROUND

Neuromuscular fatigue is a common complaint in Crohn's disease (CD) patients. A correlation between serum vitamin D concentrations and neuromuscular function has been found in the elderly or non-ambulant populations.

AIMS

The aim of this study was to determine whether CD patients exhibit impaired neuromuscular function and if so, is there a link between vitamin D and neuromuscular function.

METHODS

Crohn's disease patients (n = 19) with at least one prior small bowel resection and matched controls (n = 19) underwent muscle strength and endurance testing, vitamin D, and nerve function analysis.

RESULTS

Knee extension and flexion peak torque (Nm/kg) were greater in the control group than in the CD patients (P = 0.04 and 0.014, respectively. A significant difference was found between fatigue rates of the rectus femoris (P = 0.015) between CD patients and controls, but no difference was found in serum vitamin D levels between groups (P = 0.317). Knee extension and flexion torque measurements, with age as a covariate, were compared with high and low vitamin D levels. Those subjects with high serum vitamin D levels had a significantly greater extension peak torque (P = 0.045) and extension average torque (Nm/kg) (P = 0.014) than those with low levels.

CONCLUSION

Crohn's disease patients with sufficient vitamin D levels experienced a 43 % greater extension peak torque. Although vitamin D deficiency has been associated with neuromuscular dysfunction, there were no differences in serum vitamin D levels between the CD and healthy controls to explain the decreased muscle strength.

Vitamin D deficiency in patients with inflammatory bowel disease: association with disease activity and quality of life

BACKGROUND

Vitamin D deficiency is common in inflammatory bowel disease (IBD). The aim of the study was to determine the prevalence and predictors of vitamin D deficiency in an IBD cohort. It was hypothesized that vitamin D deficiency is associated with increased disease activity and lower health-related quality of life (HRQOL).

METHODS

This was a retrospective cohort study. Harvey-Bradshaw index and ulcerative colitis disease activity index were used to assess disease activity. Short Inflammatory Bowel Disease Questionnaire scores were used to assess HRQOL. Multivariate logistic regression was used to identify independent predictors of vitamin D deficiency and its association with disease activity and HRQOL.

RESULTS

The study included 504 IBD patients (403 Crohn's disease [CD] and 101 ulcerative colitis [UC]) who had a mean disease duration of 15.5 years in CD patients and 10.9 years in UC patients; 49.8% were vitamin D deficient, with 10.9% having severe deficiency. Vitamin D deficiency was associated with older age (P = .004) and older age at diagnosis (P = .03). Vitamin D deficiency was associated with lower HRQOL (regression coefficient -2.21, 95% confidence interval [CI], -4.10 to -0.33) in CD but not UC (regression coefficient 0.41, 95% CI, -2.91 to 3.73). Vitamin D deficiency was also associated with increased disease activity in CD (regression coefficient 1.07, 95% CI, 0.43 to 1.71).

CONCLUSIONS

Vitamin D deficiency is common in IBD and is independently associated with lower HRQOL and greater disease activity in CD. There is a need for prospective studies to assess this correlation and examine the impact of vitamin D supplementation on disease course.

Assessment and management of low bone density in inflammatory bowel disease and performance of professional society guidelines

BACKGROUND

Inflammatory bowel disease (IBD) patients have increased prevalence of osteoporosis, leading to guideline recommendations for bone mineral density (BMD) testing. The study aim was to identify predictors of BMD testing and treatment and assess guideline effectiveness to identify IBD patients with osteoporosis.

METHODS

Records of all IBD patients at seven medical facilities were reviewed for clinical data and BMD testing from January 1996 through October 2006.

RESULTS

A total of 2035 patients had 317 bone density tests performed. Osteopenia was found in 48% of patients, osteoporosis in 26%. Among patients meeting guideline criteria for BMD testing and ≥1 year of follow-up, 23.3% underwent testing. The strongest predictors of testing were menopause (adjusted hazard ratio [AHR] 3.02) and receiving care at a tertiary center (AHR 2.56). Testing rates were low in patients with age ≥60 years, ulcerative colitis, and a history of inpatient IBD treatment. Osteoporotic patients received calcium/vitamin D and bisphosphonates in 59% and 75% of cases, respectively. Osteoporotic males had a 37% rate of hypogonadism. Guideline criteria do not distinguish patients with osteoporosis. The criteria had a sensitivity, specificity, positive predictive value, and negative predictive value of 84%, 23%, 27%, and 81% for osteoporosis in the tested population, respectively.

CONCLUSIONS

Osteoporosis is highly prevalent in the IBD population, but BMD testing and osteoporosis treatments are underutilized. Male hypogonadism is common in osteoporotic IBD patients. Guidelines do not identify IBD patients with osteoporosis.

Review article: the effects of antitumour necrosis factor-α on bone metabolism in inflammatory bowel disease

BACKGROUND

Patients with inflammatory bowel disease (IBD) are at increased risk of osteoporosis. A number of studies have emerged in recent years indicating that tumour necrosis factor (TNF) blockade appears to have a beneficial effect on bone mineral density (BMD) in IBD patients.

AIMS

To provide a review of the available data regarding the effect of the currently licensed anti-TNF-α therapies on bone metabolism and BMD in IBD patients.

METHODS

A Medline search was performed using the search terms 'infliximab', 'bone metabolism', 'IBD', 'BMD', 'bone markers', 'adalimumab', 'bone disease', 'Crohn's disease' and 'ulcerative colitis'.

RESULTS

Infliximab has a beneficial effect on bone turnover markers in Crohn's disease (CD) patients in the short term. The longest study to date comprising 24 CD patients showed an overall improvement in two bone formation markers - b-alkaline phosphatase (P = 0.022) and osteocalcin (P = 0.008) at 4 months post-treatment. Moreover, the largest study to date comprising 71 CD patients showed significant improvement in sCTx, a bone resorption marker (P = 0.04) at week-8 post-treatment. There is little data looking at the effect of anti-TNF-α therapy on bone metabolism in ulcerative colitis. Moreover, the long-term effects of anti-TNF-α therapy on bone structure and fracture risk in IBD patients are currently not known. The effect of cessation of anti-TNF-α therapy on bone metabolism is also unknown.

CONCLUSION

Properly controlled long-term trials are needed to fully evaluate the impact of TNF blockade on bone mineral density.

Vitamin D and inflammation

Calcitriol, or 1,25-dihydroxyvitamin D3 (1,25(OH)(2)D3) is a well-known endocrine regulator of calcium homeostasis. More recently, local calcitriol production by immune cells was shown to exert autocrine or paracrine immunomodulating effects. Immune cells that produce calcitriol also express the vitamin D receptor (VDR) and the enzymes needed to metabolize vitamin D3 (1α-, 25-, and 24-hydroxylases). Studies of animal models and cell cultures showed both direct and indirect immunomodulating effects involving the T cells, B cells, and antigen-presenting cells (dendritic cells and macrophages) and affecting both innate and adaptive immune responses. The overall effect is a switch from the Th1/Th17 response to the Th2/Treg profile. The immunomodulating effects of vitamin D may explain the reported epidemiological associations between vitamin D status and a large number of autoimmune and inflammatory diseases. Such associations have been suggested by observational studies not only in rheumatoid arthritis, lupus, inflammatory bowel disease, and type 1 diabetes; but also in infections, malignancies, transplant rejection, and cardiovascular disease. In animal models for these diseases, vitamin D supplementation has been found to produce therapeutic effects. Thus, vitamin D is a key focus for public health efforts and may hold promise for the treatment of dysimmune diseases.

IL-6 may modulate the skeletal response to glucocorticoids during exacerbations of inflammatory bowel disease

Whether inflammatory cytokines affect the skeletal response to glucocorticoid (GC) treatment is unclear. Our objectives were to (1) identify the cytokine(s) elevated during exacerbations of inflammatory bowel disease (IBD); (2) determine whether the cytokine(s) identified in this way is related to systemic GC sensitivity; and (3) examine whether cytokines and/or measures of GC sensitivity are related to changes in bone formation or resorption following GC therapy. We designed a combined cross-sectional and prospective study, including patients with active (n = 31) and inactive (n = 34) IBD as well as controls (n = 29). We assessed circulating concentrations of cytokines, PINP and betaCTX, as well as GC sensitivity in peripheral blood mononuclear cells. IL-6 was the only cytokine increased in active IBD, 2.35 (2.63) versus 1.64 (1.21) versus 1.31 (2.79) pg/microl active IBD, inactive IBD, and controls, respectively (median [interquartile range]) (P = 0.03, ANOVA). IL-6 was positively related to magnitude of GC sensitivity (beta = 0.02, 95% CI 0.008-0.04, P = 0.005). Following treatment with GC in active IBD, PINP decreased (P < 0.001), whereas betaCTX showed no significant change (P = 0.2). Subsequently, multiple regression analyses revealed that plasma IL-6 concentrations were inversely related to the extent of PINP suppression following GC (beta = 3.3, 95% CI 0.2-6.4, P = 0.04, adjusted for baseline PINP and duration of GC treatment), while no association was observed with GC sensitivity. In conclusion, IL-6 is elevated in active IBD and may protect against GC-induced suppression of bone formation via a mechanism which appears to be independent of systemic GC sensitivity.

Use of risedronate to prevent bone loss following a single course of glucocorticoids: findings from a proof-of-concept study in inflammatory bowel disease

SUMMARY

We performed a randomised controlled trial (RCT) to determine whether risedronate 35 mg once weekly prevents bone loss following an 8-week reducing course of prednisolone given for an exacerbation of inflammatory bowel disease (IBD). The greatest change in bone mineral density (BMD) was at Ward's triangle (WT), which fell by 2.2% in the placebo group, compared with a reduction of 0.8% in the risedronate group.

INTRODUCTION

Whether bisphosphonates can prevent bone loss associated with intermittent glucocorticoid (GC) therapy is unknown, reflecting the difficulty in performing RCTs in this context.

METHOD

To explore the feasibility of RCTs to examine this question, lumbar spine (LS; L2-4) and hip dual X-ray absorptiometry (DXA) scans were performed in 78 patients commencing a GC therapy course for a relapse of IBD. They were then randomised to receive placebo or risedronate 35 mg weekly for 8 weeks, after which the DXA scan was repeated.

RESULTS

For LS BMD, there was no change in the placebo group (0.1 +/- 0.4, p = 0.9), but there was an increase after risedronate (0.8 +/- 0.4, p = 0.04; mean% +/- SEM by paired Student's t test). There were small decreases in both groups at the total hip (-0.5 +/- 0.3, p = 0.04; -0.5 +/- 0.3, p < 0.05, placebo and risedronate, respectively). At WT, BMD fell after placebo (-2.2 +/- 0.5, p = 0.001) but not risedronate (-0.8 +/- 0.5, p = 0.09; p = 0.05 for between-group comparison).

CONCLUSION

RCTs can be used to examine whether bisphosphonates prevent bone loss associated with intermittent GC therapy, providing metabolically active sites such as WT are employed as the primary outcome.

[Low levels of 25-hydroxyvitamin D (25OHD) in patients with inflammatory bowel disease and its correlation with bone mineral density]

Patients with inflammatory bowel disease (IBD) are at risk of having vitamin D deficiency (25-OHD) and low bone mineral density (BMD).

OBJECTIVES

To measure 25OHD in a young group of IBD patients submitted to a clinical evaluation, routine biochemistry and BMD measurement (lumbar spine and proximal femur).

RESULTS

39 Crohn disease (CD) and 37 ulcerative colitis (UC) patients had lower serum levels of 25OHD compared to the control group (CD p = 0.003; UC p < 0.001), and 48.5% of the UC patients were 25OHD deficient. Lumbar spine BMD was lower in patients than controls (CD p = 0.001; UC p = 0.008). In CD patients, serum levels of 25OHD were significantly correlated with total femur (r = 0.391; p = 0.027) and femoral neck (r = 0.384; p = 0.03) BMD.

CONCLUSION

It was found lower levels of 25OHD and BMD in young IBD patients compared to normal controls, suggesting an important role of 25OHD deficiency in the pathogenesis of the IBD bone disease.

The effect of melanism and vitamin D synthesis on the incidence of autoimmune disease

Melanin has several physiological roles in maintaining health, but, notably, it affects the synthesis of vitamin D. Melanin is the primary determinant of the degree of skin pigmentation and protects the body from harmful ultraviolet radiation. Synthesis of 1,25-dihydroxyvitamin D(3) (1,25[OH](2)D(3)) in the skin, however, is dependent on ultraviolet B light. Highly pigmented skin, to the level found in people of African origin, abrogates almost all ultraviolet-induced 1,25(OH)(2)D(3) synthesis. Numerous animal models and clinical studies have underlined the essential role of vitamin D as a modulator of the different processes of the immune system. Evidence indicates that serum concentrations of 1,25(OH)(2)D(3) and the prevalence of autoimmune diseases in a certain population are associated with the latitude at which that population resides. This article explores the relationship between skin pigmentation, vitamin D and the prevalence of autoimmune disease.

Extraintestinal manifestations of inflammatory bowel disease

The idiopathic inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis, may be complicated by extraintestinal manifestations (EIMs) in up to 40% of patients. Reports suggest that almost every organ system may be affected. The EIMs are a significant cause of morbidity and may be particularly distressing for the patient. Recent attempts have been made to define the phenotype of IBD in patients of different ethnicities. These studies have highlighted potential racial variations in the prevalence of specific EIMs, findings that are perhaps not surprising given the influence of genetic factors in their pathogenesis. Certain EIMs are related to the activity of the bowel disease, and their management often involves careful monitoring while the IBD is brought under control. Other EIMs, however, typically run a course independent of the IBD activity, and specific, targeted treatments may be required, even including biologic agents such as infliximab.

Dual-energy X-ray aborptiometry assessment in children and adolescents with diseases that may affect the skeleton: the 2007 ISCD Pediatric Official Positions

The Task Force focusing on the use of dual energy X-ray absorptiometry (DXA) in children and adolescents with diseases that may affect the skeleton reviewed over 300 articles to establish the basis for the Official Positions. A significant number of studies used DXA-based outcome measures to assess the effects of specific interventions and charted the natural history of incremental changes in bone size and mass in specific disease states in children. However, the utility of DXA in clinical practice has not been evaluated systematically, in large part due to the lack of a workable definition for childhood osteoporosis. Thus, in combination with the Official Positions addressing the diagnosis of osteoporosis in children, and the reporting of DXA results in children, this document presents clear guidelines from which clinicians and researchers alike can work. This report delineates a set of disorders in which it is appropriate to use DXA as part of the comprehensive assessment of skeletal health in children and adolescents, and provides guidance concerning the initiation of assessment and the frequency of monitoring. Importantly, this document also highlights significant gaps in our knowledge, emphasizing areas for future research.

Novel role of the vitamin D receptor in maintaining the integrity of the intestinal mucosal barrier

Emerging evidence supports a pathological link between vitamin D deficiency and the risk of inflammatory bowel disease (IBD). To explore the mechanism we used the dextran sulfate sodium (DSS)-induced colitis model to investigate the role of the vitamin D receptor (VDR) in mucosal barrier homeostasis. While VDR(+/+) mice were mostly resistant to 2.5% DSS, VDR(-/-) mice developed severe diarrhea, rectal bleeding, and marked body weight loss, leading to death in 2 wk. Histological examination revealed extensive ulceration and impaired wound healing in the colonic epithelium of DSS-treated VDR(-/-) mice. Severe ulceration in VDR(-/-) mice was preceded by a greater loss of intestinal transepithelial electric resistance (TER) compared with VDR(+/+) mice. Confocal and electron microscopy (EM) revealed severe disruption in epithelial junctions in VDR(-/-) mice after 3-day DSS treatment. Therefore, VDR(-/-) mice were much more susceptible to DSS-induced mucosal injury than VDR(+/+) mice. In cell cultures, 1,25-dihydroxy-vitamin D(3) [1,25(OH)(2)D(3)] markedly enhanced tight junctions formed by Caco-2 monolayers by increasing junction protein expression and TER and preserved the structural integrity of tight junctions in the presence of DSS. VDR knockdown with small interfering (si)RNA reduced the junction proteins and TER in Caco-2 monolayers. 1,25(OH)(2)D(3) can also stimulate epithelial cell migration in vitro. These observations suggest that VDR plays a critical role in mucosal barrier homeostasis by preserving the integrity of junction complexes and the healing capacity of the colonic epithelium. Therefore, vitamin D deficiency may compromise the mucosal barrier, leading to increased susceptibility to mucosal damage and increased risk of IBD.

Changes of OPG and RANKL concentrations in Crohn's disease after infliximab therapy

BACKGROUND

Osteoporosis is a well-known complication of Crohn's disease (CD). Osteoprotegerin (OPG) concentration is elevated in patients with CD compared to healthy controls. Long-term infliximab (IFX) maintenance therapy improves the patients' bone mineral density. The effect of IFX on bone metabolism has not yet been clarified. Our aim was to evaluate IFX effects on bone pathology in CD patients.

METHODS

Twenty-nine patients were treated with IFX as an induction therapy according to international guidelines at weeks 0, 2, and 6. Serum concentrations of biochemical markers of bone formation (osteocalcin, OC) and bone resorption (beta-crosslaps, bCL), and serum concentrations of OPG and receptor activator of nuclear factor kappa B ligand (sRANKL) were measured before every treatment at days 1, 14, and 42.

RESULTS

Serum levels of OC and sRANKL increased after treatment. OC concentrations were 28.93 +/- 14.95 ng/mL versus 36.33 +/- 20.05 ng/mL (P < 0.005) at days 1 and 42, respectively; sRANKL concentrations were elevated from 0.0112 +/- 0.028 ng/mL to 0.0411 +/- 0.123 ng/mL (NS) by the end of the study. The concentrations of both bCL and OPG decreased. bCL concentrations were 0.636 +/- 0.594 versus 0.519 +/- 0.235 (NS) at days 1 and 42, respectively, while OPG concentration decreased from 3.739 +/- 1.485 to 3.491 +/- 1.618 (P < 0,05).

CONCLUSIONS

IFX therapy decreased the OPG concentration in CD patients significantly. In parallel, the serum bone resorption marker (bCL) also decreased. Concentrations of bone formation marker (OC) and sRANKL increased during the same period; however, those changes were not statistically significant. Elevated OPG in CD could be a counter-regulatory response to inflammatory cytokines or may reflect T-cell activation.

Skeletal muscle wastage in Crohn's disease: a pathway shared with heart failure?

BACKGROUND

Lean body mass wastage in active Crohn's disease is not only related to malnutrition, but also to local and systemic inflammation. Altered bowel permeability can represent a source of pro-inflammatory cytokines, that have been shown to produce muscle wastage by several mechanisms such as apoptosis. In our study we have evaluated the body composition and the pathological changes of skeletal muscle in patients with Crohn's disease to see whether a relationships between altered gut permeability, proinflammatory cytokines production and muscle wastage existed.

METHODS

Thirteen consecutive steroid-free patients with active Crohn's disease underwent evaluation of body composition, sugar test for intestinal permeability, determination of serum levels of TNF-alpha, sphingosine, bacterial lipopolysaccaride, and biopsy of gastrocnemius. In bioptic samples we determined fibres cross sectional area, distribution of myosin heavy chains and apoptosis. Twenty healthy subjects formed the control group.

RESULTS

In patients lean body mass was reduced and intestinal permeability increased (p<0.01 for both). TNFalpha, sphingosine and lipopolysaccaride were increased (p<0.01). Fibres size was reduced (p<0.01), with shift of Myosin Heavy Chains from the slow to the fast type. Apoptosis was found in 5 patients' biopsies, never in controls.

CONCLUSIONS

Crohn's patients have a myopathy characterized by myocyte apoptosis, modifications of myosin and muscle atrophy. TNF-alpha and sphingosine, that are increased because of the enhanced lipopolysaccaride concentration due to altered gut permeability, may play a pathophysiological role in the development of this myopathy.

Vitamin D and its implications for musculoskeletal health in women: an update

Vitamin D is a hormone that controls phosphorus, calcium, and bone metabolism and neuromuscular function. Vitamin D synthesis is a process in which the skin, liver, and kidney are sequentially involved. The vitamin D pool is completed by the amount taken with food and supplements. Vitamin D deficiency causes osteopenia, precipitates and exacerbates osteoporosis, causes a painful disease, osteomalacia, and increases muscle weakness, which worsens the risk of falls and fractures. A high prevalence of vitamin D insufficiency exists in the apparently healthy population, osteoporotic patients, and patients with prior fractures. Factors contributing to low vitamin D levels include low sunlight exposure, decreased skin synthesis and intestinal absorption, and inadequate diet. The simplest way to correct hypovitaminosis is adequate nutrition and supplements. However, few patients with osteoporosis and/or fractures, receive adequate supplements. Vitamin D insufficiency may alter the regulatory mechanisms of parathyroid hormone and may induce a secondary hyperparathyroidism that increases the risk of osteoporosis and fractures, although the necessary degree of this is not established. Monitoring of serum 25-hydroxyvitamin D levels is the only way to assess vitamin D status. The ideal healthy blood levels of 25-hydroxyvitamin D are controversial, although a range from 30 to 60ng/mL is widely accepted. The role of vitamin D supplementation is to provide humans with the nutrient in an amount closer to the biological norm for our species. This amount of vitamin D results in optimal function of many aspects of health, including balance and muscle strength, thus reducing the risk of fracture beyond what is possible via the quality and quantity of bone itself.

Vitamin D and autoimmunity: new aetiological and therapeutic considerations

Vitamin D is frequently prescribed by rheumatologists to prevent and treat osteoporosis. Several observations have shown that vitamin D inhibits proinflammatory processes by suppressing the enhanced activity of immune cells that take part in the autoimmune reaction. Moreover, recent evidence strongly suggests that vitamin D supplementation may be therapeutically beneficial, particularly for Th1-mediated autoimmune disorders. Some reports imply that vitamin D may even be preventive in certain disorders such as multiple sclerosis and diabetes type 1. It seems that vitamin D has crossed the boundaries of calcium metabolism and has become a significant factor in a number of physiological functions, specifically as a biological inhibitor of inflammatory hyperactivity.

Report on the vitamin D status of adult and pediatric patients with inflammatory bowel disease and its significance for bone health and disease

Vitamin D is a hormone responsible for calcium homeostasis and essential for bone mineralization throughout the lifespan. Recent studies revealed a high prevalence of hypovitaminosis D among healthy adults and children, especially in the northern hemisphere, and a link between this condition and suboptimal bone health. Moreover, maintenance of what are today considered optimal vitamin D stores has not been achieved throughout the year with currently recommended daily intake for vitamin D. The prevalence of hypovitaminosis D is even higher among adults with inflammatory bowel disease (IBD), a situation that may be caused by malabsorption and gastrointestinal losses through an inflamed intestine, among other factors. In children with IBD, existing reports of vitamin D status are scarce. The relationship between vitamin D status and bone health, although well-established in healthy adults and children, has been controversial among adults and children with IBD, and the reasons for this have not been investigated to date. Studies in animal models of colitis and in vitro human studies support a role of vitamin D in the regulation of the immune system of the gut and the potential of vitamin D and its derivatives as therapeutic adjuncts in the treatment of IBD. This role of vitamin D has not been investigated with translational studies to date. Currently, there are no guidelines for monitoring vitamin D status, treating hypovitaminosis D, and maintaining optimal vitamin D stores in patients with IBD. These tasks may prove particularly difficult because of malabsorption and gastrointestinal losses that are associated with IBD.

Bone mineral density in Iranian patients with inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) are at increased risk of developing osteopenia and osteoporosis. The aim of the study was to investigate the prevalence of decreased bone density and related risk factors in Iranian IBD patients. A total of 126 ulcerative colitis (UC) and 39 Crohn's disease (CD) patients were enrolled. Dual-energy x-ray absorptiometry technique was used to measure bone density, and blood samples were obtained to measure biochemical markers. To find predictive variables for bone mineral density (BMD), stepwise regression analysis was carried out. A total of 53 IBD patients (32.1%) had diminished bone mineral density at either lumbar spine (L1-L4) or femoral neck. Of these, 9 (5.4%) had osteoporosis; however, 44 (26.7%) were osteopenic. Femoral neck bone density was significantly decreased among CD patients (p<0.04). There was no significant difference in BMD between men and women. We have found significant differences in BMD T scores at lumbar L1-L4, L2-L4, and femoral neck in corticosteroid ever-users (p<0.002, p<0.001, p<0.003, respectively). There was no significant difference in biochemical markers between UC and CD patients, except that more CD patients were hypocalcemic (p<0.001). Stepwise regression analysis has revealed lumbar spine T score was predicted by age (p<0.0001), corticosteroid use (p<0.002), and body mass index (BMI) (p<0.005); however, femoral neck was predicted by age (p<0.0001), BMI (p<0.0001), smoking (p<0.009), and corticosteroid use (p<0.028). Low bone density in Iranian UC and CD patients is in accordance with Western societies. Treatment with corticosteroid has increased this possibility in both groups. Corticosteroid use, age, smoking, and BMI are predictive factors for low bone density.

Vitamin D status in children and young adults with inflammatory bowel disease

OBJECTIVES

Previous studies of vitamin D status in pediatric patients with inflammatory bowel disease have revealed conflicting results. We sought to report (1) the prevalence of vitamin D deficiency (serum 25-hydroxy-vitamin D concentration < or = 15 ng/mL) in a large population with inflammatory bowel disease, (2) factors predisposing to this problem, and (3) its relationship to bone health and serum parathyroid hormone concentration.

PATIENTS AND METHODS

A total of 130 patients (8-22 years of age) with inflammatory bowel disease, 94 with Crohn disease and 36 with ulcerative colitis, had serum 25-hydroxy-vitamin D, intact parathyroid hormone, and lumbar spine bone mineral density (using dual-energy x-ray absorptiometry) measured at Children's Hospital Boston.

RESULTS

The prevalence of vitamin D deficiency was 34.6%. Mean serum 25-hydroxy-vitamin D concentration was similar in patients with Crohn disease and ulcerative colitis, 52.6% lower among patients with dark skin complexion, 33.4% lower during the winter months (December 22 to March 21), and 31.5% higher among patients who were taking vitamin D supplements. Serum 25-hydroxy-vitamin D concentration was positively correlated with weight and BMI z score, disease duration, and serum albumin concentration and negatively correlated with erythrocyte sedimentation rate. Patients with Crohn disease and upper gastrointestinal tract involvement were more likely to be vitamin D deficient than those without it. Serum 25-hydroxy-vitamin concentration was not associated with lumbar spine bone mineral density z score or serum parathyroid hormone concentration.

CONCLUSIONS

Vitamin D deficiency is highly prevalent among pediatric patients with inflammatory bowel disease. Factors predisposing to the problem include having a dark-skin complexion, winter season, lack of vitamin D supplementation, early stage of disease, more severe disease, and upper gastrointestinal tract involvement in patients with Crohn disease. The long-term significance of hypovitaminosis D for this population is unknown at present and merits additional study.

Prevention and treatment of osteoporosis in inflammatory bowel disease

The following are guidelines for evaluation and consideration for treatment of patients with inflammatory bone disease (IBD) after bone mineral density (BMD) measurements. The Crohn's & Colitis Foundation of America (CCFA) has indicated that its recommendations are intended to serve as reference points for clinical decision-making, not as rigid standards, limits, or rules. They should not be interpreted as quality standards.

Bone density in young males with recently diagnosed inflammatory bowel disease

OBJECTIVES

Patients with inflammatory bowel disease are at increased risk of developing osteopenia and osteoporosis. Our study was designed to determine the degree of decreased bone density in steroid naïve young male patients with inflammatory bowel disease and to unmask possible risk factors.

METHODS

Before the initiation of any treatment in young male patients aged 26 +/- 4.8 years with inflammatory bowel disease, ultrasound bone density measurement at the right calcaneous was performed using a Lunar Achilles plus device. Stiffness Index and T-score were measured. We also performed an ultrasound bone density measurement at right calcaneous in healthy age- and sex-matched controls.

RESULTS

Nine out of 32 patients with inflammatory bowel disease had osteopenia or osteoporosis (approximately 28%). Of controls, two individuals had osteopenia (approximately 7%). There was a positive correlation between T-score and body mass index, but not between T-score and age in patients with inflammatory bowel disease. There was a statistically significant difference in T-score between patients with disease duration>6 months and those with disease duration<6 months (P=0.032), but not between the patients with Crohn's disease compared with the patients with ulcerative colitis.

CONCLUSION

Steroid naïve young male patients with inflammatory bowel disease have lower bone density values than healthy controls. According to our findings, duration of disease above 6 months and low body mass index are major risk factors for low bone density in these patients. Bone density measurement should be performed in all patients with inflammatory bowel disease in an early stage of the disease.

Mechanisms of disease: vitamin D and inflammatory bowel disease

Until recently, 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3))-the active form of vitamin D-was thought to function primarily as a regulator of calcium and phosphate metabolism. More diverse functionality was indicated by the discovery of the vitamin D receptor in tissues that are not involved in calcium and phosphate homeostasis. Detection of the vitamin D receptor in monocytes and activated T cells has sparked interest in the immunomodulatory properties of vitamin D. Here, we review the role of vitamin D in regulation of the immune system, and evidence for its involvement in the pathogenesis of inflammatory bowel disease.

Efficacy of risedronate administration in osteoporotic postmenopausal women affected by inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) have frequently a bone mineral density (BMD) significantly lower than age-matched healthy subjects. The low BMD observed in IBD patients is related also to a higher incidence of bone fractures. In this prospective randomized study we evaluated the effect of 1-year risedronate administration on bone mass and turnover, and on vertebral fractures in osteoporotic postmenopausal women with IBD in remission. Ninety osteoporotic postmenopausal women were randomized to receive oral risedronate 35 mg/week (risedronate group) or placebo tablets (placebo group; one tab/week). The duration of treatment was 12 months. At entry and after treatment, lumbar spine and hip BMD, and serum osteocalcin (OC) and urinary deoxypyridinoline/creatinine ratio (DPD-Cr) levels were evaluated. Vertebral fractures were assessed from thoracic and lumbar lateral and anterior-posterior spinal radiographs taken at baseline, and from lateral spinal radiographs taken at the end of the study. At study entry, no difference between groups was also detected in BMD and in bone turnover markers. At the end of the study, lumbar spine, trochanter and femoral neck BMD was significantly ( p <0.05) higher in comparison with baseline in the risedronate group, whereas a significant ( p <0.05) decrease was observed in the placebo group. For the same visit, a significant ( p <0.05) difference in lumbar spine, trochanter and femoral neck BMD was detected between groups. After 12-month follow-up, serum OC and urinary DPD-Cr levels were significantly ( p <0.05) lower and higher in comparison with basal values in risedronate and placebo group, respectively. At the same time, a significant ( p <0.05) difference in serum OC and urinary DPD-Cr levels was observed between groups. Throughout the study, the incidence of vertebral fractures was significantly ( p <0.05) lower in the risedronate group than in the placebo group (12.5% vs 34.1%). The relative risk (RR) to develop a new vertebral fracture after 1 year of risedronate administration was of 0.36 (95% confidence interval, 0.14-0.85). In conclusion, risedronate administration is an effective anti-osteoporotic treatment in osteoporotic postmenopausal women with IBD in remission.

Transforming growth factor beta1 and prostaglandin E2 concentrations are associated with bone formation markers in ulcerative colitis patients

Osteoporosis is a significant complication of a multifactoral etiology associated with inflammatory bowel disease. The aim of study was to evaluate the relationships between bone mineral density as well as bone turnover markers and inflammatory activity modulators (i.e., PGE2 and TGFbeta1) in ulcerative colitis (UC). Twenty-one active ulcerative colitis subjects and 14 healthy individuals were included into the study. We observed no significant differences in serum concentrations of osteoprotegerin and osteocalcin, as well as bone mineral density between UC patients and healthy individuals. Plasma concentrations of PGE2, TGFbeta1 and TNF-alpha were significantly higher in UC patients than in controls. Serum osteocalcin demonstrated a positive correlation with both serum PGE2 and plasma TGFbeta1. Moreover there was significant correlation between osteoprotegerin and TGFbeta1 as well as serum TNF-alpha concentrations. In conclusion a positive association between PGE2 and TGFbeta1 and bone formation markers-osteoprotegerin and osteocalcin, as well as a comparable BMD in UC patients and healthy individuals was shown. Our results may indicate that increase of PGE2 as well as TGFbeta1 concentrations may play a protective role against bone loss in ulcerative colitis patients.

Vitamin D and the elderly

This review summarizes current knowledge on vitamin D status in the elderly with special attention to definition and prevalence of vitamin D insufficiency and deficiency, relationships between vitamin D status and various diseases common in the elderly, and the effects of intervention with vitamin D or vitamin D and calcium. Individual vitamin D status is usually estimated by measuring plasma 25-hydroxyvitamin D (25OHD) levels. However, reference values from normal populations are not applicable for the definition of vitamin D insufficiency or deficiency. Instead vitamin D insufficiency is defined as the lowest threshold value for plasma 25OHD (around 50 nmol/l) that prevents secondary hyperparathyroidism, increased bone turnover, bone mineral loss, or seasonal variations in plasma PTH. Vitamin D deficiency is defined as values below 25 nmol/l. Using these definitions vitamin D deficiency is common among community-dwelling elderly in the developed countries at higher latitudes and very common among institutionalized elderly, geriatric patients and patients with hip fractures. Vitamin D deficiency is an established risk factor for osteoporosis, falls and fractures. Clinical trials have demonstrated that 800 IU (20 microg) per day of vitamin D in combination with 1200 mg calcium effectively reduces the risk of falls and fractures in institutionalized patients. Furthermore, 400 IU (10 microg) per day in combination with 1000 mg calcium or 100 000 IU orally every fourth month without calcium reduces fracture risk in individuals over 65 years of age living at home. Yearly injections of vitamin D seem to have no effect on fracture risk probably because of reduced bioavailability. Simulation studies suggest that fortification of food cannot provide sufficient vitamin D to the elderly without exceeding present conventional safety levels for children. A combination of fortification and individual supplementation is proposed. It is argued that all official programmes should be evaluated scientifically. Epidemiological studies suggest that vitamin D insufficiency is related to a number of other disorders frequently observed among the elderly, such as breast, prostate and colon cancers, type 2 diabetes, and cardiovascular disorders including hypertension. However, apart from hypertension, causality has not been established through randomized intervention studies. It seems that 800 IU (20 microg) vitamin D per day in combination with calcium reduces systolic blood pressure in elderly women.

Rapid hip bone loss in active Crohn's disease patients receiving short-term corticosteroid therapy

BACKGROUND

Uncertainty over whether corticosteroids cause bone loss in patients with Crohn's disease may reflect their short, intermittent use.

AIM

We investigated whether a 2-month course of prednisolone is associated with detectable bone loss.

METHODS

Fifteen patients with active Crohn's disease and 19 controls with inactive Crohn's disease were recruited. Bone mineral density of the lumbar spine and hip was measured at baseline and 2 and 8 months.

RESULTS

At 2 months, significant bone loss was found in patients with active disease (femoral neck -2.7%, P < 0.002; Ward's triangle -3.9%, P < 0.01). Although bone mineral density was still lower at 8 months, these differences were no longer significant (-1.3% and -3.4%, femoral neck and Ward's triangle, respectively). No significant change in hip bone mineral density was observed in controls. Previous corticosteroid use was not significantly associated with baseline bone mineral density, although significant independent associations were observed between weight, site of disease and lumbar spine bone mineral density, and between dietary calcium deficiency and femoral neck and Ward's triangle bone mineral density.

CONCLUSION

Significant bone loss at the hip can be detected in patients receiving corticosteroid treatment for 2 months for active Crohn's disease ; however, it remains unclear whether this is because of disease activity or its treatment. This rapid bone loss may represent a risk factor for fracture and justify bone protective therapy.

Effect of antitumour necrosis factor-alpha therapy on bone turnover in patients with active Crohn's disease: a prospective study

BACKGROUND AND AIMS

Patients with Crohn's disease are at increased risk of osteoporosis. Disease activity and circulating proinflammatory cytokines are thought to play a role in this process. Infliximab, a chimaeric antitumour necrosis factor-alpha antibody is effective in the treatment of Crohn's disease. The aim of this study was to investigate the impact of treatment with infliximab on bone turnover in Crohn's disease patients.

METHODS

This was a prospective trial. Twenty-four patients with active Crohn's disease were treated with infliximab (5 mg/kg). Bone markers were assayed pre- and post-treatment. Bone formation was measured using serum bone-specific alkaline phosphatase and total osteocalcin and bone resorption using serum N-telopeptide cross-linked type 1 collagen.

RESULTS

Infliximab therapy caused a significant increase in both markers of bone formation in patients with active Crohn's disease. No significant change in the bone resorption marker serum N-telopeptide cross-linked type 1 was found.

CONCLUSION

Infliximab therapy had a significant beneficial effect on bone metabolism in patients with active Crohn's disease. These findings further support the theory that active ongoing inflammation and high levels of circulating cytokines play a pivotal role in the pathogenesis of bone loss in patients with Crohn's disease.

Laboratory markers predict bone loss in Crohn's disease: relationship to blood mononuclear cell function and nutritional status

BACKGROUND

Crohn's disease is associated with reduced bone density. The power of simple markers of systemic inflammation to identify higher rates of bone loss, in Crohn's disease, is uncertain. This relationship and the role of circulating (peripheral blood) mononuclear cells were investigated in a case-control study.

METHODS

Urinary deoxypyridinoline/creatinine and serum osteocalcin concentrations were compared in male and premenopausal females with "active" Crohn's disease (C-reactive protein > or = 10 and/or erythrocyte sedimentation rate > or = 20) (n = 22) and controls with "quiescent" Crohn's disease (C-reactive protein < 10 and erythrocyte sedimentation rate < 20) (n = 21). No patients were receiving corticosteroid therapy. Production of tumour necrosis factor-alpha, interferon-gamma and prostaglandin E(2) by peripheral blood mononuclear cells were measured.

RESULTS

Active Crohn's disease was associated with a higher deoxypyridinoline/creatinine (P = 0.02) and deoxypyridinoline/creatinine:osteocalcin ratio (P =0.01) compared with quiescent Crohn's disease, but similar osteocalcin (P = 0.24). These were not explained by vitamin D status, dietary intake or nutritional status. However, production of interferon-gamma by concanavalin A-stimulated peripheral blood mononuclear cells was lower in active Crohn's disease (P = 0.02) and correlated negatively with the deoxypyridinoline/creatinine:osteocalcin ratio (r = -0.40, P = 0.004).

CONCLUSION

In Crohn's disease, raised C-reactive protein and erythrocyte sedimentation rate may indicate higher rates of bone loss and, if persistent, the need to assess bone mass even where disease symptoms are mild. This may be partly explained by altered production of interferon-gamma by peripheral blood mononuclear cells.

Extraintestinal complications of inflammatory bowel disease

Recent studies of extraintestinal manifestations (EIMs) of inflammatory bowel disease (IBD) have demonstrated the importance of genetic predisposition in the etiology of musculoskeletal and cutaneous manifestations. In addition, small studies have shown infliximab to be effective in treating troublesome EIMs, particularly in pyoderma gangrenosum. Other trials have examined the safety of cyclooxygenase-2-specific nonsteroidal inflammatory drugs in IBD. Further work has been done on osteoporosis in IBD, and the American Gastroenterological Association has published a technical review and management guidelines for osteoporosis in a range of gastrointestinal disorders. However, despite further publications, debate remains concerning whether IBD patients with osteoporosis have a significant increase in fracture risk, and whether the bone loss is related to the disease or to its treatment.

Bone mineral density in patients with inflammatory bowel disease: a population-based prospective two-year follow-up study

BACKGROUND

Bone loss and osteoporosis are commonly reported in inflammatory bowel disease (IBD), especially Crohn disease (CD). The aims of the present study were to evaluate changes in bone mineral density (BMD) in IBD patients during a 2-year follow-up period, and to investigate the role played by possible contributing factors in bone loss.

METHODS

Sixty patients with CD and 60 with ulcerative colitis (UC) were studied initially. Fifty-five CD and 43 UC patients were re-examined after 1 year, and 50 CD and 44 UC patients after 2 years. Lumbar spine, femoral neck and total body BMD were measured by dual X-ray absorptiometry (DXA), and Z scores were obtained by comparison with age-matched and sex-matched healthy subjects. Biochemical variables were assessed at inclusion and at the 1-year follow-up visit.

RESULTS

Mean BMD values were unchanged in both CD and UC patients. In patients with repeated measurements, significant differences in Z scores (delta Z score) were found for femoral neck and total body in CD and for total body in UC. Significant bone loss occurred in 11 CD (22%) and 12 UC (27%) patients. A significant increase in BMD was found in 21 CD (42%) and 20 UC (46%) patients. In CD patients the initial BMD values for lumbar spine and femoral neck were inversely correlated to BMD changes at the same sites and the change in body mass index (BMI) was positively correlated to change in the total body BMD. C-reactive protein was significantly higher in CD patients with bone loss. Biochemical markers of bone metabolism could not be used to predict BMD changes. Although it was not significant, there was a relationship between corticosteroid therapy and bone loss in CD.

CONCLUSIONS

Only minor changes in BMD were observed in both CD and UC patients during a 2-year period. The multifactorial pathogenesis of bone loss in IBD makes it difficult to assess the importance of each single contributing factor. However, our results indicate that disease activity and corticosteriod therapy are involved in bone loss in CD patients.