Bone density in a population-based cohort of premenopausal adult women with early onset inflammatory bowel disease

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.

Systematic review of the prevalence and development of osteoporosis or low bone mineral density and its risk factors in patients with inflammatory bowel disease

BACKGROUND

The inflammatory bowel diseases (IBD), Crohn’s disease (CD) and ulcerative colitis (UC) are chronic, immune-mediated disorders of the digestive tract. IBD is considered to be a risk factor for developing osteoporosis; however current literature on this matter is inconsistent.

AIM

To assess prevalence and development of osteoporosis and low bone mineral density (BMD), and its risk factors, in IBD patients.

METHODS

Systematic review of population-based studies. Studies were identified by electronic (January 2018) and manual searches (May 2018). Databases searched included EMBASE and PubMed and abstracts from 2014-2018 presented at the United European Gastroenterology Week, the European Crohn’s and Colitis Organisation congress, and Digestive Disease Week were screened. Studies were eligible for inclusion if they investigated either the prevalence of osteoporosis or osteopenia and/or risk factors for osteoporosis or low BMD in IBD patients. Studies on children under the age of 18 were excluded. Only population-based studies were included. All risk factors for osteoporosis and low BMD investigated in any included article were considered. Study quality and the possibility of bias were analysed using the Newcastle-Ottawa scale.

RESULTS

Twelve studies including 3661 IBD patients and 12789 healthy controls were included. Prevalence of osteoporosis varied between 4%-9% in studies including both CD and UC patients; 2%-9% in studies including UC patients, and 7%-15% in studies including CD patients. Among healthy controls, prevalence of osteoporosis was 3% and 10% in two studies. CD diagnosis, lower body mass index (BMI), and lower body weight were risk factors associated with osteoporosis or low BMD. Findings regarding gender showed inconsistent results. CD patients had an increased risk for osteoporosis or low BMD over time, while UC patients did not. Increased age was associated with decreased BMD, and there was a positive association between weight and BMI and BMD over time. Great heterogeneity was found in the included studies in terms of study methodologies, definitions and the assessment of osteoporosis, and only a small number of population-based studies was available.

CONCLUSION

This systematic review found a possible increase of prevalence of osteoporosis in CD cohorts when compared to UC and cohorts including both disease types. Lower weight and lower BMI were predictors of osteoporosis or low BMD in IBD patients. The results varied considerably between studies.

Prevalence of low bone mineral density in inflammatory bowel disease and factors associated with it

BACKGROUND

Patients with inflammatory bowel disease (IBD) have numerous risk factors for low bone mineral density (BMD). We aimed to study the prevalence of low BMD in IBD and the factors associated with it.

METHODS

BMD was measured by radial quantitative ultrasound, and clinical and biochemical characteristics were compared in prospectively enrolled patients and healthy age and gender-matched controls. Chi-square test, t test for independent samples, analysis of variance (ANOVA), Mann-Whitney U test and Kruskal-Wallis H tests were used as appropriate for univariate analysis to compare the characteristics between patients with and without abnormal BMD. Binary logistic regression analysis was done to determine the factors associated with low BMD in IBD patients.

RESULTS

One hundred and six patients (Crohn's disease [CD] = 35, ulcerative colitis [UC] = 71) and 55 controls were included. Low BMD was equally prevalent in CD, UC and controls (42.9%, 36.6%, 36.4% respectively, p = 0.791). Serum calcium and vitamin D were significantly lower in IBD patients compared to controls (p < 0.001 and p = 0.003, respectively) but not between patients with low and normal BMD. Older age (Odds ratio [OR] = 66.12 [9.299-470.243], p < 0.001), late onset of disease (OR = 4.795 [1.067-21.543], p = 0.041) and absence of steroid usage (OR = 0.272 [0.089-0.832], p = 0.022) were significantly associated with low BMD.

CONCLUSIONS

The prevalence of low BMD in patients with IBD was similar to controls and this was associated with increasing age, late onset of disease, and absence of steroid usage. Judicious use of steroids can help preserve bone health in IBD.

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.

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).

Nonalcoholic fatty liver disease and osteoporosis: a systematic review and meta-analysis

Several major risk factors for osteoporosis have been identified. One of these risk factors is chronic inflammation. Several recent studies have supported the association between low bone mineral density (BMD) and nonalcoholic fatty liver disease (NAFLD), which comprises a spectrum of disorders involving liver inflammation. However, conflicting evidence regarding this association has been obtained thus far. We, therefore, conducted a meta-analysis of observational studies to show the association between NAFLD and BMD. The Cochrane Central Register of Controlled Trials, Cochrane Library, Medline, and Embase were searched from database inception to November 2014 for all observational studies evaluating the association between NAFLD or nonalcoholic steatohepatitis (NASH) and bone mass, BMD, or osteoporosis. All patients were ≥18 years of age and had no other cause of liver disease, osteoporosis, or pathological bone disease at baseline. Risk factors were NAFLD and NASH; control subjects were individuals without NAFLD. Eleven articles underwent full-length review. Data were extracted from five cross-sectional studies involving 1276 participants; 638 had NAFLD. The main meta-analysis showed no significant difference in BMD between patients with fatty liver disease and controls. Among all variables analyzed, body mass index had the strongest and most significant predictive effect on the difference in BMD. Controversy exists regarding the effect of BMD on NAFLD. Further studies are required to fully show this relationship.

A High-Fat Diet Decreases Bone Mass in Growing Mice with Systemic Chronic Inflammation Induced by Low-Dose, Slow-Release Lipopolysaccharide Pellets

Background: Chronic inflammation is associated with increased bone resorption and is linked to osteopenia, or low bone mass. Obesity is also associated with low-grade chronic upregulation of inflammatory cytokines.Objective: This study investigated the effect of high-fat (HF) diet-induced obesity on bone structure changes in growing mice with existing systemic chronic inflammation induced by low-dose, slow-release lipopolysaccharide (LPS).Methods: Forty-eight 6-wk-old female C57BL/6 mice were randomly assigned to 4 treatment groups (n = 12/group) in a 2 × 2 factorial design-control (placebo) or LPS treatment (1.5 μg/d)-and consumed either a normal-fat (NF, 10% of energy as fat) or an HF (45% of energy as fat) diet ad libitum for 13 wk. Bone structure, serum biomarkers of bone turnover, and osteoclast differentiation were measured.Results: No alterations were observed in final body weights, fat mass, or lean mass in response to LPS treatment. LPS treatment increased serum concentration of tartrate-resistant acid phosphatase (TRAP, a bone resorption marker) and bone marrow osteoclast differentiation and decreased femoral and lumbar vertebral bone volume (BV):total volume (TV) by 25% and 24%, respectively, compared with the placebo. Mice fed the HF diet had greater body weight at the end of the study (P < 0.01) due to increased fat mass (P < 0.01) than did mice fed the NF diet. The HF diet increased serum TRAP concentration, bone marrow osteoclast differentiation, and expression of tumor necrosis factor α, interleukin 1β and interleukin 6 in adipose tissue. Compared with the NF diet, the HF diet decreased BV:TV by 10% and 8% at femur and lumbar vertebrae, respectively, and the HF diet was detrimental to femoral and lumbar vertebral bone structure with decreased trabecular number and increased trabecular separation and structure model index.Conclusion: Results suggest that HF diets and systemic chronic inflammation have independent negative effects on bone structure in mice.

Association of chemerin levels and bone mineral density in Chinese obese postmenopausal women

Increasing evidence suggests the association between obesity and bone metabolism. However, whether excessive fat accumulation has a beneficial or adverse effect on bone health remains controversial. Chemerin is a novel adipocyte-derived hormone and a chemoattractant cytokine that regulates adipogenesis. This study was performed to investigate the associations of serum chemerin with bone mineral density (BMD) and serum pro-inflammatory cytokine levels in 543 Chinese obese postmenopausal women. BMD of the femoral neck and lumbar spine, lean mass, and fat mass were measured using dual energy X-ray absorptiometry. Anthropometric assessment and laboratory measurements were performed. The age, time after menopause, and fat mass were negatively correlated with femoral and lumbar BMD, whereas lean mass was positively correlated with aforementioned variables. Furthermore, BMD at the lumbar spine was inversely associated with serum chemerin and TNF-α levels (r = -0.155, P = 0.001; r = -0.147, P = 0.001). Multiple linear regression analyses showed that serum chemerin levels were negatively correlated with BMD at the lumbar site after controlling for the age, lean, and fat mass (β = -0.125, P = 0.001). Chronic low-grade inflammation state in obese population has an inverse effect on bone mass. Chemerin as an adipocytokine and chemoattractant negatively affects the bone mass of Chinese obese postmenopausal women. Further studies are needed to confirm the potential role of chemerin in the crosstalk between bone and fat accumulation in obese population.

Childhood obesity, bone development, and cardiometabolic risk factors

Osteoporosis and obesity are both major public health concerns. It has long been considered that these are distinct disorders rarely found in the same individual; however, emerging evidence supports an important interaction between adipose tissue and the skeleton. Whereas overweight per se may augment bone strength, animal studies suggest that the metabolic impairment that accompanies obesity is detrimental to bone. Obesity during childhood, a critical time for bone development, likely has profound and lasting effects on bone strength and fracture risk. This notion has received little attention in children and results are mixed, with studies reporting that bone strength development is enhanced or impaired by obesity. Whether obesity is a risk factor for osteoporosis or childhood bone health, in general, remains an important clinical question. Here, we will focus on clarifying the controversial relationships between childhood obesity and bone strength development, and provide insights into potential mechanisms that may regulate the effect of excess adiposity on bone.

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

OBJECTIVE

To evaluate peak bone mass attainment in children and adolescents with inflammatory bowel disease and to identify risk factors for suboptimal bone mass attainment.

STUDY DESIGN

We conducted a prospective follow-up study of 47 children and adolescents (24 males) with ulcerative colitis (n = 30) or Crohn's disease (n = 17). They were assessed for lumbar spine areal bone mineral density (aBMD) and for height-adjusted whole body less head bone mineral content (BMC); the values were corrected for bone age.

RESULTS

Altogether, 73% of the patients had completed pubertal development after the median follow-up time of over 5 years. Despite clinical inactivity of the disease in 70% of the patients at the follow-up visit, BMD or BMC Z-scores improved in none of the measurement sites. Lumbar spine aBMD Z-scores (mean difference [95% CI], -0.47 [-0.92 to -0.03]; P = .04) and whole body less head BMC height- and bone age-adjusted Z-scores (-0.52 [-1.01 to -0.02]; P = .04) decreased in patients who were pubertal at baseline and completed their pubertal development during the follow-up. Postpubertal patients had lower aBMD and BMC Z-scores in comparison with prepubertal and pubertal patients. Low lumbar spine aBMD (Z-score < -1.0) was associated with completed pubertal development, underweight, and greater lifetime cumulative weight-adjusted prednisolone dose. Vertebral fractures were detected in 3 patients (6%). One-fourth of the patients had insufficient serum 25-hydroxyvitamin D concentrations (<50 nmol/L).

CONCLUSIONS

The longitudinal follow-up over the pubertal years shows that inflammatory bowel disease poses a significant threat for bone health. The suboptimal peak bone mass attainment may have life-long consequences.

Prevalence of and outcomes associated with corticosteroid prescription in inflammatory bowel disease

BACKGROUND

Corticosteroids are widely used in the management of inflammatory bowel disease (IBD) and are associated with significant side effects. The real world effectiveness of newer drug therapies at reducing corticosteroid use is yet to be reported. The overall burden of corticosteroid use is poorly characterized.

METHODS

We used a population-based IBD database to evaluate the overall prevalence of corticosteroid exposure, corticosteroid-free survival, and heavy corticosteroid use (≥3000 mg of prednisone or equivalent in a 365-day period). Regression models were used to assess predictors of heavy corticosteroid use and the relationship between corticosteroid dose in the first year after diagnosis and the need for continued corticosteroid use and surgery.

RESULTS

The proportion of persons with IBD prescribed corticosteroids within 1, 5, and 10 years of diagnosis was 35.2%, 52.0%, and 62.8%, respectively. Persons with ulcerative colitis, males, and diagnosis before age 25 were more likely to use corticosteroids and have higher cumulative exposure. Heavy corticosteroid use in the first year after IBD diagnosis was associated with a 3 times increased hazard of resective surgery. Cumulative corticosteroid exposure did not decrease among those diagnosed with IBD in more recent years, despite increasing use of immunomodulators.

CONCLUSIONS

A plurality of IBD patients will be exposed to corticosteroids over the course of disease, mostly in the first year. Heavy corticosteroid use in the first year of IBD is a strong predictor of subsequent surgery. Cumulative exposure to corticosteroids use is not decreasing despite increasing uptake of immunomodulators.

Longitudinal assessment of bone mineral density in children and adolescents with inflammatory bowel disease

OBJECTIVES

Low bone mineral density (BMD) is recognized as a potential problem in children with inflammatory bowel disease (IBD). We aimed to describe the longitudinal development of BMD in a population of Swedish pediatric patients with IBD.

METHODS

A total of 144 patients with IBD (93 males; 83 with ulcerative colitis [UC], 45 with Crohn disease [CD]) were examined with dual-energy x-ray absorptiometry at baseline. At follow-up 2 years later, 126 of the initial 144 patients were reexamined. BMD values are expressed as z scores.

RESULTS

Children with UC and CD had significantly lower mean BMD z scores for the lumbar spine (LS) at baseline and after 2 years. The reduction in BMD was equally pronounced in patients with UC and CD, and neither group improved their z score during the follow-up period. Furthermore, significantly lower mean BMD z scores for the LS were found at baseline in boys (-1.1 SD, ±2.7 SD, P < 0.001), but not in girls (-0.0 SD, ±3.0 SD). This finding remained unchanged at follow-up. Subanalyses of the different age groups at baseline showed the lowest BMD values in the group of patients ages 17 to 19 years in boys (mean z score for the LS 1.59 SD, ±3.1 SD) and in girls (mean z score for the LS -3.40 SD, ±3.1 SD); however, at follow-up, these patients had improved their BMD significantly (mean change z score for the LS 1.00 SD, 95% CI 0.40-1.60; 1.90 SD, 95% CI 0.60-3.20).

CONCLUSIONS

In this longitudinal study, the entire group of pediatric patients with IBD showed permanent decreases in their BMD z scores for the LS; however, our data indicate that afflicted children have the potential to improve their BMD by the time they reach early adulthood.

Effects of obesity on bone metabolism

Obesity is traditionally viewed to be beneficial to bone health because of well-established positive effect of mechanical loading conferred by body weight on bone formation, despite being a risk factor for many other chronic health disorders. Although body mass has a positive effect on bone formation, whether the mass derived from an obesity condition or excessive fat accumulation is beneficial to bone remains controversial. The underline pathophysiological relationship between obesity and bone is complex and continues to be an active research area. Recent data from epidemiological and animal studies strongly support that fat accumulation is detrimental to bone mass. To our knowledge, obesity possibly affects bone metabolism through several mechanisms. Because both adipocytes and osteoblasts are derived from a common multipotential mesenchymal stem cell, obesity may increase adipocyte differentiation and fat accumulation while decrease osteoblast differentiation and bone formation. Obesity is associated with chronic inflammation. The increased circulating and tissue proinflammatory cytokines in obesity may promote osteoclast activity and bone resorption through modifying the receptor activator of NF-κB (RANK)/RANK ligand/osteoprotegerin pathway. Furthermore, the excessive secretion of leptin and/or decreased production of adiponectin by adipocytes in obesity may either directly affect bone formation or indirectly affect bone resorption through up-regulated proinflammatory cytokine production. Finally, high-fat intake may interfere with intestinal calcium absorption and therefore decrease calcium availability for bone formation. Unraveling the relationship between fat and bone metabolism at molecular level may help us to develop therapeutic agents to prevent or treat both obesity and osteoporosis. Obesity, defined as having a body mass index ≥ 30 kg/m2, is a condition in which excessive body fat accumulates to a degree that adversely affects health. The rates of obesity rates have doubled since 1980 and as of 2007, 33% of men and 35% of women in the US are obese. Obesity is positively associated to many chronic disorders such as hypertension, dyslipidemia, type 2 diabetes mellitus, coronary heart disease, and certain cancers. It is estimated that the direct medical cost associated with obesity in the United States is ~$100 billion per year.Bone mass and strength decrease during adulthood, especially in women after menopause. These changes can culminate in osteoporosis, a disease characterized by low bone mass and microarchitectural deterioration resulting in increased bone fracture risk. It is estimated that there are about 10 million Americans over the age of 50 who have osteoporosis while another 34 million people are at risk of developing the disease. In 2001, osteoporosis alone accounted for some $17 billion in direct annual healthcare expenditure. Several lines of evidence suggest that obesity and bone metabolism are interrelated. First, both osteoblasts (bone forming cells) and adipocytes (energy storing cells) are derived from a common mesenchymal stem cell and agents inhibiting adipogenesis stimulated osteoblast differentiation and vice versa, those inhibiting osteoblastogenesis increased adipogenesis. Second, decreased bone marrow osteoblastogenesis with aging is usually accompanied with increased marrow adipogenesis. Third, chronic use of steroid hormone, such as glucocorticoid, results in obesity accompanied by rapid bone loss. Fourth, both obesity and osteoporosis are associated with elevated oxidative stress and increased production of proinflammatory cytokines. At present, the mechanisms for the effects of obesity on bone metabolism are not well defined and will be the focus of this review.

Long-term complications, extraintestinal manifestations, and mortality in adult Crohn's disease in population-based cohorts

BACKGROUND

Crohn's disease (CD) is a chronic, progressive, destructive disease. Numerous intestinal and extraintestinal complications and manifestations can occur during its clinical course. This literature review summarizes our current knowledge of the long-term complications, extraintestinal complications, and mortality in CD in adults as reported in population-based studies that include long-term follow-up results.

METHODS

A literature search of English and non-English language publications listed in the electronic databases of Medline (source PubMed, 1935 to July, 2009).

RESULTS

The relative risk of incident fractures is increased in CD patients by ≈30%-40%. These patients have also have a 3-fold increased risk of deep venous thrombosis and pulmonary embolism. A variety of extraintestinal manifestations (primary sclerosing cholangitis, ankylosing spondylitis, iritis/uveitis, pyoderma gangrenosum, erythema nodosum) and diseases (asthma, bronchitis, pericarditis, psoriasis, rheumatoid arthritis, and multiple sclerosis) are associated with CD. The risks of colorectal and small bowel cancers relative to the general population are 1.4-1.9 and 21.1-27.1, respectively. A slightly increased risk of lymphoma, irrespective of medication use, has been reported in a recent meta-analysis of population-based studies. Overall mortality is slightly increased in CD, with a standardized mortality ratio of 1.4.

CONCLUSIONS

CD is frequently associated with disease complications and extraintestinal conditions. Whether the impact of changing treatment paradigms with increased use of immunosuppressives and biologic agents can reduce disease complications and associated conditions is unknown.

Green tea polyphenols attenuate deterioration of bone microarchitecture in female rats with systemic chronic inflammation

Green tea polyphenols (GTP) are promising agents for preventing bone loss. GTP supplementation sustained microarchitecture and improved bone quality via a decrease in inflammation. Findings suggest a significant role for GTP in skeletal health of patients with chronic inflammation.

INTRODUCTION

This study evaluated whether GTP can restore bone microstructure along with a molecular mechanism in rats with chronic inflammation. A 2 [placebo vs. lipopolysaccharide (LPS)]× 2 [no GTP vs. 0.5% GTP (w/v) in drinking water] factorial design was employed.

METHODS

Female rats were assigned to four groups: placebo, LPS, placebo + GTP, and LPS + GTP for 12 weeks. Efficacy was evaluated by examining changes in bone microarchitecture using histomorphometric and microcomputed tomographic analyses and by bone strength using the three-point bending test. A possible mechanism was studied by assessing the difference in tumor necrosis factor-α (TNF-α) expression in tibia using immunohistochemistry.

RESULTS

LPS lowered trabecular volume fraction, thickness, and bone formation in proximal tibia while increasing osteoclast number and surface perimeter in proximal tibia and eroded surface in endocortical tibial shafts. GTP increased trabecular volume fraction and number in both femur and tibia and periosteal bone formation rate in tibial shafts while decreasing trabecular separation in proximal tibia and eroded surface in endocortical tibial shafts. There was an interaction between LPS and GTP in trabecular number, separation, bone formation, and osteoclast number in proximal tibia, and trabecular thickness and number in femur. GTP improved the strength of femur, while suppressing TNF-α expression in tibia.

CONCLUSION

In conclusion, GTP supplementation mitigated deterioration of bone microarchitecture and improved bone integrity in rats with chronic inflammation by suppressing bone erosion and modulating cancellous and endocortical bone compartments, resulting in a larger net bone volume. Such a protective role of GTP may be due to a suppression of TNF-α.

Synergistic effects of green tea polyphenols and alphacalcidol on chronic inflammation-induced bone loss in female rats

Studies suggest that green tea polyphenols (GTP) or alphacalcidol is promising agent for preventing bone loss. Findings that GTP supplementation plus alphacalcidol administration increased bone mass via a decrease of oxidative stress and inflammation suggest a significant role of GTP plus alphacalcidol in bone health of patients with chronic inflammation.

INTRODUCTION

Studies have suggested that green tea polyphenols (GTP) or alphacalcidol are promising dietary supplements for preventing bone loss in women. However, the mechanism(s) related to the possible osteo-protective role of GTP plus D(3) in chronic inflammation-induced bone loss is not well understood.

METHODS

This study evaluated bioavailability, efficacy, and related mechanisms of GTP in combination with alphacalcidol in conserving bone loss in rats with chronic inflammation. A 12-week study of 2 (no GTP vs. 0.5% GTP in drinking water) × 2 (no alphacalcidol vs. 0.05 μg/kg alphacalcidol, 5×/week) factorial design in lipopolysaccharide-administered female rats was performed. In addition, a group receiving placebo administration was used to compare with a group receiving lipopolysaccharide administration only to evaluate the effect of lipopolysaccharide.

RESULTS

Lipopolysaccharide administration resulted in lower values for bone mass, but higher values for serum tartrate-resistant acid phosphatase (TRAP), urinary 8-hydroxy-2'-deoxyguanosine, and mRNA expression of tumor necrosis factor-α and cyclooxygenase-2 in spleen. GTP supplementation increased urinary epigallocatechin and epicatechin concentrations. Both GTP supplementation and alphacalcidol administration resulted in a significant increase in bone mass, but a significant decrease in serum TRAP levels, urinary 8-hydroxydeoxyguanosine levels, and mRNA expression of tumor necrosis factor-α and cyclooxygenase-2 in spleen. A synergistic effect of GTP and alphacalcidol was observed in these parameters. Neither GTP nor alphacalcidol affected femoral bone area or serum osteocalcin.

CONCLUSION

We conclude that a bone-protective role of GTP plus alphacalcidol during chronic inflammation bone loss may be due to a reduction of oxidative stress damage and inflammation.

Spine bone mineral density and VDR polymorphism in subjects with ulcerative colitis

This study established bone mineral density in subjects with ulcerative colitis with respect to disease dissemination and severity and the association between skeletal status and vitamin D receptor (VDR) polymorphism. Forty-seven patients aged 47.6 +/- 14.8 years and 47 age- and sex-matched control subjects were evaluated. Disease duration was 8.6 +/- 7.2 years. Twenty-four subjects demonstrated mild, 17 moderate, and 5 severe forms of ulcerative colitis; local (proctitis and proctosigmoiditis) changes were present in 26 and disseminated changes in 21. Bone mineral density (BMD, g/cm(2)) was assessed at the spine, and distribution of VDR polymorphism was established. In six patients (12.8%) and in two controls (4.25%), T-score for BMD was below -2.5, but mean values of BMD did not differ between all patients and controls. Patients with moderate and severe form of disease had lower BMD measurements than patients with a mild form of colitis ulcerosa (P < 0.05), and subjects with disseminated intestinal changes had lower BMD measurements than subjects with local changes (P < 0.001). Distribution of VDR polymorphism did not differ between patients and controls. Spine Z-score was dependent on VDR polymorphism (P < 0.05) in male and female patients but not in controls. We concluded that, in patients with ulcerative colitis (UC), spine bone mineral density decreases with progression and dissemination of the disease, and that VDR polymorphism is associated with spine bone mineral density. VDR genotype bb is significantly less likely to cause low BMD in male UC patients, and VDR genotype tt is more likely to cause low BMD in female patients.

Decreased bone mineral density is correlated with increased subclinical atherosclerosis in older, but not younger, Mexican American women and men: the San Antonio Family Osteoporosis Study

An association has been reported between cardiovascular disease (CVD) and osteoporosis, perhaps attributable to the presence of common risk factors. To assess this possibility, we measured areal bone mineral density (BMD) and carotid artery intimal medial thickness (IMT), a measure of preclinical atherosclerosis, in 535 women and 335 men from the San Antonio Family Osteoporosis Study. Variance decomposition methods were used to determine whether cross-sectional measures of areal BMD (measured by dual-energy X-ray absorptiometry) of the total hip, spine, and forearm were correlated with IMT, serum lipids, and/or C-reactive protein (CRP), a marker of inflammation, after accounting for known environmental factors. We observed significant inverse correlations of IMT and BMD at all bone sites in women >60 years of age (P < 0.001) and modest positive correlations (not significant) of IMT on hip BMD (P < 0.1) in women <60 years of age. Similarly, we observed negative correlations between IMT and forearm BMD in men >60 years of age (P < 0.001) and positive correlations in men <60 years of age (P = 0.05). Variation in risk factors for CVD, including serum levels of low- and high-density lipoprotein cholesterol, low-density lipoprotein particle size, triglycerides, paraoxonase 1 activity, and CRP did not account for the relationship between BMD and IMT in either older or younger men or women. In summary, our results demonstrate that decreased BMD is correlated with increased IMT in older (but not younger) Mexican American men and women, independent of serum CVD risk factors.

Inflammatory bowel diseases as secondary causes of osteoporosis

Inflammatory bowel disease (IBD), comprising Crohn's disease and ulcerative colitis, is associated with an increased risk of osteoporosis and bone fractures. Initial studies suggested very high rates of osteoporosis in IBD, but more recent studies have suggested that bone mineral density (BMD) is often normal in patients with IBD and typically changes little over time. Nonetheless, IBD is associated with an increased risk of fractures. Doctors managing patients with IBD must consider a variety of risk factors, not just BMD measurements, in assessing fracture risk. Advances have been made in exploring the pathogenesis of osteoporosis in IBD. The evolution of knowledge regarding receptor for activated factor of nuclear factor kappaB (RANK), its ligand RANKL, and osteoprotegerin (OPG), which serves as a decoy receptor, has enhanced the understanding of both osteoporosis and T-cell immunobiology. Recent clinical studies in patients with IBD have revealed that serum OPG levels may be elevated and inflamed intestinal tissue secretes increased amounts of OPG. It is suspected that OPG levels are elevated as a counterregulatory response to low BMD, as serum OPG levels in IBD have been found to be inversely associated with BMD. Finally, in animal models of IBD, exogenous OPG has reversed both the osteopenia and the enterocolitis, suggesting that it may have a therapeutic role in human IBD.

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.

Systemic bone loss and induction of coronary vessel disease in a rat model of chronic inflammation

Clinically, osteopenia or low bone mass has been observed in a variety of chronic inflammatory diseases, and elevated proinflammatory mediators have implicated this process. The purpose of this study was to develop an in vivo model of bone loss induced by chronic systemic inflammation. Time-release pellets designed to deliver one of three doses of LPS: Low (3.3 microg/day), High (33.3 microg/day), or Placebo over 90 days, were implanted subcutaneously in 3-month-old male Sprague-Dawley rats (n = 8/group). Neutrophil counts, indicative of ongoing inflammation, were elevated (P < 0.05) in both LPS groups at 30 days post-implant and remained significantly elevated in the High dose throughout the 90-day study period. At the end of the study, bone loss occurred in the femur as indicated by decreased bone mineral density (BMD) in both LPS-treated groups, but vertebral BMD was reduced in the High dose animals only. Microcomputed tomography revealed that trabecular bone volume (BV/TV) of the proximal tibial metaphysis tended to be reduced in the High dose LPS group. Deleterious effects on trabecular number (TbN) and trabecular separation (TbSp) were observed in both LPS-treated groups, but only the High dose group reached statistical significance. These alterations in trabecular microarchitecture resulted in compromised biomechanical properties. No changes in cortical thickness, porosity, or area of the tibia midshaft were evident at either dose of LPS. Up-regulation of the proinflammatory mediators, cyclooxygenase (COX)-2, interleukin (IL)-1, and tumor necrosis factor (TNF)-alpha was demonstrated in the metaphyseal region where the deleterious effects of LPS were observed. In addition to these alterations in bone, trichrome staining indicated changes in the coronary arterioles, consistent with vascular disease. Utilization of a LPS time-release pellet appears to provide an in vivo model of chronic inflammation-induced bone loss and a potentially novel system to study concurrent development of osteopenia and vascular disease.

[Bone mineral density evaluation in inflammatory bowel disease patients]

BACKGROUND

Inflammatory bowel disease patients have shown greater reduction of the bone mineral density compared to healthy people.

AIM

To evaluate the bone mineral density in a population of patients with inflammatory bowel disease.

METHODS

Ninety patients from 20 to 50 years old, of the Inflammatory Bowel Disease Ambulatory of the Gastroenterology Service of the Clinics Hospital, Curitiba, PR, Brazil, were selected for the evaluation. From those, 76 completed all the stages of the evaluation. The densitometry was made from lumbar column and right femur with a dual-energy x-ray absorptiometry (Hologyc QDR 1000/W) device.

RESULTS

The inflammatory bowel disease patients had a significant reduction of the bone mineral density in all the evaluated parts, femur neck, total femur and lumbar column. The analysed variables, disease activity index, usage of corticoids, the lack of physical activities, the index body mass and previous surgeries did not have influence in the results.

CONCLUSION

Reduced bone mineral density was founded in inflammatory bowel disease patients of the Clinics Hospital, mainly in the Crohn's disease patients, as described in literature. None analyzed variables had significant correlation to the bone mineral density.

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.

Therapy Insight: osteoporosis in inflammatory bowel disease—advances and retreats

There is a discrepancy between the high rates of reduced bone mineral density (BMD) reported in patients with inflammatory bowel disease (IBD) and the relatively low fracture rates observed in population-based studies. When fractures occur, they are most common among the elderly IBD population. It has become clear that BMD is but one of several important factors to be considered when assessing fracture risk. Ideally, BMD should be assessed selectively, as opposed to assessing this measure in all IBD patients simply because they carry an IBD diagnosis. Preventing bone loss should begin with an attempt to limit corticosteroid-induced bone loss. This can be done by using the minimum effective prednisolone dose, substituting budesonide when appropriate, administering other steroid-sparing immunomodulators, or by prescribing additional agents that enhance bone health. The administration of calcium and vitamin D appears to maintain or enhance bone mass. Bisphosphonates are of unclear additional benefit to the majority of patients who are at low fracture risk. Although more data are required to understand the best strategy to prevent fractures, a greater appreciation of the role of selective BMD testing and the utility of simple therapeutic strategies (such as calcium and vitamin D supplements) is emerging.

Management of extraintestinal manifestations and other complications of inflammatory bowel disease

The past 18 months have seen many studies of the prevalence, pathogenesis, and treatment of the extraintestinal manifestations of inflammatory bowel disease (IBD). Inhibitors of tumor necrosis factor alpha have shown effectiveness in randomized trials for the treatment of spondyloarthropathies and ocular manifestations. Open-label studies suggest that these agents may be effective for pyoderma gangrenosum as well. The epidemiology of primary sclerosing cholangitis (PSC), and its relationship to IBD, is becoming clearer. Colorectal neoplasia in PSC remains an important clinical problem. Osteoporosis occurs more commonly in IBD, but the relative importance of corticosteroid use versus underlying chronic bowel inflammation as risk factors remains controversial. Chromoendoscopy may be an important means to improve detection of colorectal neoplasia in IBD. Observational studies suggest that prolonged use of aminosalicylates is associated with decreased risk of neoplasia, but data are conflicting. A randomized trial of ursodeoxycholic acid in PSC showed decreased risk of colorectal neoplasia in patients receiving the drug relative to those on placebo.

Osteoporosis and Crohn's disease

Osteoporosis and osteopenia have been reported frequently in patients with inflammatory bowel disease, most notably Crohn's disease.

OBJECTIVES

To determine the prevalence and risk factors of osteoporosis in patients with Crohn's disease.

METHODS

Prospective study of 56 patients with Crohn's disease, 34 men and 22 women with a mean age of 32 +/- 10.4 years (18-54 years) and no history of disorders known to influence bone metabolism. Dual-energy X-ray absorptiometry measurements of bone mineral density (BMD) were obtained at the femoral neck and lumbar spine. A multivariate model including those factors significantly associated with low BMD in the univariate analysis was used to identify independent risk factors.

RESULTS

Osteoporosis was found in 35.7% and osteopenia in 23.2% of patients. Low BMD was significantly associated with low body mass index (BMI), colonic involvement, and glucocorticoid therapy. Low BMI was an independent risk factor for low BMD. Malnutrition with BMI < or =18 kg/m2 was noted in 21 patients, of whom 76.2% had low BMD values, as compared to 48.6% of the patients whose BMI was >18 kg/m2 (P = 0.03, odds ratio = 3.4).

CONCLUSION

Among risk factors for bone loss in patients with Crohn's disease, malnutrition plays a prominent role that deserves attention when planning treatment programs.

Current advances in bone health of disabled children

PURPOSE OF REVIEW

Bone health is now recognized to contribute to overall lifetime management of children, adolescents, and adults with disabling conditions including physical and intellectual disability and with many chronic disease processes. Such disorders have multiple components, with aspects of care covering a wide number of specialist practices. This review will highlight advances in understanding the nature of bone mass accumulation through childhood and adolescence, the impingement of a spectrum of chronic and disabling diseases and their treatments on bone, and will address current approaches to interpretation of bone mass in the growing skeleton and interventional strategies for improving outcomes for this group.

RECENT FINDINGS

Increased skeletal fragility in the disabled child is well recognized. Insights into the contributions of skeletal size and bone strength in males and females have altered interpretation of data, allowing a new focus on determinants of future bone health, particularly with regard to the contributions of growth and puberty. Strategies to address bone health including public and medical education concerning consumption of calcium, appropriate selection of vitamin D preparations, pubertal contribution to phases of growth and possible specialist use of newer drugs, such as bisphosphonates where indicated, are changing the outlook for this large group.

SUMMARY

Implications of these changed understandings provide a new focus on maximizing bone mass accumulation by the end of adolescence within the constraints of what is possible to achieve for an individual and for provision of an holistic approach to bone health.

Review article: bone disease in inflammatory bowel disease

Inflammatory bowel disease (IBD) is associated with an increased incidence of osteoporosis. Osteoporosis with osteoporotic pain syndromes, fragility fractures and osteonecrosis accounts for significant morbidity and impacts negatively on the quality of life. It is generally agreed that there is a need to increase awareness for inflammatory bowel disease-associated osteoporosis. However, the best ways in which to identify at-risk patients, the epidemiology of fractures and an evidence-based rational prevention strategy remain to be established. The overall prevalence of IBD-associated osteoporosis is 15%, with higher rates seen in older and underweight subjects. The incidence of fractures is about 1 per 100 patient years, with fracture rates dramatically increasing with age. While old age is a significant risk factor, disease type (Crohn's disease or ulcerative colitis) is not related to osteoporosis risk. Corticosteroid use is a major variable influencing IBD-associated bone loss; however, it is difficult to separate the effects of corticosteroids from those of disease activity. The recommendations in inflammatory bowel disease are similar to those for postmenopausal osteoporosis, with emphasis on lifestyle modification, vitamin D (400-800 IE daily) and calcium (1000-1500 mg daily) supplementation and hormone replacement therapy (oestrogens/selective oestrogen receptor modulators in women, testosterone in hypogonadal men). Bisphosphonates have been approved for patients with osteoporosis (T-score < 2.5), osteoporotic fragility fractures and patients receiving continuous steroid medication. Data on the recently Food and Drug Administration-approved osteoanabolic substance parathyroid hormone and on osteoprotegerin are promising in terms of both steroid-induced and inflammation-mediated osteoporosis, the key elements of inflammatory bowel disease-associated bone disease.

Interleukin-10 knockout mouse: a model for studying bone metabolism during intestinal inflammation

The objective was to compare bone mass (bone mineral content [BMC], bone mineral density [BMD]) and biomechanical strength of femurs and lumbar vertebrae from male and female wild-type (WT) and IL-10 knockout (KO) mice to determine if the IL-10 KO mouse model is appropriate for studying inflammation-associated bone abnormalities and potential interventions. Offspring from IL-10 KO and WT mice (n = 15 to 19 mice/gender per group) were studied until 13 weeks of age. IL-10 KO mice had a higher (P < 0.05) colonic histologic injury score and serum proinflammatory cytokines (IL-6, IL-1beta, TNF-alpha) than WT mice. IL-10 KO mice also experienced bone abnormalities as femur and verterbral BMC and BMD were lower (P < 0.05) compared with WT mice. Moreover, some biomechanical strength parameters such as femur yield load (P = 0.057) and resilience (P < 0.05) and peak load of lumbar vertebra 3 (P < 0.05) were lower than WT mice. Due to differences in body size, males had greater (P < 0.05) femur and vertebral bone mass as well as femur weight, length, yield load, resilience, and peak load than females. A significant interaction (genotype x gender) was only observed for femur resilience in which male WT mice had a greater (P = 0.009) resilience than all other groups. These results demonstrate that IL-10 KO mice develop bone abnormalities that accompany intestinal inflammation and elevated serum proinflammatory cytokines. Thus, the IL-10 KO mouse model may be useful for studying inflammation-associated bone abnormalities and potential therapeutic interventions.

Review article: Osteoporosis and inflammatory bowel disease

Studies using dual-energy X-ray absorptiometry have suggested a high prevalence of osteoporosis in inflammatory bowel disease. However, population-based data on fracture incidence suggest only a small increased risk of fracture amongst patients with inflammatory bowel disease compared with the general population. Therefore, it would be helpful to identify patients with inflammatory bowel disease at particularly high risk for fracture so that these risks might be modified or interventions might be undertaken. The data on calcium intake as a predictor of bone mineral density are conflicting. Although there are data suggesting that a one-time survey to determine current calcium intake will not help to predict bone mineral density in inflammatory bowel disease, persistently reduced calcium intake does appear to lead to lower bone mineral density. In the general population, body mass is strongly correlated with bone mineral density, which also appears to be true in Crohn's disease. Hence, subjects with inflammatory bowel disease and considerable weight loss, or who are obviously malnourished, could be considered for bone mineral density testing, and the finding of a low bone mineral density would suggest the need for more aggressive nutritional support. Although vitamin D is undoubtedly important in bone health, vitamin D intake and serum vitamin D levels do not correlate well with bone mineral density. Sex hormone deficiency can also adversely affect bone health, although a well-developed strategy for sex hormone measurements in patients with inflammatory bowel disease remains to be established. Ultimately, the determination of genetic mutations that accurately predict fracture susceptibility may be the best hope for developing a simplified strategy for managing bone health in inflammatory bowel disease. The therapy of osteoporosis in inflammatory bowel disease has been adapted from other osteoporosis settings, such as post-menopausal or corticosteroid-induced osteoporosis. To date, there remains no therapy proven to be efficacious in inflammatory bowel disease-related osteoporosis; however, calcium and vitamin D supplementation and bisphosphonates have their roles.

Lack of relationship of calcium and vitamin D intake to bone mineral density in premenopausal women with inflammatory bowel disease

OBJECTIVES

Low bone mineral density has been widely reported in patients with inflammatory bowel disease (IBD). The exact etiology of this condition is not completely understood but is suggested to be multifactorial, possibly including low calcium and vitamin D intake. The objective of this study was to assess calcium and vitamin D intake and its relationship to bone mineral density (BMD) in premenopausal women with IBD.

METHODS

A total of 70 premenopausal women with IBD (mean age 33.3 yr, range 18-44 yr) drawn from the population-based University of Manitoba IBD Research Registry participated in the study. Calcium and vitamin D intake was determined using a semiquantitative food frequency questionnaire and compared to the Dietary Reference Intake values for adequacy. BMD of total body, lumbar spine, femoral neck, and hip was measured using dual-energy x-ray absorptiometry.

RESULTS

Of the 70 subjects, 66 successfully completed the study. Inadequate calcium intake (<1000 mg/day) was found in 69.7% of the subjects. This low intake group had a mean calcium intake of 508 mg/day. Inadequate vitamin D intake (<200 IU/day) was found in 53% of the subjects with a mean vitamin D intake of 76 IU/day in this group. Calcium and vitamin D intake correlated with each other with R2=0.57, p<0.00001. Daily calcium intake was not significantly different for subjects with T scores greater than -1 (901 mg) and for subjects with T scores less than -1 (875 mg, p=0.44). Daily vitamin D intake was not significantly different for subjects with T scores greater than -1 (297 IU) compared with subjects with T scores less than -1 was (267 IU, p=0.33). Comparing subjects with T scores greater than -1 to those with T score less than -1, there was no difference in the percentage of subjects ingesting >1 g/day calcium (14/43 vs 8/23, p=0.86) or in those with vitamin D intake >200 IU/day (21/43 vs 9/23, p=0.45).

CONCLUSIONS

The results show that, on average, premenopausal women with IBD have less than the recommended intake for calcium and vitamin D. However, this does not seem to influence BMD. Calcium and vitamin D intake is not a predictor of bone status in premenopausal women with IBD.