Measuring Bone Turnover Research Articles

P0415 Bone turnover biomarkers alteration in patients with Inflammatory Bowel Disease

Abstract Background Because of glucocorticoids, chronic inflammation, malabsorption, and other factors, patients with inflammatory bowel disease (IBD) are at varying risk for osteoporosis (OP) and decreased bone mineral density. This puts individuals at risk for osteoporotic fractures, which have a negative impact on their quality of life. The purpose of this study is to measure bone turnover markers (BTMs) representing bone resorption and formation in an Egyptian cohort of IBD patients, compare them to healthy controls, and investigate their relationship to disease activity, extension, and treatment modalities. Methods The cross-sectional study included 92 participants: 45 IBD patients, 25 ulcerative colitis (UC), 20 Crohn’s disease (CD), and 47 controls. Overnight fasting blood samples were withdrawn for BTMs including bone formation markers (Procollagen I N-terminal propeptide {PINP} and bone specific alkaline phosphatase {BSAP}), bone resorptive marker (C-terminal telopeptide of type I collagen {CTX}). Results Serum CTX, PINP, and BALP levels increased significantly in IBD patients, indicating increased turnover and metabolic bone disease, but there were no significant differences between the UC and CD groups. In terms of disease activity and intestinal involvement, BTM levels in UC and CD patients were comparable. Anti-tumour necrosis-α (anti-TNF-α) users had considerably reduced CTX and PINP increases compared to non-users. Conclusion Biochemical testing with BTMs may be useful in the initial evaluation of bone health in IBD patients. Anti-TNF-α users were less likely to experience bone alterations compared to non-users.

Osteoporosis and low bone mass among schizophrenia and bipolar disorder: A cross-sectional study with newly diagnosed, drug-naïve subjects

BackgroundA growing body of data shows that schizophrenia (SCZ) and bipolar disorder (BD) have substantial metabolic risks; however, few studies have focused on bone metabolism. This study aimed to assess the prevalence and associated influencing factors of low bone mass and osteoporosis in SCZ and BD before pharmacological effects occur. Methods108 healthy controls (HCs) and drug-naïve individuals with SCZ (n = 56) and BD (n = 130) had their lumbar spine (L1–L4) and left femur (Neck/Trochanter/Ward's triangle) bone mineral density (BMD) determined using dual-energy X-ray absorptiometry. Besides, we measured bone turnover markers (BTMs) levels, including procollagen I N-terminal propeptide, osteocalcin, and C-terminal cross-linking telopeptide of type I collagen in different groups. ResultsIndividuals with SCZ and BD had significantly lower BMD and significantly higher prevalence of low bone mass and osteoporosis compared with HCs. In the main observation regions of the total lumbar (F = 18.368, p < 0.001) and left femur (F = 14.790, p < 0.001), BMD was lower in individuals with SCZ and BD than HCs, with SCZ showing lower BMD than BD. The osteocalcin (H = 11.421, p = 0.003) levels were significantly higher in SCZ and BD than HCs.Binary regression analysis showed that SCZ or BD was an independent risk factor for low bone mass and osteoporosis. In addition, sex, age, and BTMs also influenced the occurrence of low bone mass and osteoporosis. LimitationsCross-sectional study. ConclusionThe results findings of the study might contribute to our understanding of the increased risk of bone metabolism in SCZ and BD. Clinical trial registrationwww.chictr.org.cn, identifier ChiCTR1900021379.

Biochemical Markers of Calcium and Bone Metabolism during and after Lactation in Ugandan Women with HIV on Universal Maternal Antiretroviral Therapy.

We reported accentuated lactational decreases in areal bone mineral density and only partial skeletal recovery after lactation in Ugandan women with HIV (WWH) initiated on tenofovir disoproxil fumarate-based antiretroviral therapy (TDF-based ART) during pregnancy compared to women without HIV (REF). WWH also had higher breast milk calcium in the first months of lactation. To investigate the mechanisms, we measured bone turnover markers (bone resorption: C-terminal telopeptide [CTX]; bone formation: procollagen type 1 N-terminal propeptide [P1NP], bone-specific and total alkaline phosphatase [BALP, TALP]), hormones (parathyroid hormone [PTH], intact fibroblast growth factor 23 [FGF23], 1,25-dihydroxyvitamin D [1,25(OH)2 D]), vitamin D status (25-hydroxyvitamin D [25OHD]), and indices of mineral metabolism and renal function. Blood and urine samples collected at 36 weeks of gestation, 14 and 26 weeks of lactation, and 3-6 months after lactation were analyzed. Mean 25OHD was >50 nmol/L throughout. Both groups experienced similar biochemical changes during pregnancy and lactation to women in other settings, but within these patterns, the two groups differed significantly. Notably, WWH had higher PTH (+31%) and lower 1,25(OH)2 D (-9%) and TmP/GFR (-9%) throughout, lower P1NP (-27%) and plasma phosphate (-10%) in pregnancy, higher CTX (+15%) and BALP (+19%), and lower eGFR (-4%) during and after lactation. P1NP/CTX ratio was lower in WWH than REF in pregnancy (-21%), less so in lactation (-15%), and similar after lactation. Additionally, WWH had lower plasma calcium (-5%), lower FGF23 (-16%) and fasting urinary calcium (-34%) at one or both lactation timepoints, and higher fasting urinary phosphate (+22%) at 26 weeks of lactation and after lactation. These differences resemble reported TDF effects, especially raised PTH, increased bone resorption, decreased bone formation, and decreased renal function, and may explain the observed differences in bone mineral density and breast milk calcium. Further studies are needed to determine whether HIV and TDF-based ART have long-term consequences for maternal bone health and offspring growth. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

#5559 BONE SPECIFIC ALKALINE PHOSPHATASE AS A POTENTIAL BIOMARKER OF AUTOSOMAL DOMINANT POLYCYSTIC KIDNEY DISEASE PROGRESSION

Abstract Background and Aims Autosomal dominant polycystic kidney disease (ADPKD) is a systemic disease, resulting in a dysfunction of the primary cilium, a sensory organelle ubiquitously present in human cells. Ciliopathies are characterized by disorders of seemingly unrelated organs and functions, which depend on integrity of the primary cilium, among them the skeleton and the kidneys. A distinct bone phenotype has been reported in ADPKD patients in several cohort studies. Findings, however, were heterogenous. Present study aimed to measure bone turnover biomarkers in patients with ADPKD across disease severity measured by eGFR and height-adjusted total kidney volume (HtTKV). Method In this cross-sectional study, we included 80 ADPKD patients with different chronic kidney disease (CKD) stages (G1 and G2 (n = 39), and G3 and G4 (n = 41)) with median age 44.0 (33.5-50.5) years, 62.5% men, and BMI 25.1 (23.3-28.7) kg/m2. HtTKV was measured with magnetic resonance imaging. We measured biochemical parameters of mineral metabolism, including bone specific alkaline phosphatase (BALP) and total ALP, calcium (Ca), parathyroid hormone (PTH), and 25(OH) vitamin D (25(OH)D) and bone strength index (BSi) with microindentation, using an OsteoProbe® (Active Life Scientific, USA). Microindentation is minimally invasive technique assessing bone quality. The cortical bone at the mid-shaft of the tibia is penetrated with the indenter to measure bone resistance. Results Bone biomarkers expressed as median and interquartile range were as follow: Ca 9.6 (9.3-9.9) mg/dL, BALP 9.0 (7.0-12.5) ug/L, ALP 59.0 (46.0-72.0) U/L, PTH 43.5 (26.6-72.0) pg/mL and 25(OH)D 25.4 (16.6-33.5) ng/mL. Median BSi was 79.1(73.5-82.1) in men and 68.5 (62.1-78.6) in women (lower than the average score in healthy caucasians). Among analyzed bone markers only BALP significantly associated with severity of ADPKD. BALP - but not eGFR - associated with HtTKV and was different across HtTKV tertiles. BALP was also higher in the highest BSi group, but BSi did not associate with HtTKV (Figure 1). Conclusion In patients with ADPKD and different stages of CKD, BALP associates with bone strength and kidney volume, suggesting that it may be a sensitive marker of systemic ADPKD manifestations. Further studies should elucidate whether BALP may be a more sensitive marker for ADPKD progression than GFR.

The Relationship Between Stress Fractures and Bone Turnover Markers Is Unclear in Athletic and Military Populations: A Critically Appraised Topic

Clinical Scenario: Having an indication of how bone is remodeling in response to training load could help identify athletes and military personnel at increased stress fracture (SFx) risk. Direct assessment of bone remodeling is impractical. Biochemical markers of bone turnover are used as an indirect measure of bone remodeling and have potential to inform prevention and treatment efforts. To date, the relationship between bone turnover markers and SFxs in athletes or military personnel remains unclear. Clinical Question: Are SFxs related to bone turnover markers in athletes and military personnel? Summary of Key Findings: Seven met eligibility criteria. In five studies, an association between SFxs and bone turnover markers existed. Clinical Bottom Line: The evidence supporting a relationship between SFxs and bone turnover markers in athletes and military personnel is mixed. While five of the seven studies reported some type of relationship, no studies prospectively measured bone turnover markers in a group of athletes or military personnel without an SFx or without SFx history and followed them over time to reassess bone turnover markers upon SFx occurrence. Strength of Clinical Recommendation: In accordance with the Strength of Recommendation Taxonomy, Grade C is the most appropriate strength of recommendation rating.

Research on biochemical indexes of bone metabolism in bipolar disorder: A cross-sectional study with newly diagnosed, drug-naïve patients

BackgroundIn recent years, the metabolic abnormalities associated with bipolar disorder (BD) have attracted people's attention. However, clinical studies on bone metabolism in individuals with BD are unavailable. This study was designed to assess biochemical indexes of bone metabolism and related influencing factors. MethodsWe measured bone turnover markers (BTMs), including procollagen Ⅰ N-terminal propeptide (PⅠNP), osteocalcin (OC) and C-terminal cross-linking telopeptide of type I collagen (CTX-I), and index of calcium and phosphorus metabolism in 100 drug-naïve individuals with BD (DSM-5) and 91 healthy volunteers. Besides, sociodemographic and clinical assessment were collected. Between-group comparisons and within subgroup analysis were performed. ResultsThe PⅠNP (t = 3.715, p < 0.001), OC (t = 2.117, p = 0.036), parathyroid hormone (PTH, t = 3.877, p < 0.001), vitamin D (t = 2.065, p = 0.041), insulin (t = 4.208, p < 0.001) and insulin resistance (t = 2.888, p = 0.004) levels in the drug-naive BD group was significantly higher than those in the healthy control (HC) group. The level of calcium (t = −2.124, p = 0.035) in the drug-naive BD group was significantly lower than that of the HC group. But OC and vitamin D loses statistical significance after Bonferroni correction. However, there was no significant difference in the CTX-I level between the two groups. There are gender differences in the level of BMTs in individuals with BD, but this phenomenon was not found in the HC subgroup. It is shown that diagnosed BD, gender, age and BMI may affect the PINP levels through multiple linear regression analysis. ConclusionThe biochemical indexes of bone metabolism in drug-naive individuals with BD were more active than that of the healthy controls in a sample from the Chinese Han nationality. The finding provides new evidence for our understanding of bone metabolism in individuals with BD.

Mineral Density and Markers of Bone Remodelling in Young Athletes in Response to Weightlifting Exercise: A Pilot Study

Background: Weightlifting is a practice that exerts a high degree of pressure on the skeleton when supporting large loads of weight. The practice of exercise contributes by improving bone mineral density (BMD) and can prevent problems associated with low BMD. Objective: The objective of the present study was to determine BMD and measure bone turnover using blood markers in weightlifting athletes in response to exercise. Methods: The study included 16 athletes and 16 controls of both sexes in the range of 18 to 22 years old. BMD was determined at the femoral neck, hip, lumbar spine, and Total Mineral Density (TMD). The value of the total mineral density (TMDV) was obtained from the sum of the BMD of the evaluated regions. Bone formation and resorption in blood were evaluated by Alkaline Phosphatase (ALP) and Acid Phosphatase (ACP), respectively. In addition, the concentration of urea and Creatine Kinase (CK) were determined. Results: The mean BMD of the lumbar spine and TMDV was of 1.2 g/cm2 in female and male athletes. In young people who did not practice weightlifting, BMD in the lumbar spine (0.9 g/cm2 in both groups) and TMDV (1.05 g/cm2 in women and 1.11 g/cm2 in men) were significantly lower (p &lt;0.05). The activity in bone formation and CK in male athletes was twice as high compared to the other groups. The blood urea concentration in athletes (32.7- 38.0 mg/dL) was significantly higher (p &lt;0.05) compared to the control groups (19.3-18.8 mg/dL). Conclusion: The practice of weightlifting benefits bone mass gain in the lumbar spine. These findings suggest that exercises in which high weight loads are supported promote bone turnover and mineralization to prevent bone weakening.

Bone Metabolism, Bone Mineral Content, and Density in Elite Late Teen Female Sprinters.

With intensive training, bone injuries are a major concern for athletes. To assess bone condition, we often measure bone turnover markers, bone mineral content and density; however, in junior athletes, it is not easy to distinguish changes caused by bone injuries from those caused by growth, because the metabolism is increased in both cases. Moreover, although some studies have examined female endurance athletes, knowledge regarding changes in static and dynamic bone conditions in late teen athletes is limited. In this study, we measured the bone mineral content and density, as well as bone turnover markers, in 40 elite female sprinters in their late teens. Whole body mode dual-energy X-ray absorptiometry was performed to measure bone mineral content and density. Blood samples were collected to determine bone resorption and formation markers at the end of track season in 2016 and during the same period of the following year. Body weight and bone mineral content significantly increased, and tartrate-resistant acid phosphatase type 5b, bone-type alkaline phosphatase, and osteocalcin significantly decreased after a year. Furthermore, the rate of change in bone mineral content was higher in younger athletes, indicating that bone growth approaches completion in the late teen years and that bone metabolism accordingly decreases.

Time-Restricted Eating for 12 Weeks Does Not Adversely Alter Bone Turnover in Overweight Adults.

Weight loss is a major focus of research and public health efforts. Time-restricted eating (TRE) is shown to be effective for weight loss, but the impact on bone is unclear. Short-term TRE studies show no effect on bone mineral density (BMD), but no study has measured bone turnover markers. This secondary analysis examined the effect of 12 weeks of TRE vs. unrestricted eating on bone turnover and BMD. Overweight and obese adults aged 18–65 y (n = 20) were randomized to TRE (ad libitum 8-h eating window) or non-TRE. Serum N-terminal propeptide of type I collagen (P1NP), cross-linked N-telopeptide of type I collagen (NTX), and parathyroid hormone (PTH) levels were measured and dual-energy X-ray absorptiometry (DXA) scans were taken pre- and post-intervention. In both groups, P1NP decreased significantly (p = 0.04) but trended to a greater decrease in the non-TRE group (p = 0.07). The treatment time interaction for bone mineral content (BMC) was significant (p = 0.02), such that BMC increased in the TRE group and decreased in the non-TRE group. Change in P1NP was inversely correlated with change in weight (p = 0.04) overall, but not within each group. These findings suggest that TRE does not adversely affect bone over a moderate timeframe. Further research should examine the long-term effects of TRE on bone.

Gender-Affirming Hormone Therapy and Bone Health: Do Different Regimens Influence Outcomes in Transgender Adults? A Narrative Review and Call for Future Studies.

Gender-affirming hormone therapy (GAHT) influences bone health in transgender individuals. Several hormone preparations and administration routes are available for GAHT, but no studies have compared clinical and laboratory bone health measures across different GAHT regimens. We searched PubMed (MEDLINE), Embase, and Google Scholar for studies measuring bone turnover markers and bone mineral density before and during GAHT in transgender adults. We summarized bone health data by hormone type and administration route (estrogen or testosterone; oral, transdermal/percutaneous, intramuscular). Among trans women, we also examined outcomes among regimens containing different adjunctive agents (antiandrogens or gonadotropin-releasing hormone analogs). Most hormone preparations maintained or increased areal bone mineral density among trans adults taking GAHT for at least 12 months from baseline. Different bone turnover markers were measured across studies, and we were unable to compare or comment on the direct influence of selected hormone preparations on these clinical laboratory measures. Larger and uniformed studies are needed to measure volumetric bone mineral density and biomarkers of bone metabolism in trans adults taking standardized GAHT regimens.

THE IMPACT OF REGULAR FOOTBALL TRAINING ON BONE TURNOVER MARKERS

Introduction The condition of the skeleton is important not only in the perspective of osteoporosis prevention, but also as a factor affecting the frequency of injuries excluding physical activity. Monitoring the impact of specific sports on osteoclasts and osteoblasts acitivity allows optimization of programming of physical activity limiting the risk of bone mineralization disorders. The review analyzes available papers on the impact of regular football training on skeletal physiology changes analyzed by measuring bone turnover markers in the body. Aim Determining the impact of regular football training on bone mass regulation by analyzing bone turnover markers. Material and methods PubMed and SPORTDiscus with Full Text databases were searched using the keyword combination “the name of team sport” + bone turnover. There is no clinical trials about bone turnover markers among handball, hockey, basketball and volleyball players in the available literature that meet the inclusion criteria, so the topic of the review was narrowed down to football (soccer). After applying the exclusion criteria, five studies were qualified. Results In the analyzed papers, the concentration of osteocalcin, N-terminal procollagen type I extension propeptide and C-terminal telopeptide of type I collagen in blood increased as a result of regular football training. In 3 papers statistically significant (p &lt; 0.05) increases were noted. Conclusions Football training can stimulate bone metabolism, being an effective and attractive form of bone fracture prevention, regardless of your level of sport. Due to the limited availability of studies, there is a high need for further studies describing the impact of physical activity on bone metabolism.

The effect of vitamin MK-7 on bone mineral density and microarchitecture in postmenopausal women with osteopenia, a 3-year randomized, placebo-controlled clinical trial.

Vitamin K is a cofactor in the carboxylation of osteocalcin (OC) and carboxylated OC promotes mineralization of bone. Clinical studies suggest that vitamin K2 prevents bone loss. The aim of the study was to investigate the effect of vitamin K2 as an add-on to calcium and vitamin D supplementation on osteocalcin, bone mass, and microarchitecture in postmenopausal women. We conducted a randomized placebo-controlled double-blinded clinical trial, including 142 postmenopausal women with osteopenia who received vitamin K2 (375μg MK-7) or placebo daily for 3years. Both groups received vitamin D3 (38μg/day) and calcium (800mg/day). We measured bone turnover markers in serum and bone mineral density and microarchitecture by DXA and HRpQCT. Undercarboxylated osteocalcin decreased in the MK-7-group (- 65.2 ± 23.5%) (mean ± SD) compared with the placebo group (- 0.03 ± 38.5%), p < 0.01 after 1year. After 3years, aBMD decreased at all sites without differences between the MK-7 and placebo-treated women (p > 0.09). aBMD decreased at the total hip by 1.5 ± 2.5% and 2.4 ± 2.7% in the MK-7 and the placebo groups, respectively, at the femoral neck by 1.5 ± 3.5% and 1.0 ± 5.0% in the MK-7 and the placebo groups, respectively, and at the lumbar spine by 1.8 ± 3.9% and 1.1 ± 3.1% in the MK-7 and the placebo groups, respectively. Changes in bone turnover markers were also similar between the two groups.We have previously reported improved microarchitecture with MK-7 after 1year. However, changes in microstructure over 3years were similar between the two groups, as assessed by both HRpQCT and DXA trabecular bone score. Treatment with MK-7375μg daily as an add-on to calcium and vitamin D increased carboxylation of osteocalcin. However, treatment of postmenopausal women with osteopenia for 3years did not affect biochemical markers of bone turnover, bone mineral density, or bone microarchitecture. The study was registered at Clinicaltrial.gov : NCT01922804 .

Erişkin hastalarda genel ve rejyonel anestezinin kemik belirteçleri ve kırık iyileşmesi üzerine uzun dönem etkileri

Purpose: Bone metabolism can be monitored quantitatively by measuring bone turnover markers in serum and/or urine. We aimed to investigate long-term effect of the type of the anesthesia on bone turnover markers and fracture healingMaterials and Methods:Thirty patients with American Society of Anesthesiologist physical status I-II whom were aged 40-70 years, scheduled for hip fracture were recruited. Patients were divided into the two groups as general anesthesia and regional anesthesia. Only morphine and tramadol were used for postoperative analgesia till the 12th weeks. Serum bone-specific alkaline phosphatase, osteocalcine, β-C terminal telopeptide and urine β-C terminal telopeptide levels were measured at preoperative, 4.th week and 12.th week of fracture. Results:A total of 25 patients were eligible for the study. There were no statistically significant between groups for values of bone turnover markers at the time point of preoperative, 4.th and 12.th weeks. With using linear regression analysis, serum β-CTX levels at 12.th week can be predict by 4.th weeks β-CTX levels (R2: 0.944) and urine β-CTX levels at 12.th week can be predicted by first week level.Conclusion: This pilot study showed that both general and regional anesthesia has similar effect on bone turnover markers and fracture healing.

Excessive Vitamin E Intake Does Not Cause Bone Loss in Male or Ovariectomized Female Mice Fed Normal or High-Fat Diets

Background: Animal studies on the effects of vitamin E on bone health have yielded conflicting and inconclusive results, and to our knowledge, no studies have addressed the effect of vitamin E on bone in animals consuming a high-fat diet (HFD).Objective: This study aimed to evaluate the effect of excessive vitamin E on bone metabolism in normal male mice and ovariectomized female mice fed a normal diet (ND) or HFD.Methods: In the first 2 experiments, 7-wk-old male mice were fed an ND (16% energy from fat) containing 75 (control), 0 (vitamin E-free), or 1000 (high vitamin E) mg vitamin E/kg (experiment 1) or an HFD (46% energy from fat) containing 0, 200, 500, or 1000 mg vitamin E/kg (experiment 2) for 18 wk. In the third experiment, 7-wk-old sham-operated or ovariectomized female mice were fed the ND (75 mg vitamin E/kg) or HFD containing 0 or 1000 mg vitamin E/kg for 8 wk. At the end of the feeding period, blood and femurs were collected to measure bone turnover markers and analyze histology and microcomputed tomography.Results: In experiments 1 and 2, vitamin E intake had no effect on plasma alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP) activity, or bone formation, resorption, or volume in femurs in mice fed the ND or HFDs. In experiment 3, bone volume was significantly reduced (85%) in ovariectomized mice compared with that in sham-operated mice (P < 0.05), but it did not differ among mice fed the 3 diets. Plasma ALP and TRAP activities and bone formation and resorption in femur were similar among ovariectomized mice fed the HFD containing 0 or 1000 mg vitamin E/kg.Conclusions: The results suggest that excess vitamin E intake does not cause bone loss in normal male mice or in ovariectomized or sham-operated female mice, regardless of dietary fat content.

Vitamin D levels in a large Mediterranean cohort: reconsidering normal cut-off values.

The determination of the normal range of 25-hydroxyvitamin D [25-(OH)D], though currently based on suppression of PTH levels, still remains a controversial issue. The 25-(OH)D levels exhibit gender and seasonal variability, the latter attributed in part to changes of insolation. The aim of this cross-sectional study was to estimate the levels of 25-(OH)D on the island of Crete and their correlation with metabolic, hormonal and bone turnover parameters. The study was performed over a period of five years and involved 8,183 male and female individuals (8,042 analyzed). Our results are as follows: (1) 25-(OH)D was significantly lower than expected (19.48±9.51 and 18.01±9.01 (ng/mL+SD) in males and females, respectively); (2) seasonal variation of 25-(OH)D was observed in both sexes (females < males), with values peaking in August; (3) a decline of 25-(OH)D was evident with advancing age, with lower levels in females compared to males up to menopause and no apparent difference between the genders thereafter; (4) levels of 25-(OH)D were lower in renal function impairment, diabetes/insulin resistance and inflammation, while no correlation was detectable in thyroid dysfunction; (5) normalization of PTH levels was observed at ~20 ng/mL 25-(OH)D. At the same cut-off level, a significant decrease of all measured bone turnover indices (b-ALP, osteocalcin and CTX) was evident. Based on the above data, it appears that a cut-off level of 25-(OH)D close to 20 ng/mL better reflects the physiology of our population.

Thyrotropin serum levels are differentially associated with biochemical markers of bone turnover and stiffness in women and men: results from the SHIP cohorts.

In two large German population-based cohorts, we showed positive associations between serum thyrotropin (TSH) concentrations and the Fracture Risk Assessment score (FRAX) in men and positive associations between TSH concentrations and bone turnover markers in women. The role of thyroid hormones on bone stiffness and turnover is poorly defined. Existing studies are confounded by differences in design and small sample size. We assessed the association between TSH serum concentrations and bone stiffness and turnover in the SHIP cohorts, which are two population-based cohorts from a region in Northern Germany comprising 2654 men and women and 3261 men and women, respectively. We calculated the bone stiffness index using quantitative ultrasound (QUS) at the calcaneus, employed FRAX score for assessment of major osteoporotic fractures, and measured bone turnover markers, N-terminal propeptide of type I procollagen (P1NP), bone-specific alkaline phosphatase (BAP), osteocalcin, and type I collagen cross-linked C-telopeptide (CTX) in all subjects and sclerostin in a representative subgroup. There was no association between TSH concentrations and the stiffness index in both genders. In men, TSH correlated positively with the FRAX score both over the whole TSH range (p < 0.01) and within the reference TSH range (p < 0.01). There were positive associations between TSH concentrations and P1NP, BAP, osteocalcin, and CTX (p < 0.01) in women but not in men. There was no significant association between TSH and sclerostin levels. TSH serum concentrations are associated with gender-specific changes in bone turnover and stiffness.

P236 Relationship Between Bone Mineral Density And Bone Turnover Markers In Severe Asthma Patients On Systemic Corticosteroids

Objectives Measure bone turnover markers (BTM) CTx, P1NP and bone-specific alkaline phosphatase (BsALP) in a severe asthma population using systemic corticosteroids (SCS). Assess bone mineral density (BMD) change in regional severe asthma clinics. Background Severe asthma often requires regular SCS use. SCS cause several adverse effects including reduced bone metabolism; resorption is increased and formation is decreased resulting in osteoporosis. DXA scans monitor BMD in the hip and spine every 3–5 years. BMD decrease is treated with bone sparing medication (BSM), but treatment is retrospective and response takes years to assess. BTM represent markers of systemic bone metabolism and may offer a more efficient alternative. CTx is a resorption marker, P1NP and BsALP are formation markers. Method Patients attending Manchester or Belfast severe asthma clinic with two or more DXA scans were identified from case files. We measured BTM in Manchester severe asthma patients and a control group of Manchester severe asthma patients requiring less than 3 courses of steroids per year. Using case files we collected data including DXA scan results, SCS use and osteoporosis risk factors. Results BMD change and BTM did not correlate overall (patients n = 78, controls n = 18) but correlated negatively in patients where the most recent DXA was Conclusion This study has confirmed that BTM may be potentially used as a surrogate for BMD measurement; however a more a prospective study where BTM are measured at the time of two DXA scans which are years apart is required.

The association between critical illness and changes in bone turnover in adults: a systematic review.

Critical illness may lead to altered bone turnover and associated adverse health outcomes. This systematic review found moderate evidence for a positive association between critical illness and increased bone turnover. Prospective cohort studies that identify the extent and risk factors for critical illness related bone loss are required. Intensive care patients face health issues that extend beyond their critical illness and result in significant morbidity and mortality. Critical illness may result in altered bone turnover due to associated immobilisation, inflammation, exposure to medications that effect bone and calcium metabolism, and endocrine dysfunction. The aim of this study was to synthesise the existing evidence for altered bone turnover in adults admitted to intensive care. A literature search using MEDLINE and EMBASE was performed from 1965 to March 2013. Reviewed studies investigated the relationship between critical illness and evidence of altered bone turnover (bone turnover markers, bone mineral density, or fracture). Studies were rated upon their methodological quality, and a best-evidence synthesis was used to summarise the results. Four cohort and seven case-control studies were identified for inclusion, of which five studies were rated as being of higher methodological quality. Ten of the studies measured bone turnover markers, and one study fracture rate. Findings were consistent across studies, and best-evidence analysis resulted in a conclusion that moderate evidence exists for an association between critical illness requiring admission to intensive care and altered bone turnover. A positive association between critical illness requiring intensive care admission and bone turnover exists, although data are limited, and the risk factors and the nature of the relationship are not yet understood. Prospective cohort studies that identify risk factors and extent of critical illness related bone turnover changes are required.

Relationships between age-related biochemical markers of bone turnover and OPG, TGF-β1 and TGF-β2 in native Chinese women

Osteoprotegerin (OPG), transforming growth factor-β1 (TGF-β1) and TGF-β2 are cytokines closely associated with bone metabolism. However, their association with bone turnover markers in native Chinese women remains unknown. The study aims to investigate the relationship between bone metabolism related cytokines including OPG, TGF-β1, TGF-β2 and bone turnover markers in native Chinese women. The cross-sectional study was conducted on 691 healthy Chinese women (20–80 years old). Levels of OPG, TGF-β1, TGF-β2, serum bone-specific alkaline phosphatase (BAP), osteocalcin (OC), cross-linked N-terminal telopeptides of type I collagen (sNTX), cross-linked C-terminal telopeptides of type I collagen (sCTX), urinary NTX (uNTX), urinary CTX (uCTX) and total urinary deoxypyridinoline (uDPD) were determined. The present study showed that OPG and TGF-β2 had positive correlation with BAP, OC, uNTX, uCTX and uDPD, while TGF-β1 showed negative correlation with BAP, OC, sCTX, uNTX and uCTX, and most of the coefficients of partial correlation remained significant after adjustments for age and body mass index (BMI). Multiple linear regression stepwise analysis showed that OPG and TGF-β2 were positive determinative factors for BAP, sCTX, uNTX and uCTX, which could explain 0.6–16.6% of the variation in these markers. TGF-β1 was a negative determinative factor for BAP, OC, sCTX and uCTX, which could explain 0.7–7.3% of the variation in these markers. This study suggested that measuring bone turnover indicators and serum cytokines simultaneously might help evaluating changes in bone turnover rate caused by aging or menopause in women.

Decreased Bone Turnover Markers in Children on Long‐Term Parenteral Nutrition (PN) for Intestinal Failure (IF)

Metabolic bone disease (MBD) is a well-recognized but poorly understood complication of long-term parenteral nutrition (PN). Bone histomorphometry in adults has provided useful information but does not provide quantitative measures of bone resorption and is to invasive for children. Measurement of bone turnover markers provides an alternative less invasive approach. We therefore aimed to measure bone turnover markers in children on long-term PN for intestinal failure (IF), and to compare them to age- and gender-matched controls. Serum concentrations of osteocalcin (OC), bone-specific alkaline phosphatase (BSAP), and c-telopeptide (CTx) were measured in IF patients treated at a multidisciplinary intestinal rehabilitation and home PN program at the Hospital for Sick Children, Toronto, Canada. Age- and gender-matched control participants were recruited for comparison. A total of 13 IF patients and 20 control participants were recruited. IF patients had lower serum OC and CTx concentrations when compared with controls: 42.43 ± 11.54 vs 68.39 ± 20.95 µg/L (P < .01) and 7.454 ± 2.17 vs 9.246 ± 1.92 (P < .05; mean ± SD) µg/L for OC and CTx, respectively. In a subgroup of 9 IF patients for whom BMD was available, OC and CTx concentration were negatively correlated to BMD (g/cm(2)) and BMD z score. Bone turnover markers may be useful indicators for identifying children on long-term PN at risk of MBD. Further studies are needed to validate the current results and determine the factors that influence the occurrence and evolution of MBD in children on PN.