Markers of bone resorption predict hip fracture in elderly women: the EPIDOS Prospective Study

Unveiling novel metabolic alterations in postmenopausal osteoporosis and type 2 diabetes mellitus through NMR-based metabolomics: A pioneering approach for identifying early diagnostic markers

BACKGROUND AND AIMS

Postmenopausal osteoporosis (PMO) and type 2 diabetes mellitus (T2DM) frequently coexist in postmenopausal women. The study aimed to explore metabolic variations linked to these circumstances and their simultaneous presence through proton nuclear magnetic resonance metabolomics (1H NMR).

MATERIALS AND METHODS

Serum samples from 80 postmenopausal women, including 20 PMO individuals, 20 T2DM, 20 T2DM + PMO, and 20 healthy postmenopausal women, were analyzed using 1H NMR spectroscopy.

RESULTS

Our study revealed significant metabolic profile differences among the four groups. Notably, the T2DM + PMO group showed elevated levels of alanine, pyruvate, glutamate, lactate, and aspartate, indicating their involvement in lipid metabolism, energy, and amino acids. Importantly, our multivariate statistical analysis identified a metabolite set that accurately distinguished the groups, suggesting its potential as an early diagnostic marker.

CONCLUSION

The 1H NMR metabolomics approach uncovered metabolic biomarkers intricately linked to postmenopausal osteoporosis (PMO), type 2 diabetes mellitus (T2DM), and their concurrent presence. Among these biomarkers, alanine emerged as a pivotal player, showing its significant role in the metabolic landscape associated with PMO and T2DM. These findings shed light on the pathophysiological mechanisms underlying these conditions and underscore alanine's potential as a diagnostic biomarker.

[Bone metabolism in patients evaluated for lung transplantation]

Introduction

Introduction: the prevalence of osteoporosis among candidates for lung transplantation is high and its pathophysiology is multifactorial. Objectives: to evaluate differences in bone mineral density, risk of fractures and bone remodeling markers in patients with terminal lung disease, at the time they are evaluated for lung transplantation, comparing two types of pathologies. Material and methods: fifty-nine subjects, proposed to receive a lung transplant due to advanced lung disease, were included in this study. They were divided into two groups according to their respiratory pathology: chronic obstructive pulmonary disease (COPD) and diffuse interstitial pulmonary disease (ILD). Demographic data were collected and bone densitometry, blood analysis with markers of bone remodeling, spirometry, six-minute walk test (6MWT), echocardiography and cardiac catheterization were performed Results: no differences were found between the groups, regarding their age, sex, BMI or exposure to tobacco. A higher prevalence of osteoporosis and a higher FRAX were observed in the group with COPD. Regarding bone remodeling markers, higher parathyroid hormone (PTH) and higher osteocalcin were found in the COPD group. Vitamin D was lower in COPD patients. Conclusions: two out of three of the patients evaluated for lung transplantation had osteopenia or osteoporosis. The prevalence of osteoporosis and FRAX is higher in COPD patients. Vitamin D supplementation should be considered in certain patients. Differences in bone remodeling markers may be useful for suspected osteoporosis and therapeutic management.

Pre-treatment bone turnover does not influence the level of the response to alendronate in postmenopausal osteoporosis at the bone tissue level

PURPOSE

The main effect of anti-resorptive agents such as bisphosphonates is a reduction of bone resorption, with a consequent marked decrease of bone turnover. This post-hoc analysis investigated the changes of histomorphometric parameters of bone turnover after alendronate (ALN), according to the baseline turnover.

METHODS

Ninety postmenopausal women underwent a transiliac bone biopsy before and after 6 (n = 44) or 12 (n = 46) months of treatment with ALN (70 mg/week). The dynamic parameters reflecting the bone formation and bone turnover were mineralizing surface (MS/BS; %), bone formation rate (BFR/BS; μm3/μm2/d), and activation frequency (Ac.f; /yr). Biochemical markers sPINP and the sCTX were assessed before treatment and after 3, 6, and 12 months. Subjects were divided into quartiles based on the baseline values of BFR/BS.

RESULTS

At baseline, MS/BS and Ac.f were significantly different (p < 0.0001) among the BFR quartiles. sCTX and sP1NP were not significantly different among quartiles. After ALN treatment, MS/BS was not significantly different among quartiles but Ac.f remained significantly lower in the first quartile compared to the third and fourth ones (p < 0.03). The absolute value of the difference between pre- and post-treatment significantly correlated with the baseline BFR/BS but when expressed in percent of the baseline value, the magnitude of the diminutions of MS/BS, Ac.f, sCTX, and sP1NP was similar in the four baseline BFR quartiles.

CONCLUSION

The percentage response to ALN appeared independent of the baseline level of bone turnover. After treatment, the bone turnover tended to be similar in all BFR quartiles. This analysis investigated the influence of baseline turnover measured by bone histomorphometry on the effect of alendronate. When expressed in percent of pre-treatment values, the decreases of histomorphometric parameters and biochemical markers of bone turnover were independent of the baseline turnover.

A new serum biochemical marker of synovium turnover predicts radiographic progression in patients with early arthritis

OBJECTIVE

To investigate whether serum Col 3-4, a new biochemical marker of synovial tissue turnover, was associated with progression of joint damage in patients with early arthritis.

METHODS

A total of 788 early arthritis patients (<6 months of symptoms, 82% diagnosis of RA, 18% undifferentiated arthritis) from the prospective ESPOIR study were investigated. Progression was defined as an increase of 1 or 5 unit(s) in radiographic van der Heijde modified Sharp score between baseline and 1 or 5 years, respectively. Associations between baseline Col 3-4 and progression were assessed by logistic regression.

RESULTS

Each standard deviation increase of baseline Col 3-4 levels was associated with an increased 5-yr total damage progression with an odds ratio (OR, 95% CI) of 1.51 (1.21, 1.88), which remained significant when DAS28, C-reactive protein and anti-citrullinated protein antibodies positivity were included in the model [OR (95% CI): 1.34 (1.01, 1.76)]. Further adjustment for bone erosion did not modify the association. Patients with both Col 3-4 in the highest quintile and bone erosion had a >2-fold higher risk of progression [OR (95% CI): 7.16 (2.31, 22)] than patients with either high Col 3-4 [2.91 (1.79, 4.73)] or bone erosion [2.36 (2.38, 3.70)] alone. Similar associations were observed for prediction of 12 months progression.

CONCLUSIONS

Increased serum Col 3-4 is associated with a higher risk of structural progression, independently of major risk factors. Col 3-4 may be useful in association with bone erosion to identify patients with early arthritis at higher risk.

The Use of Bone-Turnover Markers in Asia-Pacific Populations

Bone-turnover marker (BTM) measurements in the blood or urine reflect the bone-remodeling rate and may be useful for studying and clinically managing metabolic bone diseases. Substantial evidence supporting the diagnostic use of BTMs has accumulated in recent years, together with the publication of several guidelines. Most clinical trials and observational and reference-interval studies have been performed in the Northern Hemisphere and have mainly involved Caucasian populations. This review focuses on the available data for populations from the Asia-Pacific region and offers guidance for using BTMs as diagnostic biomarkers in these populations. The procollagen I N-terminal propeptide and β-isomerized C-terminal telopeptide of type-I collagen (measured in plasma) are reference BTMs used for investigating osteoporosis in clinical settings. Premenopausal reference intervals (established for use with Asia-Pacific populations) and reference change values and treatment targets (used to monitor osteoporosis treatment) help guide the management of osteoporosis. Measuring BTMs that are not affected by renal failure, such as the bone-specific isoenzyme alkaline phosphatase and tartrate-resistant acid phosphatase 5b, may be advantageous for patients with advanced chronic kidney disease. Further studies of the use of BTMs in individuals with metabolic bone disease, coupled with the harmonization of commercial assays to provide equivalent results, will further enhance their clinical applications.

Osteoporosis: Investigations and Monitoring

Background

Osteoporosis is characterized by microarchitectural disruption of the bone, decrease in bone mineral density, and increased skeletal fragility and risk of fracture. Osteoporosis occurs due to the decoupling of bone formation and bone resorption, with a significant increase in resorption. This review article focuses on the role of laboratory investigations in the diagnosis and monitoring of treatment in patients with osteoporosis.

Methods

This review article collected literature from various databases using keywords such as 'Laboratory investigations', 'Osteoporosis', 'Diagnosis', 'Monitoring', and 'Bone turnover markers'.

Results and Discussion

Laboratory investigations, including serum calcium, alkaline phosphatase, vitamin D, and parathormone, are commonly performed tests to exclude secondary causes of osteoporosis and monitor the response to therapy. The biochemical markers of bone turnover are newly emerged tests for monitoring individual patients with osteoporosis. These markers are classified as bone formation and resorption markers, measurable in both serum and urine. The use of these markers is limited by biological and analytical variability. The International Federation of Clinical Chemistry and Laboratory Medicine and the International Osteoporosis Foundation recommend serum procollagen type 1 amino-terminal propeptide as the bone formation marker and β-form of C-terminal cross-linked telopeptide of type I collagen (β-CTx-1/β-CrossLaps) as the marker of choice, using standardized procedures. However, in specific cases, such as patients with chronic renal disease, CTx-1 is replaced by the resorption marker tartrate-resistant acid phosphatase 5b, as its levels are not affected by renal excretion.

Conclusion

Bone turnover markers have emerged as tools for the assessment of osteoporosis, using standardized procedures, and are useful in monitoring therapy and treatment compliance.

Correlation between bone mineral density and bone metabolic markers in postmenopausal women with osteoporotic fractures at different C-terminal telopeptide of type 1 collagen levels: a retrospective analysis study

OBJECTIVE

This study aimed to analyze the correlation between bone mineral density (BMD) and bone resorption markers in postmenopausal women with osteoporosis fractures and identify risk factors for second fractures.

METHODS

This retrospective analysis of 1,239 older women with fractures with a median age of 70 years who attended Shanghai General Hospital from January 2007 to December 2016, included a first fracture group (1,008 cases) and a second fractures group (231 cases). The risk factors for fractures were analyzed by comparing these groups on clinical characteristics, BMD, and bone metabolism markers stratified by quartiles of serum C-terminal telopeptide of type 1 collagen (CTX). Binary logistic regression analysis was used to identify risk factors for second fractures.

RESULTS

In the whole sample, BMD was negatively correlated with age and serum osteocalcin and positively correlated with body mass index (BMI). In women with first fractures, those in the highest quartile of serum CTX had the lowest spine and hip BMD. Second fractures were significantly associated with BMI, lower spine and hip BMD, and higher serum osteocalcin but not CTX. Binary logistic regression analysis showed that high BMI (odds ratio [OR], 1.08 [95% CI, 1.03-1.14]; P = 0.001), low lumbar BMD (OR, 0.24 [95% CI, 0.07-0.82]; P = 0.023), low total hip BMD (OR, 0.05 [95% CI, 0.00-0.88]; P = 0.041), and lack of antiosteoporosis treatment (OR, 2.71 [95% CI, 2.71-4.08]; P < 0.001) were independent risk factors for second fractures.

CONCLUSIONS

In older women with fractures, BMD was significantly lower in women with second fractures than in those with first fractures. Higher levels of serum CTX and osteocalcin, which indicates increased bone resorption, were negatively correlated with BMD. In women with a first fracture, serum CTX higher than 605 pg/mL was negatively correlated with BMD, whereas no correlation was found between different CTX and BMD in women with second fractures. High BMI and low BMD as well as not receiving antiosteoporosis treatment were independent risk factors for second fractures.

Proceedings of the 2023 Santa Fe Bone Symposium: Progress and Controversies in the Management of Patients with Skeletal Diseases

The Santa Fe Bone Symposium (SFBS) held its 23rd annual event on August 5-6, 2023, in Santa Fe, New Mexico, USA. Attendees participated in-person and remotely, representing many states and countries. The program included plenary presentations, panel discussions, satellite symposia, a Project ECHO workshop, and a session on healthcare policy and reimbursement for fracture liaison programs. A broad range of topics were addressed, including transitions of osteoporosis treatments over a lifetime; controversies in vitamin D; update on Official Positions of the International Society for Clinical Densitometry; spine surgery and bone health; clinical applications of bone turnover markers; basic bone biology for clinicians; premenopausal-, pregnancy-, and lactation-associated osteoporosis; cancer treatment induced bone loss in patients with breast cancer and prostate cancer; genetic testing for skeletal diseases; and an update on nutrition and bone health. There were also sessions on rare bone diseases, including managing patients with hypophosphatasia; treatment of X-linked hypophosphatemia; and assessment and treatment of patients with hypoparathyroidism. There were oral presentations of abstracts by endocrinology fellows selected from those who participated in the Santa Fe Fellows Workshop on Metabolic Bone Diseases, held the 2 days prior to the SFBS. These proceedings of the 2023 SFBS present the clinical highlights and insights generated from many formal and informal discussions in Santa Fe.

[Diagnosis and treatment of osteoporosis in patients with chronic kidney disease : Joint guidelines of the Austrian Society for Bone and Mineral Research (ÖGKM), the Austrian Society of Physical and Rehabilitation Medicine (ÖGPMR) and the Austrian Society of Nephrology (ÖGN)]

DEFINITION AND EPIDEMIOLOGY

Chronic kidney disease (CKD): abnormalities of kidney structure or function, present for over 3 months. Staging of CKD is based on GFR and albuminuria (not graded). Osteoporosis: compromised bone strength (low bone mass, disturbance of microarchitecture) predisposing to fracture. By definition, osteoporosis is diagnosed if the bone mineral density T‑score is ≤ -2.5. Furthermore, osteoporosis is diagnosed if a low-trauma (inadequate trauma) fracture occurs, irrespective of the measured T‑score (not graded). The prevalence of osteoporosis, osteoporotic fractures and CKD is increasing worldwide (not graded). PATHOPHYSIOLOGY, DIAGNOSIS AND TREATMENT OF CHRONIC KIDNEY DISEASE-MINERAL AND BONE DISORDER (CKD-MBD): Definition of CKD-MBD: a systemic disorder of mineral and bone metabolism due to CKD manifested by either one or a combination of the following: abnormalities of calcium, phosphorus, PTH, or vitamin D metabolism; renal osteodystrophy; vascular calcification (not graded). Increased, normal or decreased bone turnover can be found in renal osteodystrophy (not graded). Depending on CKD stage, routine monitoring of calcium, phosphorus, alkaline phosphatase, PTH and 25-OH-vitamin D is recommended (2C). Recommendations for treatment of CKD-MBD: Avoid hypercalcemia (1C). In cases of hyperphosphatemia, lower phosphorus towards normal range (2C). Keep PTH within or slightly above normal range (2D). Vitamin D deficiency should be avoided and treated when diagnosed (1C).

DIAGNOSIS AND RISK STRATIFICATION OF OSTEOPOROSIS IN CKD

Densitometry (using dual X‑ray absorptiometry, DXA): low T‑score correlates with increased fracture risk across all stages of CKD (not graded). A decrease of the T‑score by 1 unit approximately doubles the risk for osteoporotic fracture (not graded). A T-score ≥ -2.5 does not exclude osteoporosis (not graded). Bone mineral density of the lumbar spine measured by DXA can be increased and therefore should not be used for the diagnosis or monitoring of osteoporosis in the presence of aortic calcification, osteophytes or vertebral fracture (not graded). FRAX can be used to aid fracture risk estimation in all stages of CKD (1C). Bone turnover markers can be measured in individual cases to monitor treatment (2D). Bone biopsy may be considered in individual cases, especially in patients with CKD G5 (eGFR < 15 ml/min/1.73 m2) or CKD 5D (dialysis).

SPECIFIC TREATMENT OF OSTEOPOROSIS IN PATIENTS WITH CKD

Hypocalcemia should be treated and serum calcium normalized before initiating osteoporosis therapy (1C). CKD G1-G2 (eGFR ≥ 60 ml/min/1.73 m2): treat osteoporosis as recommended for the general population (1A). CKD G3-G5D (eGFR < 60 ml/min/1.73 m2 to dialysis): treat CKD-MBD first before initiating osteoporosis treatment (2C). CKD G3 (eGFR 30-59 ml/min/1.73 m2) with PTH within normal limits and osteoporotic fracture and/or high fracture risk according to FRAX: treat osteoporosis as recommended for the general population (2B). CKD G4-5 (eGFR < 30 ml/min/1.73 m2) with osteoporotic fracture (secondary prevention): Individualized treatment of osteoporosis is recommended (2C). CKD G4-5 (eGFR < 30 ml/min/1.73 m2) and high fracture risk (e.g. FRAX score > 20% for a major osteoporotic fracture or > 5% for hip fracture) but without prevalent osteoporotic fracture (primary prevention): treatment of osteoporosis may be considered and initiated individually (2D). CKD G4-5D (eGFR < 30 ml/min/1.73 m2 to dialysis): Calcium should be measured 1-2 weeks after initiation of antiresorptive therapy (1C).

PHYSICAL MEDICINE AND REHABILITATION

Resistance training prioritizing major muscle groups thrice weekly (1B). Aerobic exercise training for 40 min four times per week (1B). Coordination and balance exercises thrice weekly (1B). Flexibility exercise 3-7 times per week (1B).

Total hip arthroplasty versus hemiarthroplasty in the treatment of active elderly patients over 75 years with displaced femoral neck fractures: a retrospective study

BACKGROUND

Femoral neck fractures are associated with substantial morbidity and mortality for older adults. Total hip arthroplasty (THA) and hemiarthroplasty (HA) are widely used in elderly patients with displaced femoral neck fractures (DFNF), but there is still controversy refering to the optimal chose for the management of DFNF in active elderly patients.

METHODS

This is a retrospective cohort study that incorporates medical record review with an outcomes management database. 73 patients who underwent HA and 66 patients who underwent THA were identified from January 2015 to December 2017. Data of age, gender, BMI, comorbidity status, operation time, blood loss, hospitalization time, in-hospital complication were collected and analyzed. Clinical follow-up and radiographic examinations were performed at approximately five years, and hip complications, Harris Hip Score (HHS) and EuroQol-5 Dimensions (EQ-5D) were assessed.

RESULTS

Preoperative general data of sex, age, BMI and charlson comorbidity score of THA group(n=55) has no statistically significant difference with that of HA group. Patients treated by THA had significantly longer operation time (105.5 vs 76.7 minutes; P < 0.001), more blood loss (524.1 vs 350.1 ml; P < 0.001) and longer hospitalization time (15.8 vs 13.8 days; P < 0.001). There was no significant differences between two groups in complications (32.7% vs 25.8%, P=0.432). No patients died during the hospitalization. After five years, only 33 patients in the THA group and 34 patents in the HA group were still alive, and the fraction surviving were not statistically significant between two groups (60.0% vs 54.8%, P> 0.05). The differences in hip function in favor of THA appeared to increase after the five-year follow-up, and the difference was significant in terms of the total Harris hip score (81.3 vs 73.1, P < 0.001) as well as in the dimensions of pain (38.9 vs 35.9, P=0.033), function (33.7 vs 29.2, P=0.001), absence of deformity (4.0 vs 3.9, P=0.023) and range of motion (4.6 vs 4.2, P=0.008). There was no significant differences between groups in hip dislocation rate (6.1% vs 0.0%, P=0.239). The erosion rate of hip joint in the THA group was significantly lower than that of the HA group (0.0% vs 26.5%, P=0.002). The health-related quality of life, according to EQ-5D index score, was found to be higher (0.69 vs 0.63, P= 0.001) in the THA group than the HA group after five years.

CONCLUSION

THA may be a preferred management option for active elderly patients over 75 years. The more extensive surgery of THA is not associated with higher in-hospital complication rate or mortality rate. These patients can benefit from THA in terms of hip function and quality of life.

TRIAL REGISTRATION

No.

Effect of chemotherapy and different chemotherapy regimens on bone health among Chinese breast cancer women in different menstrual status: a self-control study

PURPOSE

Although the therapy-related bone loss attracts increasing attention nowadays, the differences in chemotherapy-induced bone loss and bone metabolism indexes change among breast cancer (BC) women with different menstrual statuses or chemotherapy regimens are unknown. The aim of the study is to explore the effects of different regimens of chemotherapy on bone health.

METHOD

The self-control study enrolled 118 initially diagnosed BC women without distant metastasis who underwent dual-energy X-ray absorptiometry (DXA) bone mineral density (BMD) screening and (or) bone metabolism index monitoring during chemotherapy at Chongqing Breast Cancer Center. Mann-Whitney U test, Cochran's Q test, and Wilcoxon sign rank test were performed.

RESULTS

After chemotherapy, the BMD in the lumbar 1-4 and whole lumbar statistically decreased (- 1.8%/per 6 months), leading to a significantly increased proportion of osteoporosis (27.1% vs. 20.5%, P < 0.05), which were mainly seen in the premenopausal group (- 7.0%/per 6 months). Of the chemotherapeutic regimens of EC (epirubicin + cyclophosphamide), TC (docetaxel + cyclophosphamide), TEC (docetaxel + epirubicin + cyclophosphamide), and EC-T(H) [epirubicin + cyclophosphamide-docetaxel and/or trastuzumab], EC regimen had the least adverse impact on BMD, while the EC-TH regimen reduced BMD most (P < 0.05) inspite of the non-statistical difference between EC-T regimen, which was mainly seen in the postmenopausal group. Chemotherapy-induced amenorrhea (estradiol 94 pg/ml vs, 22 pg/ml; FSH 9.33 mIU/ml vs. 61.27 mIU/ml) was proved in premenopausal subgroup (P < 0.001). Except the postmenopausal population with calcium/VitD supplement, the albumin-adjusted calcium increased significantly (2.21 mmol/l vs. 2.33 mmol/l, P < 0.05) after chemotherapy. In postmenopausal group with calcium/VitD supplement, β-CTX decreased significantly (0.56 ng/ml vs. 0.39 ng/ml, P < 0.05) and BMD were not affected by chemotherapy (P > 0. 05). In premenopausal group with calcium/VitD supplement, PTH decreased significantly (52.90 pg/ml vs. 28.80 pg/ml, P = 0. 008) and hip BMD increased after chemotherapy (0.845 g/m2 vs. 0.952 g/m2, P = 0. 006). As for both postmenopausal and premenopausal group without calcium/VitD supplement, there was a significant decrease in bone mass in hip and lumbar vertebrae after chemotherapy (0.831 g/m2 vs. 0.776 g/m2; 0.895 g/m2 vs. 0.870 g/m2, P < 0.05).

CONCLUSION

Chemotherapy might induce lumbar vertebrae BMD loss and spine osteoporosis with regimen differences among Chinese BC patients. Calcium/VitD supplementation could improve bone turnover markers, bone metabolism indicators, and bone mineral density. Early interventions on bone health are needed for BC patients during chemotherapy.

Effects of Microfiltered Seawater Intake and Variable Resistance Training on Strength, Bone Health, Body Composition, and Quality of Life in Older Women: A 32-Week Randomized, Double-Blinded, Placebo-Controlled Trial

The aim was to explore the effects of a 32-week resistance training (RT) intervention with elastic bands with or without microfiltered seawater (SW) supplementation on isokinetic strength, bone mineral density (BMD), body composition, and subjective quality of life in postmenopausal women. Ninety-three untrained women (age: 70.00 ± 6.26 years; body mass index: 22.05 ± 3.20 kg/m²; body fat: 37.77 ± 6.38%; 6.66 ± 1.01 s up-and-go test) voluntarily participated in this randomized, double-blinded, controlled trial. Participants were allocated into four groups (RT+SW, RT+PLA, CON+SW, and CON+PLA). The RT intervention (twice weekly) consisted of different exercises for the whole body performed at submaximal intensities with elastic bands. Both control groups were not involved in any exercise program. A two-way mixed analysis of variance of repeated measures revealed significant improvements in almost all the variables in both intervention groups (p < 0.05). However, significant differences with controls were encountered in isokinetic strength, body fat percentage, and bodily pain. Although the group with SW supplementation obtained greater effect sizes, non-significant differences between both RT groups were observed. In conclusion, the determinant factor of the adaptations seems to be RT rather than SW.

The use of alkaline phosphatase as a bone turnover marker after spinal cord injury: A scoping review of human and animal studies

BACKGROUND

Serum alkaline phosphatase (ALP) is measured as an indicator of bone or liver disease. Bone-specific alkaline phosphatase (B-ALP) is an isoform of ALP found in the bone tissue which can predict fractures and heterotopic ossification.

OBJECTIVE

The aim of this scoping review was to explore the current use of ALP and B-ALP in studies using humans or animal models of SCI, and to identify ways to advance future research using ALP and B-ALP as a bone marker after SCI.

RESULTS

HUMAN STUDIES: 42 studies were included. The evidence regarding changes or differences in ALP levels in individuals with SCI compared to controls is conflicting. For example, a negative correlation between B-ALP and total femur BMD was observed in only one of three studies examining the association. B-ALP seemed to increase after administration of teriparatide, and to decrease after treatment with denosumab. The effects of exercise on ALP and B-ALP levels are heterogeneous and depend on the type of exercise performed. ANIMAL STUDIES: 11 studies were included. There is uncertainty regarding the response of ALP or B-ALP levels after SCI; levels increased after some interventions, including vibration protocols, curcumin supplementation, cycles in electromagnetic field or hyperbaric chamber. Calcitonin or bisphosphonate administration did not affect ALP levels.

CONCLUSION

Researchers are encouraged to measure the bone-specific isoform of ALP rather than total ALP in future studies in humans of animal models of SCI.

Bone Turnover Markers and Osteokines in Adolescent Female Athletes of High- and Low-Impact Sports Compared With Nonathletic Controls

This study examined differences in resting concentrations of markers of bone formation and resorption, and osteokines between female adolescent (12-16 y) swimmers, soccer players, and nonathletic controls. Resting, morning blood samples were obtained after an overnight fast from 20 swimmers, 20 soccer players, and 20 nonathletic controls, matched for age. carboxyl-terminal cross-linking telopeptide of type I collagen (CTX), amino-terminal propeptide of type I collagen (P1NP), total osteocalcin (OC), sclerostin, osteoprotegerin (OPG), and receptor activator of nuclear factor kappa B ligand (RANKL) were analyzed in serum. After controlling for percent body fat, there were no significant differences between swimmers and nonathletic controls in any of the measured markers. In contrast, soccer players had significantly higher P1NP (89.5 [25.6] ng·mL-1), OC (57.6 [22.9] ng·mL-1), and OPG (1052.5 [612.6] pg·mL-1) compared with both swimmers (P1NP: 66.5 [20.9] ng·mL-1; OC: 24.9 [12.5] ng·mL-1; OPG: 275.2 [83.8] pg·mL-1) and controls (P1NP: 58.5 [16.2] ng·mL-1; OC: 23.2 [11.9] ng·mL-1; OPG: 265.4 [97.6] pg·mL-1), with no differences in CTX, sclerostin, and RANKL. These results suggest that bone formation is higher in adolescent females engaged in high-impact sports like soccer compared with swimmers and controls.

Quantitative lateral flow immunoassay for rapid detection of procollagen type I N-terminal propeptide in the monitoring of osteoporosis treatment

Appropriate follow-up after treatment initiation in patients with osteoporosis is challenging. Serum biomarkers may offer more efficient monitoring of bone mineral density (BMD) than the currently used dual X-ray absorptiometry; however, significant changes in BMD often occur over at least 12 months. During teriparatide treatment for osteoporosis, monitoring with markers such as procollagen type I propeptide (PINP), which is derived from osteoblasts, can provide clinically useful information for disease management. However, rapid and cost-effective methods for detecting serum PINP are lacking, necessitating a point-of-care test (POCT) for enhanced follow-up efficiency in osteoporosis management. For the quantitative detection of PINP, we developed a high-sensitivity lateral flow immunoassay with a stacking pad (sLFIA). We established a calibration equation based on the test line/control line ratio obtained from our PINP sLFIA results of various nonspiked serum samples to calculate the PINP concentrations in 40 serum samples and compared the result with those obtained using a fully automated electrochemiluminescence immunoassay. PINP concentrations between these two methods exhibited excellent correlation (R = 0.991). In addition, we assessed the serum PINP concentrations of patients with osteoporosis treated with teriparatide. At the 3-month follow-up, their PINP levels were nearly twice as high as those at baseline, thus implying that our method can be used for osteoporosis treatment monitoring. Our findings thus indicate that the PINP sLFIA can serve as a POCT for monitoring medication response and managing osteoporosis.

Emerging Role of 18F-NaF PET/Computed Tomographic Imaging in Osteoporosis: A Potential Upgrade to the Osteoporosis Toolbox

Osteoporosis is a metabolic bone disorder that leads to a decline in bone microarchitecture, predisposing individuals to catastrophic fractures. The current standard of care relies on detecting bone structural change; however, these methods largely miss the complex biologic forces that drive these structural changes and response to treatment. This review introduces sodium fluoride (18F-NaF) positron emission tomography/computed tomography (PET/CT) as a powerful tool to quantify bone metabolism. Here, we discuss the methods of 18F-NaF PET/CT, with a special focus on dynamic scans to quantify parameters relevant to bone health, and how these markers are relevant to osteoporosis.

Bone Turnover Markers: Basic Biology to Clinical Applications

Bone turnover markers (BTMs) are used widely, in both research and clinical practice. In the last 20 years, much experience has been gained in measurement and interpretation of these markers, which include commonly used bone formation markers bone alkaline phosphatase, osteocalcin, and procollagen I N-propeptide; and commonly used resorption markers serum C-telopeptides of type I collagen, urinary N-telopeptides of type I collagen and tartrate resistant acid phosphatase type 5b. BTMs are usually measured by enzyme-linked immunosorbent assay or automated immunoassay. Sources contributing to BTM variability include uncontrollable components (e.g., age, gender, ethnicity) and controllable components, particularly relating to collection conditions (e.g., fasting/feeding state, and timing relative to circadian rhythms, menstrual cycling, and exercise). Pregnancy, season, drugs, and recent fracture(s) can also affect BTMs. BTMs correlate with other methods of assessing bone turnover, such as bone biopsies and radiotracer kinetics; and can usefully contribute to diagnosis and management of several diseases such as osteoporosis, osteomalacia, Paget's disease, fibrous dysplasia, hypophosphatasia, primary hyperparathyroidism, and chronic kidney disease-mineral bone disorder.

Bone Turnover Marker Profiling and Fracture Risk in Older Women: Fracture Risk from Age 75 to 90

PURPOSE

A major challenge in osteoporosis is to identify individuals at high fracture risk. We investigated six bone turnover markers (BTMs) to determine association with specific fracture types; the time-frame for risk prediction and whether these are influenced by age at assessment.

METHODS

Population-based OPRA cohort (n = 1044) was assessed at ages 75, 80, 85 and fractures documented for up to 15 years. Six BTMs were analyzed at each time-point (N-terminal propeptide of type I collagen, PINP; total osteocalcin, OC; bone-specific alkaline phosphatase, BALP; C-terminal telopeptide of type I collagen, CTX; tartrate-resistant acid phosphatase 5b, TRAcP5b; urinary osteocalcin). Hazard ratios (HR) for any, major osteoporotic, vertebral and hip fractures were calculated as short (1, 2, 3 years) and long-term risk (5, 10, 15 years).

RESULTS

At 75 year, high CTX levels were associated with an increased risk of all fractures, including major osteoporotic fractures, across most time-frames (HRs ranging: 1.28 to 2.28). PINP was not consistently associated. Urinary osteocalcin was consistently associated with elevated short-term risk (HRs ranging: 1.83-2.72). Other BTMs were directionally in accordance, though not all statistically significant. BTMs were not predictive for hip fractures. Association of all BTMs attenuated over time; at 80 year none were associated with an increased fracture risk.

CONCLUSION

CTX, urinary OC and TRAcP5b are predictive for fracture in a 1 to 3 year, perspective, whereas in the long-term or above age 80 years, BTMs appear less valuable. Resorption markers, particularly CTX, were more consistently associated with fracture risk than formation markers in the very elderly.

Microgravity-Related Changes in Bone Density and Treatment Options: A Systematic Review

Space travelers are exposed to microgravity (µg), which induces enhanced bone loss compared to the age-related bone loss on Earth. Microgravity promotes an increased bone turnover, and this obstructs space exploration. This bone loss can be slowed down by exercise on treadmills or resistive apparatus. The objective of this systematic review is to provide a current overview of the state of the art of the field of bone loss in space and possible treatment options thereof. A total of 482 unique studies were searched through PubMed and Scopus, and 37 studies met the eligibility criteria. The studies showed that, despite increased bone formation during µg, the increase in bone resorption was greater. Different types of exercise and pharmacological treatments with bisphosphonates, RANKL antibody (receptor activator of nuclear factor κβ ligand antibody), proteasome inhibitor, pan-caspase inhibitor, and interleukin-6 monoclonal antibody decrease bone resorption and promote bone formation. Additionally, recombinant irisin, cell-free fat extract, cyclic mechanical stretch-treated bone mesenchymal stem cell-derived exosomes, and strontium-containing hydroxyapatite nanoparticles also show some positive effects on bone loss.

Global Research Status and Trends of Femoral Neck Fracture Over the Past 27 Years: A Historical Review and Bibliometric Analysis

Background

Femoral neck fracture (FNF) is a commonly encountered injury in orthopedic practice, and many studies have been conducted in this field. However, no bibliometric studies regarding the global research trend concerning FNF have been performed. This study aims to analyze the knowledge framework, research hotspots, and theme trends in the field of FNF research.

Methods

The scientific outputs related to FNF from 1994 to 2021 were retrieved from the Web of Science Core Collection. Three bibliometric tools were used for this study. The main analyses include publication and citation counts, contributions of countries, institutions, authors, funding agencies and journals, and clustering of keywords.

Results

In total, 3,553 articles were identified. The annual publication counts of FNF showed an ascending tendency as a whole. The United States has the most prominent contributions, with the most number of publications and the highest H-index. Karolinska Institutet devoted the most in this domain. Professors Bhandari M, Schemitsch EH, Frihagen F, Parker MJ, and Rogmark C were the core authors in this field. The most productive journal was Injury International Journal of the Care of the Injured. Keywords were divided into four clusters: epidemiology and mortality, fracture prevention, internal-fixation and risk factors, and hip replacement. A trend of balanced and diversified development existed in these clusters. Keywords with the ongoing bursts, including “outcome,” “reoperation,” “complication,” “revision,” “displaced intracapsular,” “fracture,” and “adult,” are considered as the research hotspots in the future and deserve more attention.

Conclusions

The management of FNF in young patients is drawing more attention from orthopedic surgeons, and it is expected that these research topics may continue to be the research hotspots and focus in the near future.

Management of patients at very high risk of osteoporotic fractures through sequential treatments

Osteoporosis care has evolved markedly over the last 50 years, such that there are now an established clinical definition, validated methods of fracture risk assessment and a range of effective pharmacological agents. Currently, bone-forming (anabolic) agents, in many countries, are used in those patients who have continued to lose bone mineral density (BMD), patients with multiple subsequent fractures or those who have fractured despite treatment with antiresorptive agents. However, head-to-head data suggest that anabolic agents have greater rapidity and efficacy for fracture risk reduction than do antiresorptive therapies. The European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) convened an expert working group to discuss the tools available to identify patients at high risk of fracture, review the evidence for the use of anabolic agents as the initial intervention in patients at highest risk of fracture and consider the sequence of therapy following their use. This position paper sets out the findings of the group and the consequent recommendations. The key conclusion is that the current evidence base supports an "anabolic first" approach in patients found to be at very high risk of fracture, followed by maintenance therapy using an antiresorptive agent, and with the subsequent need for antiosteoporosis therapy addressed over a lifetime horizon.

Incidence and predictors of fragility fracture in postmenopausal rheumatoid arthritis patients receiving oral bisphosphonates: a longitudinal observational study

Background

Although many studies have reported the predictors of fractures in patients with rheumatoid arthritis (RA) who are not receiving anti-osteoporotic treatments or who are receiving unspecified treatments, studies focusing on the predictors of fracture in patients with RA who are currently being treated with oral bisphosphonates (BP) are quite scarce. This study aims to investigate the incidence and predictors of fragility fracture in postmenopausal patients with RA receiving oral BP.

Methods

This retrospective longitudinal observational study comprised 98 postmenopausal RA patients receiving oral BP for a minimum of 6 months between April 2015 and December 2020. The cumulative incidence of fragility fractures including vertebral and nonvertebral fractures was investigated using the Kaplan–Meier method. Cox proportional hazards analysis was used to analyze baseline predictors of future fragility fractures. To determine a cutoff value of continuous predictors, the receiver-operating characteristic curve was applied.

Results

Twenty patients developed fractures during the study period, with a cumulative incidence of 6.1% at 12 months, 10.5% at a median follow-up of 28 months, and 14.4% at 36 months. Multivariable Cox hazards analysis showed a history of prior vertebral fracture (hazard ratio [HR] 6.26, 95% confidence interval [CI] 1.99‒19.68, P = 0.001) and dose of methotrexate (HR 0.87, 95% CI 0.76‒0.99, P = 0.041) to be independent predictors. The cutoff value for methotrexate dose was 4 mg/week.

Conclusions

We found a cumulative incidence of any fractures of 10.5% at 28 months in patients with RA currently being treated with oral BP. A history of prior vertebral fractures and methotrexate dose were positive and negative predictors for fractures, respectively. Practitioners should consider selecting another anti-osteoporotic drug in patients with RA who remain at risk despite receiving oral BP.

Bone-loading exercises versus risedronate for the prevention of osteoporosis in postmenopausal women with low bone mass: a randomized controlled trial

PURPOSE

This randomized controlled trial compared changes in bone mineral density (BMD) and bone turnover in postmenopausal women with low bone mass randomized to 12 months of either risedronate, exercise, or a control group.

METHODS

Two hundred seventy-six women with low bone mass, within 6 years of menopause, were included in analysis. Treatment groups were 12 months of (a) calcium and vitamin D supplements (CaD) (control), (b) risedronate + CaD (risedronate), or (c) bone-loading exercises + CaD (exercise). BMD and serum markers for bone formation (Alkphase B) and resorption (Serum Ntx) were analyzed at baseline, 6, and 12 months.

RESULTS

Using hierarchical linear modeling, a group by time interaction was found for BMD at the spine, indicating a greater improvement in the risedronate group compared to exercise (p ≤ .010) or control groups (p ≤ .001). At 12 months, for women prescribed risedronate, changes in BMD at the spine, hip, and femoral neck from baseline were + 1.9%, + 0.9%, and + .09%; in exercise group women, + 0.2%, + 0.5%, and - 0.4%; and in control group women, - 0.7%, + 0.5%, and - 0.5%. There were also significant differences in reductions in Alkphase B (RvsE, p < .001, RvsC, p < .001) and Serum Ntx (RvsE, p = .004, RvsC, p = .007) in risedronate women compared to exercise and control groups. For risedronate, 12-month changes in Alkphase B and Serum Ntx were - 20.3% and - 19.0%; for exercise, - 6.7% and - 7.0%; and for control, - 6.3% and - 9.0%.

CONCLUSION

Postmenopausal women with low bone mass should obtain adequate calcium and vitamin D and participate in bone-loading exercises. Additional use of BPs will increase BMD, especially at the spine.

Serum levels of C-terminal telopeptide (CTX) are associated with muscle function in community-dwelling older adults

BACKGROUND

Markers of bone metabolism have been associated with muscle mass and function. Whether serum cross-linked C-terminal telopeptides of type I collagen (CTX) is also associated with these measures in older adults remains unknown.

METHODS

In community-dwelling older adults at high risk of falls and fractures, serum CTX (biochemical immunoassays) was used as the exposure, while appendicular lean mass (dual-energy x-ray absorptiometry) and muscle function (grip strength [hydraulic dynamometer], short physical performance battery [SPPB], gait speed, sit to stand, balance, Timed Up and Go [TUG]) were used as outcomes. Potential covariates including demographic, lifestyle and clinical factors were considered in statistical models. Areas under the ROC curves were calculated for significant outcomes.

RESULTS

299 older adults (median age: 79 years, IQR: 73, 84; 75.6% women) were included. In multivariable models, CTX was negatively associated with SPPB (β = 0.95, 95% CI: 0.92, 0.98) and balance (β = 0.92, 0.86, 0.99) scores, and positively associated with sit to stand (β = 1.02, 95% CI: 1.00, 1.05) and TUG (β = 1.03, 95% CI: 1.00, 1.05). Trend line for gait speed (β = 0.99, 95% CI: 0.98, 1.01) was in the hypothesized direction but did not reach significance. AUC curves showed low diagnostic power (<0.7) of CTX in identifying poor muscle function (SPPB: 0.63; sit to stand: 0.64; TUG: 0.61).

CONCLUSION

In older adults, higher CTX levels were associated with poorer lower-limb muscle function (but showed poor diagnostic power for these measures). These clinical data build on the biomedical link between bone and muscle.

[18F] Sodium Fluoride PET Kinetic Parameters in Bone Imaging

This report describes the significance of the kinetic parameters (k-values) obtained from the analysis of dynamic positron emission tomography (PET) scans using the Hawkins model describing the pharmacokinetics of sodium fluoride ([¹⁸F]NaF) to understand bone physiology. Dynamic [¹⁸F]NaF PET scans may be useful as an imaging biomarker in early phase clinical trials of novel drugs in development by permitting early detection of treatment-response signals that may help avoid late-stage attrition.

Advances in bone turnover markers

Bone fragility fractures remain an important worldwide health and economic problem due to increased morbidity and mortality. The current methods for predicting fractures are largely based on the measurement of bone mineral density and the utilization of mathematical risk calculators based on clinical risk factors for bone fragility. Despite these approaches, many bone fractures remain undiagnosed. Therefore, current research is focused on the identification of new factors such as bone turnover markers (BTM) for risk calculation. BTM are a group of proteins and peptides released during bone remodeling that can be found in serum or urine. They derive from bone resorptive and formative processes mediated by osteoclasts and osteoblasts, respectively. Potential use of BTM in monitoring these phenomenon and therefore bone fracture risk is limited by physiologic and pathophysiologic factors that influence BTM. These limitations in predicting fractures explain why their inclusion in clinical guidelines remains limited despite the large number of studies examining BTM.

Considerations for understanding protein measurements: Identification of formation, degradation and more pathological relevant epitopes

OBJECTIVES

There is a need for precision medicine and an unspoken promise of an optimal approach for identification of the right patients for value-based medicine based on big data. However, there may be a misconception that measurement of proteins is more valuable than measurement of fewer selected biomarkers. In population-based research, variation may be somewhat eliminated by quantity. However, this fascination of numbers may limit the attention to and understanding of the single. This review highlights that protein measurements (with collagens as examples) may mean different things depending on the targeted epitope - formation or degradation of tissues, and even signaling potential of proteins.

DESIGN AND METHODS

PubMed was searched for collagen, neo-epitope, biomarkers.

RESULTS

Ample examples of assays with specific epitopes, either pathological such as HbA1c, or domain specific such as pro-peptides, which total protein arrays would not have identified were evident.

CONCLUSIONS

We suggest that big data may be considered as the funnel of data points, in which most important parameters will be selected. If the technical precision is low or the biological accuracy is limited, and we include suboptimal quality of biomarkers, disguised as big data, we may not be able to fulfill the promise of helping patients searching for the optimal treatment. Alternatively, if the technical precision of the total protein quantification is high, but we miss the functional domains with the most considerable biological meaning, we miss the most important and valuable information of a given protein. This review highlights that measurements of the same protein in different ways may provide completely different meanings. We need to understand the pathological importance of each epitope quantified to maximize protein measurements.

Biomarkers as therapy monitoring for postmenopausal osteoporosis: a systematic review

Background

Biochemical markers of bone turnover (BTMs), such as bone alkaline phosphatase (bALP), procollagen type I N propeptide (PINP), serum cross-linked C-telopeptides of type I collagen (bCTx), and urinary cross-linked N-telopeptides of type I collagen (NTx), are commonly used for therapy monitoring purposes for osteoporotic patients. The present study evaluated the potential role of BTMs as therapy monitoring.

Methods

All randomized clinical trials (RCTs) comparing two or more pharmacological treatments for postmenopausal osteoporosis were accessed. Only studies that reported the value of bALP, PINP, bCTx, and NTx at last follow-up were included. A multivariate analysis was performed to assess associations between these biomarkers and clinical outcomes and rate of adverse events in patients with postmenopausal osteoporosis. A multiple linear model regression analysis through the Pearson product-moment correlation coefficient was used.

Results

A total of 16 RCTs (14,446 patients) were included. The median age was 67 years, and the median BMI 25.4 kg/m². The median vertebral BMD was 0.82, hip BMD 0.79, and femur BMD 0.64 g/cm². The ANOVA test found optimal within-group variance concerning mean age, body mass index, and BMD. Greater bALP was associated with lower femoral BMD (P = 0.01). Greater NTx was associated with a greater number of non-vertebral fractures (P = 0.02). Greater NTx was associated with greater rate of therapy discontinuation (P = 0.04). No other statistically significant associations were detected.

Conclusion

Our analysis supports the adoption of BTMs in therapy monitoring of osteoporotic patients.

Level of evidence

Level I, systematic review of RCTs.

Effect of cytotoxic chemotherapy on bone health among breast cancer patients. Does it require intervention?

BACKGROUND

Breast cancer (BC) is one of the most common malignancies worldwide. Although the burden and mechanisms of endocrine therapy-related bone loss are known, the evidence is scanty regarding the impact of cytotoxic chemotherapy on bone health. We have attempted to summarize the effect of cytotoxic chemotherapy on bone health in BC patients.

METHODS

A comprehensive literature search was performed via MEDLINE and Cochrane library databases to evaluate the effect of chemotherapy on bone health among women with BC. We included articles related to skeletal-related events, bone mineral density, bone turnover markers, osteoporosis-specific quality of life, bisphosphonate, and other bone-directed therapy. We excluded articles that included patients with metastatic breast cancer and patients receiving hormonal therapy.

DISCUSSION

Bone microenvironment in cancer is directly or indirectly influenced by clinical, hormonal, nutritional, and treatment factors. Calcitonin, parathyroid hormone, calcitriol, and estrogen are the major hormonal regulators. Bone turnover markers, namely bone formation and resorption markers, have been used to predict bone loss, fracture risk, and monitoring treatment response. Chemotherapeutic drugs such as anthracyclines and taxanes synergistically affect BMD and quality of life. Calcium, vitamin D, bisphosphonates, and denosumab are supplemented to prevent excess bone resorption. Bone-targeted anti-resorptive agents have been studied as potential anticancer agents in the adjuvant treatment of breast cancer.

CONCLUSION

This review summarizes the negative effect of chemotherapy on bone health of BC patients and the importance of preventing or treating bone loss.

Real-world bone turnover marker use: impact on treatment decisions and fracture

The use of bone turnover marker (BTM) testing for patients with osteoporosis in the USA has not been well characterized. This retrospective US-based real-world data study found BTM testing has some association with treatment decision-making and lower fracture risk in patients with presumed osteoporosis, supporting its use in clinical practice.

INTRODUCTION

The purpose of this study was to characterize bone turnover marker (BTM) testing patterns and estimate their clinical utility in treatment decision-making and fragility fracture risk in patients with osteoporosis using a retrospective claims database.

METHODS

Data from patients aged ≥ 50 years with newly diagnosed osteoporosis enrolled in the Truven MarketScan^® Commercial Claims and Encounters and Medicare Supplemental and Co-ordination of Benefits databases from January 2008 to June 2018 were included. Osteoporosis was ascertained by explicit claims, fragility fracture events associated with osteoporosis, or prescribed anti-resorptive or anabolic therapy. BTM-tested patients were 1:1 propensity score matched to those untested following diagnosis. Generalized estimating equation models were performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for testing versus no testing on both treatment decision-making and fragility fracture.

RESULTS

Of the 457,829 patients with osteoporosis, 6075 were identified with ≥ 1 BTM test following diagnosis; of these patients, 1345 had a unique treatment decision made ≤ 30 days from BTM testing. The percentage of patients receiving BTM tests increased significantly each year (average annual % change: + 8.1%; 95% CI: 5.6-9.0; p = 0.01). Patients tested were significantly more likely to have a treatment decision (OR: 1.14; 95% CI: 1.13-1.15), and testing was associated with lower odds of fracture versus those untested (OR: 0.87; 95% CI: 0.85-0.88).

CONCLUSION

In this large, heterogeneous population of patients with presumed osteoporosis, BTM testing was associated with treatment decision-making, likely leading to fragility fracture reduction following use.

European Consensus Statement on the diagnosis and management of osteoporosis in chronic kidney disease stages G4-G5D

Controlling the excessive fracture burden in patients with chronic kidney disease (CKD) Stages G4-G5D remains an impressive challenge. The reasons are 2-fold. First, the pathophysiology of bone fragility in patients with CKD G4-G5D is complex and multifaceted, comprising a mixture of age-related (primary male/postmenopausal), drug-induced and CKD-related bone abnormalities. Second, our current armamentarium of osteoporosis medications has not been developed for, or adequately studied in patients with CKD G4-G5D, partly related to difficulties in diagnosing osteoporosis in this specific setting and fear of complications. Doubts about the optimal diagnostic and therapeutic approach fuel inertia in daily clinical practice. The scope of the present consensus paper is to review and update the assessment and diagnosis of osteoporosis in patients with CKD G4-G5D and to discuss the therapeutic interventions available and the manner in which these can be used to develop management strategies for the prevention of fragility fracture. As such, it aims to stimulate a cohesive approach to the management of osteoporosis in patients with CKD G4-G5D to replace current variations in care and treatment nihilism.

Biomarkers for prediction of skeletal disease progression in mucopolysaccharidosis type I

BACKGROUND

Orthopedic disease progresses in mucopolysaccharidosis type I (MPS I), even with approved therapies and remains a major factor in persistent suffering and disability. Novel therapies and accurate predictors of response are needed. The primary objective of this study was to identify surrogate biomarkers of future change in orthopedic disease.

METHODS

As part of a 9-year observational study of MPS I, range-of-motion (ROM), height, pelvic radiographs were measured annually. Biomarkers in year 1 were compared to healthy controls. Linear regression tested for associations of change in biomarkers over the first year with change in long-term outcomes.

RESULTS

MPS I participants (N = 19) were age 5 to 16 years and on average 6.9 ± 2.9 years post treatment initiation. Healthy controls (N = 51) were age 9 to 17 years. Plasma IL-1β, TNF-α, osteocalcin, pyridinolines, and deoxypyridinolines were higher in MPS than controls. Within MPS, progression of hip dysplasia was present in 46% to 77%. A 1 pg/mL increase in IL-6 was associated with -22°/year change in ROM (-28 to -15; P < .001), a 20 nmol/mmol creatinine/year increase in urine PYD was associated with a -0.024 Z-score/year change in height Z-score (-0.043 to -0.005; P = .016), and a 20 nmol/mmol creatinine/year increase in urine PYD was associated with a -2.0%/year change in hip dysplasia measured by Reimers migration index (-3.8 to -0.1; P = .037).

CONCLUSIONS

Inflammatory cytokines are high in MPS I. IL-6 and PYD were associated with progression in joint contracture, short stature, and hip dysplasia over time. Once validated, these biomarkers may prove useful for predicting response to treatment of skeletal disease in MPS I.

A tree shrew model for steroid-associated osteonecrosis

Osteonecrosis is a common human disease in orthopedics. It is difficult to treat, and half of patients may need artificial joint replacement, resulting in a considerable economic burden and a reduction in quality of life. Hormones are one of the major causes of osteonecrosis and high doses of corticosteroids are considered the most dangerous factor. Because of the complexity of treatment, we still need a better animal model that can be widely used in drug development and testing. Tree shrews are more closely related to primates than rodents. As such, we constructed a successful tree shrew model to establish and evaluate steroid-associated osteonecrosis (SAON). We found that low-dose lipopolysaccharide (LPS) combined with high-dose methylprednisolone (MPS) over 12 weeks could be used to establish a tree shrew model with femoral head necrosis. Serum biochemical and histological analyses showed that an ideal model was obtained. Thus, this work provides a useful animal model for the study of SAON and for the optimization of treatment methods.

Survival, fusion, and hardware failure after surgery for spinal metastatic disease

OBJECTIVE

Decompression with instrumented fusion is commonly employed for spinal metastatic disease. Arthrodesis is typically sought despite limited knowledge of fusion outcomes, high procedural morbidity, and poor prognosis. This study aimed to describe survival, fusion, and hardware failure after decompression and fusion for spinal metastatic disease.

METHODS

The authors retrospectively examined a prospectively collected, single-institution database of adult patients undergoing decompression and instrumented fusion for spinal metastases. Patients were followed clinically until death or loss to follow-up. Fusion was assessed using CT when performed for oncological surveillance at 6-month intervals through 24 months postoperatively. Estimated cumulative incidences for fusion and hardware failure accounted for the competing risk of death. Potential risk factors were analyzed with univariate Fine and Gray proportional subdistribution hazard models.

RESULTS

One hundred sixty-four patients were identified. The mean age ± SD was 62.2 ± 10.8 years, 61.6% of patients were male, 98.8% received allograft and/or autograft, and 89.6% received postoperative radiotherapy. The Kaplan-Meier estimate of median survival was 11.0 months (IQR 3.5-37.8 months). The estimated cumulative incidences of any fusion and of complete fusion were 28.8% (95% CI 21.3%-36.7%) and 8.2% (95% CI 4.1%-13.9%). Of patients surviving 6 and 12 months, complete fusion was observed in 12.5% and 16.1%, respectively. The estimated cumulative incidence of hardware failure was 4.2% (95% CI 1.5-9.3%). Increasing age predicted hardware failure (HR 1.2, p = 0.003).

CONCLUSIONS

Low rates of complete fusion and hardware failure were observed due to the high competing risk of death. Further prospective, case-control studies incorporating nonfusion instrumentation techniques may be warranted.

Bone Mineral Density and Turnover After Sleeve Gastrectomy and Gastric Bypass: A Randomized Controlled Trial (Oseberg)

CONTEXT

Bariatric surgery, particularly Roux-en-Y gastric bypass (RYGB), is associated with an increased risk of osteoporotic fractures. It is unknown whether RYGB or sleeve gastrectomy (SG) have different effects on bone health.

OBJECTIVE

To compare changes in bone mineral density and markers of bone turnover 1 year after SG and RYGB.

DESIGN, SETTING, PATIENTS, AND INTERVENTIONS

Randomized, triple-blind, single-center trial at a tertiary care center in Norway. The primary outcome was diabetes remission. Patients with severe obesity and type 2 diabetes were randomized and allocated (1:1) to SG or RYGB.

MAIN OUTCOME MEASURES

Changes in areal bone mineral density (aBMD) and bone turnover markers.

RESULTS

Femoral neck, total hip, and lumbar spine aBMD, but not total body aBMD, decreased significantly more after RYGB (n = 44) than after SG (n = 48) (mean [95% confidence interval] between group differences -2.8% [-4.7 to -0.8], -3.0% [-5.0 to -0.9], -4.2% [-6.4 to -2.1], and -0.5% [-1.6 to 0.6], respectively). The increase in procollagen type 1 N-terminal propeptide (P1NP) and C-telopeptide of type I collagen (CTX-1) were approximately 100% higher after RYGB than after SG (between group difference at 1 year, both P < 0.001). The changes in femoral neck, total hip, and lumbar spine aBMDs and the changes in P1NP and CTX-1 were independently associated with the surgical procedure (all P < 0.05) and not weight change.

CONCLUSIONS

Roux-en-Y gastric bypass was associated with a greater reduction in aBMD and a greater increase in bone turnover markers compared with SG. This finding could suggest greater skeletal fragility after RYGB.

Association of Insulin Resistance and β-cell Function With Bone Turnover Biomarkers in Dysglycemia Patients

BACKGROUND

The interrelation between glucose and bone metabolism is complex and has not been fully revealed. This study aimed to investigate the association between insulin resistance, β-cell function and bone turnover biomarker levels among participants with abnormal glycometabolism.

METHODS

A total of 5277 subjects were involved through a cross-sectional study (METAL study, http://www.chictr.org.cn, ChiCTR1800017573) in Shanghai, China. Homeostasis model assessment of insulin resistance (HOMA-IR) and β-cell dysfunction (HOMA-%β) were applied to elucidate the nexus between β-C-terminal telopeptide (β-CTX), intact N-terminal propeptide of type I collagen (P1NP) and osteocalcin (OC). β-CTX, OC and P1NP were detected by chemiluminescence.

RESULTS

HOMA-IR was negatively associated with β-CTX, P1NP and OC (regression coefficient (β) -0.044 (-0.053, -0.035), Q4vsQ1; β -7.340 (-9.130, -5.550), Q4vsQ1 and β -2.885 (-3.357, -2.412), Q4vsQ1, respectively, all P for trend <0.001). HOMA-%β was positively associated with β-CTX, P1NP and OC (β 0.022 (0.014, 0.031), Q4vsQ1; β 6.951 (5.300, 8.602), Q4vsQ1 and β 1.361 (0.921, 1.800), Q4vsQ1, respectively, all P for trend <0.001).

CONCLUSIONS

Our results support that lower bone turnover biomarker (β-CTX, P1NP and OC) levels were associated with a combination of higher prevalence of insulin resistance and worse β-cell function among dysglycemia patients. It is feasible to detect bone turnover in diabetes or hyperglycemia patients to predict the risk of osteoporosis and fracture, relieve patients' pain and reduce the expenses of long-term cure.

Effects of paprika carotenoid supplementation on bone turnover in postmenopausal women: a randomized, double-blind, placebo-controlled, parallel-group comparison study

Background

Paprika (Capsicum annuum L.) is a good source of carotenoids, including capsanthin, β-carotene, β-cryptoxanthin, and zeaxanthin. Several epidemiological studies have shown a beneficial association of intake of these carotenoids or their blood concentration with bone mineral density (BMD) and fracture risk. However, little information is available regarding the effect of intake of these carotenoids on bone metabolism in postmenopausal women.

Objective

The objective of the present study was to investigate the effects of paprika carotenoid extract (PCE) on bone turnover in healthy, postmenopausal women.

Design

We conducted a randomized, double-blind, placebo-controlled, parallel-group comparison study. One hundred participants were randomly assigned to PCE or placebo groups. Each group was given a 20 mg PCE (equivalent to 1.4 mg of carotenoids) a day or a placebo for 24 weeks. We measured bone resorption markers (tartrate-resistant acid phosphatase 5b [TRACP-5b] and serum type I collagen cross-linked N-telopeptide [sNTX]) at 12 and 24 weeks and bone formation markers (bone alkaline phosphatase and osteocalcin) at 24 weeks.

Results

The percentage decrease of TRACP-5b at 24 weeks was significantly higher for PCE than the placebo. There were no significant differences in sNTX or bone formation markers, although PCE decreased each marker compared with the placebo.

Conclusion

Our findings suggest that PCE supplementation suppresses bone resorption and contributes to maintaining bone quality in postmenopausal women.

Bone turnover markers to assess jawbone quality prior to dental implant treatment: a case-control study

Background

Bone quality is as important as bone mineral density in terms of bone strength. Bone turnover markers (BTMs) are clinical indicators of bone quality. In implant dentistry, bone quality is considered equivalent to bone density on radiographic assessments. The purpose of this study was to determine whether the BTM values are reflected in jawbone condition by evaluating the relationship at baseline and during follow-up in patients with prosthodontic implants.

Computed tomography (CT) scans were obtained and BTM (osteocalcin, bone-specific alkaline phosphatase, pyridinoline cross-linked carboxyterminal telopeptide of type I collagen, and crosslinked N-telopeptide of type I collagen) levels in blood samples were measured in partially edentulous eighteen patients before implant surgery. During the follow-up observation after implant surgery, marginal bone loss (MBL) was measured on dental radiography. We investigated the relationship between the presence of BTM abnormalities and radiographic bone density.

Results

More women than men had abnormal BTM values. Bone turnover was accelerated in the group of women with abnormal BTM values. The density of cancellous bone at the implant placement site was significantly lower in the patients with abnormally high BTM values than in their counterparts with BTM values in the normal range.

Conclusions

Female patients who undergo implant treatments may have reduced bone quality; evaluations of bone strength will require assessments of both BTMs and the density of cancellous bone.

Enrichment of Collagen Fragments Using Dimeric Collagen Hybridizing Peptide for Urinary Collagenomics

Collagen remodeling in normal and pathologic conditions releases numerous collagen fragments into biological fluids. Although a few collagen fragments have been tested as biomarkers for disease indication, most occur at trace levels, making them nearly impossible to detect even with modern analytical tools. Here we report a new way to enrich collagen fragments that allows complete peptidomic analysis of collagen fragments in urine. Enrichment is made possible by dimeric collagen hybridizing peptides (CHPs) that bind collagen fragments originating from the triple helical regions of all collagen types with minimal sequence bias. LC-MS/MS analysis of enriched mouse urine revealed an average of 383 collagenous peptide fragments per sample (compared to 34 for unenriched sample), which could be mapped to all types of mouse collagens in the SwissProt database including FACITs and MACITs. Hierarchical clustering of a selected panel of the detected fragments separated osteopenic mice from healthy mice. The results demonstrate dimeric CHP's ability to enrich collagen fragments from biological fluid and its potential to aid peptidomics-based disease detection and biomarker discovery.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS/AMERICAN COLLEGE OF ENDOCRINOLOGY CLINICAL PRACTICE GUIDELINES FOR THE DIAGNOSIS AND TREATMENT OF POSTMENOPAUSAL OSTEOPOROSIS-2020 UPDATE

Objective: The development of these guidelines is sponsored by the American Association of Clinical Endocrinologists (AACE) Board of Directors and American College of Endocrinology (ACE) Board of Trustees and adheres with published AACE protocols for the standardized production of clinical practice guidelines (CPGs). Methods: Recommendations are based on diligent reviews of the clinical evidence with transparent incorporation of subjective factors, according to established AACE/ACE guidelines for guidelines protocols. Results: The Executive Summary of this 2020 updated guideline contains 52 recommendations: 21 Grade A (40%), 24 Grade B (46%), 7 Grade C (14%), and no Grade D (0%). These detailed, evidence-based recommendations allow for nuance-based clinical decision-making that addresses multiple aspects of real-world care of patients. The evidence base presented in the subsequent Appendix provides relevant supporting information for the Executive Summary recommendations. This update contains 368 citations: 123 (33.5%) evidence level (EL) 1 (highest), 132 (36%) EL 2 (intermediate), 20 (5.5%) EL 3 (weak), and 93 (25%) EL 4 (lowest). New or updated topics in this CPG include: clarification of the diagnosis of osteoporosis, stratification of the patient according to high-risk and very-high-risk features, a new dual-action therapy option, and transitions from therapeutic options. Conclusion: This guideline is a practical tool for endocrinologists, physicians in general, regulatory bodies, health-related organizations, and interested laypersons regarding the diagnosis, evaluation, and treatment of post-menopausal osteoporosis. Abbreviations: 25(OH)D = 25-hydroxyvitamin D; AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; AFF = atypical femoral fracture; ASBMR = American Society for Bone and Mineral Research; BEL = best evidence level; BMD = bone mineral density; BTM = bone turnover marker; CI = confidence interval; CPG = clinical practice guideline; CTX = C-terminal telopeptide type-I collagen; DXA = dual-energy X-ray absorptiometry; EL = evidence level; FDA = U.S. Food and Drug Administration; FRAX® = Fracture Risk Assessment Tool; GI = gastrointestinal; HORIZON = Health Outcomes and Reduced Incidence with Zoledronic acid ONce yearly Pivotal Fracture Trial (zoledronic acid and zoledronate are equivalent terms); ISCD = International Society for Clinical Densitometry; IU = international units; IV = intravenous; LSC = least significant change; NOF = National Osteoporosis Foundation; ONJ = osteonecrosis of the jaw; PINP = serum amino-terminal propeptide of type-I collagen; PTH = parathyroid hormone; R = recommendation; ROI = region of interest; RR = relative risk; SD = standard deviation; TBS = trabecular bone score; VFA = vertebral fracture assessment; WHO = World Health Organization.

The challenge of long-term adherence: The role of bone turnover markers in monitoring bisphosphonate treatment of osteoporosis

Oral Bisphosphonates (BPs) are the mainstay of osteoporotic treatment, however long-term adherence remains a challenge, primarily owing to the chronic character of the disease and the regimen complexity. Poor compliance has been shown to have a clear link to fracture risk. The role of bone turnover markers (BTMs) as a tool to ascertain adherence and response to therapy is supported by their rapid response to treatment; a decrease in values is witnessed within days or weeks of commencing treatment. A greater reduction of serum CTX and NTX is evidenced with alendronate and ibandronate compared to risedronate. A change in bone formation BTMs appears to be related to vertebral fracture risk reduction, whereas no significant relationship is evident for hip and non-vertebral fractures. The utility of BTMs as an adjunct for monitoring withdrawal of treatment with oral BP has also been suggested. Finally, studies evaluating BTMs as an intervention, failed to demonstrate any effect on adherence. This review explores the challenge of long-term adherence with bisphosphonates and provides an analytic framework with respect to the role of BTMs in monitoring bisphosphonate treatment, adherence and the offset of treatment effect.

Early changes in bone turnover predict longer-term changes in bone mineral density but not trabecular bone score in frail older women

Clinicians and patients want to know if therapy is working early in their course of treatment. We found that early changes in bone turnover markers at 6 months were associated with long-term changes in bone mineral density but not trabecular bone score at 12 and 24 months.

PURPOSE

We sought to examine the association between shorter-term changes in markers of bone turnover and longer-term changes in bone mineral density (BMD) and microstructure in a cohort of frail elderly women with multiple comorbid conditions including osteoporosis.

METHODS

We performed a secondary analysis of a 2-year zoledronic acid trial for osteoporosis in 155 women residents of long-term care communities (mean age 86.9 years). We examined the association of the 6-month change in serum C-terminal crosslinking telopeptide of type I collagen (CTX) and serum intact procollagen type I N propeptide (PINP) with the 12- and 24-month changes in BMD at the spine and hip and the trabecular bone score (TBS), an indirect measure of bone microstructure.

RESULTS

For every 0.2-ng/ml 6-month CTX decrease, the corresponding increase in spine BMD at 12 and 24 months was 0.2% (p = 0.7210) and 1.1% (p = 0.0396), respectively; total hip BMD 1.1% (p = 0.0279) and 0.9% (p = 0.0716); and femoral neck BMD 1.7% (p = 0.0079) and 0.9% (p = 0.1698). Similarly, for every 20-ng/ml 6-month PINP decrease, the corresponding increase in spine BMD at 12 and 24 months was 0.9% (p = 0.0286) and 1.4% (p = 0.0012), respectively; total hip BMD 1.4% (p = 0.0005) and 1.4% (p = 0.0006); and femoral neck BMD 2.3% (p < 0.0001) and 2.0% (p < 0.0001). Bone marker changes were not consistently associated with TBS changes.

CONCLUSION

Shorter-term 6-month changes in bone turnover markers are associated with the long-term changes in BMD over 1-2 years in the spine and hip but not with TBS.

Bone Turnover Markers After Standard and Distal Roux-en-Y Gastric Bypass: Results from a Randomized Controlled Trial

BACKGROUND

Roux-en-Y gastric bypass is associated with increased risk of bone fractures. Malabsorptive procedures may be associated with secondary hyperparathyroidism and detrimental effects on bone health. We aimed to compare the effects of standard and distal gastric bypass on bone turnover markers 2 years after surgery.

METHODS

Patients with body mass index (BMI) 50-60 kg/m² (n = 113) were randomized to standard or distal gastric bypass, 105 patients (95%) completed 2-year follow-up. Serum C-terminal telopeptide of type I collagen (CTX-1), procollagen type I N-propeptide (PINP), and bone-derived alkaline phosphatase (BALP) was measured at baseline and up to 2 years after surgery. ANCOVA and linear mixed models were used to compare groups.

RESULTS

The levels of bone turnover markers increased significantly in both groups, with no statistically significant difference between groups. Two years after standard and distal gastric bypass mean (SD) CTX-1 were 0.81 (0.32) and 0.83 (0.31) μg/L (p = 0.38), mean PINP was 77.6 (23.2) and 77.7 (29.3) μg/L (p = 0.42), and BALP 47.9 (21.9) vs. 50.7 (19.6) μg/L (p = 0.38), respectively. Multiple linear regression analyses showed that PINP and BALP correlated positively (p = 0.01 and p < 0.001) with PTH, but only BALP was significantly higher in patients with secondary hyperparathyroidism (p = 0.001). Type of surgery, vitamin D serum concentrations, and 2-year BMI were all independently associated with PTH levels.

CONCLUSION

A comparable increase in bone turnover markers 2 years after standard and distal gastric bypass was observed. There was a higher prevalence of secondary hyperparathyroidism after distal gastric bypass, but this did not impact bone turnover markers.

TRIAL REGISTRATION

Clinical Trials.gov number NCT00821197.

Association between metabolic profiles in urine and bone mineral density of pre- and postmenopausal Chinese women

OBJECTIVE

In the present study, we aimed to characterize the pathological development of menopausal osteoporosis, as well as to explore potential biomarkers and metabolic pathways involved in osteoporosis.

METHODS

Urine samples from 322 female participants categorized by menopause status and different bone conditions were collected and analyzed based on a gas chromatography-mass spectrometry (GC-MS) approach. Multivariate and univariate statistical analyses were carried out for urinary metabolomic profile characterization and comparison.

RESULTS

Seventeen metabolites in the low bone mineral density (BMD) groups were clearly differentiated from those in normal BMD groups. Among these 17 differentiating metabolites, taurine, β-alanine, and 5-hydroxycaproic acid were found to be potential biomarkers of osteoporosis. The taurine metabolic pathway and the β-alanine metabolic pathway were found to be related to menopause and bone loss.

CONCLUSIONS

Based on the GC-MS metabolomic platform, four typical pathological phases during the progression of postmenopausal osteoporosis were described. Several differentiating metabolites and metabolic pathways were found to be closely related to the pathology of postmenopausal osteoporosis. Our results provided a solid foundation for further studies on early diagnosis and pathomechanistic evaluation.

The Association between Fast Increase in Bone Turnover During the Menopause Transition and Subsequent Fracture

CONTEXT

Bone turnover increases rapidly during the menopause transition (MT) and plateaus above premenopausal levels in early postmenopause. It is uncertain whether higher bone turnover is associated with fracture in midlife women with near-normal bone mineral density (BMD).

OBJECTIVE

Examine whether faster increases in bone turnover during the MT (2 years before to 2 years after the final menstrual period [FMP]), and greater bone turnover during early postmenopause (≥2 years after the FMP) are risk factors for subsequent fracture, accounting for BMD.

DESIGN AND SETTING

The Study of Women's Health Across the Nation, a longitudinal cohort study of the MT.

PARTICIPANTS

A total of 484 women (initially pre- or early perimenopausal, who transitioned to postmenopause) with bone turnover (urine collagen type I N-telopeptide), BMD, and fracture data.

MAIN OUTCOME MEASURE

Incident fracture after the MT.

RESULTS

Adjusting for age, race/ethnicity, fracture before the MT, cigarette use, body mass index, and study site in Cox proportional hazards regression, each SD increment in the rate of increase in bone turnover during the MT was associated with 24% greater hazard of incident fracture in postmenopause (P = .008). Accounting for the same covariates, each SD increment in bone turnover during early postmenopause was associated with a 27% greater hazard of fracture (P = .01). Associations remained significant after controlling for MT rate of change and early postmenopausal level of BMD.

CONCLUSION

Faster increases in bone turnover during the MT and greater bone turnover in early postmenopause forecast future fractures.

The cartilage degradation marker, urinary CTX-II, is associated with the risk of incident total joint replacement in postmenopausal women. A 18 year evaluation of the OFELY prospective cohort

OBJECTIVE

Identifying objective risk-indicators for total joint replacement (TJR) is useful to enrich population at high risk in OA clinical trials. We investigate the association of urinary CTX-II, a biochemical marker of cartilage breakdown, with the risk of TJR.

METHOD

478 postmenopausal women (mean age 65.5 ± 7.5 yr) from the OFELY cohort were studied. CTX-II, serum CTX-I (bone resorption) and PINP (bone formation), were measured at baseline. Association between CTX-II and incidence of TJR was assessed by Cox Hazard Regression.

RESULTS

During a median (95%CI) 17.8 (15.0-18.1) years follow-up, 38 women sustained a TJR, including hip (n = 29) or knee (n = 9) replacement. CTX-II -but not CTX-I or PINP- was higher in patients with TJR (+34%, P = 0.001 vs women with no TJR). Increased baseline CTX-II levels were associated with a higher risk of TJR with a Hazard Ratio (HR) (95 CI) of 1.45 (1.13-1.85) per 1 SD increase after adjustment for age, BMI and total hip BMD. CTX-II remained significantly associated with the risk of TJR after further adjustment for total WOMAC, prevalent knee OA (KL ≥ 2) and self-reported hip OA [HR (95 CI): 1.31 (1.01-1.71), P = 0,04]. When women were categorized as low and high CTX-II (lower and above the 95 percentile of healthy premenopausal women, respectively), subjects with high levels had an age-BMI-hip BMD adjusted HR (95 CI) of 3.00 (1.54-5.85) compared to women with low levels which remained significant after further adjustment for WOMAC, knee and/or hip OA [HR (95 CI): 2.45 (1.25-4.89), P = 0.01].

CONCLUSION

CTX-II is an independent risk indicator of TJR in postmenopausal women suggesting that it may be useful to identify subjects at high risk of TJR.

Potential Biomarkers to Improve the Prediction of Osteoporotic Fractures

Osteoporotic fracture (OF) is associated with high disability and morbidity rates. The burden of OF may be reduced by early identification of subjects who are vulnerable to fracture. Although the current fracture risk assessment model includes clinical risk factors (CRFs) and bone mineral density (BMD), its overall ability to identify individuals at high risk for fracture remains suboptimal. Efforts have therefore been made to identify potential biomarkers that can predict the risk of OF, independent of or combined with CRFs and BMD. This review highlights the emerging biomarkers of bone metabolism, including sphongosine-1-phosphate, leucine-rich repeat-containing 17, macrophage migration inhibitory factor, sclerostin, receptor activator of nuclear factor-κB ligand, and periostin, and the importance of biomarker risk score, generated by combining these markers, in enhancing the accuracy of fracture prediction.

Osteoporosis and the Potential of Cell-Based Therapeutic Strategies

Osteoporosis, the most common chronic metabolic bone disease, is characterized by low bone mass and increased bone fragility. Nowadays more than 200 million individuals are suffering from osteoporosis and still the number of affected people is dramatically increasing due to an aging population and longer life, representing a major public health problem. Current osteoporosis treatments are mainly designed to decrease bone resorption, presenting serious adverse effects that limit their safety for long-term use. Numerous studies with mesenchymal stem cells (MSCs) have helped to increase the knowledge regarding the mechanisms that underlie the progression of osteoporosis. Emerging clinical and molecular evidence suggests that inflammation exerts a significant influence on bone turnover, thereby on osteoporosis. In this regard, MSCs have proven to possess broad immunoregulatory capabilities, modulating both adaptive and innate immunity. Here, we will discuss the role that MSCs play in the etiopathology of osteoporosis and their potential use for the treatment of this disease.