Dual-Energy X-Ray Absorptiometry Technical Issues: The 2007 ISCD Official Positions

A novel T2-weighted series-based modified vertebral bone quality score for evaluating bone mineral density

OBJECTIVE

To evaluate the modified vertebral bone quality (VBQ) method on the magnetic resonance imaging (MRI) T1-weighted (T1w), T2-weighted (T2w), and fat suppression (FS) series in evaluating bone mineral density (BMD) for patients with degenerative lumbar disease.

METHODS

We reviewed preoperative data of postmenopausal female patients aged ≥ 50 years hospitalized to undergo lumbar surgery for degenerative lumbar disease with available MRI and dual-energy X-ray absorptiometry (DEXA). Patients were categorized into three groups according to T-score. The VBQCSF score was calculated as the L1-L4 median signal intensity (SI) divided by the L3 CSF SI. One-way analysis of variance was applied to assess the discrepancy between groups. The diagnostic performance of VBQ scores for distinguishing low BMD was analyzed using receiver operating characteristic (ROC) analysis.

RESULTS

The study included 253 patients. T2 VBQCSF was significantly different between groups (p < 0.001). The interclass correlation coefficient for inter and intra-rater reliability was 0.767 (95%CI 0.650-0.849) and 0.893 (95%CI 0.834-0.932), respectively. The T2 VBQCSF showed moderate correlations with DEXA BMD (r =  - 0.442, p < 0.001). The area under the ROC curve indicated a predictive accuracy of 76%. A sensitivity of 59.0% with a specificity of 87.5% was achieved for distinguishing low BMD by setting the T2 VBQCSF cutoff at 0.607.

CONCLUSION

Compared to the traditional VBQ score, T2 VBQCSF is a more promising tool for distinguishing poor bone quality in patients with degenerative lumbar disease. A T2 VBQCSF score > 0.607 can identify patients who require additional diagnostic evaluation.

Musculoskeletal and body composition response to high-dose testosterone with finasteride after chronic incomplete spinal cord injury-a randomized, double-blind, and placebo-controlled pilot study

Background

High-dose testosterone replacement therapy (TRT), paired with finasteride (type II 5α-reductase inhibitor), improves body composition, muscle strength, and bone mineral density (BMD) in older men, without inducing prostate enlargement-a side effect associated with TRT. Men with spinal cord injury (SCI) exhibit neuromuscular impairment, muscle atrophy, bone loss, and increased central adiposity, along with low testosterone. However, sparse evidence supports TRT efficacy after SCI.

Methods

This parallel-group, double-blind, placebo-controlled, and randomized clinical trial (RCT) is a pilot study that enrolled men (N = 12) with low to low-normal testosterone and gait impairments after chronic motor-incomplete SCI. Participants received high-dose intramuscular TRT (testosterone-enanthate, 125 mg/week) with finasteride (5 mg/day) vs. vehicle+placebo for 12 months. Change relative to baseline was determined for body composition, musculoskeletal outcomes, and prostate size, with effect sizes calculated between groups using Hedges' g. Adverse events and feasibility were assessed.

Results

TRT + finasteride consistently increased testosterone (g = 1.16-3.08) and estradiol (g = 0.43-3.48), while concomitantly reducing dihydrotestosterone (g = 0.31-2.27). Very large effect sizes at both 6 and 12 months suggest TRT + finasteride increased whole-body fat-free (lean) mass (+3-4% vs. baseline, g = 2.12-2.14) and knee extensor (KE) whole-muscle cross-sectional area (+8-11% vs. baseline, g = 2.06-2.53) more than vehicle+placebo. Moderate-to-large effect sizes suggest TRT + finasteride increased KE maximal voluntary isometric torque (+15-40% vs. baseline, g = 0.47-1.01) and femoral neck and distal femur BMD from 6 months onward (g = 0.51-1.13), compared with vehicle+placebo, and reduced fat mass 9-14% within the whole-body, trunk, and android (visceral) regions at 12 months (g = 0.77-1.27). TRT + finasteride also produced small effect sizes favoring lesser prostate growth than vehicle+placebo (g = 0.31-0.43). The participant retention, drug compliance, and incidence and severity of adverse events were similar among the groups.

Conclusion

These data provide proof-of-concept and rationale for larger RCTs aimed at discerning the impact of TRT + finasteride on body composition, musculoskeletal health, and physical function in men with SCI, along with effect sizes and variance of responses to assist in planning subsequent trials.

Clinical trial registration

ClinicalTrials.gov, identifier NCT02248701.

Bone turnover markers in the preoperative assessment of bone quality - A prospective investigation of bone microstructure and advanced glycation endproducts in lumbar fusion patients

INTRODUCTION

Effective tools to evaluate bone quality preoperatively are scarce and the standard method to determine bone quality requires an invasive biopsy. A non-invasive, and preoperatively available method for bone quality assessment would be of clinical value. The purpose of this study is to investigate the associations of bone formation marker, serum bone alkaline phosphatase (BAP), and bone resorption marker, urine collagen cross-linked N-telopeptide (uNTX) to volumetric bone mineral density (vBMD), fluorescent advanced glycation endproducts (fAGEs) and bone microstructure.

MATERIALS AND METHODS

A cross-secional analysis using prospective data of patients undergoing lumbar spinal fusion was performed. BAP and uNTX were preoperatively collected. Quantitative computed tomography (QCT) was performed at the lumbar spine (vBMD ≤ 120 mg/cm3 osteopenic/osteoporotic). Bone biopsies from the posterior superior iliac spine were obtained and evaluated with multiphoton fluorescence microscopy for fAGEs and microcomputed tomography (µCT) for bone microarchitecture. Correlations between BAP/uNTX to vBMD, fAGEs and µCT parameters were assessed with Spearman's ρ. Receiver operating characteristic (ROC) analysis evaluated BAP and uNTX as predictors for osteopenia/osteoporosis. Multivariable linear regression models adjusting for age, sex, BMI, race and diabetes mellitus determined associations between BAP/uNTX and fAGEs.

RESULTS

127 prospectively enrolled patients (50.4% female, 62.5 years, BMI 28.7 kg/m2) were analyzed. uNTX (ρ=-0.331,p < 0.005) and BAP (ρ=-0.245,p < 0.025) decreased with cortical fAGEs, and uNTX (ρ=-0.380,p < 0.001) decreased with trabecular fAGEs. BAP and uNTX revealed no significant correlation with vBMD. ROC analysis for BAP and uNTX discriminated osteopenia/osteoporosis with AUC of 0.477 and 0.561, respectively. In the multivariable analysis, uNTX decreased with increasing trabecular fAGEs after adjusting for covariates (β = 0.923;p = 0.031).

CONCLUSION

This study demonstrated an inverse association of bone turnover markers and fAGEs. Both uNTX and BAP could not predict osteopenia/osteoporosis in the spine. uNTX reflects collagen characteristics and might have a complementary role to vBMD, as a non-invasive tool for bone quality assessment in spine surgery.

Correlations among MRI-based cervical and thoracic vertebral bone quality score, CT-based Hounsfield Unit score, and DEXA t-score in assessment of bone mineral density

BACKGROUND

Further optimization of the validated vertebral bone quality (VBQ) score using magnetic resonance imaging (MRI) may expand its clinical utility for bone mineral density (BMD) assessment. This study evaluated the correlations among cervical and thoracic VBQ scores, the validated Hounsfield Unit (HU) measured on computed tomography (CT), and dual-energy x-ray absorptiometry (DEXA) values.

METHODS

We retrieved the medical and radiographic records of 165 patients who underwent synchronous MRI of the cervical and thoracic spine, as well as DEXA and CT imaging of the spine obtained within 1 year of each other between 2015 and 2022. Radiographic data consisted of the MRI-based cervical and thoracic VBQ scores, CT-based HU, and DEXA T-scores of the spine and hip. Patient age, sex, body mass index (BMI), and ethnicity were also obtained.

RESULTS

Mean cervical and thoracic VBQ scores were 3.99 ± 1.68 and 3.82 ± 2.11, respectively. Mean HU and DEXA T-scores of the spine and hip were 135.75 ± 60.36, -1.01 ± 1.15, and -0.47 ± 2.27. All correlations among VBQ, HU, and DEXA were insignificant except for weak correlations between cervical and thoracic VBQ, and cervical VBQ and HU. No correlations were observed between radiographic scores and patient age or BMI. No differences based on ethnicity or sex were observed with respect to cervical or thoracic VBQ, HU, or DEXA.

CONCLUSION

Cervical and thoracic VBQ scores are distinct from Hounsfield Unit and DEXA values. VBQ scoring in the cervical and thoracic spine is not influenced by patient age, ethnicity, sex, or BMI.

Postmenopausal Osteoporosis: Menopause Hormone Therapy and Selective Estrogen Receptor Modulators

Introduction

Osteoporosis is a debilitating silent disease with a huge socio-economic impact. Prevention strategies and early detection of osteoporosis need to be carried out in every health care unit to substantially reduce the fracture rates. Indian studies have indicated a knowledge gap on diagnosis and management of osteoporosis amongst medical professionals and consumers.

Areas Covered

This article reviews the evidences available on searches from PubMed and The National Library of Medicine, author's opinions based on clinical experience. There is a need for escalating the efforts to bridge the knowledge gap regarding various aspects of osteoporosis amongst professionals and consumers. Three indications for postmenopausal hormone therapy (HT), which have constantly withstood the test of time, are symptom relief, urogenital atrophy, and bone health. This article specifically focuses on management of postmenopausal osteoporosis by HT alone or in combinations.

Expert Opinion

Early menopause is within 10 years of menopause and late menopause is considered beyond 10 years of menopause. HT is a cost-effective therapy in the early post menopause especially in symptomatic women at risk for osteoporosis unless contraindicated. HT prevents all osteoporotic fractures even in low-risk population. All HT preparations including low dose and non-oral routes of estrogen are effective for bone health. The bone protective effect lasts while on HT. Extended use of HT in women after 10 years of menopause with reduced bone mass is an option after detailed counselling of the risk benefit analysis compared with the other available therapies for osteoporosis. The primary therapy to prevent bone loss in women with premature menopause and secondary amenorrhea is HT. HT work up and annual follow-up is essential before prescribing HT.

Positions of The International Society for Clinical Densitometry and Their Etiology: A Scoping Review

The International Society for Clinical Densitometry convenes a Position Development Conference (PDC) every 2 to 3 years to make recommendations for guidelines and standards in the field of musculoskeletal measurement and assessment. The recommendations pertain to clinically relevant issues regarding the acquisition, quality control, interpretation, and reporting of measures of various aspects of musculoskeletal health. These PDCs have been meeting since 2002 and have generated 214 Adult, 26 FRAX, 41 pediatric, and 9 general nomenclature consideration positions, for a total of 290 positions. All positions are justified by detailed documents that present the background and rationale for each position. However, the linkage to these publications is not maintained by the ISCD or any other publication such that physicians cannot easily understand the etiology of the positions. Further, the wording of many positions has changed over the years after being reviewed by subsequent PDCs. This scoping review captures the references, changes, and timeline associated with each position through the 2019 PDC. It is meant to serve as a guide to clinicians and researchers for intelligent use and application of the positions.

Bone microstructure and volumetric bone mineral density in patients with global sagittal malalignment

PURPOSE

Sagittal spinal malalignment often leads to surgical realignment, which is associated with major complications. Low bone mineral density (BMD) and impaired bone microstructure are risk factors for instrumentation failure. This study aims to demonstrate differences in volumetric BMD and bone microstructure between normal and pathological sagittal alignment and to determine the relationships among vBMD, microstructure, sagittal spinal and spinopelvic alignment.

METHODS

A retrospective, cross-sectional study of patients who underwent lumbar fusion for degeneration was conducted. The vBMD of the lumbar spine was assessed by quantitative computed tomography. Bone biopsies were evaluated using microcomputed tomography (μCT). C7-S1 sagittal vertical axis (SVA; ≥ 50 mm malalignment) and spinopelvic alignment were measured. Univariate and multivariable linear regression analysis evaluated associations among the alignment, vBMD and μCT parameters.

RESULTS

A total of 172 patients (55.8% female, 63.3 years, BMI 29.7 kg/m2, 43.0% with malalignment) including N = 106 bone biopsies were analyzed. The vBMD at levels L1, L2, L3 and L4 and the trabecular bone (BV) and total volume (TV) were significantly lower in the malalignment group. SVA was significantly correlated with vBMD at L1-L4 (ρ = -0.300, p < 0.001), BV (ρ = - 0.319, p = 0.006) and TV (ρ = - 0.276, p = 0.018). Significant associations were found between PT and L1-L4 vBMD (ρ = - 0.171, p = 0.029), PT and trabecular number (ρ = - 0.249, p = 0.032), PT and trabecular separation (ρ = 0.291, p = 0.012), and LL and trabecular thickness (ρ = 0.240, p = 0.017). In the multivariable analysis, a higher SVA was associated with lower vBMD (β = - 0.269; p = 0.002).

CONCLUSION

Sagittal malalignment is associated with lower lumbar vBMD and trabecular microstructure. Lumbar vBMD was significantly lower in patients with malalignment. These findings warrant attention, as malalignment patients may be at a higher risk of surgery-related complications due to impaired bone. Standardized preoperative assessment of vBMD may be advisable.

Bone collagen quality in lumbar fusion patients: the association between volumetric bone mineral density and advanced glycation endproducts

PURPOSE

The sole determination of volumetric bone mineral density (vBMD) is insufficient to evaluate overall bone integrity. The accumulation of advanced glycation endproducts (AGEs) stiffens and embrittles collagen fibers. Despite the important role of AGEs in bone aging, the relationship between AGEs and vBMD is poorly understood. We hypothesized that an accumulation of AGEs, a marker of impaired bone quality, is related to decreased vBMD.

METHODS

Prospectively collected data of 127 patients undergoing lumbar fusion were analyzed. Quantitative computed tomography (QCT) measurements were performed at the lumbar spine. Intraoperative bone biopsies were obtained and analyzed with confocal fluorescence microscopy for fluorescent AGEs, both trabecular and cortical. Spearman's correlation coefficients were calculated to examine relationships between vBMD and fAGEs, stratified by sex. Multivariable linear regression analysis with adjustments for age, sex, body mass index (BMI), race, diabetes mellitus and HbA1c was used to investigate associations between vBMD and fAGEs.

RESULTS

One-hundred and twenty-seven patients (51.2% female, 61.2 years, BMI of 28.7 kg/m2) with 107 bone biopsies were included in the final analysis, excluding patients on anti-osteoporotic drug therapy. In the univariate analysis, cortical fAGEs increased with decreasing vBMD at (r = -0.301; p = 0.030), but only in men. In the multivariable analysis, trabecular fAGEs increased with decreasing vBMD after adjusting for age, sex, BMI, race, diabetes mellitus and HbA1c (β = 0.99;95%CI=(0.994,1.000); p = 0.04).

CONCLUSION

QCT-derived vBMD measurements were found to be inversely associated with trabecular fAGEs. Our results enhance the understanding of bone integrity by suggesting that spine surgery patients with decreased bone quantity may also have poorer bone quality.

Comparison of cervical, thoracic, and lumbar vertebral bone quality scores for increased utility of bone mineral density screening

PURPOSE

To evaluate the associations among the validated lumbar vertebral bone quality (VBQ) score, and cervical and thoracic VBQ scores.

METHODS

Radiographic records of 100 patients who underwent synchronous MRI of the cervical, thoracic, and lumbar spine were retrieved. DEXA-validated lumbar VBQ was calculated using median signal intensity (MSI) of the L1-L4 vertebrae and L3 CSF. VBQ was derived as the quotient of MSI_L1-L4 divided by MSI_CSF. Cervical and thoracic VBQ were similarly obtained using C3-C6 and C5 CSF, and T5-T8 and T7 CSF, respectively. Paired sample t-tests were used to evaluate differences among regional VBQ scores. Independent sample t-tests were used to identify sex differences in VBQ. Regression models with one-way analysis of variance (ANOVA) were constructed to identify associations among all permutations of anthropometric and regional VBQ measures.

RESULTS

Mean cervical, thoracic, and lumbar VBQ scores were 3.06 ± 0.89, 2.60 ± 0.77, and 2.47 ± 0.61, respectively. Mean differences of .127 (p = 0.045) and - 0.595 (p < 0.001) were observed between thoracic and lumbar, and cervical and lumbar VBQ scores. Correlations of 0.324, 0.356, and 0.600 (p < 0.001) were found between cervical and lumbar, cervical and thoracic, and thoracic and lumbar VBQ scores. Regression with ANOVA predicting lumbar VBQ in relation to cervical and thoracic VBQ demonstrated R Square values of 0.105 and 0.360 (p < 0.001), and β coefficient values of 0.471 and 0.217 (p < 0.001), respectively.

CONCLUSION

Thoracic VBQ provides values representative of the validated lumbar VBQ score. Cervical VBQ scores are distinct from lumbar VBQ scores and do not provide adequate surrogate values of lumbar VBQ.

Bone quality in patients with osteoporosis undergoing lumbar fusion surgery: analysis of the MRI-based vertebral bone quality score and the bone microstructure derived from microcomputed tomography

BACKGROUND CONTEXT

Osteoporosis is a risk factor for instrumentation failure in spine surgery. Bone strength is commonly assessed by bone mineral density (BMD) as a surrogate marker. However, BMD represents only a portion of bone strength and does not capture the qualitative dimensions of bone. Recently, the magnetic resonance imaging (MRI)-based vertebral bone quality (VBQ) score was introduced as a novel marker of bone quality. However, it is still unclear if the VBQ score correlates with in-vivo bone microstructure.

PURPOSE

The aims of the study were (1) to demonstrate differences in MRI-based (VBQ) and in-vivo (microcomputed tomography; μCT) bone quality between osteopenic/osteoporotic and normal bone, (2) to show the correlation between VBQ, bone microstructure and volumetric BMD (vBMD), and (3) to determine the predictive value of the VBQ score for the prevalence of osteopenia/osteoporosis.

STUDY DESIGN/SETTING

Retrospective cross-sectional study.

PATIENT SAMPLE

267 patients who underwent posterior lumbar fusion surgery from 2014 to 2021 at a single academic institution. Bone biopsies were harvested intraoperatively in 118 patients.

OUTCOME MEASURES

VBMD, VBQ score, and bone microstructure parameters derived from μCT.

METHODS

Quantitative computed tomography (QCT) measurements were performed at the lumbar spine and the L1/L2 average was used to categorize patients with a vBMD ≤120mg/cm³ as osteopenic/osteoporotic. The VBQ score was determined by dividing the median signal intensity of the L1-L4 vertebrae by the signal intensity of the cerebrospinal fluid using sagittal T1-weighted MRI scans. Intraoperative bone biopsies from the posterior superior iliac spine were obtained and evaluated with μCT. VBQ scores and μCT parameters were compared between the normal and the osteopenic/osteoporotic group. Correlations between VBQ score, μCT parameters and vBMD were assessed with Spearman's correlation (ρ). Receiver operating characteristic (ROC) analysis was performed to determine the VBQ score as a predictor for osteopenia/osteoporosis. Multiple linear regression analysis with vBMD L1/L2 as outcome was used to identify independent predictors from VBQ, μCT parameters and demographics.

RESULTS

267 patients (55.8% female, age 63.3 years, BMI 29.7 kg/m²; n=118 with bone biopsy) with a prevalence of osteopenia/osteoporosis of 65.2% were analyzed. In the osteopenic/osteoporotic group the VBQ score, structured model index (SMI), and trabecular separation (Tb.Sp) were significantly higher, whereas bone volume fraction (BV/TV), connectivity density (Conn.D) and trabecular number (Tb.N) were significantly lower. There were significant correlations between VBQ and μCT parameters ranging from ρ=-.387 to ρ=0.314 as well as between vBMD and μCT parameters ranging from ρ=-.425 to ρ=.421, and vBMD and VBQ (ρ=-.300, p<.001). ROC analysis discriminated osteopenia/osteoporosis with a sensitivity of 84.7% and a specificity of 40.6% at a VBQ score threshold value of 2.18. Age, BV/TV and trabecular thickness (Tb.Th), but not VBQ, were significant independent predictors for vBMD (corrected R²=0.434).

CONCLUSIONS

This study demonstrated for the first time that the VBQ score is associated with trabecular microstructure determined by μCT. The bone microstructure and VBQ score were significantly different in patients with impaired vBMD. However, the ability to predict osteopenia/osteoporosis with the VBQ score was moderate. The VBQ score appears to reflect additional bone quality characteristics and might have a complementary role to vBMD. This enhances our understanding of the biological background of the radiographic VBQ score and might be a take-off point to evaluate the clinical utility of it as non-invasive screening tool for bone quality.

Assessing underlying bone quality in spine surgery patients: a narrative review of dual-energy X-ray absorptiometry (DXA) and alternatives

Poor bone quality and low bone mineral density (BMD) have been previously tied to higher rates of postoperative mechanical complications in patients undergoing spinal fusion. These include higher rates of proximal junctional kyphosis, screw pullout, pseudoarthrosis, and interbody subsidence. For these reasons, accurate preoperative assessment of a patient's underlying bone quality is paramount for all elective procedures. Dual-energy X-ray absorptiometry (DXA) is currently considered to be the gold standard for assessing BMD. However, a growing body of research has suggested that in vivo assessments of BMD using DXA are inaccurate and have, at best, moderate correlations to postoperative mechanical complications. Consequently, there have been investigations into using alternative methods for assessing in vivo bone quality, including using computed tomography (CT) and magnetic resonance imaging (MRI) volumes that are commonly obtained as part of surgical evaluation. Here we review the data regarding the accuracy of DXA for the evaluation of spine bone quality and describe the alternative imaging modalities currently under investigation.

Reliability of a Risk-Factor Questionnaire for Osteoporosis: A Primary Care Survey Study with Dual Energy X-ray Absorptiometry Ground Truth

(1) Purpose: Predisposing factors to osteoporosis (OP) as well as dual-source x-ray densitometry (DXA) steer therapeutic decisions by determining the FRAX index. This study examines the reliability of a standard risk factor questionnaire in OP-screening. (2) Methods: n = 553 eligible questionnaires encompassed 24 OP-predisposing factors. Reliability was assessed using DXA as a gold standard. Multiple logistic regression and Spearman's correlations, as well as the confounding influence of age and body mass index, were analyzed in SPSS (IBM Corporation, Armonk, NY, USA). (3) Results: Our study revealed low patient self-awareness regarding OP and its risk factors. One out of every four patients reported a positive history for osteoporosis not confirmed by DXA. The extraordinarily high incidence of rheumatoid arthritis and thyroid disorders likely reflect confusion with other diseases or health anxiety. FRAX-determining risk factors such as malnutrition, liver insufficiency, prior fracture without trauma, and glucocorticoid therapy did not correlate with increased OP incidence, altogether demonstrating how inaccurate survey information could influence therapeutic decisions on osteoporosis. (4) Conclusions: Contradictive results and a low level of patient self-awareness suggest a high degree of uncertainty and low reliability of the current OP risk factor survey.

Feasibility of Opportunistic Screening for Low Thoracic Bone Mineral Density in Patients Referred for Routine Cardiac CT

Despite being a frequent and treatable disease, osteoporosis remains under-diagnosed worldwide. Our study aim was to characterize the bone mineral density (BMD) status in a group of patients with symptoms suggestive of coronary artery disease (CAD) with low/intermediate risk profile undergoing routine cardiac computed tomography (CT) to rule out CAD. This cross-sectional study used prospectively acquired data from a large consecutively included cohort. Participants were referred for cardiac CT based on symptoms of CAD. Quantitative CT (QCT) dedicated software was used to obtain BMD measurements in 3 vertebrae starting from the level of the left main coronary artery. We used the American College of Radiology cut-off values for lumbar spine QCT to categorize patients into very low (<80 mg/cm3), low (80-120 mg/cm3), or normal BMD (>120 mg/cm3). Analyses included 1487 patients. Mean age was 57 years (range 40-80), and 52% were women. The number of patients with very low BMD was 105 women (14%, 105/773) and 74 men (10%, 74/714). The majority of patients with very low BMD was not previously diagnosed with osteoporosis (87%) and received no anti-osteoporotic treatment (90%). Opportunistic screening in patients referred for cardiac CT revealed a substantial number of patients with very low BMD. The majority of these patients was not previously diagnosed with osteoporosis and received no anti-osteoporotic treatment. Identification of these patients could facilitate initiation of anti-osteoporotic treatment and reduce the occurrence of osteoporosis-related complications.

Impact of Weight Loss With Intragastric Balloon on Bone Density and Microstructure in Obese Adults

The historical concept that obesity protects against bone fractures has been questioned. Weight loss appears to reduce bone mineral density (BMD); however, the results in young adults are inconsistent, and data on the effects of weight loss on bone microstructure are limited. This study aimed to evaluate the impact of weight loss using an intragastric balloon (IGB) on bone density and microstructure. Forty obese patients with metabolic syndrome (mean age 35.1 ± 7.3 yr) used an IGB continuously for 6 mo. Laboratory tests, areal BMD, and body composition measurements via dual-energy X-ray absorptiometry, and volumetric BMD and bone microstructure measurements via high-resolution peripheral quantitative computed tomography were conducted before IGB placement and after IGB removal. The mean weight loss was 11.5%. After 6 mo, there were significant increases in vitamin D and carboxyterminal telopeptide of type 1 collagen levels. After IGB use, areal BMD increased in the spine but decreased in the total femur and the 33% radius. Cortical BMD increased in the distal radius but tended to decrease in the distal tibia. The observed trabecular bone loss in the distal tibia contributed to the decline in the total volumetric BMD at this site. There was a negative correlation between the changes in leptin levels and the measures of trabecular quality in the tibia on high-resolutionperipheral quantitative computed tomography. Weight loss may negatively impact bone microstructure in young patients, especially for weight-bearing bones, in which obesity has a more prominent effect.

Effect of duration of diabetes on bone mineral density: a population study on East Asian males

BACKGROUND

The aim of the present study is to evaluate the association between BMD and type 2 DM status in middle-aged and elderly men. To investigate a possible correlation, the present study used the BMD dataset of the Korea National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2011.

METHODS

In total, 37,753 individuals participated in health examination surveys between 2008 and 2011. A total of 3383 males aged ≥50 years were eligible. They underwent BMD measurement through dual-energy X-ray absorptiometry (DXA). The fasting plasma glucose and insulin levels of participants were also measured.

RESULTS

Men with prediabetes and diabetes had significantly higher mean BMD at all measured sites than control men did, irrespective of DM status. This was confirmed by multivariable linear regression analyses. DM duration was an important factor affecting BMD. Patients with DM for > 5 years had lower mean BMD in the total hip and femoral neck than those with DM for ≤5 years. Per multivariable linear regression analyses, patients with DM for > 5 years had significantly lower mean BMD at the femoral neck than those with DM ≤5 years.

CONCLUSIONS

DM duration was significantly associated with reduced femoral neck BMD.

Effect of vertebral exclusion on TBS and FRAX calculations

Degenerative changes falsely elevate BMD; however, their impact on TBS is unclear. This study examined how spinal degenerative changes affect TBS-adjusted fracture risk (FRAX). In a majority, but not all patients in this sample, TBS decreased after exclusion of vertebrae with degenerative change. Therefore, vertebral exclusion for TBS is suggested.

INTRODUCTION

Spinal degenerative changes elevate DXA-measured BMD, but reports find trabecular bone score (TBS) relatively unaffected. However, we observed patients where degenerative changes elevated both. Consequently, this study explored whether vertebral exclusion impacts TBS and subsequently TBS-adjusted FRAX risk.

METHODS

Clinical DXA interpretations of one physician were reviewed; those with vertebrae excluded per ISCD guidance were included in this study. BMD and TBS at L1-4 and from post-exclusion vertebrae were collected and used to adjust fracture risk (FRAX).

RESULTS

Of the patients, 102 had vertebrae excluded; their mean (SD) age, BMI, and lowest T-score were 71.6 (9.5) years, 25.4 (4.5) kg/m², and - 2.8 (1.0), respectively. Compared to L1-4, vertebral exclusion lowered (p < 0.0001) mean spine BMD and TBS by 9.5 and 3.1%, respectively. Vertebral exclusion decreased TBS by 0.040, being lower in 83%. In those with lower TBS, the mean adjusted 10-year fracture risk increased (p < 0.0001) by 0.94 and 0.32% for major osteoporotic (MOF) and hip fracture, respectively, in some risk increased by up to 4%. In those with higher TBS, adjusted risk was reduced, MOF - 0.49% and hip - 0.1%.

CONCLUSION

Vertebral exclusion following ISCD recommendations generally, but not always, lowers TBS. Consequently, the impact on TBS adjusted FRAX risk is variable. In most patients, vertebral exclusion lowers TBS; in some, this could result in a relevant change in calculated fracture risk. It seems reasonable to use TBS values from evaluable vertebrae to adjust FRAX. Further research to determine if vertebral exclusion improves fracture risk prediction is needed.

Association of bone mineral density and diabetic retinopathy in diabetic subjects: the 2008-2011 Korea National Health and Nutrition Examination Survey

Because diabetic retinopathy increases fracture risk, we studied the association between bone mineral density (BMD) and diabetic retinopathy in a nationally representative sample. A significant association between the presence of diabetic retinopathy and low BMD was observed. Therefore, diabetic retinopathy might be considered as a marker of low BMD.

INTRODUCTION

Several diabetic complications, including nephropathy, retinopathy, and peripheral neuropathy, are associated with a higher fracture risk in diabetic subjects. However, in contrast to diabetic nephropathy and peripheral neuropathy, which are associated with low bone mineral density (BMD), little is known about the association between BMD and diabetic retinopathy. The aim of the present study was to determine whether the prevalence of diabetic retinopathy is associated with BMD.

METHODS

This cross-sectional study included a nationally representative sample consisting of 4357 men aged 50 years and older and 4392 postmenopausal women who participated in the Korea National Health and Nutritional Examination Survey (KNHANES) from 2008 to 2011 and underwent BMD measurement by dual-energy X-ray absorptiometry (DXA) and diabetic retinopathy assessments using seven standard gradable photographs.

RESULTS

The diabetic women with retinopathy had lower mean BMD at all measured sites than those without retinopathy, although the BMD difference between the two groups was small (3-5 %). In addition, the diabetic women with retinopathy were 2.27 times more likely to have osteoporosis following adjustments for all clinically relevant covariates. However, the prevalence of diabetes mellitus (DM) or diabetic retinopathy was not associated with the prevalence of osteoporosis in men.

CONCLUSIONS

This study has shown that the presence of diabetic retinopathy is significantly associated with a reduced BMD and increased prevalence of osteoporosis in diabetic women.

WHOLE BODY AND REGIONAL BONE MINERAL CONTENT AND DENSITY IN WOMEN AGED 20-75 YEARS

BACKGROUND

Dual-energy X-ray absorptiometry (DXA) allows measurement of whole body (WB) and regional bone mineral content (BMC) and density (BMD).

OBJECTIVE

To measure WB and regional bone area, BMC and BMD (arms, legs, ribs and pelvis) in women of different ages.

SUBJECTS AND METHODS

140 women participated (age range 20-75 yrs). Three subgroups were built: 20-44 yr (30 premenopausal women), 45-59 (80 women), and 60-75 (30 women). WB DXA was performed on a Hologic QDR 4500 A bone densitometer (Hologic Inc., Bedford MA). WB BMD T-scores were calculated by using the manufacturer-provided and the NHANES 1999-2004 reference databases, while the WB BMC Z-scores - based on the latter. Statistical analysis was performed on an IBM SPSS Statistics 19.0 for Windows platform (Chicago, IL).

RESULTS

WB BMC and BMD Z-scores were consistently lower than the reference databases showing a difference of about 0.4 - 0.5 SD. The arms, legs and ribs lost more BMC after the age of 50-55, while the pelvis - much earlier. The total decreases in BMC were highest in the pelvis (26.36 %), followed by the arms (16.81 %) and whole body (15.91 %), while the bone area decreased mostly in the pelvis (13.23 %).

CONCLUSION

The age-related declines in regional BMC, bone areas and BMD follow different patterns in appendicular and axial bones.

Creatinine and myoglobin are poor predictors of anaerobic threshold in colorectal cancer and health

AIMS

Myoglobin is a haem protein produced in skeletal muscles. Serum concentrations of myoglobin have been proposed as a surrogate marker of muscle mass and function in both cachectic cancer patients and healthy non-cancer individuals. Creatinine, a metabolite of creatine phosphate, an energy store found in skeletal muscle, is produced at a constant rate from skeletal muscle. Urinary and plasma creatinine have been used in clinical practice as indicators of skeletal muscle mass in health and disease. Our study aimed to test the hypothesis that plasma myoglobin and creatinine concentration could accurately predict skeletal muscle mass and aerobic capacity in colorectal cancer (CRC) patients and matched healthy controls and thereby an indicative of aerobic performance.

METHODS

We recruited 47 patients with CRC and matching number of healthy volunteers for this study. All participants had their body composition measured by dual-energy X-ray absorptiometry scan, aerobic capacity measured to anaerobic threshold (AT) by cardiopulmonary exercise testing and filled in objective questionnaires to assess the qualitative functions. This study was carried out in accordance with the Declaration of Helsinki, after approval by the local National Health Service (NHS) Research Ethics Committee.

RESULTS

Age-matched groups had similar serum myoglobin and creatinine concentrations in spite of differences in their aerobic capacity. AT was significantly lower in the CRC group compared with matched controls (1.18 ± 0.44 vs. 1.41 ± 0.71 L/min; P < 0.01). AT had significant correlation with lean muscle mass (LMM) among these groups, but myoglobin and creatinine had poor correlation with LMM and AT.

CONCLUSIONS

Serum myoglobin is a poor predictor of muscle mass, and serum myoglobin and creatinine concentrations do not predict aerobic performance in CRC patients or healthy matched controls.

New reference data on bone mineral density and the prevalence of osteoporosis in Korean adults aged 50 years or older: the Korea National Health and Nutrition Examination Survey 2008-2010

This cross-sectional study was performed to investigate the reference values for bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) and the prevalence of osteoporosis in the Korean population by applying domestic reference data. In total, 25,043 Korean adults ≥20 yr of age (11,792 men and 13,251 women) participated in the study. The BMDs of the total hip, femoral neck, and lumbar spine were measured by DXA (Discovery-W, Hologic Inc.), and subjects with a BMD - 2.5 standard deviations or lower than the mean BMD for young adults (20-29 yr old) were considered to have osteoporosis. When applying the new reference values determined in this study from Korean subjects, the overall prevalence of osteoporosis increased in men aged ≥50 yr compared with that provided by the DXA manufacturer from Japanese subjects (12.2% vs. 7.8%, P<0.001) and decreased in postmenopausal women aged ≥50 yr (32.9% vs. 38.7%, P<0.001). According to the findings of this study, use of the reference values provided by the DXA manufacturer has resulted in the underdiagnosis of osteoporosis in Korean men and the overdiagnosis of osteoporosis in Korean women. Our data will serve as valuable reference standards for the diagnosis and management for osteoporosis in the Korean population.

Osteoporosis in men

OBJECTIVE

To review information pertinent to bone health and osteoporosis in men.

METHODS

A review of pertinent literature was conducted.

RESULTS

Osteoporosis affects approximately 2 million men in the US and accounts for an estimated 600,000 fractures each year. There are significant differences in skeletal size and structure between men and women that account for differences in fracture incidence, location, and outcomes. Bone density testing is appropriate for men age 70 and older and younger men (50-69) who have risk factors for osteoporosis. Lifestyle management, including adequate calcium and vitamin D intake, appropriate physical activity, and avoidance of tobacco and heavy alcohol use, is appropriate for all men. Pharmacologic therapy to reduce fracture risk is advisable for men with a clinical diagnosis of osteoporosis (a spine or hip fracture) or a T-score of -2.5 or below in the spine, femoral neck, total hip or 1/3 radius; however, the majority of men at high risk will only be identified using a fracture risk assessment tool, such as FRAX. Alendronate, risedronate, zoledronic acid, denosumab, and teriparatide are Food and Drug Administration (FDA)-approved therapeutic options.

CONCLUSIONS

Osteoporosis in men presents an important public health problem with significant morbidity and mortality. There are recommended strategies for identifying men at high risk of fracture, and effective agents are available for treatment.

Dual-energy X-ray absorptiometry measured regional body composition least significant change: effect of region of interest and gender in athletes

Dual-energy X-ray absorptiometry (DXA) is widely used to evaluate body composition in athletes. Knowledge of measurement precision is essential for monitoring body composition changes over time. This study begins characterizing DXA body composition precision in 60 (30 males and 30 females) Division 1 athletes focusing on gender, regional, and tissue type differences. Two total body scans with repositioning between were performed on the same day. Least significant change (LSC) for the root-mean-square deviation (LSCRMSD) and the percent coefficient of variation (LSC%CV) for total, lean, and fat mass was calculated for 6 regions of interest. The effect of gender, region, tissue type, and mass on the standard deviation (SD) and percent coefficient of variation (%CV) between the 2 scans was evaluated using repeated measures regression analysis. Statistically significant effects of gender, region, tissue type, and mass on SD and %CV were noted. To generalize, a nonlinear positive relationship between LSCRMSD and mass and a nonlinear negative relationship between LSC%CV and mass were observed. In conclusion, DXA body composition LSC varies among genders, regions, tissues, and mass. As such, when evaluating serial body composition in athletes, especially if assessing regional change, knowledge of precision in individuals of similar body size and gender to the population of interest is needed.

Indications of DXA in women younger than 65 yr and men younger than 70 yr: the 2013 Official Positions

Dual-energy X-ray absorptiometry (DXA) is the method of choice to assess fracture risk for women 65 yr and older and men 70 yr and older. The 2007 International Society for Clinical Densitometry Official Positions had developed guidelines for assessing bone density in younger women during and after the menopausal transition and in men 50-69 yr and the 2008 National Osteoporosis Foundation (NOF) guidelines recommended testing in postmenopausal women younger than 65 yr and men 50-69 yr only in the presence of clinical risk factors. The purpose of the 2013 DXA Task Force was to reassess the NOF guidelines for ordering DXA in postmenopausal women younger than 65 yr and men 50-69 yr. The Task Force reviewed the literature published since the 2007 Position Development Conference and 2008 NOF, reviewing clinical decision rules such as the Osteoporosis Screening Tool and FRAX and sought to keep recommendations simple to remember and implement. Based on this assessment, the NOF guidelines were endorsed; DXA was recommended in those postmenopausal women younger than 65 yr and men 50-69 yr only in the presence of clinical risk factors for low bone mass, such as low body weight, prior fracture, high-risk medication use, or a disease or condition associated with bone loss.

Bone quality, as measured by trabecular bone score in patients with adrenal incidentalomas with and without subclinical hypercortisolism

Patients with adrenal incidentalomas (AIs) and subclinical hypercortisolism (SH) have increased risk of fracture independent of bone mineral density (BMD) and possibly due to reduced bone quality. The trabecular bone score (TBS) has been proposed as a index of bone microarchitecture. The aim of the study was to investigate TBS in AI. In 102 AI patients, SH was diagnosed in the presence of at least two of the following: (1) urinary free cortisol >70 µg/24 h (193.1 nmol/L); (2) cortisol after 1-mg dexamethasone suppression test (1-mg DST) >3.0 µg/dL (82.8 nmol/L); or (3) adrenocorticotropic hormone (ACTH) <10 pg/mL (<2.2 pmol/L). In patients and in 70 matched controls, BMD was measured at lumbar spine (LS) and femur (neck [FN] and total [FT]) by dual X-ray absorptiometry and TBS was assessed in the region of LS-BMD; BMD and TBS data were reported as Z-scores. In patients, vertebral deformities were assessed by radiograph. Patients with SH (n = 34) had lower LS-BMD (-0.31 ± 1.17), FT-BMD (-0.29 ± 0.91), and TBS (-3.18 ± 1.21) than patients without SH (n = 68, 0.31 ± 1.42, p = 0.03; 0.19 ± 0.97, p = 0.01; -1.70 ± 1.54, p < 0.0001, respectively) and controls (0.42 ± 1.52, p = 0.02; 0.14 ± 0.76, p = 0.02; -1.19 ± 0.99, p < 0.0001, respectively). TBS was inversely correlated with 1-mg DST (β = -0.26, t = -2.79, p = 0.006) regardless of age, LS-BMD, body mass index (BMI), and gender. The presence of fracture was associated with low TBS alone (odds ratio [OR], 4.8; 95% confidence interval [CI], 1.85-12.42, p = 0.001) and with the cluster low TBS plus low LS-BMD (OR, 4.37; 95% CI, 1.71-11.4, p = 0.002), after adjustment for age, BMI, and gender. Low TBS plus low LS-BMD showed a good specificity (79%) for predicting fractures, whereas normal TBS (ie, > -1.5) plus normal LS-BMD high specificity (88.1%) for excluding fractures. Finally, TBS predicted the occurrence of a new fracture in 40 patients followed for 24 months (OR, 11.2; 95%CI, 1.71-71.41, p = 0.012) regardless of LS-BMD, BMI, and age. In SH, bone quality, as measured by TBS, is altered. TBS is useful in detecting AI patients at risk of fractures.

A displaced femoral neck stress fracture in an amenorrheic adolescent female runner

This case demonstrates the potential serious consequences of the female athlete triad and its effects on bone. Displaced femoral neck stress fractures cause significant morbidity, and this case highlights the preventable nature of this injury. The treatment was focused on improving low energy availability, and, although challenging, improvements were made. This injury could have been prevented if the signs and symptoms of her injury had been addressed and there had been better knowledge of her risk factors. This case highlights the need for further education in the sports and health communities.

Osteoporosis in men: an Endocrine Society clinical practice guideline

OBJECTIVE

The aim was to formulate practice guidelines for management of osteoporosis in men.

EVIDENCE

We used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe the strength of recommendations and evidence quality.

CONSENSUS PROCESS

Consensus was guided by systematic evidence reviews, one in-person meeting, and multiple conference calls and e-mails. Task Force drafts were reviewed successively by The Endocrine Society's Clinical Guidelines Subcommittee and Clinical Affairs Core Committee; representatives of ASBMR, ECTS, ESE, ISCD; and members at large. At each stage, the Task Force received written comments and incorporated needed changes. The reviewed document was approved by The Endocrine Society Council before submission for peer review.

CONCLUSIONS

Osteoporosis in men causes significant morbidity and mortality. We recommend testing higher risk men [aged ≥70 and men aged 50-69 who have risk factors (e.g. low body weight, prior fracture as an adult, smoking, etc.)] using central dual-energy x-ray absorptiometry. Laboratory testing should be done to detect contributing causes. Adequate calcium and vitamin D and weight-bearing exercise should be encouraged; smoking and excessive alcohol should be avoided. Pharmacological treatment is recommended for men aged 50 or older who have had spine or hip fractures, those with T-scores of -2.5 or below, and men at high risk of fracture based on low bone mineral density and/or clinical risk factors. Treatment should be monitored with serial dual-energy x-ray absorptiometry testing.

Low fatness, reduced fat intake and adequate plasmatic concentrations of LDL-cholesterol are associated with high bone mineral density in women: a cross-sectional study with control group

BACKGROUND

Several parameters are associated with high bone mineral density (BMD), such as overweight, black background, intense physical activity (PA), greater calcium intake and some medications. The objectives are to evaluate the prevalence and the main aspects associated with high BMD in healthy women.

METHODS

After reviewing the database of approximately 21,500 BMD scans performed in the metropolitan area of São Paulo, Brazil, from June 2005 to October 2010, high BMD (over 1400 g/cm² at lumbar spine and/or above 1200 g/cm² at femoral neck) was found in 421 exams. Exclusion criteria were age below 30 or above 60 years, black ethnicity, pregnant or obese women, disease and/or medications known to interfere with bone metabolism. A total of 40 women with high BMD were included and matched with 40 healthy women with normal BMD, paired to weight, age, skin color and menopausal status. Medical history, food intake and PA were assessed through validated questionnaires. Body composition was evaluated through a GE-Lunar DPX MD + bone densitometer. Radiography of the thoracic and lumbar spine was carried out to exclude degenerative alterations or fractures. Biochemical parameters included both lipid and hormonal profiles, along with mineral and bone metabolism. Statistical analysis included parametric and nonparametric tests and linear regression models. P < 0.05 was considered significant.

RESULTS

The mean age was 50.9 (8.3) years. There was no significant difference between groups in relation to PA, smoking, intake of calcium and vitamin D, as well as laboratory tests, except serum C-telopeptide of type I collagen (s-CTX), which was lower in the high BMD group (p = 0.04). In the final model of multivariate regression, a lower fat intake and body fatness as well a better profile of LDL-cholesterol predicted almost 35% of high BMD in women. (adjusted R2 = 0.347; p < 0.001). In addition, greater amounts of lean mass and higher IGF-1 serum concentrations played a protective role, regardless age and weight.

CONCLUSION

Our results demonstrate the potential deleterious effect of lipid metabolism-related components, including fat intake and body fatness and worse lipid profile, on bone mass and metabolism in healthy women.

Prevalence and patterns of bone loss in the first year after renal transplant in South East Asian patients

BACKGROUND

Limited data are available regarding patterns of bone loss in South East Asian renal transplant patients. We aimed to determine the prevalence of low bone density and factors contributing to bone loss in Singaporean patients in the first year after renal transplant.

METHODS

Seventy-nine consecutive patients who underwent renal transplant were evaluated. Bone mineral density (BMD) was evaluated at 0 (baseline), and at 6 and 12 months after transplant. Baseline parathyroid hormone and vitamin D levels were also assessed. Multivariate regression models were used to investigate the relationship between the different variables and BMD.

RESULTS

Thirty-six patients (45.6%) had low BMD at baseline. Factors correlating with the low BMD were older age, postmenopausal status, and tertiary hyperparathyroidism (P<0.0005, 0.009, and 0.027, respectively). There was a linear decrease in total hip and lumbar spine BMD from baseline to 12 months, the decrease from baseline to 6 months being significant (P=0.019 for total hip and P<0.0005 for lumbar spine). Patients with tertiary hyperparathyroidism had a greater risk of decrease in BMD at 6 months compared with patients with secondary hyperparathyroidism (odds ratio=13.5, confidence interval: 1.3, 144.4) and with those who had parathyroidectomy (odds ratio=34.9; confidence interval: 2.0, 598.8).

CONCLUSIONS

The prevalence of low BMD in this population of renal transplant recipients was high. Parathyroid status was the only independent factor that correlated with low BMD at baseline and subsequent bone loss highlighting the critical role of this hormone in bone metabolism after renal transplant.

[Management of the patient with a high risk of fracture in clinical practice. Results from a survey of 174 Spanish Rheumatologists (OSTEOPAR project)]

OBJECTIVE

To collect information about diagnosis, classification and treatment of patients at high risk of fracture in the rheumatologist's practice.

MATERIAL AND METHODS

A survey was conducted among Spanish rheumatologists. The survey was aimed at gathering data on the physician's healthcare activity, the osteoporosis (OP) and fracture risk factors considered as most relevant, the diagnostic used tests and the treatment indication according to the presence of different risk factors.

RESULTS

99.5% of rheumatologists felt that there is a group of patients with OP at high risk of fracture. Previous fracture was considered the most important risk factor, particularly in case of multiple fractures, severe fractures, hip fracture, or that occurred during treatment. Glucocorticoid treatment, older age and low bone mineral density were considered, in this order, other important risk factors. The number of vertebral fractures was considered the most relevant radiological data, followed by the fracture's chronology and severity. Most of the respondents selected teriparatide as the first treatment option in high-risk patients.

CONCLUSIONS

The definition of OP patient with high risk of fracture is not uniform in daily practice, although the majority of rheumatologists considered that having a previous fracture is the most important risk factor, followed by glucocorticoid treatment, older age and low BMD. Anabolic treatment was the approach most commonly used in OP patients with high risk of fracture.

Joint Official Positions of the International Society for Clinical Densitometry and International Osteoporosis Foundation on FRAX(®). Executive Summary of the 2010 Position Development Conference on Interpretation and use of FRAX® in clinical practice

The International Society for Clinical Densitometry (ISCD) and the International Osteoporosis Foundation (IOF) convened the FRAX(®) Position Development Conference (PDC) in Bucharest, Romania, on November 14, 2010, following a two-day joint meeting of the ISCD and IOF on the "Interpretation and Use of FRAX(®) in Clinical Practice." These three days of critical discussion and debate, led by a panel of international experts from the ISCD, IOF and dedicated task forces, have clarified a number of important issues pertaining to the interpretation and implementation of FRAX(®) in clinical practice. The Official Positions resulting from the PDC are intended to enhance the quality and clinical utility of fracture risk assessment worldwide. Since the field of skeletal assessment is still evolving rapidly, some clinically important issues addressed at the PDCs are not associated with robust medical evidence. Accordingly, some Official Positions are based largely on expert opinion. Despite limitations inherent in such a process, the ISCD and IOF believe it is important to provide clinicians and technologists with the best distillation of current knowledge in the discipline of bone densitometry and provide an important focus for the scientific community to consider. This report describes the methodology and results of the ISCD-IOF PDC dedicated to FRAX(®).

Osteoporosis in men: the value of laboratory testing

Evaluation of 234 men referred for osteoporosis found many with undiagnosed secondary causes and multiple unrecognized risk factors.

INTRODUCTION

Studies in women with postmenopausal osteoporosis suggest that many have unrecognized disorders affecting bone. Men are considered more likely to have underlying, possibly correctable causes. We studied the prevalence of risk factors, secondary causes, and laboratory abnormalities in men with and without previously known causes for osteoporosis.

METHODS

We reviewed the charts of 234 men with osteoporosis diagnosed by bone mineral density testing. In addition to screening chemistries, 25-hydroxyvitamin D, testosterone, luteinizing hormone, follicle-stimulating hormone, thyroid-stimulating hormone, and spot urinary calcium-to-creatinine ratio were measured.

RESULTS

The mean age was 70.6 years and mean weight was 76.4 kg. The mean T-score for spine, femoral neck, and forearm was -2.2, -2.4, and -2.3, respectively. Evaluation revealed secondary osteoporosis in 75% overall including hypogonadism, vitamin D deficiency, hypercalciuria, subclinical hyperthyroidism, and hyperparathyroidism. In those men with known secondary osteoporosis at the time of dual energy X-ray absorptiometry testing, additional diagnoses were found in just over half. Vitamin D deficiency and insufficiency were very common, and other common risk factors for osteoporosis included age >65, current smoking, and prior fracture. Half of the subjects had ≥ 4 risk factors.

CONCLUSION

Evaluation revealed a specific cause in about half of men thought to have primary osteoporosis. Among men with known secondary osteoporosis, additional risk factors and secondary causes were frequently identified. In conclusion, a relatively modest evaluation of men with osteoporosis will often provide useful information.

Distribution of Z-scores in a University cohort with an emphasis on "high" bone mineral density

High bone mineral density (BMD) is currently not defined by the International Society for Clinical Densitometry with a specific Z-score cutoff; however, it has been suggested that a Z-score greater than or equal to 2.5 is not normal. Institutional Review Board approval was obtained. We evaluated a University dual-energy X-ray absorptiometry database over the previous 24 mo to define Z-score distributions. A Z-score greater than or equal to 2.5 was selected as the outcome event of interest in a logistic regression for adjusted odds ratio. The covariates were height; weight; body mass index (BMI); gender; menopausal status; use of female hormones; presence of insufficiency fractures after 50 yr of age; previous fractures; previous surgeries (back surgeries, vertebroplasty, or kyphoplasty); transplant history; presence of long-term chronic conditions (asthma, lupus, rheumatoid arthritis, or cystic fibrosis); eating disorder; current use of glucocorticoids; smoking status; and current and past use of osteoporosis pharmacological therapies. The study included a total of 8216 patients; 7212 (87.8%) were females, and 1044 (12.2%) were males. In the total population, 13.6% had a Z-score greater than or equal to 2.5 at the lumbar spine, femoral neck, or total hip. Only 0.2% of the males and 0.8% of the females had a Z-score greater than or equal to 2.5 at all 3 sites. The 97.5th percentiles for Z-scores in our population for men and women, respectively, were 3.4 and 3.9 at the lumbar spine, 1.5 and 2.1 at the femoral neck, and 1.6 and 2.2 at the total hip. The 99th percentile for Z-scores for men and women, respectively, were 4.9 and 4.7 at the lumbar spine, 2.4 and 2.7 at the femoral neck, and 2.2 and 2.7 at the total hip. At the lumbar spine, female gender and weight were found to be risk factors for a high Z-score (≥ 2.5). The use of glucocorticoids, bone-active medications, BMI, and smoking were significantly less likely to predict a lumbar spine Z-score greater than or equal to 2.5. A high total-hip Z-score is predicted by increasing weight, whereas those patients using bone-active medications were less likely to have high BMD at the total hip. At the femoral neck, there were no significant risk factors related to a Z-score greater than or equal to 2.5; those taking bone-active medications were significantly less likely to have a high Z-score. These data suggest that a high Z-score is common at 1 or more sites. Further research about the criteria for the diagnosis of high BMD is warranted.

Validation of the Male Osteoporosis Knowledge Quiz

The purpose of this study was to validate the six-item Men’s Osteoporosis Knowledge Quiz (MOKQ). The MOKQ asks questions about risk factors that are pertinent to men, such as the risk for developing low bone mass related to hormone treatment for prostate cancer and the importance of testosterone for bone mass. A survey was sent to 242 men with a mean age of 83.2 years. The mean number of questions answered correctly in response to the six-item MOKQ was 2.37. Convergent validity was examined by correlating the score achieved on the MOKQ with the score achieved on the total Facts on Osteoporosis Quiz. The Pearson correlation coefficient for the MOKQ and the Facts on Osteoporosis Quiz was r = .76. Reliability was demonstrated by computing a Cronbach’s alpha for the MOKQ ( r = .72). The MOKQ was found to have adequate reliability and validity in assessing older men’s knowledge about osteoporosis.

Older men's knowledge of osteoporosis and the prevalence of risk factors

It has been estimated that up to 45% of men in the United States have low bone density. Yet, only a few studies have examined men's knowledge of bone health and disease. Men's knowledge of sex-specific issues related to osteoporosis is especially not well understood. We surveyed 1535 community-dwelling men with a mean age of 79 yr. The assessed risk factors included a current diagnosis of low bone mass, positive history for fracture, recent level of physical activity, and current medications with the potential to affect bone health. Knowledge about male risk factors for osteoporosis was also assessed, including the effects of advancing age, frame size, fracture risk, calcium and Vitamin D supplementation, low testosterone level, and treatment for prostate cancer. Within this sample, only 11% of the men reported a current diagnosis of low bone mass, whereas 11% reported a prior hip fracture. Only 5% of the sample reported taking some type of Food and Drug Administration-approved medication for osteoporosis. In the aggregate, the participating men answered only 39% of the 6 male osteoporosis-knowledge questions correctly. It is imperative that bone health promotion campaigns that have educated many women effectively now expand their focus to advance the bone health of men also.

A perspective on male osteoporosis

Osteoporosis and fragility fracture become common with advancing age in men. The incidence of osteoporosis-related fracture is similar to myocardial infarction and exceeds that of lung and prostate carcinoma combined. These fractures cause substantial morbidity, and the mortality following hip fracture is greater in men than in women. A decline in sex steroids and glucocorticoid and alcohol use, among other factors, contribute to bone loss and fracture risk. Approaches to reduce fracture risk in men are very similar to that in women - recognising and addressing muscle weakness/falls risk and optimising nutrition, with emphasis on calcium and vitamin D and medications when appropriate. Despite the high prevalence, osteoporosis remains largely undiagnosed and undertreated. Hopefully, increased recognition of male osteoporosis by health-care providers and the men themselves, in combination with recent consensus recommendations for treatment based on fracture-risk estimation, will reduce the burden of fragility fracture in men.

The official positions of the International Society for Clinical Densitometry: perceptions and commentary

The International Society for Clinical Densitometry (ISCD) periodically issues Official Positions (OPs) on the assessment of skeletal health in adults and children. OPs are recommendations regarding topics that include nomenclature, indications, acquisition, analysis, quality control, interpretation, reporting, and clinical utility of measuring bone density using different technologies. The purpose of these directives is to assist health care professionals in the practice of clinical densitometry. The OPs are established through a rigorous process of scientific literature review by ISCD task forces, each assigned to address a group of clinically relevant questions. The findings and recommendations of each task force are assessed and revised, as needed, by an international panel of experts. Recommendations that are felt to be appropriate for inclusion as ISCD OPs are sent to the ISCD Board of Directors for final approval. Despite having a major impact in the clinical application of bone densitometry, the ISCD OPs have not been universally adopted, in part because of misunderstanding of the process used to establish them and the way that they are intended for use in clinical practice. This is a review of the benefits and limitations of the ISCD OPs with emphasis on areas of controversy.

High bone mineral density is associated with high body mass index

SUMMARY

High BMD is an infrequent finding. In this retrospective cohort study of women 50 years and older, we documented a strong association between high BMD and high BMI.

INTRODUCTION

High bone mineral density (BMD) has been associated with genetic disorders and a variety of dietary, endocrine, metabolic, infectious and neoplastic diseases that in many cases warrant medical attention. Since body mass index (BMI) is closely correlated with BMD, we sought to explore the relationship between these two parameters in older women.

METHODS

We conducted a retrospective clinical cohort study of 16,500 women 50 years and older who underwent baseline BMD testing between May 1998 and October 2002. Mean T-scores and Z-scores, and the proportions of women with high BMD (T-score +2.5 or greater, Z-score +2.0 or greater), were assessed according to BMI category.

RESULTS

Higher BMI category was associated with higher mean T-scores and Z-scores at all sites (P < 0.001). The proportion of women with high BMD increased with each BMI category (P for trend <0.05). In women with a lumbar spine T-score of +2.5 or more, 43.5% were obese with BMI > 30 kg/m(2) (55.6% for the femoral neck and 73.1% for the total hip). For women with a lumbar spine Z-score of +2.0 or more, 37.2% were obese (42.0% for the femoral neck and 50.9% for the total hip). There was no evidence of a paradoxical increase in fracture rates in women with high BMD.

CONCLUSIONS

High BMD is closely associated with elevated BMI in women. This should be taken into consideration prior to initiating extensive investigations for rare pathologies.