Dual X-ray Absorptiometry Scans Research Articles

Characteristics of subsequent contralateral proximal femoral fracture: more convenient access is needed to treat osteoporosis

BackgroundPatients with proximal femoral fracture (PFF) have high mortality and many complications. Osteoporosis increases the risk of subsequent fractures, leading to subsequent contralateral PFF. This study was performed to analyze the features of individuals with subsequent PFF following surgical therapy of first PFF and to ascertain whether such patients received an examination or treatment of osteoporosis. The reasons for lack of examination or treatment were also analyzed.MethodsThis retrospective study involved 181 patients with subsequent contralateral PFF who underwent surgical treatment in Xi'an Honghui hospital from September 2012 to October 2021. The patients’ sex, age, hospital day, mechanism of injury, surgical procedure, fracture interval, fracture type, fracture classification, and Singh index of the contralateral hip at the time of the initial and subsequent fractures were recorded. Whether the patients took calcium and vitamin D supplements, used anti-osteoporosis medication, or underwent a dual X-ray absorptiometry (DXA) scan was recorded, as was the start time of each. Patients who had never undergone a DXA scan or received anti-osteoporosis medication took part in a questionnaire.ResultsThe 181 patients in this study comprised 60 (33.1%) men and 121 (66.9%) women. Patients with initial PFF and subsequent contralateral PFF had a median age of 80 years (range 49–96 years) and 82 years (range 52–96 years), respectively. The median fracture interval was 24 (7–36) months. Contralateral fractures occurred at the highest incidence between 3 months and 1 year (28.7%). The Singh index was not significantly different between the two fractures. In 130 (71.8%) patients, the fracture type was the same. No significant difference was found in the fracture type or fracture stability classification. A total of 144 (79.6%) patients had never received a DXA scan or anti-osteoporosis medication. The main reason for not treating osteoporosis further was concern about the safety of drug interactions (67.4%).ConclusionsPatients with subsequent contralateral PFF were of advanced age, had a higher proportion of intertrochanteric femoral fractures, had more severe osteoporosis, and had longer hospital stays. The difficulty managing such patients requires multidisciplinary involvement. Most of these patients were not screened or formally treated for osteoporosis. Advanced-age patients with osteoporosis need reasonable treatment and management.

Prediction of whole body composition utilizing cross-sectional abdominal imaging in pediatrics.

Although body composition is an important determinant of pediatric health outcomes, we lack tools to routinely assess it in clinical practice. We define models to predict whole-body skeletal muscle and fat composition, as measured by dual X-ray absorptiometry (DXA) or whole-body magnetic resonance imaging (MRI), in pediatric oncology and healthy pediatric cohorts, respectively. Pediatric oncology patients (≥5 to ≤18 years) undergoing an abdominal CT were prospectively recruited for a concurrent study DXA scan. Cross-sectional areas of skeletal muscle and total adipose tissue at each lumbar vertebral level (L1-L5) were quantified and optimal linear regression models were defined. Whole body and cross-sectional MRI data from a previously recruited cohort of healthy children (≥5 to ≤18 years) was analyzed separately. Eighty pediatric oncology patients (57% male; age range 5.1-18.4 y) were included. Cross-sectional areas of skeletal muscle and total adipose tissue at lumbar vertebral levels (L1-L5) were correlated with whole-body lean soft tissue mass (LSTM) (R2 = 0.896-0.940) and fat mass (FM) (R2 = 0.874-0.936) (p < 0.001). Linear regression models were improved by the addition of height for prediction of LSTM (adjusted R2 = 0.946-0.971; p < 0.001) and by the addition of height and sex (adjusted R2 = 0.930-0.953) (p < 0.001)) for prediction of whole body FM. High correlation between lumbar cross-sectional tissue areas and whole-body volumes of skeletal muscle and fat, as measured by whole-body MRI, was confirmed in an independent cohort of 73 healthy children. Regression models can predict whole-body skeletal muscle and fat in pediatric patients utilizing cross-sectional abdominal images.

Methods over Materials: The Need for Sport-Specific Equations to Accurately Predict Fat Mass Using Bioimpedance Analysis or Anthropometry.

Bioelectrical impedance analysis (BIA) and anthropometry are considered alternatives to well-established reference techniques for assessing body composition. In team sports, the percentage of fat mass (FM%) is one of the most informative parameters, and a wide range of predictive equations allow for its estimation through both BIA and anthropometry. Although it is not clear which of these two techniques is more accurate for estimating FM%, the choice of the predictive equation could be a determining factor. The present study aimed to examine the validity of BIA and anthropometry in estimating FM% with different predictive equations, using dual X-ray absorptiometry (DXA) as a reference, in a group of futsal players. A total of 67 high-level male futsal players (age 23.7 ± 5.4 years) underwent BIA, anthropometric measurements, and DXA scanning. Four generalized, four athletic, and two sport-specific predictive equations were used for estimating FM% from raw bioelectric and anthropometric parameters. DXA-derived FM% was used as a reference. BIA-based generalized equations overestimated FM% (ranging from 1.13 to 2.69%, p &lt; 0.05), whereas anthropometry-based generalized equations underestimated FM% in the futsal players (ranging from -1.72 to -2.04%, p &lt; 0.05). Compared to DXA, no mean bias (p &gt; 0.05) was observed using the athletic and sport-specific equations. Sport-specific equations allowed for more accurate and precise FM% estimations than did athletic predictive equations, with no trend (ranging from r = -0.217 to 0.235, p &gt; 0.05). Regardless of the instrument, the choice of the equation determines the validity in FM% prediction. In conclusion, BIA and anthropometry can be used interchangeably, allowing for valid FM% estimations, provided that athletic and sport-specific equations are applied.

Dual X-ray absorptiometry-derived total and regional body volume.

Although dual X-ray absorptiometry (DXA) has been used to determine total body volume, using DXA to determine regional (i.e., arm and leg) volumes needs further assessment. Thus, the aim of the present study is to evaluate the validity of total and regional DXA-derived body volume compared to a traditional method for measuring body volume. A total of 30 males and females (Age: 25.9±4.0yrs; Height: 1.75±0.10m; Weight: 70.98±14.02kg) underwent one whole body DXA scan, underwater weighing, and regional measures of volume via water displacement. Manually created DXA region of interest boxes were used to determine regional DXA body composition. Total body volume was calculated by taking the participant's dry weight and dividing it by the average density from underwater weighing. Linear regression models with body volume from underwater weighing for total body volume and water displacement for regional volume as the dependent variable and DXA lean mass, fat mass, and bone mass as independent variables created total and regional DXA-derived body volume. T-tests assessed DXA-derived body volume to the traditional method of body volume assessment. Regression models were cross-validated using the Repeated k-fold Cross Validation method. DXA-derived total body volume was not significantly (p=0.999) different from total body volume measured via total body water displacement. In addition, both arm and leg regional DXA-derived volume was not significantly different (p=0.999) compared to regional volume measured by regional water displacement. Cross-validation of each model produced R2 values of 0.992, 0.923, and 0.932 for total body, arm, and leg, respectively. The DXA may be used as valid method for estimating total and regional body volume. Thus, these results expand the DXA's capabilities and potentially allow for a convenient regional four-compartment model with DXA-derived regional volume.

Bone health risk assessment in a clinical setting: an evaluation of a new screening tool for active populations

Introduction: Risk factors for poor bone health are not restricted to older, sedentary populations for whom current screening is focused. Furthermore, access to dual X-ray absorptiometry scanning can be limited in clinical practice. The purpose of the current study was to develop a bone health-screening tool suitable for inclusion of both younger and active populations, combined with assessing bone health with radiofrequency echographic multi spectrometry technology (REMS). Methodology: Participants (n=88) attending a physiotherapy clinic in the UK was recruited to the study: 71 women (mean age 41.5 SD 14.0 years); 17 men (mean age 40.2 SD 14.9 years). Participants completed an online bone health-screening questionnaire developed specifically for this study covering a range of lifestyle, physiological factors, combined with medical interview and received bone mineral density (BMD) measurement at the lumbar spine and femoral neck using REMS. Results: Scoring of the bone health-screening questionnaire produced a distribution of bone health scores, with lower scores suggesting a higher risk for poor bone health. In women, scores ranged from -10 to +12, mean score 2.2 (SD 4.8). In men, scores ranged from 0 to 12, mean score 6.9 (SD 3.2). A positive correlation was observed between the bone health score derived from the questionnaire and lumbar spine and femoral neck BMD Z-scores (p&lt;0.01). Conclusions: This new and comprehensive bone health-screening questionnaire with interview was effective in identifying active individuals at risk of bone fragility, who might be missed by current screening methods. The use of REMS technology to measure bone health was feasible in the clinical setting.

P.81 Nutritional status and bone health in pediatric patients with low skeletal muscle mass

Children with low skeletal muscle mass caused by neuromuscular disorders (NMDs) or cerebral palsy (CP) have altered body composition and many are wheelchair dependent. Feeding and swallowing issues are frequently reported, and they are at increased risk of malnutrition and nutrient deficiencies. Poor nutrition, physical inactivity or use of glucocorticoids also increase the risk of osteoporosis in the patient group. The aim of the study was to conduct a vitamin-, nutritional, and bone health screening in children with low skeletal muscle mass due to CP and NMDs followed in our clinic. In an observational study, a total of 66 patients < 18 years were included with: spinal muscular atrophy (11), Duchenne muscular dystrophy (DMD) (23), Merosin-deficient-muscular dystrophy (5), other myopathies (3), Charcot-Marie-Tooth neuropathy (2), and CP (22). The majority of participants were moderately or severely affected by their disease, 46/66 were wheelchair dependent. The vitamin-, nutrition and bone health were assessed by dual X-ray absorptiometry scan, blood samples (vitamins, minerals, hormones, lipids), anthropometric measurements, and a three-day diet registration. The prevalence of severe underweight (BMI z-score <-3) and underweight (BMI z-score <-2) were 13% (n=9) and 6% (n=4). Furthermore, 12% (n=8) were obese (BMI z-score > 3), and 15% (n=10) were overweight (BMI z-score 2-3). The majority of overweight patients had DMD (13/18). Decreased bone mineral density (BMD) was found in 29 patients (44%) (BMD z-score <-2). Moreover, vitamin D insufficiency (vitamin D <50 nmol/L) and deficiency (vitamin D <25 nmol/L) were found in 18% (N=12) and 4.5% (N=3), respectively. Otherwise, calcium, phosphate and parathyroid hormone were in the normal range in most of the patients. Total-cholesterol and LDL-cholesterol were elevated in 8 patients (n=12%). These findings suggest that children with low skeletal muscle mass should be systemically and thoroughly assessed for malnutrition and overweight, to offer early nutritional support. As DMD boys are regularly assessed for decreased BMD, these findings suggest a need for expanding the assessment of BMD and vitamins in other NMDs and CP patients.

Are patients receiving recommended bone protection therapy after a non-hip fracture? A retrospective study of the Fracture Liaison Service at Counties Manukau District Health Board.

To review the Fracture Liaison Service (FLS) recommendations for bone protection therapy and assess treatment implementation in the community. All patients screened from 1 January to 31 March 2019 at Counties Manukau District Health Board were evaluated. Exclusion criteria included death within six months following sentinel fracture, and hip fractures, which are studied elsewhere. Patient risk factors assessed included age, gender, type of fracture, history of previous fracture, and dual X-ray absorptiometry scan results if performed. If bone protection therapy was recommended, electronic dispensing records were utilised as a proxy for treatment initiation. One hundred and sixty-nine of the 238 patients referred were included. Thirty-seven patients had evidence of a previous fragility fracture, with thirteen patients not on bone protection treatment following their prior fracture. Of the 99 patients in the study recommended bone protection therapy, 31.3% (n=31) did not have this dispensed at six months following written FLS assessment. Three of thirteen patients with a previous fragility fracture and not on bone protection treatment, still did not have this dispensed at 6 months. A high proportion of patients recommended bone protection therapy did not receive this in a timely manner, including patients with a history of repeated fracture.

Unravelling hip-spine bone mineral density discordance in people living with HIV.

In people living with HIV (PLWH), bone mineral density (BMD) discordance between the lumbar spine (LS) and femoral neck (FN) could be frequent given the high frequency of secondary osteoporosis, including HIV-related factors for bone disease. Retrospective cohort of PLWH with a dual X-ray absorptiometry scan. Hip-spine BMD discordance was defined as different T-score or Z-scores categories at LS and FN. Overall, 865 individuals (mean 49.5years, female 27%) were included. Osteoporosis diagnosis was four-to-seven times lower when both skeletal sites were affected than when considering the lowest T-score at any site (overall, 21% vs 4%). Hip-spine BMD discordance was observed in 381 (44%) individuals, it increased with age (from 43 to 52%, P = 0.032), and it was mainly due to lower LS-BMD. A lower FN-BMD was associated with older age, lower BMI (P < 0.01), and HIV-related factors, such as low CD4 + T-cell counts, duration of HIV infection, and time on antiretroviral therapy (ART). In a multivariate regression analysis, sex male (Odds Ratio, OR 4.901), hyperparathyroidism (OR, 2.364), and time on ART (OR 1.005 per month) were independently associated with discordance. A higher estimated fracture risk by FRAX equation was observed in individuals with BMD discordance due to lower FN-BMD compared to those with lower LS-BMD (+ 36% for major osteoporotic fracture, P = 0.04; + 135% for hip fracture, P < 0.01). Hip-spine BMD discordance is highly prevalent in PLWH and it is associated with classical and HIV-related risk factors, modifying the rate of osteoporosis and fracture risk estimation.

Body Fat Distribution, Glucose Metabolism, and Diabetes Status Among Older Adults: The Multiethnic Cohort Adiposity Phenotype Study.

BackgroundAs the proportion of visceral (VAT) to subcutaneous adipose tissue (SAT) may contribute to type 2 diabetes (T2D) development, we examined this relation in a cross-sectional design within the Multiethnic Cohort that includes Japanese Americans known to have high VAT. The aim was to understand how ectopic fat accumulation differs by glycemic status across ethnic groups with disparate rates of obesity, T2D, and propensity to accumulate VAT.MethodsIn 2013–2016, 1,746 participants aged 69.2 (standard deviation, 2.7) years from five ethnic groups completed questionnaires, blood collections, and whole-body dual X-ray absorptiometry and abdominal magnetic resonance imaging scans. Participants with self-reported T2D and/or medication were classified as T2D, those with fasting glucose >125 and 100–125 mg/dL as undiagnosed cases (UT2D) and prediabetes (PT2D), respectively. Using linear regression, we estimated adjusted means of adiposity measures by T2D status.ResultsOverall, 315 (18%) participants were classified as T2D, 158 (9%) as UT2D, 518 (30%) as PT2D, and 755 (43%) as normoglycemic (NG), with significant ethnic differences (P < 0.0001). In fully adjusted models, VAT, VAT/SAT, and percent liver fat increased significantly from NG, PT2D, UT2D, to T2D (P < 0.001). Across ethnic groups, the VAT/SAT ratio was lowest for NG participants and highest for T2D cases. Positive trends were observed in all groups except African Americans, with highest VAT/SAT in Japanese Americans.ConclusionThese findings indicate that VAT plays an important role in T2D etiology, in particular among Japanese Americans with high levels of ectopic adipose tissue, which drives the development of T2D to a greater degree than in other ethnic groups.

Association Between Hydration and Body-Fat Percentage in Children in Miami-Dade: Preliminary Data From the MetA-Bone Trial

ObjectivesBackground: Children 9–13 years old in the US have suboptimal hydration status, with an average water intake of 496 mL/d (adequate intake for water is 2,100 mL/d in girls and 2,400 mL/d in boys, as per the Institute of Medicine). Studies have shown a significant inverse association between hydration status and body-fat percentage in children, although most studies failed to use Dual-X-Ray Absorptiometry Scan (DXA), the gold standard for body composition. Objectives: To associate total fluid intake, hydration status, and body-fat percentage in children 10–13 years from the baseline visit of the MetA-Bone Trial, a trial to test the effect of soluble corn fiber supplementation on bone metabolism.MethodsBody-fat percentage was measured using DXA, total fluid intake (mL/day) was assessed from three 24-hour dietary recalls using the Nutrition Data System for Research (NDSR), and hydration status was objectively measured using Urine Specific Gravity (USG) via 24-h urine collections. Statistical analyses included descriptive statistics and linear regression performed with SPSS 26.0. Models were adjusted for age and sex.ResultsA total of 14 children (57.1% males) had complete data. Mean body-fat was 31.8 ± 8.53%, mean total water intake was 1634 ± 866 mL/day (54.5% were below the water adequate intake), and mean USG was 1.031 ± 0.023 (55.6% were dehydrated). Linear regression showed that total water intake and the objective hydration status were not significantly associated (β = 0.457; p = 0.216; adjusted for age and sex β = 0.461 p = 0.319). No associations were found between total water intake and body-fat percentage (β = −0.254, p = 0.452; adjusted for age and sex (β = −0.102, p = 0.758) or between objective hydration status and body-fat percentage (β = 0.009; p = 0.982; adjusted for age and sex β = −0.034; p = −0.094).ConclusionsMost children did not meet the adequate intake for water and were dehydrated. Total water intake and objective hydration status was not significantly associated among them and to body-fat percentage. A higher sample size may be necessary to find an association between hydration, body-fat percentage in children.Funding SourcesFunding was supported by the National Institute of Health (Eunice Kennedy Shriver National Institute of Child Health and Human Development, NICHD), grant number 1R01HD098589-01.

Visceral Adiposity Is Associated With Shifts in the Gut Bacterial and Phage Microbiome in Postmenopausal Women

ObjectivesMore than 40% of U.S. adults are obese. Obesity, and in particular abdominal obesity, is associated with increased risk for developing a variety of chronic diseases. Obesity, aging, and menopause are each associated with differential shifts in the gut microbiome. We examined the association of visceral adiposity tissue (VAT) and the gut bacterial and phage microbiome.MethodsWe selected postmenopausal women (mean age 78 yrs) from the extremes of VAT (n = 25 per group; low VAT area (45.6 ± 12.5 cm2) and high VAT area (179.6 ± 30.4 cm2)) using data from dual x-ray absorptiometry (DXA) scans and performed shotgun metagenomic sequencing on fecal DNA collected at the time of DXA scan. Women with history of hypertension, diabetes, hormone therapy use, or antibiotic use within 90 days from sample collection were excluded. DNA libraries were prepared using the Illumina Nextera XT library preparation kit and libraries were sequenced on an Illumina HiSeq platform to generate 150-bp paired-ends reads. We examined the α-diversity (Shannon or Chao1), principal coordinate analysis β-diversity distances, and prevalence of microbiome taxa comparing the high vs. low VAT groups.ResultsThere was no significant difference in α-diversity or β-diversity between VAT groups. At the phyla level, women with high VAT displayed elevated Bacteroidetes and Proteobacteria proportional abundance (p < 0.05). At the species level, women with low VAT displayed significantly elevated proportional abundance of Alistipes shahii, Anaerostipes hadrus, and Blautia wexlerae. Women with high VAT area displayed significantly elevated Parabacteroides distasonis, Bacteroides uniformis, and Roseburia intestinalis. Women with high VAT displayed elevated proportional abundance of Escherichia phage TL-2011b (p < 0.05).ConclusionsData suggest that postmenopausal women with high VAT display a differential bacterial microbiome and phage profile compared to postmenopausal women with low VAT, consistent with changes seen with age. Moreover, we identified an elevated proportional abundance of Alistipes shahii, Anaerostipes hadrus, and Blautia wexlerae in women with low VAT, suggesting potential for anti-obesity activity of these microbes in postmenopausal women.Funding SourcesDOD BCRP Breakthrough Award to KLC. The WHI program is funded by the NHLBI/NIH. NIDCR/NIH R01 to JW-W.

Comparison of Quantitative Computed Tomography and Dual X-Ray Absorptiometry: Osteoporosis Detection Rates in Diabetic Patients.

IntroductionDiabetes mellitus (DM) adversely affects the skeletal system and is associated with an increased risk of osteoporosis and fragility fractures. This study aimed to assess the diagnostic accuracy of quantitative computed tomography (QCT) in osteoporosis detection in patients with DM.MethodsA cross-sectional diagnostic accuracy study was conducted at the diabetic clinic of a tertiary care teaching hospital in North India. A total of 30 individuals with DM were subjected to spinal QCT and lumbar spine and hip dual x-ray absorptiometry (DXA). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and positive and negative likelihood ratios of QCT were measured against DXA and the diagnostic discordance between QCT and DXA was investigated.ResultsQCT, compared to the gold standard DXA, has a sensitivity/specificity of 92.8% (95% CI 92.4%-93.2%)/81.2% (95% CI 80.6%-81.8%). The PPV/NPV of QCT was 81.2% (95% CI 80.6%-81.8%)/92.8% (95% CI 92.4%-93.2%). The positive likelihood ratio/negative likelihood ratio was 4.95 (95% CI 4.79-5.11)/0.087 (95% CI 0.082-0.093). Area under the curve was 0.871 (95% CI 0.731-1.00). Minor diagnostic discordance was present in 36.6% of patients with diabetes.Conclusion The current study assessed the diagnostic accuracy of QCT in osteoporosis detection in people with diabetes. DXA is the gold standard diagnostic tool; however, its availability is limited. The current study showed that QCT is an excellent diagnostic tool. Based on these results, this study recommends that QCT may serve as a problem-solving investigation tool where DXA is unavailable, or it may be the primary investigation tool for bone mineral density measurement and osteoporosis detection if a dedicated DXA scanner is inaccessible. This study also recommends further investigating the feasibility of opportunistic osteoporosis screening in routine abdominal and chest CT. Finally, considering the silent nature of osteoporosis and the high prevalence of osteoporosis in individuals with diabetes, a proactive approach is required in the screening of osteoporosis.

1 Year HIIT and Omega-3 Fatty Acids to Improve Cardiometabolic Risk in Stage-A Heart Failure

ObjectivesThis study aims to determine whether 1 year of high-intensity interval training (HIIT) and omega-3 fatty acid (n-3 FA) supplementation would improve fitness, cardiovascular structure/function, and body composition in obese middle-aged adults at high-risk of heart failure (HF) (stage A). BackgroundIt is unclear if intensive lifestyle interventions begun in stage A HF can improve key cardiovascular and metabolic risk factors. MethodsHigh-risk obese adults (n = 80; age 40 to 55 years; N-terminal pro–B-type natriuretic peptide >40 pg/mL or high-sensitivity cardiac troponin T >0.6 pg/mL; visceral fat >2 kg) were randomized to 1 year of HIIT exercise or attention control, with n-3 FA (1.6 g/daily omega-3-acid ethyl esters) or placebo supplementation (olive oil 1.6 g daily). Outcome variables were exercise capacity quantified as peak oxygen uptake (V.O2), left ventricular (LV) mass, LV volume, myocardial triglyceride content (magnetic resonance spectroscopy), arterial stiffness/function (central pulsed-wave velocity; augmentation index), and body composition (dual x-ray absorptiometry scan). ResultsFifty-six volunteers completed the intervention. There was no detectible effect of HIIT on visceral fat or myocardial triglyceride content despite a reduction in total adiposity (Δ: -2.63 kg, 95% CI: -4.08 to -0.46, P = 0.018). HIIT improved exercise capacity by ∼24% (ΔV.O2: 4.46 mL/kg per minute, 95% CI: 3.18 to 5.56; P < 0.0001), increased LV mass (Δ: 9.40 g, 95% CI: 4.36 to 14.44; P < 0.001), and volume (Δ: 12.33 mL, 95 % CI: 5.61 to 19.05; P < 0.001) and reduced augmentation index (Δ: -4.81%, 95% CI: -8.63 to -0.98; P = 0.009). There was no independent or interaction effect of n-3 FA on any outcome. ConclusionsOne-year HIIT improved exercise capacity, cardiovascular structure/function, and adiposity in stage A HF with no independent or additive effect of n-3 FA administration. (Improving Metabolic Health in Patients With Diastolic Dysfunction [MTG]; NCT03448185)

Anthropometric Factors Associated With Bone Stress Injuries in Collegiate Distance Runners: New Risk Metrics and Screening Tools?

Background:Lower limb bone stress injury (BSI) of the pelvis, femur, and tibia is prevalent in collegiate track and field distance runners. Bone mineral density (BMD), body composition (BComp), and anthropometric parameters before initial collegiate injury have not been compared between runners with BSI and their noninjured counterparts.Purpose:To characterize bone health in relation to BComp and anthropometric measurements from total-body dual x-ray absorptiometry (DXA) scans in collegiate male and female distance runners before BSI and develop BMD prediction models.Study Design:Case-control study; Level of evidence, 3.Methods:Distance runners (N = 79) from a single university track and field team were retrospectively enrolled into this study. The runners completed a DXA scan during the fall season (August-November) and participated in sport activities before the scan. Three months after scanning, electronic medical records were reviewed for the occurrence of BSI. An independent-sample t test was used to compare BMD (total and regional [spine, pelvis, and legs]), BComp (% body fat, fat mass, and lean mass), and anthropometric measurements (shoulder width and leg, arm, and trunk length) between runners with versus without BSI (included subgroup analysis by sex). Multiple linear regression with stepwise removal was used to determine variables most predictive of BMD.Results:Of the 79 enrolled participants (42 male, 37 female), 18 runners (22.8%; 11 female, 7 male) sustained a lower limb BSI. Compared with the noninjured group, injured runners had lower total and regional BMD (P < .001 for all) and shorter leg and arm lengths (P < .05 for both), whereas injured male runners had lower fat mass and injured female runners had lower lean mass in the legs (P < .05 for both). Injured runners’ age-matched total BMD Z score (-0.1 ± 0.6) was considered clinically normal. BComp and anthropometric measures were predictive of total and regional BMD (P < .05; R 2 = 0.64-0.80; percentage error = 3.8%-4.8%).Conclusion:The DXA scans of injured runners prior to incidence indicated lower BMD compared with noninjured runners. Shorter limb lengths, lower fat mass (male), and lower leg lean mass (female) may also be indicative of risk. Certain BComp and anthropometric measures were predictive of BMD.

The IMAGINE Intervention: Impacting Physical Activity, Body Fat, Body Mass Index, and Dietary Inflammatory Index.

Many behavior-change interventions focused on nutrition and physical activity (PA) have been implemented to prevent disease and promote optimal health. This study examined changes in PA with Energy-adjusted Dietary Inflammatory Index (E-DII™) and chronic disease risk factors in participants of a multicomponent intervention. Data from the Inflammation Management Intervention (IMAGINE) were used. Participants self-selected into the intervention or control group. At baseline and 12 weeks (post-intervention), participants completed three unannounced 24-hour dietary recalls (24HR), anthropometric measures (height, weight), and a dual x-ray absorptiometry scan. PA was measured using Sensewear® armbands. E-DII scores were calculated from the 24HR. Descriptive statistics and t-tests summarized variables and multiple regression assessed relationships between PA and body mass index (BMI), total body fat percent, and E-DII scores. Intervention participants increased moderate-to-vigorous PA (MVPA) and lowered BMI, total body fat, and E-DII scores compared to controls. Every 10-minute increase in post-intervention MVPA was associated with 1.6 kg/m2 lower BMI (p<0.01) and 2.4% lower body fat percent (p<0.01) among control participants, after adjusting for covariates. Every 10-minute increase in post-intervention MVPA was associated with 0.3 lower (i.e., less inflammatory) post-intervention E-DII (p=0.01) scores among intervention participants, after adjusting for covariates. Participants who changed dietary intake changed PA. While changes were in expected directions, this intervention's emphasis on dietary behaviors compared to PA may have attenuated the relationship between PA and study outcomes.

Computed Tomography of the Chest as a Screening Tool for Low Bone Mineral Density.

Computed tomography (CT) Hounsfield units (HU) recently emerged as a promising screening tool for low bone mineral density (BMD). We hypothesized that CT HU measurements of the thoracic spine would significantly and positively correlate with dual X-ray absorptiometry (DXA) BMD scans of the femoral neck. The study included patients with DXA scans and thoracic CT scans at the Walter Reed National Military Medical Center. One author, blinded to the DXA scans, measured HU from the cancellous bone in T4 vertebrae. Another author statistically compared femoral neck DXA T-scores to the CT HU measurements. The study included 145 patients with CT scans and femoral neck DXAs. The osteoporotic and osteopenic groups had a significant difference in HU measurements compared to the normal group within the study (P < .0001 and .002, respectively). A low BMD screening value of 231 HU provided a sensitivity of 90.1% and negative predictive value of 85.7%. Thoracic vertebrae HU measurements correlate with a low BMD of the femoral neck as determined by DXA T-scores. A high sensitivity and negative predictive value was achieved with a screening value of 231 HU. Utilization of chest or thoracic spine CT imaging as a screening method provides a quick and available screening tool for assessing low BMD in patients with these scans.Level of Evidence: III (Diagnostic).

829. Incidence of Low BMD and Barriers to Routine Screening for Osteoporosis in HIV Patients in Eastern North Carolina

BackgroundWith HIV therapy, the life expectancy of persons with HIV (PWH) has improved and complications associated with long-standing HIV and antiretroviral drugs have become more apparent. Low bone mineral density (BMD) (defined by T score < -1) and osteoporosis (defined by T-score < -2.5) are common in PWH. In a meta-analysis of 884 HIV-infected patients, 67% had reduced BMD, of whom 15% had osteoporosis which is 3 times greater than HIV uninfected controls. IDSA guidelines recommend routine screening for osteoporosis in PWH aged ≥ 50 years, yet the rate of screening for osteoporosis in these patients remains low (7.4%-17%). This QI project aimed to estimate the frequency of and identify the barriers to screening for osteoporosis in eligible HIV patients.MethodsThis prospective observational study was conducted in the HIV clinic at East Carolina University from 2018-2019. A sample of 104 HIV patients, ≥ 50 years were selected randomly. Data regarding referral for DXA (dual X-ray absorptiometry) scan, its results, and their insurance provider was collected. The plan was to analyze the barriers associated with guideline-recommended BMD screening and implement it in eligible patients.ResultsFrom a total of 104, 89 patients (85.6%) were referred for a DXA scan. The reasons for lack of referral were obesity, insurance barrier, wheelchair-bound, and test ordered by another provider. Of the 89 patients referred for DXA, only 49 (47% of total) underwent the scan. In terms of barriers, insurance limitation was the most common reason. Out of the patients that had DXA scans, 19 (39%) were found to have low bone density and 1 had osteoporosis. Low BMD was more common in men (63%) as compared to women (37%) in this group.Percentage of patients who underwent a DXA scan and the barriers in those who didn’t Frequency of BMD screeningIncidence of Low BMD BMD resultsConclusionIn our study, 47% of patients had a BMD assessment. This is better than what has been reported in other single-center studies, however, it is not ideal. About 34% of the patients had insurance coverage as the major barrier for routine screening, as has been mentioned in other similar studies. Of the patients who underwent the DXA scan, 41 % had a low BMD. Other studies have reported variable prevalence of abnormal BMD, from 47-93%. Interestingly, the prevalence of low BMD in our cohort was close to the national average in non-HIV patients.Disclosures All Authors: No reported disclosures

Abaloparatide Effects on Cortical Volumetric BMD and Estimated Strength Indices of Hip Subregions by 3D-DXA in Women With Postmenopausal Osteoporosis

In ACTIVE, abaloparatide increased areal BMD (aBMD) of the hip and femoral neck vs teriparatide and placebo in women with osteoporosis. Previously, 3D-processing of dual X-ray absorptiometry (DXA) scans of a subgroup of ACTIVE subjects showed similar increases in trabecular volumetric BMD (Tb.vBMD) and greater increases in cortical vBMD (Ct.vBMD) of the total hip with abaloparatide vs teriparatide. The current analyses from this subgroup describe 2D- and 3D-DXA data for hip subregions. Randomly selected subjects from ACTIVE (n = 250/treatment group) who received 18 mo of placebo, abaloparatide 80 µg, or open-label teriparatide 20 µg by daily subcutaneous injection underwent hip DXA at baseline, and mo 6 and 18 of treatment. Areal BMD of the femoral neck, trochanter, and femoral shaft was determined using standard 2D-DXA and 3D-SHAPER software to retrospectively evaluate changes from baseline in volumetric parameters of these 3 hip subregions, including trabecular and cortical segmentation. Changes in biomechanical parameters cross-sectional moment of inertia (CSMI), section modulus (Z), and buckling ratio were also evaluated. Femoral neck, trochanter, and shaft aBMD increased in the abaloparatide and teriparatide groups at mo 6 and 18 vs placebo, with greater increases for abaloparatide vs teriparatide at the femoral neck at mo 6 and the shaft at mo 6 and 18. All 3 subregions showed similar significant increases in Tb.vBMD with abaloparatide and teriparatide vs placebo, whereas Ct.vBMD of all 3 subregions showed greater increases after 18 mo of abaloparatide vs teriparatide. Biomechanical parameters improved in all subregions with abaloparatide and teriparatide vs placebo, with greater improvements in CSMI and Z of the femoral neck and lower shaft after 6 and 18 mo of abaloparatide vs teriparatide. Differential femoral neck and shaft Ct.vBMD responses may explain the greater increases in CSMI and Z of those subregions with abaloparatide vs teriparatide.

New technology REMS for bone evaluation compared to DXA in adult women for the osteoporosis diagnosis: a real-life experience.

To assess the accuracy of Radiofrequency Echographic Multi Spectrometry (REMS) technology in diagnosing osteoporosis in comparison with dual X-ray absorptiometry (DXA) on a population of Brazilian women. A population of women age ranged between 30 and 80 was recruited at DXA Service of São Paulo School-Hospital, Brazil. They underwent REMS and DXA scans at the axial sites. The REMS accuracy for the osteoporosis diagnosis was evaluated in comparison with DXA on both sites. The intra-operator and inter-operator coefficient of variation (CV) was also calculated. A total of 343 patients were enrolled in the study. Erroneous scans due to poor quality acquisitions with both methods or to other technical reasons were excluded; 227 lumbar spine exams and 238 hip exams were acceptable for comparison analysis. The comparison between REMS and DXA outcomes showed that the average difference in BMD (expressed as bias±1.96 SD) was -0.026±0.179g/cm2 for the spine and -0.027±0.156g/cm2 for the femoral neck. When accepted 0.3 tolerance on T-score, there were no cases diagnosed as osteoporosis by DXA that were defined as normal by REMS. The REMS intra-operator CV was 0.51% for the lumbar spine and 1.08% for the femoral neck. The REMS inter-operator CV was 1.43% for the lumbar spine and 1.93% for the femoral neck. The REMS approach had high accuracy for the diagnosis of osteoporosis in comparison with DXA in adult women. According to our results, this new technology has shown to be a promising alternative for populations without access to DXA densitometry.

Prediction of Distal Femur and Proximal Tibia Bone Mineral Density From Total Body Dual Energy X-Ray Absorptiometry Scans in Persons with Spinal Cord Injury

Bone density decreases rapidly after spinal cord injury (SCI), increasing fracture risk. The most common fracture sites are at the knee (i.e., distal femur or proximal tibia). Despite this high fracture incidence, knee-specific scans for bone density using dual x-ray absorptiometry (DXA) were not available until 2014 and are still not routinely used in clinical practice today. This has made it difficult to determine the rehabilitation efficacy and hindered understanding of the long-term changes in knee areal bone density. The purpose of this investigation was to compare areal bone mineral density values for the knee from both total-body and knee-specific DXA scans in persons with SCI. A total of 20 participants (16 males) >1 yr-post spinal cord injury received two DXA scans; a total-body scan and a knee-specific scan. Standardized methods were used to create regions of interest to determine bone density of four regions – the epiphysis and metaphysis of the distal femur and proximal tibia – from the total-body scan. Linear regressions and Bland-Altman analyses were conducted to determine the correlation (r2) and agreement (mean bias ± 95% level of agreement) respectively between the two scan types for each region. Linear regression analyses showed strong significant (p < 0.001) relationships between the two scan types for the distal femur epiphysis (r2 = 0.88) and metaphysis (r2 = 0.98) and the proximal tibia epiphysis (r2 = 0.88) and metaphysis (r2 = 0.99). The mean bias ± 95% level of agreement were distal femur epiphysis (0.05 ± 0.1 g/cm2) and metaphysis (0.02 ± 0.04 g/cm2); proximal tibia epiphysis (-0.02 ± 0.1 g/cm2) and metaphysis (0.02 ± 0.03 g/cm2). Results suggest knee-specific bone density can be assessed using a total-body DXA scan. This may allow for more comprehensive use of DXA scans which would reduce the burden of multiple site-specific scans for persons with SCI and enable more widespread adoption of knee bone density assessment in this population.