Differences In Bone Mineral Density Research Articles

Denosumab versus alendronate in long-term glucocorticoid users: A 12-month randomized controlled trial.

To compare the efficacy of denosumab and alendronate on raising spine bone mineral density (BMD) in long-term glucocorticoid (GC) users. Adult patients receiving long-term prednisolone (≥2.5mg/day for ≥1year) were recruited and randomized to either subcutaneous denosumab (60mg/6months) or oral alendronate (70mg/week). BMD (lumbar spine, femoral neck, hip) and bone markers (serum P1NP and CTX) were measured at month 0, 6 and 12. The difference in spine BMD (primary outcome) at month 12 was compared between the two groups. 139 subjects were recruited (age 50.0±12.7years; 96% women): 69 assigned denosumab and 70 assigned alendronate. At entry, 73(53%) patients were osteoporotic and 82(59%) patients were naive to the bisphosphonates. Baseline clinical characteristics and BMD values were similar in the two groups. At month 12, a significant gain in mean BMD at the lumbar spine (+3.5±2.5%; p<0.001), hip (+0.9±2.8%; p=0.01) and femoral neck (+1.04±4.1%; p=0.047); was observed in denosumab-treated patients, whereas the corresponding change was +2.5±2.9% (p<0.001), +1.6±2.7% (p<0.001) and+1.5±3.9% (p=0.002) in the alendronate group. The spine, but not the hip or femoral neck, BMD at month 12 was significantly higher in the denosumab than alendronate group after adjustment for baseline BMD values, age, sex, osteoporosis risk factors and the cumulative prednisolone doses received in one year. The drop in P1NP and CTX was significantly higher in the denosumab than alendronate group. Frequency of adverse events (AEs), including infections, was similar in the two treatment arms. Seven patients withdrew from the study but not related to AEs. In patients receiving long-term GCs, denosumab is superior to alendronate in raising the spine BMD after 12months. Both drugs are well-tolerated.

Cross-Calibration of Prodigy and Horizon A Densitometers and Precision of the Horizon A Densitometer

We performed this study to enable a reliable transition for clinical study participants and patients from a GE Lunar Prodigy to a Hologic Horizon A dual-energy X-ray absorptiometry (DXA) scanner and to assess the reproducibility of measurements made on the new DXA scanner. Forty-five older adults had one spine, hip, and total body scan on a Prodigy dual-energy X-ray absorptiometry (DXA) scanner and 2 spine, hip, and total body scans, with repositioning, on a new Hologic Horizon A DXA scanner. Linear regression models were used to derive cross calibration equations for each measure on the 2 scanners. Precision (group root-mean-square average coefficient of variation) of bone mineral density (BMD) of the total hip, femoral neck, and lumbar spine (L1-L4), and total body fat, bone, and lean mass, appendicular lean mass, and trabecular bone score (TBS) was assessed using the International Society of Clinical Densitometry's (ISCD's) Advanced Precision Calculation Tool. Correlation coefficients for the BMD and body composition measures on the 2 scanners ranged from 0.94 to 0.99 (p<0.001). When compared with values on the Prodigy, mean BMD on the Horizon A was lower at each skeletal site (0.136 g/cm2 lower at the femoral neck and 0.169 g/cm2 lower at the lumbar spine (L1-4)), fat mass was 0.47 kg lower, and lean mass was 4.50 kg higher. Precision of the Horizon A scans was 1.60% for total hip, 1.94% for femoral neck, and 1.25% for spine (L1-4) BMD. Precision of TBS was 1.67%. Precision of total body fat mass was 2.16%, total body lean mass was 1.26%, appendicular lean mass was 1.97%, and total body bone mass was 1.12%. The differences in BMD and body composition values on the 2 scanners illustrate the importance of cross-calibration to account for these differences when transitioning clinical study participants and patients from one scanner to another.

Correlation between weight-bearing asymmetry and bone mineral density in patients with bilateral knee osteoarthritis

BackgroundAlthough unloading of the joint is related to reduction of the local bone mineral density (BMD), little attention had been paid to the relationship between loading asymmetry and side-to-side difference of BMD in patients with bilateral knee osteoarthritis (OA). The aim of the present study was to evaluate and clarify the relationship between gait parameters and bone mineral density in those patients.MethodsA total of 36 knees in eighteen patients (mean age = 73.7 ± 6.3 years, mean body mass index = 26.7 ± 3.8 kg/m2) with bilateral medial knee OA were enrolled in the present study. All subjects performed relaxed standing and level walking at our gait laboratory after informed consent was obtained. First, ground reaction force was calculated on bilateral knees during standing. The knees in each patient were divided into higher and lower force side for the definition of dominant side limb. Second, gait parameters in each subject were obtained. To analyze the factors that affect the weight-bearing distribution in both limbs, clinical data and biomechanical parameters were compared between knees. Clinical data included radiographic OA grade, femorotibial angle, and BMD at the bilateral femoral neck.ResultsKnees on higher force side were significantly more extended than on lower force side in standing (P = 0.012) and knee excursion during weight acceptance phase in gait was significantly larger in higher side than in lower side (P = 0.006), while the other parameters were not significantly different. As to the clinical data, higher force side had greater BMD, compared to lower force side. In terms of Kellgren–Lawrence scale and femorotibial angle on plain radiographs, there were no significant differences between higher and lower force side.ConclusionsBased on loading asymmetry in the present study, lower BMD was observed on Lower force side in patients with knee OA. Therefore, it is helpful for orthopedic surgeons to examine side-to-side differences of bone mineral density or extension limitation during standing for evaluation of the loading condition in patients with bilateral knee OA.

A study on Bone mineral density among asthmatic children on inhaled corticosteroids attending a tertiary care hospital at Mysuru

There are conflicting reports about the effect of ICS (inhaled corticosteroids) on BMD (bone mineral density). So, we studied the effect of long-term (>6 months) ICS therapy on BMD in asthmatic children. We hypothesised that there would be no difference in BMD among children on long-term ICS and their normal counterparts.

Drinking tea before menopause is associated with higher bone mineral density in postmenopausal women.

Though tea drinking years and menopause stages have been indicated to be related with bone mineral density (BMD), most human studies have not considered the impact of tea drinking beginning time. Whether drinking tea before or after menopause plays a role in BMD is still unclear. This study aims to analyze whether drinking tea before or after menopause influences BMD in Chinese postmenopausal women. A total of 1377 postmenopausal women under 80 years were enrolled from the baseline survey of the Lanxi Cohort Study. Participants were initially categorized into non-tea drinking, tea drinking beginning after menopause and tea drinking beginning before menopause groups. Tea drinking groups were subdivided according to tea drinking frequency, concentration and type. Multiple linear regression models were applied to evaluate associations between tea drinking before or after menopause and BMD and the impacts of tea drinking frequency, concentration and type on their associations in analyses including all participants. Interactions of tea drinking frequency, concentration and type with drinking tea before or after menopause were further analyzed. After adjusting for confounding factors, women who began drinking tea before menopause had significantly higher total and regional BMD than non-tea drinking participants and participants who began drinking tea after menopause. Differences in spine BMD were more significant among those who drank tea ≥four times per week. In addition, significant associations between tea drinking and BMD were found among participants who began drinking tea before menopause in both models, irrespective of the concentration and type of tea. No significant associations were found in subgroups of participants who began drinking tea after menopause in either model. The results indicate that drinking tea before menopause is related to higher BMD in Chinese postmenopausal women. The relationship is independent of tea drinking concentration and type.

Differential effects of abaloparatide and teriparatide on hip cortical volumetric BMD by DXA-based 3D modeling

SummaryIn postmenopausal osteoporotic women in ACTIVE, abaloparatide reduced fracture risk and increased areal bone mineral density (BMD) more than teriparatide at the hip and wrist. DXA-based 3D modeling showed significantly greater increases in hip cortical volumetric BMD with abaloparatide versus teriparatide. This may explain differences reported in aBMD by DXA.IntroductionIn ACTIVE, abaloparatide (ABL) increased bone mineral density (BMD) shown by dual-energy X-ray absorptiometry (DXA) while reducing fracture incidence in postmenopausal osteoporotic women. Changes in DXA BMD with ABL, 80 μg, were significantly greater than with open-label teriparatide (TPTD), 20 μg, at cortical sites including total hip, femoral neck, and 1/3 distal radius. The purpose of this study was to better understand the relative effects of ABL and TPTD on cortical and cancellous compartments in the proximal femur.MethodsHip DXA images from a subset of randomly selected patients in the ACTIVE trial (n = 250/arm) were retrospectively analyzed using three-dimensional modeling methods (3D-SHAPER software) to evaluate changes from baseline at months 6 and 18.ResultsSimilar significant increases in trabecular volumetric BMD (vBMD, + 9%) and cortical thickness (+ 1.5%) were observed with ABL and TPTD by 3D-DXA at 18 months. In contrast, only ABL significantly increased cortical vBMD versus baseline (+ 1.3%), and changes in both cortical vBMD and cortical surface BMD were significantly greater with ABL versus TPTD. In the TPTD group, changes in cortical vBMD were inversely correlated with changes in serum CTX (carboxy-terminal telopeptide of type I collagen) and PINP (procollagen type I N-terminal propeptide), suggesting that higher bone turnover may have attenuated cortical gains.ConclusionThese results suggest previously reported differences in areal BMD increases between ABL and TPTD may be due to differential effects on cortical vBMD. Further studies are warranted to investigate how these differences affect therapeutic impact on hip strength in postmenopausal women with osteoporosis.

Bone Mineral Density Differences Across Female Olympic Lifters, Power Lifters, and Soccer Players.

Jeon, W, Harrison, JM, Stanforth, PR, and Griffin, L. Bone mineral density differences across female Olympic lifters, power lifters, and soccer players. J Strength Cond Res 35(3): 638-643, 2021-Athletic training improves bone mineral density (BMD) through repeated mechanical loading. The location, intensity, and direction of applied mechanical pressure play an important role in determining BMD, making some sports more advantageous at improving BMD at specific regions. Thirty-seven (10 power lifters [PL], 8 Olympic lifters [OL], 8 soccer players [SP], and 11 recreationally active [RA]) women participated in a cross-sectional study. We measured lumbar spine (L1-L4), femoral neck, total-body BMD, and overall body composition (total fat mass, lean mass, percent body fat) with dual-energy x-ray absorptiometry. All athletic groups had greater total BMD than RA (p = 0.01 [PL]; p < 0.001 [OL]; p = 0.01 [SP]). Olympic lifters had the highest total BMD than all other athletic groups. Olympic lifters had the significantly greater total BMD than PL (p = 0.018), but there was no difference in total BMD between PL and SP. As compared with RA, OL showed greater BMD at both the total lumbar spine (p = 0.002) and the femoral neck (p = 0.007), whereas PL showed greater BMD only for the total lumbar spine (p = 0.019) and SP showed greater BMD only for the femoral neck (p = 0.002). Olympic-style lifting includes both high-impact and odd-impact loading modalities that are associated with the highest BMD at both the lumbar spine and femoral neck.

Effectiveness of electroacupuncture as a treatment for osteoporosis: A systematic review and meta-analysis.

Background:Osteoporosis (OP) results in an increased risk of fragility fractures, representing a major public health problem. In preventing OP, complementary and alternative medicine, such as acupuncture, was recommended because of the low efficiency and side effects of medications. Recently, there is insufficient evidence on electroacupuncture as an effective therapy for OP management. Hence, we evaluated the effectiveness of electroacupuncture for OP treatment.Methods:We conducted a systematic review and meta-analysis of clinical studies on patients with OP. Five databases (PubMed, Embase, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, and Wanfang) were searched from the earliest publication date to March 12, 2020. Randomized controlled trials (RCTs) were included if electroacupuncture was applied as the sole treatment or as an adjunct to other treatments compared with medications in patients with OP. The measurement outcomes included serum aminoterminal propeptide of type I procollagen (PINP) and C-telopeptide of type I collagen (CTX) levels, bone mineral density (BMD) of lumbar, and visual analog scale scores for OP-related pain. Acupoints were extracted when available.Results:In total, 11 RCTs involving 731 participants were included for further meta-analysis. The meta-analysis showed that the use of electroacupuncture as a sole treatment or as an adjunct to other treatments could relieve OP-related pain compared with medications [mean difference (MD) = −0.58, 95% confidence interval (CI); MD = −0.97 to −0.19, P = .003, I2 = 88%; MD = −1.47, 95% CI = –2.14 to −0.79, P < .001, I2 = 96%). Meanwhile, the results showed a favorable effect of electroacupuncture on decreasing serum beta-CTX levels. However, there were no significant differences in serum PINP levels and BMD of lumbar. Shenshu (BL23) was the most frequent acupoint stimulation among these studies.Conclusions:The application of electroacupuncture as an independent therapy or as an adjunct to other treatments might attenuate OP-related pain and serum beta-CTX levels. However, to overcome the methodological shortcomings of the existing evidence, due to a small size of samples and high risk of bias in these included RCTs, further rigorous studies are required.

Total bone mineral density is inversely associated with stroke: a family osteoporosis cohort study in rural China.

The relationship of osteoporosis and stroke is still not fully clarified. Apart from the well-known risk factors for stroke, bone mineral density (BMD) has gained more interest in recent years. To further elucidate the relationship between BMD and stroke risk, a prospective cohort study in the Chinese rural population was conducted. Retrospective analysis of a family osteoporosis cohort. Our subjects were selected from an osteoporosis cohort conducted in Anqing, China. All participants underwent a questionnaire assessment, clinical examinations and laboratory assessments. During the follow-up period, the number of people who had a stroke was recorded. Generalized estimating equation regression analysis was performed to determine the significance of the association between BMD and stroke. A total of 17868 people were included. A two-way interaction test of sex and BMD on stroke was significant (P = 0.002). There was a significant difference in BMD and stroke morbidity in the male group (P = 0.003). When BMD was assessed as quartiles and the lowest quartile was used as reference, a significantly lower risk for stroke was observed in Q2-4. Notably, no significant difference was observed in female participants with adjusted odds ratio (P > 0.05). The P-value for interaction was calculated. The body mass index (P = 0.014) and waist-to-hip ratio (P = 0.027) were found to be significantly associated with BMD and stroke risk in female participants. In Chinese rural areas, total BMD may negatively correlated with stroke, especially in men.

Comparison of Differences in Bone Mineral Density Measurement With 3 Hologic Dual-Energy X-Ray Absorptiometry Scan Modes

Bone mineral density (BMD) measurement using dual-energy X-ray absorptiometry (DXA) is considered a diagnostic parameter for osteoporosis by the World Health Organization (WHO). DXA densitometers have different scanning modes for BMD measurements, although the specific scanning modes vary based upon the manufacturer. For DXA machines manufactured by Hologic, which are used globally, a range of scanning modes exist, including but not limited to (in order of decreasing spatial resolution) Array, Fast Array, and Express Array. Only a handful of prior studies have compared the reproducibility of BMD measurements across scan modes. The present study aimed to add to this body of literature by investigating the differences in BMD measured between 3 scanning modes in Hologic DXA machines at 19 different health centers. As part of cross-calibration activities for two multi-center studies in China measuring BMD, the European spine phantom (ESP, 1.000 g/cm2) was scanned on 19 different Hologic DXA machines. To measure differences in BMD between the 3 scan modes most commonly found on the Hologic models available (i.e., Array, Fast Array, Express Array), the ESP measurement was performed 10 times for each scan mode on each Hologic DXA machine. One-sample t test was used to compare the average difference between the measured ESP results of the 3 scanning modes at each hospital and reference ESP values. Single factor analysis of variance was performed to compare the average differences between the pairs of scanning modes using the reference ESP. Statistically significant differences between the measured ESP results with reference ESP values were found with each scanning mode at 19 hospitals (all p values <0.05). Consistent with this finding, differences in average BMD between the Array mode and Fast Array mode were invariably the smallest compared to differences seen between the other two pairs of scan modes. Significant differences were observed between average ESP BMD for the Array and Express Array scan modes (0.971 ± 0.013 vs 0.935 ± 0.027, p < 0.001), and between Fast Array and Express Array scan modes (0.972 ± 0.012 vs 0.935 ± 0.027, p < 0.001). However, no significant difference in average ESP BMD was observed between the Array and Fast Array scan modes (0.971 ± 0.013 vs 0.972 ± 0.012, p = 0.997). The selection of ideal scanning mode requires a balance of scanning time, radiation exposure, and measurement accuracy. In this ex vivo study, the Fast Array scanning mode appeared to be a reasonable choice compared with Array and Express Array for BMD measurements by Hologic DXA. Future in vivo studies can help guide the clinical application of these findings.

Is preoperative glenoid bone mineral density associated with aseptic glenoid implant loosening in anatomic total shoulder arthroplasty?

BackgroundAseptic loosening of glenoid implants is the primary revision cause in anatomic total shoulder arthroplasty (aTSA). While supported by biomechanical studies, the impact of glenoid bone quality, more specifically bone mineral density (BMD), on aseptic glenoid loosening remains unclear. We hypothesized that lower preoperative glenoid BMD was associated with aseptic glenoid implant loosening in aTSA.MethodsWe retrospectively included 93 patients (69 females and 24 males; mean age, 69.2 years) who underwent preoperative non-arthrographic shoulder computed tomography (CT) scans and aTSA between 2002 and 2014. Preoperative glenoid BMD (CT numbers in Hounsfield unit) was measured in 3D using a reliable semi-automated quantitative method, in the following six contiguous volumes of interest (VOI): cortical, subchondral cortical plate (SC), subchondral trabecular, and three successive adjacent layers of trabecular bone. Univariate Cox regression was used to estimate the impact of preoperative glenoid BMD on aseptic glenoid implant loosening. We further compared 26 aseptic glenoid loosening patients with 56 matched control patients.ResultsGlenoid implant survival rates were 89% (95% confidence interval CI, 81–96%) and 57% (41–74%) at 5 and 10 years, respectively. Hazard ratios for the different glenoid VOIs ranged between 0.998 and 1.004 (95% CI [0.996, 1.007], p≥0.121). Only the SC VOI showed significantly lower CTn in the loosening group (622±104 HU) compared with the control group (658±88 HU) (p=0.048), though with a medium effect size (d=0.42). There were no significant differences in preoperative glenoid BMD in any other VOI between patients from the loosening and control groups.ConclusionsAlthough the preoperative glenoid BMD was statistically significantly lower in the SC region of patients with aseptic glenoid implant loosening compared with controls, this single-VOI difference was only moderate. We are thus unable to prove that lower preoperative glenoid BMD is clearly associated with aseptic glenoid implant loosening in aTSA. However, due to its proven biomechanical role in glenoid implant survival, we recommend extending this study to larger CT datasets to further assess and better understand the impact of preoperative glenoid BMD on glenoid implant loosening/survival and aTSA outcome.

The efficacy and safety of bisphosphonate analogs for treatment of osteoporosis after spinal cord injury: a systematic review and meta-analysis of randomized controlled trials.

Rapid bone loss in the early stages of spinal cord injury (SCI) leads to an increased risk of osteoporotic fracture. A meta-analysis was conducted to assess the efficacy and safety of bisphosphonates for the treatment of osteoporosis after SCI. A literature search of the PubMed, EMBASE, Cochrane Library, and Web of Science databases identified nine randomized controlled trials with 206 individuals. This meta-analysis was performed using a random-effects model. The primary outcome was the percent change in bone mineral density (BMD) of the total hip, distal femur, and lumbar spine from baseline to 12 months. Bone turnover markers were secondary outcomes. The incidences of adverse events were assessed in order to evaluate safety. There were significant differences in BMD of the total hip and lumbar spine or serum C-terminal telopeptide between the bisphosphonate and control groups but no difference in adverse events. The percent change in BMD of the distal femur and serum type 1 procollagen N-terminal peptide from baseline to 12 months was not superior in the treatment groups. Osteoclast-mediated bone resorption was inhibited by bisphosphonate administration. Subgroup analyses of participants treated with zoledronate at different sites revealed a beneficial effect on BMD of the total hip and lumbar spine but not the distal femur. Early bisphosphonate administration after SCI was safe and beneficial to the BMD of the total hip and lumbar spine at 12 months.

Dominant and non-dominant arm bone mineral density of racquet athletes

Background and Purpose: The upper extremities, especially the arms and shoulders, are used intensively in racquet sports. In this work, our primary aim is to compare bone mineral densities (BMDs) between dominant and non-dominant arms in racquet athletes. We then compare BMDs between athletes playing racquet sports and non-athletes. Methods: A total of 24 racquet sports male athletes active for at least 10 years (age, 22.46 ± 2.41 years) and 22 non-athletes (age, 21.45 ± 1.74 years) voluntarily participated in this study. The BMDs of the humerus, radius, and ulna of the dominant and non-dominant arms of both groups were measured by dual energy X-ray absorptiometry. Results: The BMDs of the proximal humerus and humeral shaft of dominant arms were significantly higher than those of non-dominant arms in athletes (19.85% vs. 12.02%); while statistically, no statistically significant difference in BMDs was found in non-athletes (P &gt; 0.05). The BMDs of the dominant proximal humerus and humeral shaft of athletes were higher than those of non-athletes (P &lt; 0.05). Non-dominant arm BMDs did not differ between the two groups (P &gt; 0.05). Conclusion: BMD differences observed between the right and left arms of athletes indicate that, rather than confounding factors like genotype, right-/left-handedness, participation in racquet sports may influence BMDs in the related extremities.

Bone Alkaline Phosphatase and Urine Hydroxyproline Assay in Pre and Postmenopausal Women in the State of Sikkim and its Correlation with Bone Mineral Density.

Introduction:Osteoporosis could be viewed as a metabolic disease. The WHO guidelines for diagnosing osteoporosis reflect structural damage only and not the metabolic imbalance that leads to it. Biochemical markers of bone turnover have been shown to provide valuable information for diagnosing and monitoring metabolic bone disease. The present study analyzed bone-specific alkaline phosphatase (BALP) and urinary hydroxyproline in pre- and postmenopausal women and correlated them with changes in bone mineral density (BMD) in the state of Sikkim. The study also intended to know the ethnicity-based disease burden in Sikkim.Materials and Methods:A hospital-based cross-sectional study was done at a tertiary hospital in Sikkim. Blood and 24-h urine samples from 50 premenopausal and 50 postmenopausal women were analyzed for total alkaline phosphatase (ALP), BALP, and Urine Hydroxyproline. BMD was measured using the quantitative ultrasound technique by Achilles densitometer.Results:There was a statistically significant increase in serum calcium (P = 0.01), ALP (P = 0.01), and urine hydroxyproline (P = 0.03) levels in postmenopausal women as compared to premenopausal women. Although ALP was higher in postmenopausal women, BALP isoform was more elevated in premenopausal women (P = 0.001). BMD was significantly lower in postmenopausal women (P < 0.001). It was also noted that there was a significant difference in BMD between tribal and nontribal populations (P = 0.003). Total ALP and BALP as the bone formation marker and urine hydroxyproline as a bone resorption marker added statistically significant r to BMD prediction (P < 0.05).Conclusion:In this study, BALP combined with Urine Hydroxyproline was helpful as a screening biomarker to predict osteoporosis in postmenopausal women.

U-Shaped Association between Dietary Acid Load and Risk of Osteoporotic Fractures in 2 Populations at High Cardiovascular Risk

BackgroundBone contributes to maintaining the acid-base balance as a buffering system for blood pH. Diet composition also affects acid-base balance. Several studies have linked an imbalance in the acid-base system to changes in the density and structure of bone mass, although some prospective studies and meta-analyses suggest that acid load has no deleterious effect on bone. ObjectiveThe aim of this study was to examine the associations between potential renal acid load (PRAL) and net endogenous acid production (NEAP) and the risk of osteoporotic fractures and bone mineral density (BMD) in 2 middle-aged and elderly Mediterranean populations. MethodsWe conducted a longitudinal analysis including 870 participants from the PREvención con DIeta MEDiterranea (PREDIMED) Study and a cross-sectional analysis including 1134 participants from the PREDIMED-Plus study. Participants were adults, aged 55–80 y, either at high cardiovascular risk (PREDIMED) or overweight/obese with metabolic syndrome (PREDIMED-Plus), as defined by the International Diabetes Federation, the American Heart Association, and the National Heart Association. PRAL and NEAP were calculated from validated food-frequency questionnaires. BMD was measured using DXA scans. Fracture information was obtained from medical records. The association between mean PRAL and NEAP and fracture risk was assessed using multivariable-adjusted Cox models. BMD differences between tertiles of baseline PRAL and NEAP were evaluated by means of ANCOVA. ResultsA total 114 new fracture events were documented in the PREDIMED study after a mean of 5.2 y of intervention and 8.9 y of total follow-up. Participants in the first and third PRAL and NEAP tertiles had a higher risk of osteoporotic fracture compared with the second tertile, showing a characteristically U-shaped association [HR (95% CI): 1.73 (1.03, 2.91) in tertile 1 and 1.91 (1.14, 3.19) in tertile 3 for PRAL, and 1.83 (1.08, 3.09) in tertile 1 and 1.87 (1.10, 3.17) in tertile 3 for NEAP]. Compared with the participants in tertile 1, the participants in the top PRAL and NEAP tertiles had lower BMD [PRAL: mean total femur BMD: 1.029 ± 0.007 and 1.007 ± 0.007 g/cm2; P = 0.006 (tertiles 1 and 3); NEAP: mean total femur BMD: 1.032 ± 0.007 and 1.009 ± 0.007 g/cm2; P = 0.017 (tertiles 1 and 3)]. ConclusionsThe results of our study suggest that both high and low dietary acid are associated with a higher risk of osteoporotic fractures, although only high dietary acid was found to have a negative relation to BMD in senior adults with existing chronic health conditions. This trial was registered at http://www.isrctn.com/ as ISRCTN3573963 (PREDIMED) and ISRCTN89898870 (PREDIMED-Plus).

Bone mineral density in Canadian children with severe haemophilia A or B: a cross-sectional study

Abstract Background Previous research has shown that bone mineral density (BMD), a measure of bone strength, may be lower among people with haemophilia. However, the majority of this research has been done in adults and in countries where the treatment for haemophilia differs from the standard of care in Canada, and there is a lack of paediatric data. Aims The primary objective of this study was to determine whether Canadian children and youth with severe haemophilia A and B have BMD similar to healthy controls matched for height, age and weight (HAW-score). Secondary objectives included the exploration of any association between BMD and the following variables: factor replacement regimen, Hemophilia Joint Health Score (HJHS), bleeding history, physical activity level, and dietary intake of calcium, vitamin D, vitamin K and protein. Methods A cross-sectional observational study was designed to determine the BMD of children with severe haemophilia A and B in Canada. Ethical approvals were obtained from participating institutions. Thirty-eight participants aged 3–18 with severe haemophilia A and B were recruited from two treatment centres in Canada. Subjects underwent dual-energy X-ray absorptiometry (DXA) scan, and data was collected from regular clinic visit to identify factor replacement regimen, HJHS, and number of joint bleeds over the lifespan. Physical activity level and dietary intake of calcium, vitamin D, vitamin K and protein were identified using self-report questionnaires. Results Participants showed a mean spine BMD Z-score and HAW-score higher than controls, with no participants showing a spine Z-score or HAW-score of &lt;0. Hip BMD score was within normal range, and 2 participants had a Z-score and HAW-score of &lt;−2. Total body BMD score was lower than controls, with 6 participants having a Z-score of &lt;−2.0, and 3 participants having a HAW-score of &lt;−2.0. Factor replacement regimen, HJHS, calcium intake, and physical activity level had no relationship to BMD Z-score or HAW-score. Low intake of vitamin D was associated with a low hip and spine BMD Z-score and HAW-score. Participants with a HJHS joint score greater than 0 had a higher total body HAW-score than those who had a joint score of 0. Conclusion Canadian children with severe haemophilia A and B demonstrate differences in spine and total body BMD from height-, age-, and weight-matched controls, where spine BMD is higher than controls and total body BMD is lower than controls. Studies with a larger sample size are needed to clarify the status of BMD in children with haemophilia treated with primary prophylaxis.

Musculoskeletal profile of amateur combat athletes: body composition, muscular strength and striking power

Background: Previous research highlighted positive musculoskeletal adaptations resulting from mechanical forces and loadings distinctive to impacts and movements with sports participation. However, little is known about these adaptations in combat athletes. The aim of this study was to quantify bone mineral density, lean muscle mass and punching and kicking power in amateur male combat athletes. Methods: Thirteen male combat athletes (lightweight and middleweight) volunteered all physiological tests including dual energy X-ray absorptiometry for bone mineral density (BMD) segmental body composition (lean muscle mass, LMM), muscle strength and striking power, sedentary controls (n = 15) were used for selected DXA outcome variables. Results: There were significant differences (p &lt; 0.05) between combat groups for lumbar spine (+5.0%), dominant arm (+4.4%) BMD, and dominant and non-dominant leg LMM (+21.8% and +22.6%). Controls had significantly (p &lt; 0.05) high adiposity (+36.8% relative), visceral adipose tissue (VAT) mass (+69.7%), VAT area (+69.5%), lower total body BMD (−8.4%) and lumbar spine BMD (−13.8%) than controls. No differences in lower limb BMD were seen in combat groups. Arm lean mass differences (dominant versus non-dominant) were significantly different between combat groups (p &lt; 0.05, 4.2% versus 7.3%). There were no differences in punch/kick power (absolute or relative) between combat groups. 5RM strength (bench and squat) correlated significantly with upper limb striking power (r = 0.57), dominant and non-dominant leg BMD (r = 0.67, r = 0.70, respectively) and total body BMD (r = 0.59). Conclusion: BMD and LMM appear to be particularly important to discriminate between dominant and non-dominant upper limbs and less so for lower limb dominance in recreational combat athletes.

995. Safety and Efficacy of F/TAF and F/TDF for PrEP in DISCOVER Participants Taking F/TDF for PrEP at Baseline

BackgroundDISCOVER is an ongoing trial comparing emtricitabine plus tenofovir alafenamide (F/TAF) or tenofovir disoproxil fumarate (F/TDF) for HIV pre-exposure prophylaxis (PrEP). DISCOVER included some participants already taking F/TDF for PrEP at baseline (BL) creating a unique opportunity to study outcomes after switching from F/TDF to F/TAF.MethodsMen who have sex with men and transgender women at risk of HIV were randomized to receive blinded daily F/TAF or F/TDF and followed for at least 96 weeks; participants taking BL F/TDF for PrEP could enroll without a washout period. Laboratory assessments included estimated glomerular filtration rate (eGFR), markers of renal proximal tubular function (RBP and β2M to creatinine ratios), and fasting cholesterol levels; these were analyzed by 2-sided Wilcoxon rank sum test. Bone mineral density (BMD) was assessed in a subset of participants and analyzed by ANOVA.Results905 of 5387 (16.8%) participants were on BL F/TDF for PrEP for a median duration of 399 days; baseline characteristics are found in Table 1. There was one HIV infection among BL PrEP users, in a participant randomized to F/TDF who had intermittent low adherence. Participants on BL PrEP randomized to F/TAF had improvements in eGFR and markers of proximal tubular function compared to F/TDF. Median change in BMD was not statistically different for BL PrEP users assigned to F/TAF vs F/TDF, however de novo F/TAF participants had improved BMD profiles compared to F/TDF. BL PrEP users in the F/TAF arm had increases in LDL cholesterol (median +6mg/dL) compared to F/TDF, while changes in HDL and total:HDL ratio were similar. Lipid-modifying agent (LMA) initiation in BL PrEP users was more frequent in the F/TAF arm, while LMA initiation in de novo PrEP participants was similar between arms (Table 2).Table 1. Characteristics of DISCOVER participants Table 2. Efficacy and safety results ConclusionHIV incidence was low in participants taking BL PrEP. Participants who switched from F/TDF to F/TAF had improvements in renal biomarkers. There was no statistical difference in BMD among BL PrEP users, although numbers were small. The observed lipid changes in BL PrEP users are consistent with the LDL and HDL suppressive effect of TDF, and the small but higher rate of LMA initiation with F/TAF is likely related to withdrawal of this effect.Disclosures Thomas Campbell, MD, Gilead Sciences Inc. (Scientific Research Study Investigator) Amanda Clarke, MD, Gilead Sciences Inc. (Consultant, Scientific Research Study Investigator, Other Financial or Material Support, Conference attendance sponsorship)Viiv Healthcare (Consultant, Other Financial or Material Support, Conference travel sponsorship) Benoit Trottier, MD, AbbVie (Grant/Research Support, Other Financial or Material Support, Personal fees)Bristol-Myers Squibb (Grant/Research Support, Other Financial or Material Support, Personal fees)Gilead Sciences Inc. (Grant/Research Support, Scientific Research Study Investigator, Other Financial or Material Support, Personal fees)Janssen (Grant/Research Support, Other Financial or Material Support, Personal fees)Merck (Grant/Research Support, Other Financial or Material Support, Personal fees)Viiv Healthcare (Grant/Research Support, Other Financial or Material Support, Personal fees) Christoph C. Carter, MD, Gilead Sciences Inc. (Employee, Shareholder) Yongwu Shao, PhD, Gilead Sciences Inc. (Employee, Shareholder) Ramin Ebrahimi, MSc, Gilead Sciences Inc. (Employee, Shareholder) Moupali Das, MD, Gilead Sciences Inc. (Employee, Shareholder) Diana M. Brainard, MD, Gilead Sciences (Employee) Jay Gladstein, MD, Gilead Sciences Inc. (Scientific Research Study Investigator)

Bone densitometry by radiofrequency echographic multi-spectrometry (REMS) in acromegaly patients.

Radiofrequency echographic multi-spectrometry (REMS) is a recently introduced non-ionising technology employed in the evaluation of osteoporosis. The aim of our study was to compare bone mineral density (BMD) in acromegaly patients and healthy controls by performing novel REMS densitometry. The second objective was to analyse the correlation between results of REMS and classical dual-energy X-ray absorptiometry (DXA) in acromegaly patients. We enrolled 33 patients with acromegaly (AG) and 24 controls (CG). The acromegaly patients were divided into two subgroups: well-controlled acromegaly (WCA) and surgery-cured acromegaly (SCA). REMS was performed in all participants, while DXA was performed only in the acromegaly group. IGF-I and GH levels were measured in acromegaly patients. Bone mineral density of the lumbar spine (LS) and the femoral neck (FN) obtained from REMS did not reveal significant differences between AG, CG, WCA, and SCA. Similarly, there were no significant differences in BMD measured by DXA at the LS and at the FN between WCA and SCA. Significant positive correlations between IGF-I concentrations and BMD obtained from both REMS and DXA were detected in the AG and WCA. In the AG and WCA, there were positive correlations between T-scores and LS BMD obtained from both methods. Radiofrequency echographic multi-spectrometry is a potential method in assessment of bone status in acromegaly. Further studies with participation of active disease patients are needed.

Disparity in bone mineral density of males and females with age

Decline in bone mass with aging leads to osteoporosis and fragility fractures. It has profound effect on the morbidity and health quality of the elderly, creating financial burden on the society. Usually, age related loss in bone mass goes undiagnosed until a fragility fracture occurs. It was observed that the bone mineral density (BMD) was found to be lesser in females compared to males in all age groups. There were significant BMD differences between males and females from age 41 yrs and above, BMD declined with age in both males and females. The maximum decline was observed in age group of 41 yrs -50 yrs compared to the control group of 20 yrs-30 yrs. The decrease in BMD was highly noticeable in females, with osteoporosis from age group 51 yrs-60 yrs. It coincides with peri-menopausal and early after menopause period. In males osteoporosis was not observed until the age of 80yrs, though osteopenia have been observed from 41 yrs onwards. There is a paramount need of awareness about detrimental effects of aging on BMD in order to bring about necessary lifestyle changes and follow therapeutic measures. This enables us to attain higher peak bone mass and maintain higher bone densities.