Genome-wide association study of osteoporosis identifies genetic risk and interactions with DASH diet and sugar sweetened beverages in a Hispanic cohort of older adults

BACKGROUND

Osteoporosis (OP) and low bone mass can be debilitating and costly conditions if not acted on quickly. This disease is also difficult to diagnose as symptoms develop unnoticed until fracture occurs. Therefore, gaining understanding of the genetic risk associated with these conditions could be beneficial for healthcare professionals in early detection and prevention.

METHODS

The Boston Puerto Rican Osteoporosis (BPROS) study, an ancillary study to the Boston Puerto Rican Health Study (BPRHS), collected information regarding bone and bone health. All bone measurements were taken during regular BPROS visits using dual-energy x-ray absorptiometry. Osteoporosis was defined as T-score ≤ -2.5 (2.5 SD or more below peak bone mass). Dietary variables were collected at the second wave of the BPRHS via food frequency questionnaire. We conducted genome-wide associations with bone outcomes including bone mineral density (BMD) and OP for 978 participants. We also examined interactions with dietary quality on the relationships between genotype and bone outcomes. We further tested if candidate genetic variants described in previous GWAS on OP and BMD contribute to OP risk in this population.

RESULTS

Four variants were associated with OP: rs114829316 (IQCJ), rs76603051, rs12214684 (MCHR2), and rs77303493 (RIN2), and two variants with BMD of lumbar spine (rs11855618, CGNL1) and hip (rs73480593, NTRK2), reaching the genome-wide significance threshold of P ≤ 5E-08. In a gene-diet interaction analysis, we found that one SNP showed a significant interaction with the overall DASH score, and 7 SNPs with sugar-sweeten beverages, a major contributor to the DASH score.

CONCLUSION

This study identifies new genetic markers related to osteoporosis and BMD in older Hispanic adults. Additionally, we uncovered unique genetic markers that interact with dietary quality, specifically sugar-sweetened beverages, in relation to bone health. These findings may be useful to guide early detection and preventative care.

TC and LDL-C are negatively correlated with bone mineral density in patients with osteoporosis

OBJECTIVE

To investigate the relationships of multiple lipid metabolism indicators and bone turnover markers (BTMs) with bone mineral density (BMD) and osteoporosis, in order to identify high-risk populations.

METHODS

A total of 380 patients were recruited and their general information was collected. Linear and logistic regression models were used to analyze the correlation of these indicators with BMD and osteoporosis.

RESULTS

Lipid metabolism indices and BTMs exhibited varying degrees of positive or negative correlation with BMD. Elevated levels of triglycerides (r = -0.204, P = 0.004), total cholesterol (TC) (r = -0.244, P < 0.001), low-density lipoprotein cholesterol (LDL-C) (r = -0.256, P < 0.001), apoprotein B (r = -0.292, P < 0.001) and lipoprotein-associated phospholipase A2 (Lp-PLA2) (r = -0.221, P = 0.002) in women were associated with a reduction in BMD. This relationship persisted even after adjusting for confounding factors and in the subgroup analysis of elderly women. In males, TC (r = 0.159, P = 0.033), LDL-C (r = 0.187, P = 0.012), apoprotein B (r = 0.157, P = 0.035), and Lp-PLA2 (r = 0.168, P = 0.024) exhibited a positive correlation with BMD, while free fatty acid (FFA) (r = -0.153, P = 0.041) was negatively correlated with BMD. However, after adjusting for confounding factors, only FFA remained negatively correlated with BMD, which was not observed in the age subgroup analysis. Furthermore, elevated levels of TC and LDL-C in elderly women were positively associated with the risk of osteoporosis or low bone mass.

CONCLUSION

Elevated levels of TC and LDL-C not only indicate a decrease in BMD in females but also positively correlate with the occurrence of osteoporosis and low bone mass in elderly females.

[Comparison on Performance of Quantitative Ultrasound and Dual-Energy X-ray Absorptiometry in Evaluating Bone Health of Adults Aged 18-40 Years]

Objective To compare the consistency of quantitative ultrasound(QUS)and dual-energy X-ray absorptiometry(DXA)in measuring bone mineral density(BMD)of adults aged 18-40 years in Guangzhou and evaluate the diagnostic value of QUS for identifying low bone mass.Methods DXA was employed to measure the BMD and QUS to measure the speed of sound(SOS)in 731 participants.The Bland-Altman analysis was performed to evaluate the consistency of Z scores between SOS and BMD.With the BMD Z ≤-2.00 as the diagnostic criterion for low bone mass,the receiver operating characteristics curve of QUS was established,and the area under the curve(AUC)and the sensitivity,specificity,and correct diagnostic index for the optimal cut-off of SOS Z score were calculated.Results The results of Bland-Altman analysis showed that the mean differences in the Z scores of SOS and BMD in males and females were 1.27(-0.94 to 3.47)and 0.93(-1.33 to 3.18),respectively.The AUC of SOS Z score in the diagnosis of low bone mass in males and females was 0.734(95%CI=0.380-0.788)and 0.679(95%CI=0.625-0.732),respectively.In males,the optimal cut-off of SOS Z score for low bone mass was -0.35,with the sensitivity,specificity,and correct diagnostic index of 64.1%,68.6%,and 0.327,respectively.In females,the optimal cut-off value of SOS Z scores for low bone mass was -1.14,with the sensitivity,specificity,and correct index of 73.9%,54.8%,and 0.285,respectively.Conclusion QUS and DXA show poor consistency in the diagnosis of BMD in the adults aged 18-40 years in Guangzhou,while QUS demonstrates an acceptable value in identifying low bone mass.

LRP5, Bone Mass Polymorphisms and Skeletal Disorders

The formation and maintenance of the gross structure and microarchitecture of the human skeleton require the concerted functioning of a plethora of morphogenic signaling processes. Through recent discoveries in the field of genetics, numerous genotypic variants have been implicated in pathologic skeletal phenotypes and disorders arising from the disturbance of one or more of these processes. For example, total loss-of-function variants of LRP5 were found to be the cause of osteoporosis-pseudoglioma syndrome (OPPG). LRP5 encodes for the low-density lipoprotein receptor-related protein 5, a co-receptor in the canonical WNT-β-catenin signaling pathway and a crucial protein involved in the formation and maintenance of homeostasis of the human skeleton. Beyond OPPG, other partial loss-of-function variants of LRP5 have been found to be associated with other low bone mass phenotypes and disorders, while LRP5 gain-of-function variants have been implicated in high bone mass phenotypes. This review introduces the roles that LRP5 plays in skeletal morphogenesis and discusses some of the structural consequences that result from abnormalities in LRP5. A greater understanding of how the LRP5 receptor functions in bone and other body tissues could provide insights into a variety of pathologies and their potential treatments, from osteoporosis and a variety of skeletal abnormalities to congenital disorders that can lead to lifelong disabilities.

Utility of Cone-Beam Computed Tomography in the Detection of Low Bone Mass-A Systematic Review

INTRODUCTION

Cone-beam computed tomography (CBCT) is widely used in the preoperative qualitative and quantitative assessment of dental implant sites, offering dimensional accuracy, spatial resolution, gray density, and contrast comparable to those of classical CT scan, yet with disputable ability to determine bone mass density.

MATERIALS AND METHODS

A systematic review of the literature was performed using the PubMed and SCOPUS databases, with terms referring to low bone mass and cone-beam computed tomography (CBCT).

RESULTS

Sixteen studies were included in the review. The results show different perspectives, but the evidence favors the use of CBCT, combined with dual-energy X-ray absorptiometry bone density scan (DXA) evaluation, for the assessment of the osteoporosis status of the aging population and, more specifically, in postmenopausal women. Radiographic density (RD) values of the dens and the left part of the first cervical vertebra show the strongest correlation coefficients and the highest sensitivity, specificity, and accuracy for predicting osteoporosis (OP) in the lumbar vertebrae and the femoral neck.

CONCLUSIONS

Our review suggests the potential of CBCT as a screening tool for patients with low bone mass using different radiomorphometric indices. Linear measurements of the inferior mandibular cortex were lower in osteoporotic individuals, indicating the perspective of CBCT also as a diagnostic tool for this disease.

The role of hypertension in bone mineral density among males older than 50 years and postmenopausal females: evidence from the US National Health and Nutrition Examination Survey, 2005-2010

Background

Hypertension is a significant chronic disease that has been linked with bone mineral density (BMD) in various studies. However, the conclusions are contradictory. The purpose of our study was to identify the bone mineral density (BMD) of postmenopausal females and males older than 50 years with hypertension.

Methods

This cross-sectional study of 4,306 participants from the 2005-2010 US National Health and Nutrition Examination Survey explored the relationship between BMD and hypertension. Participants who had a mean systolic blood pressure (SBP) ≥140 mmHg, or a mean diastolic blood pressure (DBP) ≥90 mmHg, or were taking any prescribed medicine for high blood pressure were defined as having hypertension. BMD values were measured at the femoral neck and lumbar vertebrae as the primary outcome. Weight general linear model was used to describe the status of BMD in patients with hypertension. Weighted multivariate regression analysis was conducted to demonstrate the association between hypertension and BMD. Weighted restricted cubic spline (RCS) was used to assess the relationship between BMD and SBP and DBP.

Results

Our study found that there was a positive association between hypertension and lumbar BMD and the lumbar BMD was significantly higher in the presence of hypertension than in the control group in both males (1.072 vs. 1.047 g/cm²) and females (0.967 vs. 0.938 g/cm²; both p < 0.05), but a similar pattern was not found in the femoral neck. Meanwhile, lumbar BMD was positively associated with SBP and negatively associated with DBP both in males and females. The prevalence of low bone mass and osteoporosis at the lumbar vertebrae was lower in male patients with hypertension than in the control group. However, no difference was observed among postmenopausal females between the hypertension and control groups.

Conclusions

Hypertension was associated with higher BMD at the lumbar vertebrae in both males older than 50 years and postmenopausal females.

Comparison of Physical Function among Elderly Japanese Women with and without Low Bone Mass and Low Muscle Mass: A Cross-Sectional Study of Older Women Who Engage in Regular Physical Activity

A decline in physical function is common among elderly people who have lost both bone and muscle mass. The aim of this study was to investigate the relationship between low bone and muscle mass and physical function in elderly women of different age groups who exercise regularly. The analysis included 299 elderly women. Low bone mass was determined by a T-score of −2.5 or less, and low muscle mass was determined by a skeletal muscle mass index of <5.7 kg/m2. Physical function was measured by grip strength, knee extension strength, standing ability, gait function, and balance function. The participants were divided into four groups based on bone and muscle mass (healthy, low bone mass, low muscle mass, and low bone and muscle mass groups), and their physical functions were compared. There were no statistically significant differences in physical function between the low bone and muscle mass and the healthy groups. There were also no statistically significant differences in physical function among the four groups in the late elderly stage (75 and older). Elderly women who exercise regularly are less likely to experience a decline in physical function, even if they have reduced bone and muscle mass.

Chronic Alcohol Consumption and its Impact on Bone and Metabolic Health - A Narrative Review

Chronic consumption of a large quantity of alcohol often results in the disruption of the communication between the nervous, endocrine and immune systems leading to profound and serious consequences at the physiological and behavioral levels. The overall impact of excessive alcohol consumption on bone health, metabolic profile and body composition, especially at moderate levels, is not well understood. Chronic excessive alcohol consumption adversely affects bone health through multiple mechanisms leading to low bone mass. It may also be significantly associated with various components on the metabolic syndrome. This review summarizes the findings from published studies that provide consistent evidence on the various effects of alcohol abuse on the bone health and metabolism.

Regulation of bone mass in endocrine diseases including diabetes

Hormonal regulation plays a key role in determining bone mass in humans. Both skeletal growth and bone loss in health and disease is critically controlled by endocrine factors and low bone mass is a feature of both excess and deficiency of a broad range of hormones. This article explores the impact of diabetes and thyroid, parathyroid, sex steroid and growth hormone disorders on bone mass and fracture risk. Evidence for current management strategies is provided along with suggested practice points and gaps in knowledge for future research.

Single Dose of SHR-1222, a Sclerostin Monoclonal Antibody, in Healthy Men and Postmenopausal Women With Low Bone Mass: A Randomized, Double-Blind, Placebo-Controlled, Dose-Escalation, Phase I Study

SHR-1222 is a humanized monoclonal antibody targeting sclerostin and has the potential to promote bone formation and reduce bone resorption. This study was aimed to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and immunogenicity of SHR-1222 in healthy men and postmenopausal women with low bone mass (BMD). It was a randomized, double-blind, placebo-controlled, dose-escalation, phase I study. Subjects received SHR-1222 at 50, 100, 200, 300, and 400 mg sequentially or matching placebo subcutaneously. Totally, 50 subjects with low BMD were enrolled and randomly assigned; 10 received placebo and 40 received SHR-1222 (50 mg, n = 4; 100, 200, 300, or 400 mg, n = 9). The most common adverse events that occurred at least 10% higher in subjects with SHR-1222 treatment than those with placebo were decreased blood calcium, blood urine present, increased blood cholesterol, electrocardiogram T wave abnormal, urinary tract infection, increased blood pressure diastolic, and positive bacterial test. All the above adverse events were mild in severity and well resolved except one of increased blood cholesterol in a subject lost to follow-up. The serum SHR-1222 concentration increased in a dose-dependent manner. Administration of SHR-1222 upregulated the bone-formation markers N-terminal propeptide of type 1 procollagen, osteocalcin, and bone-specific alkaline phosphatase, while downregulated the bone-resorption marker β-C-telopeptide. The BMD at the lumbar spine notably rose after a single dose of SHR-1222. The largest increase occurred in the 400 mg cohort (3.8, 6.7, and 6.1% on day 29, 57, and 85, respectively; compared with 1.4, 0.8, and 1.0% in the placebo group). Although 10.0% of subjects receiving SHR-1222 tested positive for anti–SHR-1222 antibodies, no obvious effects of antibody formation were found on pharmacokinetics. Overall, SHR-1222 was well tolerated at doses from 50 to 400 mg and is a promising new remedy for osteoporosis.

Clinical Trial Registration:http://www.clinicaltrials.gov, NCT03870100.

An Updated Reference for Calculating Bone Mineral Density T-Scores

CONTEXT

Bone mineral density (BMD) T-score references may be updated when the peak BMD of the population is unclear and warrants reevaluation.

OBJECTIVE

To update BMD T-score references using the peak BMD from the most recent National Health and Nutrition Examination Survey (NHANES) data.

METHODS

This cross-sectional study used NHANES data from 2005 to 2014. Non-Hispanic White females between the ages of 10 and 40 years (N = 1549) were our target population to estimate peak BMD (SD). Individuals aged ≥ 50 years (N = 5523) were used to compare the percentages of osteoporosis and low bone mass based on existing and updated BMD T-score references. BMD data within the age at attainment of peak BMD ± 5 years were used to calculate updated BMD T-score references.

RESULTS

The updated average of BMD (SD) for diagnosing osteoporosis at the femoral neck and lumbar spine were 0.888 g/cm2 (0.121 g/cm2) and 1.065 g/cm2 (0.122 g/cm2), respectively. The percentages of individuals with osteoporosis at the femoral neck and low bone mass at the femoral neck and lumbar spine based on the updated BMD T-score references were higher than the percentages of people designated with these outcomes under the existing guidelines (P < 0.001). However, we observed the opposite pattern for lumbar spine osteoporosis (P < 0.001).

CONCLUSIONS

We calculated new BMD T-score references at the femoral neck and lumbar spine. We found significant differences in the percentages of individuals classified as having osteoporosis and low bone mass between the updated and existing BMD T-score references.

A pilot screening study for low bone mass in Singaporean women using years since menopause and BMI

OBJECTIVE

Current risk assessment tools for osteoporosis have inconsistent performance across different cohorts, making them difficult for clinical practice. This study aimed to evaluate a simple screening index comprising years since menopause (YSM) and body mass index (BMI) that identifies postmenopausal Singaporean women with a greater likelihood of low bone mass.

METHODS

The study used data from 188 treatment-naïve postmenopausal women. The associations between low bone mass and different demographic variables, including age, YSM and BMI, were assessed using multivariable logistic regression. Diagnostic performance of the calculated screening index was compared to the Osteoporosis Self-Assessment Tool for Asians (OSTA) and the Fracture Risk Assessment Tool (FRAX^®).

RESULTS

YSM and BMI were significantly associated with low bone mass. The area under the receiver operating characteristic curves was 0.803 for the screening index, 0.759 for the OSTA, 0.683 for the FRAX^® (major osteoporotic fracture probability [MOFP]) and 0.647 for the FRAX^® (hip fracture probability [HFP]). Non-parametric Spearman's correlation between the screening index and the other models was 0.857 with the OSTA score, 0.694 with the FRAX^® (HFP) and 0.565 with the FRAX^® (MOFP) (p < 0.0005).

CONCLUSIONS

The diagnostic performance of the screening index comprising YSM and BMI was equivalent to the OSTA and the FRAX^®. A risk chart was developed for clinicians to identify and recommend subjects for a further dual-energy X-ray absorptiometry scan. Validation of this model in larger and more diverse cohorts is required.

Deep Learning With Electronic Health Records for Short-Term Fracture Risk Identification: Crystal Bone Algorithm Development and Validation

Background

Fractures as a result of osteoporosis and low bone mass are common and give rise to significant clinical, personal, and economic burden. Even after a fracture occurs, high fracture risk remains widely underdiagnosed and undertreated. Common fracture risk assessment tools utilize a subset of clinical risk factors for prediction, and often require manual data entry. Furthermore, these tools predict risk over the long term and do not explicitly provide short-term risk estimates necessary to identify patients likely to experience a fracture in the next 1-2 years.

Objective

The goal of this study was to develop and evaluate an algorithm for the identification of patients at risk of fracture in a subsequent 1- to 2-year period. In order to address the aforementioned limitations of current prediction tools, this approach focused on a short-term timeframe, automated data entry, and the use of longitudinal data to inform the predictions.

Methods

Using retrospective electronic health record data from over 1,000,000 patients, we developed Crystal Bone, an algorithm that applies machine learning techniques from natural language processing to the temporal nature of patient histories to generate short-term fracture risk predictions. Similar to how language models predict the next word in a given sentence or the topic of a document, Crystal Bone predicts whether a patient’s future trajectory might contain a fracture event, or whether the signature of the patient’s journey is similar to that of a typical future fracture patient. A holdout set with 192,590 patients was used to validate accuracy. Experimental baseline models and human-level performance were used for comparison.

Results

The model accurately predicted 1- to 2-year fracture risk for patients aged over 50 years (area under the receiver operating characteristics curve [AUROC] 0.81). These algorithms outperformed the experimental baselines (AUROC 0.67) and showed meaningful improvements when compared to retrospective approximation of human-level performance by correctly identifying 9649 of 13,765 (70%) at-risk patients who did not receive any preventative bone-health-related medical interventions from their physicians.

Conclusions

These findings indicate that it is possible to use a patient’s unique medical history as it changes over time to predict the risk of short-term fracture. Validating and applying such a tool within the health care system could enable automated and widespread prediction of this risk and may help with identification of patients at very high risk of fracture.

Clinical, Endocrine, Metabolic Profile, and Bone Health in Sheehan's Syndrome

BACKGROUND

Sheehan's syndrome (SS) occurs due to ischemic pituitary necrosis resulting from severe postpartum hemorrhage (PPH). SS is characterized by varying degrees of pituitary insufficiency involving mostly the anterior lobe. Comprehensive data on SS apart from endocrine dysfunction is scarcely available.

MATERIALS AND METHODS

Thirty-eight subjects previously diagnosed with SS were enrolled in this observational study. Their clinical, biochemical, hormonal, radiological data at presentation were recorded from past records and bone density was measured in all.

RESULTS

Mean (±SD) age was 39 (±8.7) years and diagnostic delay was 9.3 (±5.5) years. All had history of PPH and lactation failure. About 47% were referred from emergency, and rest 53% were diagnosed from outpatient's department. Mean free T4, TSH, prolactin, morning cortisol, FSH, LH, and IGF-1 were mostly low. Panhypopituitarism was present in 97%. Hyponatremia was most common electrolyte imbalance found in about 53%. More than 40% had elevated transaminases. Dyslipidemia especially low HDL was found in 31 (81.5%) subjects. MRI of hypothalamus-pituitary region showed empty sella in 53% and partial empty sella in 47%. About 13% subjects had diabetes mellitus. Low bone mass (BMD Z-Score ≤-1) was seen in 80% and it was more severe (BMD Z-Score ≤-2) in 44% subjects, affecting predominantly lumbar spine. Bone loss at femoral neck was less prominent.

CONCLUSION

Apart from variable spectrum of clinical presentation, subjects with SS have significant abnormalities in serum electrolytes, metabolic parameters. Low bone mass is also a frequent accompaniment.

A Primary Care Provider's Guide to Bone Health in Spinal Cord-Related Paralysis

Individuals with spinal cord injury/disorder (SCI/D) are at high risk for developing secondary osteoporosis. Bone loss after neurologic injury is multifactorial and is dependent on the time from and extent of neurologic injury. Most bone loss occurs in the first year after complete motor paralysis, and fractures occur most commonly in the distal femur and proximal tibia (paraplegic fracture). The 2019 International Society for Clinical Densitometry Position Statement in SCI establishes that dual-energy X-ray absorptiometry (DXA) can be used to both diagnose osteoporosis and predict lower extremity fracture risk in individuals with SCI/D. Pharmacologic treatments used in primary osteoporosis have mixed results when used for SCI/D-related osteoporosis. Ambulation, standing, and electrical stimulation may be helpful at increasing bone mineral density (BMD) in individuals with SCI/D but do not necessarily correlate with fracture risk reduction. Clinicians caring for individuals with spinal cord-related paralysis must maintain a high index of suspicion for fragility fractures and consider referral for surgical evaluation and management.

Diabetes mellitus is a risk factor for low bone mass-related fractures: A meta-analysis of cohort studies

BACKGROUND

Diabetes mellitus (DM) is inconsistently associated with the risk of low bone mass-related fractures (LBMF). This study aimed to summarize available cohort studies regarding the strength of association between type 2 diabetes mellitus (T2DM) and LBMF.

METHODS

Electronic searches of PubMed, Embase, and the Cochrane Library were performed to identify studies through April 2016. Cohort studies that reported effect estimates with 95% confidence intervals (CIs) of LBMF for T2DM and control comparison were included.

RESULTS

The summary relative risks (RRs) for T2DM versus non-T2DM were associated with a higher risk of LBMF (RR: 1.24; 95% CI: 1.09-1.41; P = .001). Further, women with T2DM showed a harmful impact on the incidence of LBMF (RR: 1.19; 95% CI: 1.04-1.36; P = .010). However, in men, T2DM showed no significant impact on the risk of LBMF (RR: 1.14; 95% CI: 0.93-1.39; P = .215). Furthermore, the summary results suggested an association between T2DM and LBMF in studies that reported hazard ratio (HR) as an effect estimate in total cohorts (HR: 1.31; 95% CI: 1.17-1.46; P < .001), men (HR: 1.26; 95% CI: 1.11-1.43; P < .001), and women (HR: 1.32; 95% CI: 1.16-1.50; P < .001). However, these significant associations were not observed in studies that reported RR/odds ratio as an effect estimate.

CONCLUSIONS

The present meta-analysis confirmed that T2DM was associated with an increased prevalence of LBMF compared with non-T2DM.

Effect of Calcium Derived from Lithothamnion sp. on Markers of Calcium Metabolism in Premenopausal Women

A double-blind crossover pilot trial tested the hypothesis that botanically derived calcium could demonstrate greater influence over calcium metabolism markers compared with a nonplant-derived calcium carbonate supplement or placebo. Twelve fasting female subjects received a single oral dose of Aquamin F™ (derived from the marine algal Lithothamnion sp.), or calcium carbonate, or placebo. Blood and urine samples were collected at baseline and over 12 h to evaluate ionized and total calcium and parathyroid hormone (PTH). Subjects treated with Aquamin F demonstrated significantly greater urinary clearance of calcium after 12 h compared with placebo (P = .004). Following a meal at 90 min, subjects treated with Aquamin F demonstrated a more prolonged suppression of serum PTH concentration (significantly lower than placebo at 90, 120, and 240 min). Calcium carbonate provided an intermediate response; urinary clearance was not significantly different from placebo treatment and PTH was only significantly lower than placebo at 90 min. Aquamin F may demonstrate greater influence over these markers of calcium metabolism than calcium carbonate or placebo, as suggested by a greater calciuric response and a more prolonged suppression of serum PTH concentrations following a meal in premenopausal women.

Effects of Omega-3 Polyunsaturated Fatty Acid Supplementation on Bone Turnover in Older Women

Animal and human studies indicate that omega (n)-3 polyunsaturated fatty acids (PUFA) can influence bone health. We conducted a randomized, double-blind, placebo-controlled trial of the effects of n-3 long chain (LC) PUFA supplementation (N-3 LCPUFA) on red blood cell (RBC) fatty acid levels and bone turnover markers in older postmenopausal women. One hundred and twenty-six postmenopausal women (mean age 75±7 years) were treated with n-3 LCPUFA (1.2 g eicosapentaenoic acid [EPA]/docosahexaenoic acid [DHA]/day, n=85) or placebo (olive oil, n=41) for 6 months. All women received 315 mg calcium citrate and 1000 IU cholecalciferol. RBC DHA (weight %) increased in the n-3 LCPUFA group, compared to no change in the placebo group (P<0.001). The ratio of DHA+EPA:arachidonic acid (AA) increased by 42 % in the n-3 LCPUFA group and by 5% in the placebo group (P<0.001). Bone-specific alkaline phosphatase and osteocalcin decreased in the n-3 LCPUFA group (P<0.05) with no between-group difference. Short-term n-3 LCPUFA supplementation increased RBC concentrations of DHA and n-3:n-6 ratios. Bone turnover decreased with n-3 LCPUF, but not statistically compared to placebo. The results point to the need for investigations with greater dosages of n-3 LCPUFA for a longer duration to understand the contribution to bone metabolism in postmenopausal women.

A de novo 1.58 Mb deletion, including MAP2K6 and mapping 1.28 Mb upstream to SOX9, identified in a patient with Pierre Robin sequence and osteopenia with multiple fractures

Defects of long-range regulatory elements of dosage-sensitive genes represent an under-recognized mechanism underlying genetic diseases. Haploinsufficiency of SOX9, the gene essential for development of testes and differentiation of chondrocytes, results in campomelic dysplasia, a skeletal malformation syndrome often associated with sex reversal. Chromosomal rearrangements with breakpoints mapping up to 1.6 Mb up- and downstream to SOX9, and disrupting its distant cis-regulatory elements, have been described in patients with milder forms of campomelic dysplasia, Pierre Robin sequence, and sex reversal. We present an ∼1.58 Mb deletion mapping ∼1.28 Mb upstream to SOX9 that encompasses its putative long-range cis-regulatory element(s) and MAP2K6 in a patient with Pierre Robin sequence and osteopenia with multiple fractures. Low bone mass panel testing using massively parallel sequencing of 23 nuclear genes, including COL1A1 and COL1A2 was negative. Based on the previous mouse model of Map2k6, suggesting that Sox9 is likely a downstream target of the p38 MAPK pathway, and our previous chromosome conformation capture-on-chip (4C) data showing potential interactions between SOX9 promoter and MAP2K6, we hypothesize that deletion of MAP2K6 might have affected SOX9 expression and contributed to our patient's phenotype.

Serum bicarbonate and bone mineral density in US adults

BACKGROUND

Chronic metabolic acidosis leads to bone mineral loss and results in lower bone mineral density (BMD), which is a risk factor for osteoporosis-related fractures. The effect of low-level metabolic acidosis on bone density in the general population is unknown.

STUDY DESIGN

Cross-sectional study.

SETTING & PARTICIPANTS

9,724 nationally representative adults 20 years or older in NHANES (National Health and Nutrition Examination Survey) 1999-2004.

FACTOR

Serum bicarbonate level.

OUTCOMES

Lumbar and total BMD, as well as low lumbar and total bone mass, defined as 1.0 SD below the sex-specific mean value of young adults.

MEASUREMENTS

BMD was measured by dual-energy x-ray absorptiometry and serum bicarbonate was measured in all participants.

RESULTS

Both men and women with lower serum bicarbonate levels were more likely to be current smokers and had higher body mass index and estimated net endogenous acid production. There was a significant linear trend across quartiles of serum bicarbonate with lumbar BMD in the total population, as well as in sex-specific models (P=0.02 for all 3 models, P=0.1 for interaction). For total BMD, a significant association was seen with serum bicarbonate level for women but not men (P=0.02 and P=0.1, respectively; P=0.8 for interaction), and a significant association was seen for postmenopausal women but not premenopausal women (P=0.02 and P=0.2, respectively; P=0.5 for interaction). Compared with women with serum bicarbonate levels <24mEq/L, those with serum bicarbonate levels ≥27mEq/L had 0.018-g/cm(2) higher total BMD (95% CI, 0.004-0.032; P=0.01) and 31% lower odds of having low total bone mass (OR, 0.68; 95% CI, 0.46-0.99; P=0.049).

LIMITATIONS

Cross-sectional study using a single measurement of serum bicarbonate. Subgroup differences are not definitive.

CONCLUSIONS

Lower serum bicarbonate levels are associated with lower BMD in US adults. Further studies should examine whether serum bicarbonate levels should be incorporated into the diagnostic assessment and management of osteoporosis.

Bone mineral density, thyroid function, and gonadal status in young adult survivors of childhood cancer

Introduction

During the last years, changes in the diagnosis and treatment have caused a significant increase of the number of young adults who experienced cancer in childhood. This enlarging population is affected by many health problems, including multiple hormone deficiencies and bone mineral deficits. This is the first polish study assessing bone mineral density and endocrine status in young adult cancer survivors.

Material and methods

A total of 76 long-term survivors treated for pediatric cancer were identified. The mean age at the time of study was 24.1 ±3.5 years. Bone mineral density and TSH, fT3, fT4, FSH, LH, estradiol and testosterone level were assessed for each patient.

Results

Nine subjects were diagnosed with subclinical hypothyroidism. We found higher level of TSH in the study group, in comparison with control group (p = 0.015). Eighteen patients had increased level of FSH. In the study group higher number of patients with high FSH level was found in comparison with the control group (p = 0.049). A low BMD was observed in 7 patients whereas mild BMD deficits were found in 19 participants.

Conclusions

In conclusion, our data show that young adult cancer survivors might experienced various hormonal problems including low bone mass, thyroid impairment and gonadal dysfunction. Some of the patients required treatment, but they were not diagnosed before this study. There is the lack of proper clinical assessment among adult childhood cancer survivors in Poland. Therefore, we demonstrated the need for a comprehensive plan for longitudinal follow-up for late effects in these population.

Cost-minimization study comparing annual infusion of zoledronic acid or weekly oral alendronate in women with low bone mineral density

Cost-minimization study to assess the annual direct costs of 2 antiresorptive strategies in postmenopausal women with low bone mineral densities (BMDs). Patients were randomly assigned to receive 70 mg of oral weekly alendronate or a 1-time 5mg of intravenous zoledronic acid. All medical and nonmedical direct costs were recorded for 1 yr. Student's t-test or the Chi-squared test was used. A total of 101 postmenopausal women were enrolled with a mean age of 58.3 ± 7.6 yr and a postmenopausal period of 13.5 ± 8.3 yr. A total of 50 patients completed 1 yr of alendronate and 51 patients received zoledronic acid. At baseline, no differences were seen between the 2 groups in anthropometric measures, comorbidities, and bone mineral density. The costs for medical attention for low bone mass were $81,532 (US Dollars) for the alendronate group and $69,251 for the zoledronic acid group; the cost per patient was $1631 in the alendronate group vs $1358 in the zoledronic acid group (p<0.0001). Therefore, zoledronic acid treatment provided an annual savings of 15% of the direct costs compared with oral alendronate treatment. Moreover, there was a significant increase in lumbar spine T-scores in the zoledronic acid group when compared with the alendronate group. Annual zoledronic acid infusion as an antiresorptive treatment in women with low BMD provides significant monetary savings when compared with weekly alendronate therapy for 1 yr. Zoledronic acid infusion is also linked to higher increase in BMD and compliance.

Coronary microvascular endothelial dysfunction is an independent predictor of development of osteoporosis in postmenopausal women

BACKGROUND

A growing body of evidence links coronary artery atherosclerosis and calcification to osteoporosis in women. The endothelium plays a critical role in maintaining vascular integrity and may play a role in bone metabolism. We aimed to determine whether early coronary atherosclerosis, as detected by coronary microvascular endothelial dysfunction (CMED), predicts the development of osteoporosis in postmenopausal women.

METHODS

Coronary vascular reactivity was evaluated in 194 postmenopausal women greater than 50 years of age and with non-obstructive coronary arteries by administration of intracoronary acetylcholine during diagnostic angiography. CMED was defined as ≤50% increase in coronary blood flow from baseline in response to maximal dose. After a median follow-up of 7.0±0.3 years, patients were assessed by a questionnaire for development of osteoporosis.

RESULTS

The average age of the cohort was 60.9±7.4 years. Women with CMED were twice as likely to develop osteoporosis compared with women without endothelial dysfunction after adjustment for potential confounders (relative risk, 2.4; 95% confidence interval [CI], 1.1, 5.6, P=0.02). Epicardial endothelial dysfunction was not associated with development of osteoporosis.

DISCUSSION

Early coronary atherosclerosis with endothelial dysfunction is an independent marker for increased risk of developing osteoporosis in postmenopausal women greater than 50 years of age without obstructive coronary artery disease. The current study supports a link between coronary atherosclerosis and osteoporosis.

Intake of dehydrated nopal (Opuntia ficus indica) improves bone mineral density and calciuria in adult Mexican women

Background

The intake of dehydrated nopal (DN) at a high stage of maturity along with high calcium content could improve bone mineral density (BMD) and calciuria and thus prevent osteoporosis.

Objective

To evaluate the effect of calcium intake from a vegetable source (DN) on BMD and calciuria covering a 2-year period in menopausal and non-menopausal women with low bone mass (LBM).

Methods

The study was quasi-experimental, blinded, and randomized, and included 131 Mexican women aged 35–55. Urinary calcium/creatinine index (CCI) was determined; BMD was analyzed on lumbar spine and total hip regions. Four groups were studied: Control group (CG), women with normocalciuria and a minimum dose of DN; experimental group 1 (EG1), women with hypercalciuria and a minimum dose of DN; experimental group 2 (EG2), women with hypercalciuria, and a maximum dose of DN; and normal group (NG) for reference in BMD.

Results

After the first semester of treatment, calciuria levels in women from both experimental groups returned to normal, remaining constant for the rest of the treatment. The percentage difference in BMD increased in the total hip region in the CG (pre 4.5% and post 2.1%) and EG2 (pre 1.8% and post 2.5%) groups significantly in comparison to NG and EG1, which exhibited a significant decrease in their BMD. BMD increased only for the lumbar region in the EG2 group (premenopausal).

Conclusion

The use of a vegetable calcium source such as nopal improves BMD in women with LBM in the total hip and lumbar spine regions principally in the premenopausal women, maintaining constant and normal calciuria levels.

Bone density assessment in patients with mucopolysaccharidosis: A preliminary report from patients with MPS II and VI

Enzyme replacement therapy has been successful in alleviating morbidity and improving endurance in Mucopolysaccharidosis (MPS) type I, II, and VI, however little attention has been paid to the effects on bone mineralization. Brief case reports in MPS type III and IV suggest that bone mineral density (BMD) is diminished, but did not account for patient size. In this report, BMD was evaluated by quantitative computed tomography and by dual-energy x-ray absorptiometry (DXA) in separate studies involving 10 patients with MPS type VI (7 Female; 7.0 to 21.0 y) and 4 male patients with MPS II (8.1 to 35.5 y). Vitamin D intake met the current RDA (200 IU) for most, though 25-OH vitamin D was insufficient (< 30 ng/mL) in 87.5% of patients tested. Ht Z-score was low -5.8 +/- 3.6, with height deficits greatest in MPS VI. Spine and whole body BMD Z-scores by DXA were considered normal for chronological age in all MPS II, and after correction for Ht Z-score, in all but one subject with MPS VI. These results suggest that vitamin D insufficiency is quite common in MPS. BMD by DXA is within normal range for most, particularly after correction for short stature. A review of bone health assessment is provided as well as a discussion of these results.

Prevalence of fractures among the Thalassemia syndromes in North America

Historically, fractures are cited as a frequent problem in patients with Thalassemia prior to optimization of transfusion and chelation regimens. The aim of this study was to determine the prevalence of fractures in a contemporary sample of North American patients with Thalassemia. The North American Thalassemia Clinical Research Network (TCRN) database registry was used to gather historical data on 702 patients with common alpha and beta-Thalassemia diagnoses including Thalassemia Major (TM), Intermedia (TI), E/Beta, homozygous alpha Thalassemia (AT), Hemoglobin H disease (HbH) and HbH with Constant Spring (HbH/CS), who consented to a medical record chart review. Bone mineral density (BMD) measurements by DXA were available for review in a subgroup of patients (n = 312). The overall fracture prevalence among all Thalassemia syndromes was 12.1%, equally distributed between females (11.5%) and males (12.7%). Fractures occurred more frequently in TM (16.6%) and TI (12.2%) compared to E/Beta (7.4%) and alpha (2.3%). Prevalence increased with age (2.5% ages 0-10 years, 7.4% ages 11-19 years, 23.2% ages >20 years) and with use of sex hormone replacement therapy (SHRT) (P < 0.01). On average, BMD Z and T scores were 0.85 SD lower among patients with a history of fractures (mean Z/T score -2.78 vs. -1.93, 95% CI for the difference -0.49 to -1.22 SD, P = 0.02). Presence of other endocrinopathies (i.e. hypothyroidism, hypoparathyroidism and diabetes mellitus), anthropometric parameters, heart disease or hepatitis C were not significant independent predictors of fractures. These data indicate that fractures remain a frequent complication among the aging patients with both TM and TI beta-Thalassemia. However, the fracture prevalence has improved compared to published reports from the 1960s to 1970s. In addition, children with Thalassemia appear to have low fracture rates compared to the general population.