Association of Immune Cell Subsets with Incident Hip Fracture: The Cardiovascular Health Study

In this study, we aimed to evaluate the association of innate and adaptive immune cell subsets in peripheral blood mononuclear cells (PBMCs) with hip fracture. To conduct this study, we used data from the Cardiovascular Health Study (CHS), a U.S. multicenter observational cohort of community-dwelling men and women aged ≥ 65 years. Twenty-five immune cell phenotypes were measured by flow cytometry from cryopreserved PBMCs of CHS participants collected in 1998-1999. The natural killer (NK), γδ T, T helper 17 (Th17), and differentiated/senescent CD4+CD28- T cell subsets were pre-specified as primary subsets of interest. Hip fracture incidence was assessed prospectively by review of hospitalization records. Multivariable Cox hazard models evaluated associations of immune cell phenotypes with incident hip fracture in sex-stratified and combined analyses. Among 1928 persons, 259 hip fractures occurred over a median 9.7 years of follow-up. In women, NK cells were inversely associated with hip fracture [hazard ratio (HR) 0.77, 95% confidence interval (CI) 0.60-0.99 per one standard deviation higher value] and Th17 cells were positively associated with hip fracture [HR 1.18, 95% CI 1.01-1.39]. In men, γδ T cells were inversely associated with hip fracture [HR 0.60, 95% CI 0.37-0.98]. None of the measured immune cell phenotypes were significantly associated with hip fracture incidence in combined analyses. In this large prospective cohort of older adults, potentially important sex differences in the associations of immune cell phenotypes and hip fracture were identified. However, immune cell phenotypes had no association with hip fracture in analyses combining men and women.

Sex and Racial Differences in Systemic Lupus Erythematosus Among US Adults in the All of Us Research Program

OBJECTIVE

Men with systemic lupus erythematosus (SLE) are an understudied population. The present study characterized differences between men and women with SLE.

METHODS

We examined cross-sectionally participants with SLE in the All of Us Research Program, a US cohort with a participant survey at enrollment (May 2018 to June 2022) and linked electronic health record (EHR) data. We described and compared characteristics of men and women with SLE encompassing disease manifestations and prescribed medications from EHR data and socioeconomic factors, including health literacy and health care access and utilization, from surveys. We reported racial variations stratified by sex.

RESULTS

Of 1,462 participants with SLE, 126 (9%) were male. Men reported lower educational attainment and less fatigue than women. Myocardial infarction was significantly more common in men. Men had significantly less confidence in completing medical forms than women and exhibited a trend toward requiring more help in reading health-related materials. Barriers to health care access and utilization were common in both men and women (40% versus 47%, respectively, reporting some reason for delay in care; P = 0.35). Women of race other than Black or African American or White more often reported delaying care due to cultural differences between patient and provider.

CONCLUSION

Our study demonstrated major clinical and health literacy differences in men and women with SLE. Socioeconomic factors were significant barriers to health care in both sexes. Our study suggests men have disproportionately poorer health literacy, which may exacerbate preexisting disparities. Further large prospective studies, focusing on recruiting men, are needed to better characterize racial differences in men with SLE.

Mortality Following Hip Fracture in Older Adults With and Without Coronary Heart Disease

BACKGROUND

Comorbidities like coronary heart disease are common among older people who sustain an osteoporotic hip fracture. However, their impact on short- and long-term mortality post-hip fracture is not well quantified.

METHODS

We examined 4092 and 1173 older adults without and with prevalent coronary heart disease, respectively. Post-hip fracture mortality rates were computed with Poisson models and hazard ratios with Cox regression. For perspective, we compared mortality rates among participants with prevalent coronary heart disease who had either a hip fracture or incident heart failure (but no hip fracture).

RESULTS

Among participants without prevalent coronary heart disease, the mortality rate post-hip fracture was 21.83 per 100 participant years, including 49.27 per 100 participant years in the first 6 months following hip fracture. Among participants with prevalent coronary heart disease, the corresponding mortality rates were 32.52 and 79.44 per 100 participant years, respectively. Participants with prevalent coronary heart disease and incident heart failure (but no hip fracture) had corresponding post-incident heart failure mortality rates per 100 participant years of 25.62 overall and 46.4 in the first 6 months. In all 3 groups, the hazard ratio for mortality was similarly elevated: 5- to 7-fold at 6 months and 1.7- to 2.5-fold beyond 5 years.

CONCLUSION

As a case study in the absolute effects of a comorbidity on post-hip fracture mortality, hip fracture in a person with coronary heart disease carries an exceedingly high mortality rate, even higher than that following incident heart failure in individuals with coronary heart disease.

The Pathophysiology, Identification and Management of Fracture Risk, Sublesional Osteoporosis and Fracture among Adults with Spinal Cord Injury

BACKGROUND

The prevention of lower extremity fractures and fracture-related morbidity and mortality is a critical component of health services for adults living with chronic spinal cord injury (SCI).

METHODS

Established best practices and guideline recommendations are articulated in recent international consensus documents from the International Society of Clinical Densitometry, the Paralyzed Veterans of America Consortium for Spinal Cord Medicine and the Orthopedic Trauma Association.

RESULTS

This review is a synthesis of the aforementioned consensus documents, which highlight the pathophysiology of lower extremity bone mineral density (BMD) decline after acute SCI. The role and actions treating clinicians should take to screen, diagnose and initiate the appropriate treatment of established low bone mass/osteoporosis of the hip, distal femur or proximal tibia regions associated with moderate or high fracture risk or diagnose and manage a lower extremity fracture among adults with chronic SCI are articulated. Guidance regarding the prescription of dietary calcium, vitamin D supplements, rehabilitation interventions (passive standing, functional electrical stimulation (FES) or neuromuscular electrical stimulation (NMES)) to modify bone mass and/or anti-resorptive drug therapy (Alendronate, Denosumab, or Zoledronic Acid) is provided. In the event of lower extremity fracture, the need for timely orthopedic consultation for fracture diagnosis and interprofessional care following definitive fracture management to prevent health complications (venous thromboembolism, pressure injury, and autonomic dysreflexia) and rehabilitation interventions to return the individual to his/her pre-fracture functional abilities is emphasized.

CONCLUSIONS

Interprofessional care teams should use recent consensus publications to drive sustained practice change to mitigate fracture incidence and fracture-related morbidity and mortality among adults with chronic SCI.

Association of covert brain infarcts and white matter hyperintensities with risk of hip fracture in older adults: the Cardiovascular Health Study

Covert brain infarcts and white matter hyperintensities (WMHs), incidental markers of brain microvascular disease commonly seen on brain MRIs in older adults, have been associated with falls and lower bone mineral density. We found covert infarcts and WMHs may also be associated with an increased risk of future hip fracture.

INTRODUCTION

To determine whether covert infarcts and white matter hyperintensities (WMHs) are associated with increased risk of incident hip fracture.

METHODS

A prospective cohort of 3373 community-dwelling adults aged ≥ 65 years enrolled in the Cardiovascular Health Study with a brain MRI (1992-1993) was analyzed. Covert infarcts were categorized by number of infarcts and largest infarct size. WMH burden was assessed by radiologists and graded qualitatively from 0 (no WMHs) to 9 (extensive).

RESULTS

Participants had 465 incident hip fractures during a mean follow-up of 12.8 years. The demographic-adjusted hazard of incident hip fracture was 32% higher among participants with ≥ 1 covert infarct compared to those without infarcts (hazard ratio (HR) 1.32; 95% CI, 1.08-1.62). The hazard of incident hip fracture was similar after further adjustment for medications and medical history (HR = 1.34; 95% CI, 1.08-1.65), but attenuated following additional adjustment for functional status, frailty, and falls (HR = 1.25; 95% CI, 0.99-1.57). Fully adjusted hazard of incident hip fracture per increase in infarct number was 1.10 (95% CI, 0.98-1.23); risk in individuals whose largest infarct was ≥ 20 mm versus 3 to < 20 mm was similar. Compared with WMH grades 0-1, the demographic-adjusted hazard of hip fracture was 1.34 (95% CI, 1.09-1.66) and 1.83 (95% CI, 1.37-2.46), respectively, for WMH grades 2-3 and 4-9. The hazard was similar following adjustment for medications and medical history (grades 2-3: HR = 1.32; 95% CI, 1.05-1.64; grades 4-9: HR = 1.69; 95% CI, 1.23-2.30), but attenuated following additional adjustment for functional status, frailty, and falls (grades 2-3: HR = 1.24; 95% CI, 0.98-1.56; grades 4-9: HR = 1.34; 95% CI, 0.95-1.90).

CONCLUSION

Older, community-dwelling adults with covert infarcts or WMHs may be at increased risk of hip fracture.

Lower extremity fracture prevention and management in persons with spinal cord injuries and disorders: The patient perspective

CONTEXT/OBJECTIVE

To describe patient experiences with fracture prevention and management among persons with spinal cord injuries/disorders (SCI/D).

DESIGN

Qualitative data collected via semi-structured telephone interviews.

SETTING

Veterans Health Administration (VA) SCI/D System of Care.

PARTICIPANTS

Veterans with SCI/D (n = 32) who had experienced at least one lower-extremity fracture in the prior 18 months.

INTERVENTIONS

N/A.

OUTCOME MEASURES

Interview questions addressed patients': pre-fracture knowledge of osteoporosis and bone health, diagnosis and management of osteoporosis, history and experiences with fracture treatment, and post-fracture care and experiences.

RESULTS

Participants expressed concerns about bone health and fractures in particular, which for some, limited activities and participation. Participants recalled receiving little information from providers about bone health or osteoporosis and described little knowledge about osteoporosis prevention prior to their fracture. Few participants reported medication management for osteoporosis, however many reported receiving radiographs/scans to confirm a fracture and most reported being managed non-operatively. Some reported preference for surgical treatment and believed their outcomes would have been better had their fracture been managed differently. Many reported not feeling fully included in treatment decision-making. Some described decreased function, independence and/or participation post-fracture.

CONCLUSION(S)

Our results indicate that persons with SCI/D report lacking substantive knowledge about bone health and/or fracture prevention, and following fracture, feel unable and/or hesitant to resume pre-fracture participation. In addition, our findings indicate that individuals with SCI/D may not feel as engaged as they would like to be in establishing fracture treatment plans. As such, persons with SCI/D may benefit from ongoing discussions with providers about risks and benefits of fracture treatment options and consideration of subsequent function and participation, to ensure patients preferences are considered.

The Association of Lipids and Lipoproteins with Hip Fracture Risk: The Cardiovascular Health Study

BACKGROUND

It is uncertain if lipids or lipoproteins are associated with osteoporotic fractures. In this study, incident hip fracture risk according to conventional lipid levels and lipoprotein levels and sizes was examined.

METHODS

We followed 5832 participants aged ≥65 years from the Cardiovascular Health Study for hip fracture for a mean of 13.5 (SD 5.7) years. Standard enzymatic methods were used to determine lipid levels (ie, high-density lipoprotein-cholesterol [HDL-c], low-density lipoprotein-cholesterol [LDL-c], and triglycerides). Nuclear magnetic resonance spectroscopy was used to measure lipoprotein fractions (ie, very-low-density lipoprotein-particle [VLDL-P], low-density lipoprotein-particle [LDL-P], high-density lipoprotein-particle [HDL-P]) in a subset of 1849 participants.

RESULTS

We documented 755 incident hip fractures among women (1.19 fractures per 100 participant years [95% confidence interval, 1.04, 1.35]) and 197 among men (0.67 fractures per 100 participant years [95% CI, 0.41, 1.10]) over an average follow-up. HDL-c and LDL-c levels had statistically significant nonlinear U-shaped relationships with hip fracture risk (HDL-c, P = .009; LDL-c, P = .02). Triglyceride levels were not significantly associated with hip fracture risk. In fully adjusted conjoint models, higher VLDL-P concentration (hazard ratio [HR] per 1 standard deviation [SD] increment 1.47 [1.13, 1.91] and size [HR per 1 SD increment 1.24 [1.05, 1.46]) and higher high-density lipoprotein particle size (HR per 1 SD increment 1.81 [1.25, 2.62]) were all associated with higher hip fracture risk.

CONCLUSIONS

Lipids and lipoproteins are associated with hip fracture risk in older adults. The associations are complex. Mechanistic studies are needed to understand these findings.

Trimethylamine N-oxide and hip fracture and bone mineral density in older adults: The cardiovascular health study

CONTEXT

Gut microbiota-derived metabolite trimethylamine N-oxide (TMAO) may adversely affect bone by inducing oxidative stress. Whether this translates into increased fracture risk in older adults is uncertain.

OBJECTIVE

Determine the associations of plasma TMAO with hip fracture and bone mineral density (BMD) in older adults.

DESIGN AND SETTING

Cox hazard models and linear regression stratified by sex examined the associations of TMAO with hip fracture and BMD in the longitudinal cohort of the Cardiovascular Health Study.

PARTICIPANTS

5019 U.S. adults aged ≥65 years.

EXPOSURE

Plasma TMAO.

MAIN OUTCOME MEASURES

Incident hip fractures; total hip BMD dual x-ray absorptiometry in a subset (n = 1400).

RESULTS

Six hundred sixty-six incident hip fractures occurred during up to 26 years of follow-up (67,574 person-years). After multivariable adjustment, TMAO was not significantly associated with hip fracture (women: hazard ratio (HR) [95% confidence interval (CI)] of 1.00[0.92,1.09] per TMAO doubling; men: 1.12[0.95,1.33]). TMAO was also not associated with total hip BMD (women: BMD difference [95% CI] of 0.42 g/cm2*100 [-0.34,1.17] per TMAO doubling; men: 0.19[-1.04,1.42]). In exploratory analyses, we found an interaction between body mass index (BMI) and the association of TMAO with hip fracture (P < 0.01). Higher TMAO was significantly associated with risk of hip fracture in adults with overweight or obesity (BMI ≥ 25) (HR [95% CI]:1.17[1.05,1.31]), but not normal or underweight.

CONCLUSIONS

Among older US men and women, TMAO was not significantly associated with risk of hip fracture or BMD overall. Exploratory analyses suggested a significant association between higher TMAO and hip fracture when BMI was elevated, which merits further study.

Estimating 24-Hour Urinary Excretion of Sodium and Potassium Is More Reliable from 24-Hour Urine Than Spot Urine Sample in a Feeding Study of US Older Postmenopausal Women

BACKGROUND

Assessing estimated sodium (Na) and potassium (K) intakes derived from 24-h urinary excretions compared with a spot urine sample, if comparable, could reduce participant burden in epidemiologic and clinical studies.

OBJECTIVES

In a 2-week controlled-feeding study, Na and K excretions from a 24-h urine collection were compared with a first-void spot urine sample, applying established algorithms and enhanced models to estimate 24-h excretion. Actual and estimated 24-h excretions were evaluated relative to mean daily Na and K intakes in the feeding study.

METHODS

A total of 153 older postmenopausal women ages 75.4 ± 3.5 y participated in a 2-wk controlled-feeding study with a 4-d repeating menu cycle based on their usual intake (ClinicalTrials.gov Identifier: NCT00000611). Of the 150 participants who provided both a first-void spot urine sample and a 24-h urine collection on the penultimate study day, statistical methods included Pearson correlations for Na and K between intake, 24-h collections, and the 24-h estimated excretions using 4 established algorithms: enhanced biomarker models by regressing ln-transformed intakes on ln-transformed 24-h excretions or ln-transformed 24-h estimated excretions plus participant characteristics and sensitivity analyses for factors potentially influencing Na or K excretion (e.g., possible kidney disease estimated glomerular filtration rate <60 mL/min/1.73 m2 ).

RESULTS

Pearson correlation coefficients between Na and K intakes and actual 24-h excretions were 0.57 and 0.38-0.44 for estimated 24-h excretions, depending on electrolyte and algorithm used. Enhanced biomarker model cross-validated R 2 (CVR2) for 24-h excretions were 38.5% (Na), 40.2% (K), and 42.0% (Na/K). After excluding participants with possible kidney disease, the CVR2 values were 43.2% (Na), 40.2% (K), and 38.1% (Na/K).

CONCLUSIONS

Twenty-four-hour urine excretion measurement performs better than estimated 24-h excretion from a spot urine as a biomarker for Na and K intake among a sample of primarily White postmenopausal women.

Association of vitamin D with incident glaucoma: findings from the Women's Health Initiative

The relationship between vitamin D and glaucoma is controversial. The objective of this study was to examine women from the Women's Health Initiative (WHI) to determine if there is an association between vitamin D and incident glaucoma in postmenopausal women. We examined the association between dietary vitamin D intake, vitamin D supplements and serum 25 hydroxyvitamin D (25(OH)D) levels and the risk of developing glaucoma. 143,389 postmenopausal women from the WHI including a subset with serum 25(OH) D measurements were examined to determine the association of dietary, supplemental and serum levels of vitamin D to the development of glaucoma. Dietary intakes of vitamin D, use of vitamin D supplements and serum levels of 25(OH) D were predictors examined for the main outcome of incident glaucoma. In multivariable models adjusted for demographic, clinical variables and medication use, dietary vitamin D, vitamin D supplements, total vitamin D intake (diet plus supplements) and serum 25 (OH) D measurements were not significantly associated with incident glaucoma. In the CaD placebo-controlled intervention clinical trial, there was also no association in the active intervention arm with glaucoma. We conclude that dietary vitamin D intake, supplements and serum levels are not significantly related to the risk of developing glaucoma in postmenopausal women.

Reasons for Initiation and Discontinuation of Pharmacological Therapies for Osteoporosis in Veterans with Spinal Cord Injury and Disorders

INTRODUCTION

Medications for osteoporosis have not been reported to reduce fracture rates in patients with spinal cord injury and disorders (SCI/D), yet these medications are still prescribed. Clinical decision-making underscoring the initiation and discontinuation of osteoporosis medications in SCI/D remains poorly understood.

METHODOLOGY

Veterans with a SCI/D with at least one prescription for an osteoporosis medication (bisphosphonate, calcitonin, denosumab, raloxifene, and teriparatide) who received healthcare within Veterans Affairs (VA) from 2005 to 2015 were identified using VA administrative databases. A 10% subsample of Veterans was selected for electronic health record review.

RESULTS

Two hundred and sixty-seven Veterans with 330 prescriptions underwent electronic health record review. Bisphosphonates were the most frequently prescribed medication for osteoporosis (n = 223, 67.6%). Of the 187 Veterans with prescriptions for prevention or treatment of osteoporosis, the primary reason for initiation was Dual Energy X-ray Absorptiometry (DXA) scan with osteopenia or osteoporosis (n = 119, 63.6% of Veterans), primarily at the hip (81.0% of DXAs). The majority (79.0%) of DXAs were "screening tests," with SCI/D being the sole reason for the scan. Fractures (n = 51, 27.3%) and fall risk concerns (n = 29, 15.5%) were other major reasons for initiation. On average, oral bisphosphonates were filled for <3 yr, with medication-related side effects (n = 23, 15.8% of bisphosphonates discontinued), predominately gastrointestinal (n = 17, 73.9% of reported side effects), the most common reason for discontinuation. Drug holidays occurred in 14.3% of 35 oral bisphosphonates used for ≥5 yr. No cases of osteonecrosis of the jaw were found. There was one case of an atypical femoral fracture which could not be confirmed.

CONCLUSIONS

The decision to initiate pharmacological therapies in SCI/D is primarily based on osteopenia or osteoporosis at the hip by screening DXAs. Gastrointestinal side effects are the major reason for discontinuation of oral bisphosphonates. New therapies for osteoporosis in SCI/D are needed.

Factors influencing providers' decisions on management of bone health in people with spinal cord injury

STUDY DESIGN

Survey.

OBJECTIVES

Managing osteoporosis in persons with chronic spinal cord injury (SCI) is difficult as little evidence exists regarding effective strategies. We examined the effect of key factors on providers' bone health management decisions in persons with SCI.

SETTING

USA.

METHODS

Providers reviewed blocks of 9 hypothetical cases that varied on four factors: osteoporosis, osteopenia, or normal bone mineral density using dual-energy X-ray absorptiometry (DXA); DXA region of interest (lumbar spine, hip, knee), prior lower extremity fracture; and no or limited ambulation. They indicated how likely they would recommend pharmacological management, what treatment(s) they would recommend, and whether they would request another DXA before treatment.

RESULTS

Eighty-two healthcare providers completed the survey. Treatment recommendations for bisphosphonates and Vitamin D/calcium supplements, respectively, were more likely if there was a prior fracture (OR: 2.65, 95%CI: 1.76-3.99, p < 0.0001; OR: 2.96, 95%CI: 1.40-6.26, p = 0.004) and if a DXA scan found osteopenia (OR: 2.23, 95%CI: 1.41-3.54, p = 0.001; OR: 6.56, 95%CI: 2.71-15.85, p < 0.0001) or osteoporosis (OR: 12.08, 95%CI: 7.09-20.57, p < 0.0001; OR: 4.54, 95%CI: 2.08-9.90, p < 0.0001). Another DXA scan was more likely to be requested if there was a prior fracture (OR: 1.75, 95%CI: 1.10-2.78, p = 0.02) but less likely if the person was nonambulatory (OR: 0.41, 95%: 0.19-0.90, p = 0.03).

CONCLUSIONS

Prior fracture and DXA findings influenced treatment recommendations for bone health management in SCI. Reliance on lumbar spine scans to determine bone loss and treatment identifies a knowledge gap for which future education is required.

Serial Bone Density Measurement and Incident Fracture Risk Discrimination in Postmenopausal Women

IMPORTANCE

Repeated bone mineral density (BMD) testing to screen for osteoporosis requires resources. For patient counseling and optimal resource use, it is important for clinicians to know whether repeated BMD measurement (compared with baseline BMD measurement alone) improves the ability to discriminate between postmenopausal women who will and will not experience a fracture.

OBJECTIVE

To assess whether a second BMD measurement approximately 3 years after the initial assessment is associated with improved ability to estimate fracture risk beyond the baseline BMD measurement alone.

DESIGN, SETTING, AND PARTICIPANTS

The Women's Health Initiative is a prospective observational study. Participants in the present cohort study included 7419 women with a mean (SD) follow-up of 12.1 (3.4) years between 1993 and 2010 at 3 US clinical centers. Data analysis was conducted between May 2019 and December 2019.

MAIN OUTCOMES AND MEASURES

Incident major osteoporotic fracture (ie, hip, clinical spine, forearm, or shoulder fracture), hip fracture, baseline BMD, and absolute change in BMD were assessed. The area under the receiver operating characteristic curve (AU-ROC) for baseline BMD, absolute change in BMD, and the combination of baseline BMD and change in BMD were calculated to assess incident fracture risk discrimination during follow-up.

RESULTS

Of 7419 participants, the mean (SD) age at baseline was 66.1 (7.2) years, the mean (SD) body mass index was 28.7 (6.0), and 1720 (23%) were nonwhite individuals. During the study follow-up (mean [SD] 9.0 [3.5] years after the second BMD measurement), 139 women (1.9%) experienced hip fractures, and 732 women (9.9%) experienced major osteoporotic fracture. In discriminating between women who experience hip fractures and those who do not, AU-ROC values were 0.71 (95% CI, 0.67-0.75) for baseline total hip BMD, 0.61 (95% CI, 0.56-0.65) for change in total hip BMD, and 0.73 (95% CI, 0.69-0.77) for the combination of baseline total hip BMD and change in total hip BMD. Femoral neck and lumbar spine BMD values had similar discrimination for hip fracture. For discrimination of major osteoporotic fracture, AU-ROC values were 0.61 (95% CI, 0.59-0.63) for baseline total hip BMD, 0.53 (95% CI, 0.51-0.55) for change in total hip BMD, and 0.61 (95% CI, 0.59-0.63) for the combination of baseline total hip BMD and change in total hip BMD. Femoral neck and lumbar spine BMD values had similar ability to discriminate between women who experienced major osteoporotic fracture and those who did not. Associations between change in bone density and fracture risk did not differ by subgroup, including diabetes, age, race/ethnicity, body mass index, or baseline BMD T score.

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that a second BMD assessment approximately 3 years after the initial measurement was not associated with improved discrimination between women who did and did not experience subsequent hip fracture or major osteoporotic fracture beyond the baseline BMD value alone and should not routinely be performed.

Treatment of Lower Extremity Fractures in Chronic Spinal Cord Injury: A Systematic Review of the Literature

OBJECTIVE

To review the literature regarding outcomes of surgical and nonsurgical management of lower extremity (LE) fractures in chronic spinal cord injury (SCI). TYPE: Systematic review.

LITERATURE SURVEY

Medline (PubMed), Embase, Cochrane Database of Systemic Reviews, Cochrane Central, Cumulative Index to Nursing and Allied Health Literature, ClinicalTrials.gov, International Clinical Trials Registry Platform, and International Standard Randomized Controlled Trials were searched from January 1, 1966, to March 1, 2019.

METHODOLOGY

Search was restricted to English language and adults (age ≥ 18 yr). Titles and abstracts were reviewed for relevance to study topics for inclusion. Case reports, reviews, non-SCI population studies, and studies examining fractures at the time of acute SCI were excluded. References of included articles from the original search and task force and external submissions yielded two additional articles that were included in the review after voting by task force members. Data extraction was performed by four task force members using a data extraction form, glossary, and instructions created in Microsoft Excel. Quality assessment was performed by three methodologists using prespecified criteria.

SYNTHESIS

Twenty-three articles were included. Use of surgery to treat LE fractures in chronic SCI has increased, though nonoperative management was still more frequently reported. Regardless of type of management, amputations, nonunion/malunion, and pressure injuries were among the most commonly reported complications. Functional and quality of life outcomes were less frequently reported.

CONCLUSIONS

There is insufficient evidence to support operative versus nonoperative management as best practice for management of LE fracture of SCI. Existing literature was limited by small sample sizes, lack of randomization or matched study designs, significant heterogeneity in populations and treatment strategies studied, and variability in defining and reporting outcomes of interest. The field would benefit from future research to address study design issues and standardization of outcome reporting to facilitate comparison of outcomes of operative versus nonoperative management.

Laboratory evaluation of secondary causes of bone loss in Veterans with spinal cord injury and disorders

An electronic health record (eHR) review of Veterans with a spinal cord injury and disorder (SCI/D) was conducted to understand the extent to which Veterans Affairs (VA) providers pursue workups for secondary causes of osteoporosis in this population. Laboratory tests for secondary causes were ordered in only one-third of Veterans, with secondary causes identified in two-thirds of those tested, most frequently, hypogonadism and hypovitaminosis D.

PURPOSE

To identify workups for secondary causes of osteoporosis in SCI/D and the extent to which subspecialty consultations are sought.

METHODS

A total of 3018 prescriptions for an osteoporosis medication (bisphosphonate, calcitonin, denosumab, raloxifene, teriparatide) among 2675 Veterans were identified in fiscal years 2005-2015 from VA administrative databases. Approximately 10% of these prescriptions were selected for eHR review.

RESULTS

eHR records of 187 Veterans with a SCI/D who had received pharmacological treatment for osteoporosis were reviewed. Workups for secondary causes of osteoporosis were performed in 31.5% of Veterans (n = 59) with approximately 64.4% of those tested (n = 38) having at least one abnormality. Hypogonadism (52.0% of those tested) and hypovitaminosis D (50.0% of those tested) were the most common secondary causes of osteoporosis identified in this population. Approximately 10% of primary care and SCI providers consulted subspecialists for further evaluation and treatment of osteoporosis. Endocrinologists more frequently performed a workup for secondary causes of osteoporosis compared to other provider specialties.

CONCLUSIONS

Screening for secondary causes of osteoporosis, particularly for hypogonadism and hypovitaminosis D, should be considered in patients with a SCI/D.

Predicting osteoporosis medication receipt in Veterans with a spinal cord injury: A retrospective cohort study

Objective: To describe frequency and predictors of use of pharmacological therapies for osteoporosis in persons with a spinal cord injury (SCI).Design: Retrospective cohort study.Setting: United States Veterans Health Administration (VA) national databases.Participants: 11,048 persons with a traumatic SCI who received VA health care between Fiscal Years (FY) 2005-2015. Pharmacy data from VA's Corporate Data Warehouse were used to identify prescriptions for Food and Drug Administration-approved pharmacological treatments for osteoporosis including bisphosphonates, calcitonin, denosumab, raloxifene and teriparatide.Outcome Measures: Demographics, clinical and SCI-related characteristics, receipt of a dual energy x-ray absorptiometry (DXA), and prevalent lower extremity fractures were examined to determine factors related to receiving a pharmacological agent for osteoporosis.Results: 1,041 persons (9.4%) had a prescription for a pharmacological agent for osteoporosis; the majority (n = 964, 93.0%) were bisphosphonates. There was a significant decline in the number of these prescriptions from FY 2005 (13.0%) to FY 2015 (2.2%). In multivariable analysis, age (>50 years) (OR = 1.60, 95% CI 1.31-1.94); female sex (OR = 4.09, 95% CI 2.74-6.09); opioid (OR = 1.24, 95% CI 1.01-1.51) or corticosteroid (OR = 1.92, 95% CI 1.01-1.51) prescriptions; complete injury (OR = 1.26, 95% CI 1.04-1.53); receipt of a DXA scan (OR = 84.03, 95% CI 59.80-118.07) and prevalent fracture (OR = 5.43, 95% CI 4.13-7.15) were positive predictors. Black race (OR = 0.43, 95% CI 0.33-0.57) and obese BMI (OR = 0.59, 95% CI 0.45-0.76) were negative predictors.Conclusions: Prescriptions for osteoporosis medications for persons with a SCI declined in recent years. The strongest predictors for having filled these prescriptions were having had a DXA or a prevalent fracture.

Bone Mineral Density Testing in Spinal Cord Injury: 2019 ISCD Official Position

Spinal cord injury (SCI) causes rapid osteoporosis that is most severe below the level of injury. More than half of those with motor complete SCI will experience an osteoporotic fracture at some point following their injury, with most fractures occurring at the distal femur and proximal tibia. These fractures have devastating consequences, including delayed union or nonunion, cellulitis, skin breakdown, lower extremity amputation, and premature death. Maintaining skeletal integrity and preventing fractures is imperative following SCI to fully benefit from future advances in paralysis cure research and robotic-exoskeletons, brain computer interfaces and other evolving technologies. Clinical care has been previously limited by the lack of consensus derived guidelines or standards regarding dual-energy X-ray absorptiometry-based diagnosis of osteoporosis, fracture risk prediction, or monitoring response to therapies. The International Society of Clinical Densitometry convened a task force to establish Official Positions for bone density assessment by dual-energy X-ray absorptiometry in individuals with SCI of traumatic or nontraumatic etiology. This task force conducted a series of systematic reviews to guide the development of evidence-based position statements that were reviewed by an expert panel at the 2019 Position Development Conference in Kuala Lumpur, Malaysia. The resulting the International Society of Clinical Densitometry Official Positions are intended to inform clinical care and guide the diagnosis of osteoporosis as well as fracture risk management of osteoporosis following SCI.

The renin-angiotensin aldosterone system and osteoporosis: findings from the Women's Health Initiative

New users of RAAS inhibitors, including ACE inhibitors and ARBs, have a small increased risk for fracture in the first 3 years of use, with a reduced risk of fracture with longer duration of use.

INTRODUCTION

Pharmacological inhibitors of the renin-angiotensin aldosterone system (RAAS) are used to treat hypertension. However, the relationship of these medications to osteoporosis is inconsistent, and no study has included simultaneous measurements of both incident fractures and bone mineral density (BMD).

METHODS

The association of RAAS inhibitor use (n = 131,793) with incident fractures in new users of these medications in women in the Women's Health Initiative over a minimum median follow-up of 6.5 years was assessed by Cox proportional hazard models. The association of incident fractures by a cumulative duration of use of these medications (< 3 years.) and (> 3 years.) was also estimated. Subgroup analysis of fracture risk by RAAS inhibitor use confined to women with hypertension was also performed (n = 33,820). The association of RAAS inhibitor use with changes in BMD of the hip was estimated by linear regression in 8940 women with dual energy X-ray absorptiometry measurements.

RESULTS

There was no significant association between RAAS inhibitor use and all fractures in the final adjusted multivariable models including hip BMD (HR 0.86 (0.59, 1.24)). However, among users of RAAS inhibitors, including ACE inhibitors and angiotensin receptor blockers (ARBs), hazard ratios for all incident fracture sites in final multivariable models including hip BMD showed dramatic differences by duration of use, with short duration of use (3 years or less) associated with a marked increased risk for fracture (HR 3.28 (1.66, 6.48)) to (HR 6.23 (3.11, 12.46)) and use for more than 3 years associated with a reduced fracture risk (HR 0.40 (0.24, 0.68) to (HR 0.44 (0.20, 0.97)) . Findings were similar in the subgroup of women with a history of hypertension. There was no significant change in BMD of the hip by RAAS inhibitor use.

CONCLUSIONS

In postmenopausal women, use of RAAS inhibitors, including ACE inhibitors and ARBs, is associated with an increased risk for fracture among new users of these medications in the first 3 years of use. However, long-term use (> 3 years) is associated with a reduced risk. Consideration for fracture risk may be part of the decision-making process for initiation of these medications for other disease states.

The Association of Aromatic Amino Acids with Incident Hip Fracture, aBMD, and Body Composition from the Cardiovascular Health Study

In 5187 persons from the Cardiovascular Health Study, there was no significant association of dietary intakes of aromatic amino acids (AAA) with areal BMD of the hip or body composition. However, those who had the lowest dietary intakes of AAA were at increased risk for incident hip fractures. Prior studies of the association of protein intake with osteoporosis are conflicting and have not directly examined the relationship of aromatic amino acids (AAA) with fractures, areal bone mineral density (aBMD), and body composition. We sought to determine the relationship of dietary intakes of AAA with osteoporosis parameters in elderly men and women. 5187 men and women aged ≥ 65 years from the Cardiovascular Health Study (CHS) with dietary intakes of AAA (tryptophan, phenylalanine, tyrosine) estimated by food frequency questionnaire (FFQ) were included. We examined the relationship between a one-time estimate of daily dietary AAA intake with risk of incident hip fractures over a median of 13.2 years of fracture follow-up. A subset (n = 1336) who had dual energy X-ray absorptiometry (DXA) performed were included in a cross-sectional analysis of the association of dietary AAA intake with aBMD of the total hip and measurements of body composition. In multivariable models adjusted for demographic and clinical variables, medication use, and diet, higher dietary AAA intake was not significantly associated with incident hip fractures. All hazard ratios (HR) were less than one (tryptophan, HR 0.14, 95% CI 0.01 to 1.89; phenylalanine, HR 0.60, 95% CI 0.23 to 1.55; tyrosine, HR 0.59, 95% CI 0.27 to 1.32), but confidence intervals were wide and included no difference. However, in post hoc analyses, the lowest quartile of intake for each AAA was associated with an increased risk for hip fracture compared to higher quartiles (p ≤ 0.047 for all). Dietary AAA intakes were not significantly associated with total hip aBMD or any measurements of body composition. Overall, there was no significant association of dietary AAA intake with hip fractures, aBMD of the hip, or body composition. However, there may be a subset of elderly individuals with low dietary intakes of AAA who are at increased for hip fractures.

Association of Dietary Niacin Intake With Incident Hip Fracture, BMD, and Body Composition: The Cardiovascular Health Study

Interest in niacin has increased in the setting of reports suggesting that niacin plays a role in diseases of aging. No study to date has examined the association of dietary niacin intake with multiple skeletal health parameters including bone mineral density (BMD), hip fractures, and body composition, and none have included both African American and white men and women. Participants included 5187 men and women ≥65 years from the Cardiovascular Health Study (CHS). Mean daily dietary niacin intake was 32.6 mg, with quartiles 1 through 4 defined as 3.6 to 21.8 mg/day, 21.9 to 30.2 mg/day, 30.3 to 40.9 mg/day, and 41.0 to 102.4 mg/day, respectively. Risk of incident hip fracture per 10 mg increment of daily dietary niacin intake was estimated using proportional hazards models. During a median follow-up of 13 years, 725 participants had an incident hip fracture. In models adjusted for demographic and clinical characteristics and diet, dietary niacin intake was significantly associated with an increased risk of hip fractures (hazard ratio [HR] 1.12; 95% CI, 1.01 to 1.24) with spline models suggesting a U-shaped association. In post hoc analyses, both the lowest (HR 1.31; 95% CI, 1.04 to 1.66) and highest (HR 1.53; 95% CI, 1.20 to 1.95) quartiles of niacin intake were associated with an increased risk of incident hip fracture versus quartiles 2 and 3. There was a trend for a significant inverse association of dietary niacin intake with hip BMD (p = 0.06), but no significant association with total body BMD or any body composition measures. In this cohort of elderly, community-dwelling African American and white men and women, both high and low dietary niacin intakes were associated with a significantly increased risk of subsequent hip fracture, suggesting a possible U-shaped association. By comparison, dietary niacin may have an inverse linear association with hip BMD. © 2018 American Society for Bone and Mineral Research.

Associations of Biomarker-Calibrated Sodium and Potassium Intakes With Cardiovascular Disease Risk Among Postmenopausal Women

Studies of the associations of sodium and potassium intakes with cardiovascular disease incidence often rely on self-reported dietary data. In the present study, self-reported intakes from postmenopausal women at 40 participating US clinical centers are calibrated using 24-hour urinary excretion measures in cohorts from the Women's Health Initiative, with follow-up from 1993 to 2010. The incidence of hypertension was positively related to (calibrated) sodium intake and to the ratio of sodium to potassium. The sodium-to-potassium ratio was associated with cardiovascular disease incidence during an average follow-up period of 12 years. The estimated hazard ratio for a 20% increase in the sodium-to-potassium ratio was 1.13 (95% confidence interval (CI): 1.04, 1.22) for coronary heart disease, 1.20 (95% CI: 1.01, 1.42) for heart failure, and 1.11 (95% CI: 1.04, 1.19) for a composite cardiovascular disease outcome. The association with total stroke was not significant, but it was positive for ischemic stroke and inverse for hemorrhagic stroke. Aside from hemorrhagic stroke, corresponding associations of cardiovascular disease with sodium and potassium jointly were positive for sodium and inverse for potassium, although some were not statistically significant. Specifically, for coronary heart disease, the hazard ratios for 20% increases were 1.11 (95% CI: 0.95, 1.30) for sodium and 0.85 (95% CI: 0.73, 0.99) for potassium; and corresponding values for heart failure were 1.36 (95% CI: 1.02, 1.82) for sodium and 0.90 (95% CI: 0.69, 1.18) for potassium.

Association of Plasma SDF-1 with Bone Mineral Density, Body Composition, and Hip Fractures in Older Adults: The Cardiovascular Health Study

Aging is associated with an increase in circulating inflammatory factors. One, the cytokine stromal cell-derived factor 1 (SDF-1 or CXCL12), is critical to stem cell mobilization, migration, and homing as well as to bone marrow stem cell (BMSC), osteoblast, and osteoclast function. SDF-1 has pleiotropic roles in bone formation and BMSC differentiation into osteoblasts/osteocytes, and in osteoprogenitor cell survival. The objective of this study was to examine the association of plasma SDF-1 in participants in the cardiovascular health study (CHS) with bone mineral density (BMD), body composition, and incident hip fractures. In 1536 CHS participants, SDF-1 plasma levels were significantly associated with increasing age (p < 0.01) and male gender (p = 0.04), but not with race (p = 0.63). In multivariable-adjusted models, higher SDF-1 levels were associated with lower total hip BMD (p = 0.02). However, there was no significant association of SDF-1 with hip fractures (p = 0.53). In summary, circulating plasma levels of SDF-1 are associated with increasing age and independently associated with lower total hip BMD in both men and women. These findings suggest that SDF-1 levels are linked to bone homeostasis.

Association of DPP-4 activity with BMD, body composition, and incident hip fracture: the Cardiovascular Health Study

There was no association of plasma DPP-4 activity levels with bone mineral density (BMD), body composition, or incident hip fractures in a cohort of elderly community-dwelling adults.

INTRODUCTION

Dipeptidyl peptidase IV (DPP-4) inactivates several key hormones including those that stimulate postprandial insulin secretion, and DPP-4 inhibitors (gliptins) are approved to treat diabetes. While DPP-4 is known to modulate osteogenesis, the relationship between DPP-4 activity and skeletal health is uncertain. The purpose of the present study was to examine possible associations between DPP-4 activity in elderly subjects enrolled in the Cardiovascular Health Study (CHS) and BMD, body composition measurements, and incident hip fractures.

METHODS

All 1536 male and female CHS participants who had evaluable DXA scans and plasma for DPP-4 activity were included in the analyses. The association between (1) BMD of the total hip, femoral neck, lumbar spine, and total body; (2) body composition measurements (% lean, % fat, and total body mass); and (3) incident hip fractures and plasma levels of DPP-4 activity were determined.

RESULTS

Mean plasma levels of DPP-4 activity were significantly higher in blacks (227 ± 78) compared with whites (216 ± 89) (p = 0.04). However, there was no significant association of DPP-4 activity with age or gender (p ≥ 0.14 for both). In multivariable adjusted models, there was no association of plasma DPP-4 activity with BMD overall (p ≥ 0.55 for all) or in gender stratified analyses (p ≥ 0.23). There was also no association of DPP-4 levels and incident hip fractures overall (p ≥ 0.24) or in gender stratified analyses (p ≥ 0.39).

CONCLUSION

Plasma DPP-4 activity, within the endogenous physiological range, was significantly associated with race, but not with BMD, body composition, or incident hip fractures in elderly community-dwelling subjects.

Bone Mineral Density and Risk of Heart Failure in Older Adults: The Cardiovascular Health Study

BACKGROUND

Despite increasing evidence of a common link between bone and heart health, the relationship between bone mineral density (BMD) and heart failure (HF) risk remains insufficiently studied.

METHODS AND RESULTS

We investigated whether BMD measured by dual-energy x-ray absorptiometry was associated with incident HF in an older cohort. Cox models were stratified by sex and interactions of BMD with race assessed. BMD was examined at the total hip and femoral neck separately, both continuously and by World Health Organization categories. Of 1250 participants, 442 (55% women) developed HF during the median follow-up of 10.5 years. In both black and nonblack women, neither total hip nor femoral neck BMD was significantly associated with HF; there was no significant interaction by race. In black and nonblack men, total hip, but not femoral neck, BMD was significantly associated with HF, with evidence of an interaction by race. In nonblack men, lower total hip BMD was associated with higher HF risk (hazard ratio, 1.13 [95% CI, 1.01-1.26] per 0.1 g/cm2 decrement), whereas in black men, lower total hip BMD was associated with lower HF risk (hazard ratio, 0.74 [95% CI, 0.59-0.94]). There were no black men with total hip osteoporosis. Among nonblack men, total hip osteoporosis was associated with higher HF risk (hazard ratio, 2.83 [95% CI, 1.39-5.74]) compared with normal BMD.

CONCLUSIONS

Among older adults, lower total hip BMD was associated with higher HF risk in nonblack men but lower risk in black men, with no evidence of an association in women. Further research is needed to replicate these findings and to study potential underlying pathways.

Dual-energy X-ray absorptiometry and fracture prediction in patients with spinal cord injuries and disorders

Low T-scores at the hip predict incident fractures in persons with a SCI.

INTRODUCTION

Persons with a spinal cord injury (SCI) have substantial morbidity and mortality following osteoporotic fractures. The objective of this study was to determine whether dual-energy X-ray absorptiometry (DXA) measurements predict osteoporotic fractures in this population.

METHODS

A retrospective historical analysis that includes patients (n = 552) with a SCI of at least 2 years duration who had a DXA performed and were in the VA Spinal Cord Disorders Registry from fiscal year (FY) 2002-2012 was performed.

RESULTS

The majority of persons (n = 455, 82%) had a diagnosis of osteoporosis or osteopenia, with almost half having osteoporosis. BMD and T-scores at the lumbar spine were not significantly associated with osteoporotic fractures (p > 0.48) for both. In multivariable analyses, osteopenia (OR = 4.75 95% CI 1.23-17.64) or osteoporosis (OR = 4.31, 95% CI 1.15-16.23) compared with normal BMD was significantly associated with fractures and higher T-scores at the hip were inversely associated with fractures (OR 0.73 (95% CI 0.57-0.92)). There was no significant association of T-scores or World Health Organization (WHO) classification with incident fractures in those with complete SCI (p > 0.15 for both).

CONCLUSION

The majority (over 80%) of individuals with a SCI have osteopenia or osteoporosis. DXA-derived measurements at the hip, but not the lumbar spine, predict fracture risk in persons with a SCI. WHO-derived bone density categories may be useful in classifying fracture risk in persons with a SCI.

Use of My HealtheVet patient web portal among veterans seen for diabetes mellitus at a medical center in the southeastern United States

BACKGROUND

An increasing number of studies have examined the use of information technology to improve diabetes care and patient self-management. The goal of the current study was to determine the number of veterans seen for diabetes at a large medical center in the southeastern region of the U.S. and to examine whether they had registered for VA's My HealtheVet patient web portal according to selected characteristics.

METHODS

Existing patient records were reviewed including My HealtheVet web portal registration by veterans treated for diabetes (ICD-10 code for type 2 diabetes) at the Charlie Norwood VAMC. Number of outpatient clinic patients seen for diabetes who had or had not registered for My HealtheVet were examined by age categories, sex, race, Hispanic ethnicity, and era of military service.

RESULTS

A total of 49,341 veterans receive care at the Charlie Norwood VAMC. Of those patients, 10,950 have been seen for diabetes. Of the 49,341 patients, 21,372 patients (43.3%) are using My HealtheVet and 10,465 patients (21.2%) have used secure messages. Of 10,950 diabetic patients, only 1,256 (11.5%) have registered for My HealtheVet. Women with diabetes were more likely to be registered for My HealtheVet than their male counterparts [13.92% vs. 11.24%; odds ratio (OR)=1.28; 95% confidence interval (CI): 1.05-1.55). Veterans with diabetes who served during WW II or the Korean War were less likely to use My HealtheVet than those who served during more recent eras (OR=0.33; 95% CI: 0.24-0.44). Use of the patient portal was highest among diabetic patients ages 51-55 years (15.6%).

CONCLUSIONS

A low percentage of Veterans with diabetes are active users of My HealtheVet. Studies are needed to identify My HealtheVet portal design features and veteran characteristics that will increase use of this patient portal which may improve diabetes care.

A historical study of appendicular fractures in veterans with traumatic chronic spinal cord injury: 2002-2007

OBJECTIVE

Describe the incidence and distribution of appendicular fractures in a cohort of veterans with spinal cord injury (SCI).

DESIGN

Retrospective, observational study of fractures in veterans with a chronic traumatic SCI.

SETTING

The Veterans Health Administration (VA) healthcare system.

PARTICIPANTS

Veterans included in the VA Spinal Cord Dysfunction Registry from Fiscal Years (FY) FY2002-FY2007.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Description of fractures by site and number. Mortality at one year following incident fracture among men with single vs. multiple fractures.

RESULTS

Male and female veterans sustained incident fractures with similar observed frequency (10.5% vs 11.5%). The majority of fractures occurred in the lower extremities for both men and women. In men, a complete extent of injury (compared to incomplete) was associated with 41% greater relative risk (RR) of incident fracture (RR 1.41, 95% confidence interval [1.17, 1.70]) among those with tetraplegia, but not paraplegia. Furthermore, many men (33.9%, n = 434) sustained multiple fractures over the course of the study. There were no differences in mortality between men who sustained a single fracture and those who had multiple fractures.

CONCLUSIONS

The extent of injury may be an important predictor of fracture risk for male veterans with tetraplegia. Once a fracture occurs, male veterans with SCI appear to be at high risk for additional fractures.

Risk factors for osteoporotic fractures in persons with spinal cord injuries and disorders

Clinical risk factors for fracture were explored among Veterans with a spinal cord injury. At the end of 11 years of follow-up, the absolute risk of fracture was approximately 20 %. Among the clinical and SCI-related factors explored, a prior history of fracture was strongly associated with incident fracture.

INTRODUCTION

Few studies to date have comprehensively addressed clinical risk factors for fracture in persons with spinal cord injury (SCI). The purpose of this study was to identify risk factors for incident osteoporotic fractures in persons with a SCI that can be easily determined at the point of care.

METHODS

The Veteran's Affairs Spinal Cord Dysfunction Registry, a national database of persons with a SCI, was used to examine clinical and SCI-related risk factors for fracture. Incident fractures were identified in a cohort of persons with chronic SCI, defined as SCI present for at least 2 years. Cox regression models were used to estimate the risk of incident fractures.

RESULTS

There were 22,516 persons with chronic SCI included in the cohort with 3365 incident fractures. The mean observational follow-up time for the overall sample was 6.2 years (median 6.0, IQR 2.9-11.0). The mean observational follow-up time for the fracture group was 3.9 years (median 3.3, IQR 1.4-6.1) and 6.7 years (median 6.7, IQR 3.1-11.0) for the nonfracture group. By the end of the study, which included predominantly older Veterans with a SCI observed for a relatively short period of time, the absolute (i.e., cumulative hazard) for incident fractures was 0.17 (95%CI 0.14-0.21). In multivariable analysis, factors associated with an increased risk of fracture included White race, traumatic etiology of SCI, paraplegia, complete extent of SCI, longer duration of SCI, use of anticonvulsants and opioids, prevalent fractures, and higher Charlson Comorbidity Indices. Women aged 50 and older were also at higher risk of sustaining an incident fracture at any time during the 11-year follow-up period.

CONCLUSIONS

There are multiple clinical and SCI-related risk factors which can be used to predict fracture in persons with a SCI. Clinicians should be particularly concerned about incident fracture risk in persons with a SCI who have had a previous fracture.

Soluble CD14 and fracture risk

Soluble CD14 (sCD14) is an inflammatory marker associated with osteoclasts. Using Cox proportional hazards models, we found a positive association between plasma levels of sCD14 and risk of incident fracture among participants in the Cardiovascular Health Study. sCD14 may be useful in identifying those at risk for fracture.

INTRODUCTION

Soluble CD14, a proinflammatory cytokine, is primarily derived from macrophages/monocytes that can differentiate into osteoclasts. The purpose of this study was to examine the relationship between sCD14 levels and osteoporotic fractures.

METHODS

In the Cardiovascular Health Study, 5462 men and women had sCD14 levels measured at baseline. Incident hip fractures (median follow-up time 12.5 years) and incident composite fractures (defined as the first hip, pelvis, humerus, or distal radius fracture, median follow-up 8.6 years) were identified from hospital discharge summaries and/or Medicare claims data. Cox proportional hazards models were used to model the association between sCD14 levels and time to incident hip or composite fracture, overall and as a function of race and gender.

RESULTS

In unadjusted models, there was a positive association between sCD14 levels (per 1 standard deviation increase, i.e., 361.6 ng/mL) and incident hip (HR, 1.26; 95 % CI, 1.17, 1.36) and composite (HR, 1.20; 95 % CI, 1.12, 1.28) fractures. When models were fully adjusted for demographics, lifestyle factors, and medication use, these associations were no longer significant. However, in whites, the association of sCD14 levels with hip fractures remained significant in fully adjusted models (HR, 1.11; 95 % CI, 1.01-1.23). Associations of sCD14 levels with hip and composite fracture did not differ between men and women.

CONCLUSIONS

In this large cohort of community-dwelling older adults, higher sCD14 levels were associated with an increased risk of incident hip fractures in whites.

Hydroxychloroquine in patients with systemic lupus erythematosus with end-stage renal disease

OBJECTIVES

To determine dosing patterns and examine predictors of filled hydroxychloroquine (HCQ) prescriptions in patients with systemic lupus erythematosus (SLE) with end-stage renal disease (ESRD).

METHODS

This was a retrospective cohort study of patients with SLE in the US Renal Data System (USRDS) database in fiscal year 2011. All patients were Medicare Part D beneficiaries. Patients with a diagnosis of SLE were identified by the International Classification of Diseases, 9th revision code 710. The prevalence, dosing, and predictors of filled HCQ prescriptions (demographic factors, dialysis type, and provider subspecialty) were determined.

RESULTS

There were 10,276 patients with SLE identified; 2048 (19.9%) had a prescription for HCQ filled. The mean daily dose of HCQ was 321 mg (range 58-2000 mg). The most common daily doses were 200 (n=768, 37.5%) and 400 mg (n=1161, 56.7%). In multivariable logistic regression analysis, significant predictors of filled HCQ prescriptions included black/African-American race (OR 1.34, 95% CI (1.17 to 1.46)), hemodialysis (1.50, 95% CI (1.29 to 1.74)), and care from a rheumatologist (5.06, 95% CI (4.56 to 5.62)). Negative predictors of filled HCQ prescriptions included male gender (OR 0.72, 95% CI (0.63 to 0.83)) and those aged 45 years or older (compared to 20 years old and younger, aged 45-64 years, OR 0.66, 95% CI (0.54 to 0.79); aged 65-74 years, OR 0.58, 95% CI (0.44 to 0.76); aged 75 years and older, OR 0.56, 95% CI (0.39 to 0.82)).

CONCLUSIONS

In patients with SLE with ESRD, the dosing strategies for HCQ with regard to potential toxicity and disparities in prescribing patterns need further study.

Urinary Tract Stones and Osteoporosis: Findings From the Women's Health Initiative

Kidney and bladder stones (urinary tract stones) and osteoporosis are prevalent, serious conditions for postmenopausal women. Men with kidney stones are at increased risk of osteoporosis; however, the relationship of urinary tract stones to osteoporosis in postmenopausal women has not been established. The purpose of this study was to determine whether urinary tract stones are an independent risk factor for changes in bone mineral density (BMD) and incident fractures in women in the Women's Health Initiative (WHI). Data were obtained from 150,689 women in the Observational Study and Clinical Trials of the WHI with information on urinary tract stones status: 9856 of these women reported urinary tract stones at baseline and/or incident urinary tract stones during follow-up. Cox regression models were used to determine the association of urinary tract stones with incident fractures and linear mixed models were used to investigate the relationship of urinary tract stones with changes in BMD that occurred during WHI. Follow-up was over an average of 8 years. Models were adjusted for demographic and clinical factors, medication use, and dietary histories. In unadjusted models there was a significant association of urinary tract stones with incident total fractures (HR 1.10; 95% CI, 1.04 to 1.17). However, in covariate adjusted analyses, urinary tract stones were not significantly related to changes in BMD at any skeletal site or to incident fractures. In conclusion, urinary tract stones in postmenopausal women are not an independent risk factor for osteoporosis.

Bone turnover in long-term survivors of childhood acute lymphoblastic leukemia

BACKGROUND

We investigated the effects of demographic, lifestyle (self-reported smoking status and physical activity levels), cancer-related treatment factors (radiation and chemotherapy), and diet (calcium and vitamin D intake) on bone turnover and the relationship of bone turnover to lumbar spine bone mineral density (BMD) Z-scores (LS-BMD Z-scores) determined by quantitative computed tomography (QCT) in 418 ≥5-year survivors of childhood acute lymphoblastic leukemia (ALL).

PROCEDURE

Bone turnover was assessed by biomarkers including serum bone-specific alkaline phosphatase (BALP), osteocalcin (OC), and urinary N-telopeptide of type I collagen indexed to creatinine (NTX/Cr). The 215 males ranged in age from 9 to 36 years (median age 17 years).

RESULTS

Age and tanner score were inversely associated with all biomarkers (BALP, OC, NTX/Cr) (P < 0.001). Males had higher BALP and OC than females (P < 0.001). Body mass index (BMI) was inversely associated with OC and NTX/Cr (P < 0.001). There was no significant association of biomarkers with lifestyle related factors, ALL treatment-related factors, dietary calcium, vitamin D, or LS-BMD Z-score.

CONCLUSIONS

In this population of long-term survivors of ALL, bone turnover was significantly associated with age, gender, tanner stage, and BMI. ALL-related treatments did not influence bone turnover and bone turnover was not predictive of volumetric LS-BMD Z-score.

Mortality after lower extremity fractures in men with spinal cord injury

In the United States, there are over 200,000 men with spinal cord injuries (SCIs) who are at risk for lower limb fractures. The risk of mortality after fractures in SCI is unknown. This was a population-based, cohort study of all male veterans (mean age 54.1; range, 20.3-100.5 years) with a traumatic SCI of at least 2 years' duration enrolled in the Veterans Affairs (VA) Spinal Cord Dysfunction Registry from FY2002 to FY2010 to determine the association between lower extremity fractures and mortality. Mortality for up to 5 years was determined. The lower extremity fracture rate was 2.14 per 100 patient-years at risk for at least one fracture. In unadjusted models and in models adjusted for demographic, SCI-related factors, healthcare use, and comorbidities, there was a significant association between incident lower extremity fracture and increased mortality (hazard ratio [HR], 1.38; 95% confidence interval [CI], 1.17-1.63; HR, 1.36; 95% CI, 1.15-1.61, respectively). In complete SCI, the hazard of death after lower extremity fracture was also increased (unadjusted model: HR, 1.46; 95% CI, 1.13-1.89; adjusted model: HR, 1.32; 95% CI, 1.02-1.71). In fully-adjusted models, the association of incident lower extremity fracture with increased mortality was substantially greater in older men (age ≥50 years) for the entire cohort (HR, 3.42; 95% CI, 2.75-4.25) and for those with complete SCI (HR, 3.13; 95% CI, 2.19-4.45), compared to younger men (age <50 years) (entire cohort: HR, 1.42; 95% CI, 0.94-2.14; complete SCI: HR, 1.71; 95% CI, 0.98-3.01). Every additional point in the Charlson comorbidity index was associated with a 10% increase in the hazard of death in models involving the entire cohort (HR, 1.11; 95% CI, 1.09-1.13) and also in models limited to men with complete SCI (HR, 1.10; 95% CI, 1.06-1.15). These data support the concept that both the fracture itself and underlying comorbidities are drivers of death in men with SCI.

Morbidity following lower extremity fractures in men with spinal cord injury

The Veterans Affairs Spinal Cord Dysfunction Registry from 2002 to 2007 was reviewed to determine whether men with spinal cord injury (SCI) and lower extremity fractures had an increased risk of complications compared to those without fractures. We determined that fractures are associated with significant consequences, particularly during the first month postfracture.

INTRODUCTION

Despite increasing longevity, patients with SCI have a substantial number of illnesses and comorbid conditions. Lower extremity fractures are frequent events in these patients. However, whether these fractures are associated with any increased risk of complications in SCI is not certain. The purpose of this report was to determine the impact of lower extremity fractures on morbidities in men with SCI.

METHODS

A population-based, nested, case-control (1,027 cases and 1,027 propensity-matched controls) of men enrolled in the Veterans Affairs Spinal Cord Dysfunction Registry from fiscal years 2002 to 2007 was reviewed to determine whether lower extremity fractures were associated with an increased risk for complications.

RESULTS

In propensity score models matched for demographic (age, race) and SCI-related injury factors (level/completeness of SCI), Veterans Affairs-service connection status, and comorbidities, at 1 month following the fracture, there was an increased risk for respiratory infections, pressure ulcers, urinary tract infections, thromboembolic events, depression, and delirium (p ≤ 0.03 for all). Over 12 months, the only complication more common in fracture cases was pressure ulcers (p < 0.01), with an absolute difference of less than 2 % when compared to controls. There was no significant increased risk of cardiac arrhythmias at any time examined following fracture (≥0.12).

CONCLUSIONS

Lower extremity fractures are associated with significant consequences in men with SCI during the first month postfracture, but they do not persist for a long term, except for pressure ulcers. Targeted interventions to prevent complications should be considered following lower extremity fractures in SCI, particularly in the first month following fracture.

Estrogen alone and joint symptoms in the Women's Health Initiative randomized trial

OBJECTIVE

Although joint symptoms are commonly reported after menopause, observational studies examining exogenous estrogen's influence on joint symptoms provide mixed results. Against this background, estrogen-alone effects on joint symptoms were examined in post hoc analyses in the Women's Health Initiative randomized, placebo-controlled, clinical trial.

METHODS

A total of 10,739 postmenopausal women who have had a hysterectomy were randomized to receive daily oral conjugated equine estrogens (0.625 mg/d) or a matching placebo. The frequency and severity of joint pain and joint swelling were assessed by questionnaire in all participants at entry and on year 1, and in a 9.9% random subsample (n = 1,062) after years 3 and 6. Logistic regression models were used to compare the frequency and severity of symptoms by randomization group. Sensitivity analyses evaluated adherence influence on symptoms.

RESULTS

At baseline, joint pain and joint swelling were closely comparable in the randomization groups (about 77% with joint pain and 40% with joint swelling). After 1 year, joint pain frequency was significantly lower in the estrogen-alone group compared with the placebo group (76.3% vs 79.2%, P = 0.001), as was joint pain severity, and the difference in pain between randomization groups persisted through year 3. However, joint swelling frequency was higher in the estrogen-alone group (42.1% vs 39.7%, P = 0.02). Adherence-adjusted analyses strengthen estrogen's association with reduced joint pain but attenuate estrogen's association with increased joint swelling.

CONCLUSIONS

The current findings suggest that estrogen-alone use in postmenopausal women results in a modest but sustained reduction in the frequency of joint pain.

The association of opioid use with incident lower extremity fractures in spinal cord injury

OBJECTIVE

To determine the association between opioid use and lower extremity fracture risk in men with spinal cord injury (SCI).

DESIGN

Retrospective cohort study.

SETTING

Veterans Affairs Healthcare System.

PARTICIPANTS

In total, 7447 male Veterans with a history of a traumatic SCI identified from the Veterans Affairs (VA) Spinal Cord Dysfunction Registry (SCD) from September 2002 through October 2007 and followed through October 2010.

OUTCOME MEASURES

Incident lower extremity fractures by use of opioids.

RESULTS

In individuals identified from the VA SCD Registry 2002-2007, opioid use was quite common, with approximately 70% of the cohort having received a prescription for an opioid. Overall, there were 892 incident lower extremity fractures over the time period of this study (597 fractures in the opioid users and 295 fractures in the non-opioid users). After adjusting for covariates, there was a statistically significant relationship between opioid use and increased risk for lower extremity fractures (hazard ratio 1.82 (95% confidence interval 1.59-2.09)). Shorter duration of use (<6 months) and higher doses were positively related to fracture risk (P < 0.0001).

CONCLUSIONS

Opioid use is quite common in SCI and is associated with an increased risk for lower extremity fractures. Careful attention to fracture prevention is warranted in patients with SCI, particularly upon initiation of an opioid prescription and when higher doses are used.

Assistive walking device use and knee osteoarthritis: results from the Health, Aging and Body Composition Study (Health ABC Study)

OBJECTIVES

To identify factors that predicted incident use of assistive walking devices (AWDs) and to explore whether AWD use was associated with changes in osteoarthritis of the knee.

DESIGN

Prospective cohort study.

SETTING

Community.

PARTICIPANTS

Older adults (N=2639) in the Health, Aging and Body Composition (Health ABC) Study including a subset of 874 patients with prevalent knee pain.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Incident use of AWDs, mean Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scores, and the frequency of joint space narrowing on knee radiographs over a 3-year time period.

RESULTS

AWD use was initiated by 9% of the entire Health ABC cohort and 12% of the knee pain subset. Factors that predicted use in both groups were age ≥73 (entire cohort: odds ratio [OR]=2.07; 95% confidence interval [CI], 1.43-3.01; knee pain subset: OR=1.87; 95% CI, 1.16-3.03), black race (entire cohort: OR=2.95; 95% CI, 2.09-4.16; knee pain subset: OR=3.21; 95% CI, 2.01-5.11), and lower balance ratios (entire cohort: OR=3.18; 95% CI, 2.21-4.59; knee pain subset: OR=3.77; 95% CI, 2.34-6.07). Mean WOMAC pain scores decreased slightly over time in both AWD and non-AWD users. Twenty percent of non-AWD users and 28% of AWD users had radiographic progression in joint space narrowing of the tibiofemoral joint in at least 1 knee. Fourteen percent of non-AWD users and 12% of AWD users had radiographic progression in joint space narrowing in the patellofemoral joint in at least 1 knee.

CONCLUSIONS

AWDs are frequently used by older adults. Knee pain and balance problems are significant reasons why older adults initiate use of an AWD. In an exploratory analysis, there was no consistent relation between the use or nonuse of an AWD and WOMAC pain scores or knee joint space narrowing progression. Further studies of the relation of use of AWDs to changes in knee osteoarthritis are needed.

Muscle strength, mass, and quality in older men and women with knee osteoarthritis

OBJECTIVE

To examine the relationship between knee osteoarthritis (OA) and muscle parameters in a biracial cohort of older adults.

METHODS

Participants in the Health, Aging and Body Composition Study (n = 858) were included in this cross-sectional analysis. Computed tomography was used to measure muscle area, and quadriceps strength was measured isokinetically. Muscle quality (specific torque) was defined as strength per unit of muscle area for both the entire thigh and quadriceps. Knee OA was assessed based on radiographic features and knee pain. We compared muscle parameters between those with and without radiographic knee OA (+RKOA group and -RKOA group, respectively) and among 4 groups defined by +RKOA and -RKOA with and without pain.

RESULTS

The mean ± SD age was 73.5 ± 2.9 years and the mean ± SD body mass index (BMI) was 27.9 ± 4.8 kg/m(2) . Fifty-eight percent of participants were women and 44% were African American. Compared to the -RKOA participants, +RKOA participants had a higher BMI (30.2 versus 26.8 kg/m(2)), larger thigh muscles (117.9 versus 108.9 cm(2)), and a greater amount of intermuscular fat (12.5 versus 9.9 cm(2) ; all P < 0.0001). In adjusted models, the +RKOA participants had significantly lower specific torque (P < 0.001), indicating poorer muscle quality, than -RKOA participants, but there was no difference between groups in quadriceps specific torque. The +RKOA without pain (P < 0.05) and the +RKOA with pain (P < 0.001) participants had lower specific torque compared to the -RKOA without pain group. There were no significant differences in quadriceps specific torque among groups.

CONCLUSION

Muscle quality was significantly poorer in participants with RKOA regardless of pain status. Future studies should address how lifestyle interventions might affect muscle quality and progression of knee OA.

Osteoporosis care in the United States after declines in reimbursements for DXA

In January 2007, in the United States (US), Medicare initiated a series of cuts to reimbursement for dual-energy X-ray absorptiometry (DXA) services performed in the nonfacility setting that by January 2010 reduced payments for these services by more than 60% compared with 2006 levels. The objectives of this study were to determine if a temporal association exists between Medicare Physician Fee Schedule changes in office-based DXA reimbursement and attendance at educational conferences for osteoporosis, physicians' perceptions of changes in their medical practices, or national trends in retail prescription medications for osteoporosis in those aged 65 and older. Compared with the 2 yr before the decline in Medicare reimbursement for DXA (2005-2006), attendance at educational meetings for osteoporosis in the US declined in the 2 yr after these cuts (2007-2008) by 6%; declines in attendance were only present in meetings selective for bone densitometry. Survey participants reported changes in DXA services with approximately one-third indicating that they had either decreased the number of DXAs they performed or declined service contracts or hardware/software updates compared with 2005-2006. The number of retail prescriptions for Food and Drug Administration-approved osteoporosis drugs (excluding estrogen compounds and raloxifene) in the age 65 and older population increased by 5.5% in the time period 2007-2008 compared with 2005-2006. However, in the last year of the study (2008), total retail prescriptions for these drugs experienced for the first time over the interval of the study, a decline (1.4%) compared with the previous year. This occurred despite a 2.6% increase in the US population age 65 and older. In conclusion, there were temporal associations noted between Medicare cuts in DXA payments in attendance at educational conferences for bone densitometry, self-report of office-based provision of DXA services in the US, and retail prescriptions for osteoporosis therapies.

Lysophosphatidic acid-activated Cl- current activity in human systemic sclerosis skin fibroblasts

OBJECTIVES

SSc (scleroderma) is an often fatal disease characterized by widespread tissue fibrosis. Fibroblasts play a key role in SSc-associated fibrosis. This study was designed to determine: (i) whether fibroblasts isolated from skin of patients with SSc have increased lysophosphatidic acid-activated Cl- current (IClLPA) activity vs healthy controls; (ii) whether myofibroblast differentiation is involved in SSc skin fibrosis; and (iii) whether SSc fibroblasts have different proliferation rates vs controls.

METHODS

Skin biopsies were taken from involved and uninvolved skin of SSc patients and controls. Whole-cell perforated patch-clamping was used to measure IClLPA activity in fibroblasts isolated and cultured from these biopsies. Western blotting was used to measure α-smooth muscle actin (α-SMA). Proliferation was measured using a colorimetric assay.

RESULTS

Fibroblasts cultured from SSc skin show significantly increased IClLPA activity following LPA exposure compared with control skin fibroblasts. α-SMA protein was significantly increased in cultured SSc skin fibroblasts vs controls. No significant differences in proliferation rates were found.

CONCLUSIONS

Elevated IClLPA activity is a hallmark of SSc skin fibroblasts. Blocking IClLPA activation may be a new therapeutic approach for treating SSc-associated fibrosis.

Elevated serum levels of arachidonoyl-lysophosphatidic acid and sphingosine 1-phosphate in systemic sclerosis

Systemic sclerosis (SSc) is an often fatal disease characterized by autoimmunity and inflammation, leading to widespread vasculopathy and fibrosis. Lysophosphatidic acid (LPA), a bioactive phospholipid in serum, is generated from lysophospholipids secreted from activated platelets in part by the action of lysophospholipase D (lysoPLD). Sphingosine 1-phosphate (S1P), a member of the bioactive lysophospholipid family, is also released from activated platelets. Because activated platelets are a hallmark of SSc, we wanted to determine whether subjects with SSc have altered serum lysophospholipid levels or lysoPLD activity. Lysophospholipid levels were measured using mass spectrometric analysis. LysoPLD activity was determined by quantifying choline released from exogenous lysophosphatidylcholine (LPC). The major results were that serum levels of arachidonoyl (20:4)-LPA and S1P were significantly higher in SSc subjects versus controls. Furthermore, serum LPA:LPC ratios of two different polyunsaturated phospholipid molecular species, and also the ratio of all species combined, were significantly higher in SSc subjects versus controls. No significant differences were found between other lysophospholipid levels or lysoPLD activities. Elevated 20:4 LPA, S1P levels and polyunsaturated LPA:LPC ratios may be markers for and/or play a significant role in the etiology of SSc and may be future pharmacological targets for SSc treatment.

Loop diuretic use and fracture in postmenopausal women: findings from the Women's Health Initiative

BACKGROUND

The relationship of loop diuretics to bone mineral density (BMD), falls, and fractures in postmenopausal women has not been established.

METHODS

We examined whether loop diuretics are associated with changes in BMD, falls, and fractures in women enrolled in the Women's Health Initiative. We included the 133,855 women (3411 users and 130,444 nonusers of loop diuretics) who were enrolled in the WHI from October 29, 1993 to December 31, 1998 and determined incident falls and fractures for a mean of 7.7 years. Women who had BMD measurements at baseline and at year 3 (300 users and 9124 nonusers of loop diuretics) were also examined.

RESULTS

After adjustment for covariates, no significant association was found between ever use of loop diuretics and total (hazard ratio [HR], 1.09; 95% confidence interval [CI], 1.00-1.19), hip (HR, 1.21; 95% CI, 0.91-1.60), and clinical vertebral fractures (HR, 1.17; 95% CI, 0.92-1.48) and falls (1.02; 0.96-1.08). An increased risk was found for other clinical fractures (1.16; 1.01-133) and total fractures (1.16; 1.03-1.31) with more than 3 years' use of loop diuretics. The BMD changes were not associated with loop diuretic use.

CONCLUSIONS

After adjustment for confounding variables, no significant association was found between ever use of loop diuretics and changes in BMD, falls, and fractures. Loop diuretics were used by women in poor health who were already at risk for fractures. However, prolonged use of loop diuretics was associated with higher fracture risk in postmenopausal women.

Fracture risk in men with congestive heart failure risk reduction with spironolactone

OBJECTIVES

The purpose of this study was to determine whether spironolactone use is associated with fractures in men with congestive heart failure (CHF).

BACKGROUND

In rats with aldosteronism, spironolactone preserves skeletal strength. However, in humans, the relationship of spironolactone to fractures is not known.

METHODS

The medical records of all male patients with CHF from 1999 to 2005 treated at the Veterans Affairs Medical Center, Memphis, Tennessee, were reviewed (n = 4,735). Odds ratios with 95% confidence intervals of having a fracture associated with spironolactone use were estimated using conditional logistic regression.

RESULTS

We identified 167 cases with a single-incident fracture and matched these by age and race to 668 control subjects without fractures. After adjustment for covariates, spironolactone use was inversely associated with total fracture (odds ratio: 0.575; 95% confidence interval: 0.346 to 0.955, p = 0.0324).

CONCLUSIONS

The use of spironolactone is inversely associated with fractures in men with CHF.

25-Hydroxyvitamin D, cholesterol, and ultraviolet irradiation

Vitamin D deficiency may have implications for cardiovascular health. The purpose of this study was to determine the relationship of 25-hydroxyvitamin D (25[OH]D) to cholesterol and lipoprotein particles and to determine whether increasing 25(OH)D through ultraviolet (UV) irradiation impacted on these parameters in healthy young men and women. This was a randomized trial of 51 adults exposed to suberythemal doses of whole-body irradiation using UV lamps that emitted UV-A and UV-B radiation, compared with a control group, twice weekly for 12 weeks. 25-Hydroxyvitamin D, cholesterol, and lipoprotein subfractions were measured at baseline and after 12 weeks. There was a significant (P < .03) positive association between 25(OH)D and apolipoprotein A-I (Apo A-I) and lipoprotein A-I (Lp A-I). The ratio of low-density lipoprotein to high-density lipoprotein was significantly (P < or = .044) negatively correlated with 25(OH)D levels. The levels of 25(OH)D increased significantly in the treated compared with control group (P < .05). Overall, there were no significant differences between the treated and control groups in any lipoproteins or apolipoproteins after administration of UV irradiation. Subgroup analysis for Apo A-II confined to those with 25(OH)D insufficiency (25[OH]D <75 nmol/L [30 ng/mL]) revealed decreases in Apo A-II in the treated group and increases in the control group that were statistically significantly different between the groups (P = .026). We found a significant positive correlation between 25(OH)D and Apo A-I and Lp A-I and a significant negative correlation between 25(OH)D and the ratio of low-density lipoprotein to high-density lipoprotein. In those with vitamin D insufficiency, we found small decreases in Apo A-II in the treated relative to the control group. Overall, though, twice weekly exposure to UV radiation resulting in an increase in serum 25(OH)D had no significant impact on lipoprotein composition.

Preliminary findings: 25(OH)D levels and PTH are indicators of rapid bone accrual in pubertal children

OBJECTIVE

The objective of this study was to evaluate the role of serum levels of 25(OH)D and PTH on the accumulation of whole body bone mass in a cohort of children.

METHODS

This was a longitudinal study (1.98 +/- 0.07 y) of sixty-nine children (89% Caucasian, 44% male) enrolled in a calcium supplementation trial. Bone area, bone mineral content (BMC) and density (BMD) of the whole body and radius were assessed using a QDR 2000 (Hologic, Inc) dual energy x-ray absorptiometer. Serum PTH and 25(OH)D were measured using radioimmunoassays.

RESULTS

Vitamin D stores were inversely related gain in bone area (p < 0.002), BMC (p < 0.002) BMD (p < 0.027), as well as to PTH levels (p < 0.0001). Compared to those with adequate vitamin D stores (>34 ng/ml), those who had consistently low vitamin D stores (18 ng/ml) had a 8% larger gain in bone area (p < 0.05); 11% in BMC (p < 0.05) and no differences in gain in BMD; after adjusting for baseline bone measurements, race, gender, season measured, Tanner stage, and calcium intake.

CONCLUSIONS

High normal PTH with low-normal 25(OH)D stores and moderate to high calcium intake may be beneficial to accruing larger bone size and BMC during puberty.