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1.
Osteoporos Int ; 32(6): 1217-1219, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33903925

ABSTRACT

In patients with surgical repair of a low-trauma hip fracture, zoledronic acid (ZA) reduced the risk of subsequent fractures regardless of pretreatment femoral neck and total hip bone mineral density (BMD). INTRODUCTION: Zoledronic acid reduces the risk of subsequent fractures after repair of a hip fracture. It is still unclear whether the benefits in fracture reduction with ZA depend upon hip bone mineral density at the time of fracture. METHODS: We preformed additional post hoc analyses of data from the HORIZON Recurrent Fracture Trial to determine if ZA treatment reduced the risk of new clinical fractures regardless of pretreatment BMD. We modeled femoral neck and total hip BMD as both continuous and dichotomous variables (BMD T-score above and below -2.5). RESULTS: There are no evidence that baseline femoral neck and total hip BMD modified the anti-fracture efficacy of ZA when pretreatment BMD was analyzed as a continuous or a dichotomous variable (interaction p-values > 0.20). The clinical fracture efficacy of ZA was similar among patients with pretreatment femoral neck BMD values above and below -2.5 (relative hazards = 0.60 and 0.67, respectively, interaction p-value = 0.95). A similar result was obtained using pretreatment total hip BMD values (relative hazards = 0.72 and 0.57, respectively, interaction p-value = 0.41). CONCLUSION: There data should provide more comfort in prescribing ZA after surgical repair of a hip fracture, regardless of pretreatment BMD.


Subject(s)
Bone Density Conservation Agents , Hip Fractures , Bone Density , Bone Density Conservation Agents/therapeutic use , Femur Neck/surgery , Hip Fractures/prevention & control , Hip Fractures/surgery , Humans , Zoledronic Acid/therapeutic use
2.
Osteoporos Int ; 32(3): 515-527, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32930851

ABSTRACT

The associations between objective measures of sleep duration and bone outcomes in older men are unknown. No consistent, significant association was identified between sleep duration and bone mineral density (BMD) in the current analysis. However, future research should determine if vitamin D status modifies this relationship. INTRODUCTION: Prior studies, predominantly in women, reported that long and short self-reported sleep duration are associated with lower BMD. Associations between actigraphy-determined sleep duration and BMD or bone turnover markers (BTMs) in older men are unknown. METHODS: Men in The Osteoporotic Fractures in Men (MrOS) Study with wrist actigraphy and concurrent BMD assessment but without comorbidities affecting bone health were included. Sleep duration was considered as a continuous (N = 1926) and dichotomized variable where men were classified as getting the recommended (7-8 h/night; N = 478) or short (< 6 h/night; N = 577) sleep. The cross-sectional association between BMD, BTMs, and sleep duration was examined using a t test or linear regression, where appropriate, in unadjusted and adjusted models. RESULTS: There were no clinically or statistically significant differences in BMD at the L-spine, total hip, or femoral neck between men getting the recommended vs. short sleep duration, using actigraphy or self-reported sleep duration (all p ≥ 0.07). When sleep duration was considered as a continuous variable, femoral neck BMD was higher in men with longer self-reported sleep duration (ß = 0.006 ±0.003, p = 0.02), but this was not significant after further adjustment. In men with low 25OHD (< 20 ng/mL), longer actigraphy-determined sleep duration was associated with higher total hip BMD (ß = 0.016 ± 0.008; p = 0.04). Sleep duration and BTMs were not associated. CONCLUSION: Sleep duration was not associated with hip or L-spine BMD or BTMs in older men. Future research should determine if vitamin D status or other factors modify this relationship.


Subject(s)
Bone Density , Femur Neck , Aged , Cross-Sectional Studies , Female , Humans , Male , Sleep , Vitamin D
3.
Osteoporos Int ; 30(6): 1287-1295, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30809724

ABSTRACT

The paper focuses on the identification of atypical fractures (AFFs). This paper examines the concordance between objective classification and expert subjective review. We believe the paper adds critical information about how to apply the American Society of Bone and Mineral Research (ASBMR) criteria to diagnose AFFs and is of high interest to the field. INTRODUCTION: Assess American Society of Bone and Mineral Research (ASBMR) criteria for identifying atypical femoral fractures (AFFs). METHODS: Two orthopedic surgeons independently evaluated radiographs of 372 fractures, applying ASBMR criteria. We assessed ease of applying ASBMR criteria and whether criteria-based assessment matched qualitative expert assessment. RESULTS: There was up to 27% uncertainty about how to classify specific features. 84% of films were classified similarly for the presence of AFF according to ASBMR criteria; agreement increased to 94% after consensus meeting. Of 37 fractures categorized as AFFs based on ASBMR criteria, 23 (62.2%) were considered AFFs according to expert assessment (not relying on criteria). Only one (0.5%) femoral shaft fracture that did not meet ASBMR criteria was considered an AFF per expert assessment. The number of major ASBMR features present (four vs five) and whether there was periosteal or endosteal thickening ("beaking" or "flaring") played major roles in the discrepancies between ASBMR criteria-based and expert-based determinations. CONCLUSIONS: ASBMR AFF criteria were useful for reviewers but several features were difficult to interpret. Expert assessments did not agree with the ASBMR classification in almost one-third of cases, but rarely identified an AFF when a femoral shaft fracture did not meet ASBMR AFF criteria. Experts identified lateral cortical transverse fracture line and associated new-bone formation along with no or minimal comminution as crucial features necessary for the definition of atypical femoral fractures.


Subject(s)
Femoral Fractures/diagnostic imaging , Advisory Committees , Aged , Bone Density Conservation Agents/adverse effects , Clinical Competence , Diphosphonates/adverse effects , Electronic Health Records , Expert Testimony , Female , Femoral Fractures/chemically induced , Humans , Male , Middle Aged , Observer Variation , Radiography
4.
J Intern Med ; 283(1): 56-72, 2018 01.
Article in English | MEDLINE | ID: mdl-29034571

ABSTRACT

BACKGROUND: Subclinical hyperthyroidism (SHyper) has been associated with increased risk of hip and other fractures, but the linking mechanisms remain unclear. OBJECTIVE: To investigate the association between subclinical thyroid dysfunction and bone loss. METHODS: Individual participant data analysis was performed after a systematic literature search in MEDLINE/EMBASE (1946-2016). Two reviewers independently screened and selected prospective cohorts providing baseline thyroid status and serial bone mineral density (BMD) measurements. We classified thyroid status as euthyroidism (thyroid-stimulating hormone [TSH] 0.45-4.49 mIU/L), SHyper (TSH < 0.45 mIU/L) and subclinical hypothyroidism (SHypo, TSH ≥ 4.50-19.99 mIU/L) both with normal free thyroxine levels. Our primary outcome was annualized percentage BMD change (%ΔBMD) from serial dual X-ray absorptiometry scans of the femoral neck, total hip and lumbar spine, obtained from multivariable regression in a random-effects two-step approach. RESULTS: Amongst 5458 individuals (median age 72 years, 49.1% women) from six prospective cohorts, 451 (8.3%) had SHypo and 284 (5.2%) had SHyper. During 36 569 person-years of follow-up, those with SHyper had a greater annual bone loss at the femoral neck versus euthyroidism: %ΔBMD = -0.18 (95% CI: -0.34, -0.02; I2 = 0%), with a nonstatistically significant pattern at the total hip: %ΔBMD = -0.14 (95% CI: -0.38, 0.10; I2 = 53%), but not at the lumbar spine: %ΔBMD = 0.03 (95% CI: -0.30, 0.36; I2 = 25%); especially participants with TSH < 0.10 mIU/L showed an increased bone loss in the femoral neck (%Δ BMD = -0.59; [95% CI: -0.99, -0.19]) and total hip region (%ΔBMD = -0.46 [95% CI: -1.05, -0.13]). In contrast, SHypo was not associated with bone loss at any site. CONCLUSION: Amongst adults, SHyper was associated with increased femoral neck bone loss, potentially contributing to the increased fracture risk.


Subject(s)
Bone Density , Fractures, Bone , Hyperthyroidism , Hypothyroidism , Aged , Asymptomatic Diseases , Female , Fractures, Bone/etiology , Fractures, Bone/metabolism , Fractures, Bone/prevention & control , Humans , Hyperthyroidism/diagnosis , Hyperthyroidism/epidemiology , Hyperthyroidism/metabolism , Hypothyroidism/diagnosis , Hypothyroidism/epidemiology , Hypothyroidism/metabolism , Male , Risk Factors
5.
Osteoporos Int ; 29(3): 699-705, 2018 03.
Article in English | MEDLINE | ID: mdl-29204959

ABSTRACT

Bone composition evaluated by FTIRI analysis of iliac crest biopsies from post-menopausal women treated with alendronate for 10 years, continuously or alendronate for 5 years, followed by a 5-year alendronate-holiday, only differed with the discontinued biopsies having increased cortical crystallinity and heterogeneity of acid phosphate substitution and decreased trabecular crystallinity heterogeneity. INTRODUCTION: Bisphosphonates (BP) are the most commonly used and effective drugs to prevent fragility fractures; however, concerns exist that prolonged use may lead to adverse events. Recent recommendations suggest consideration of a BP "holiday" in individuals taking long-term BP therapy not at high risk of fracture. Data supporting or refuting this recommendation based on bone quality are limited. We hypothesized that a "holiday" of 5 years would cause no major bone compositional changes. METHODS: We analyzed the 31 available biopsies from the FLEX-Long-term Extension of FIT (Fracture Intervention Trial) using Fourier transform infrared imaging (FTIRI). Biopsies from two groups of post-menopausal women, a "Continuously treated group" (N = 16) receiving alendronate for ~ 10 years and a "Discontinued group" (N = 15), alendronate treated for 5 years taking no antiresorptive medication during the following 5 years. Iliac crest bone biopsies were provided at 10 years. RESULTS: Key FTIRI parameters, mineral-to-matrix ratio, carbonate-to-phosphate ratio, acid phosphate substitution, and collagen cross-link ratio as well as heterogeneity of these parameters were similar for Continuously treated and Discontinued groups in age-adjusted models. The Discontinued group had 2% greater cortical crystallinity (p = 0.01), 31% greater cortical acid phosphate heterogeneity (p = 0.02), and 24% lower trabecular crystallinity heterogeneity (p = 0.02). CONCLUSIONS: Discontinuation of alendronate for 5 years did not affect key FTIRI parameters, supporting the hypothesis that discontinuation would have little impact on bone composition. Modest differences were observed in three parameters that are not likely to affect bone mechanical properties. These preliminary data suggest that a 5-year BP holiday is not harmful to bone composition.


Subject(s)
Alendronate/administration & dosage , Bone Density Conservation Agents/administration & dosage , Osteoporosis, Postmenopausal/drug therapy , Aged , Alendronate/pharmacology , Alendronate/therapeutic use , Biopsy , Bone Density/drug effects , Bone Density Conservation Agents/pharmacology , Bone Density Conservation Agents/therapeutic use , Double-Blind Method , Female , Follow-Up Studies , Humans , Ilium/drug effects , Ilium/pathology , Osteoporosis, Postmenopausal/pathology , Osteoporosis, Postmenopausal/physiopathology , Osteoporotic Fractures/prevention & control , Withholding Treatment
6.
Osteoporos Int ; 29(1): 49-59, 2018 01.
Article in English | MEDLINE | ID: mdl-29090329

ABSTRACT

Among older men, characteristics that predict longitudinal changes in trabecular bone score (TBS) are different from characteristics that predict changes in bone mineral density (BMD). Most notably, weight loss is strongly associated with concomitant loss in BMD but with concomitant increases in TBS, when measured on Hologic densitometers. INTRODUCTION: Our objective was to compare and contrast predictors of changes in TBS, total hip BMD, and lumbar spine BMD. METHODS: Our study population was 3969 Osteoporotic Fractures in Men (MrOS) cohort participants (mean age 72.8 years) with repeat measures of TBS, lumbar spine and total hip BMD, body mass index (BMI) less than 37 kg/m2, and no use of bisphosphonate or glucocorticoid medications. TBS was scored (Med-Imaps Software version 2.1) and BMD measured on Hologic densitometers. RESULTS: One thousand four hundred forty-four men had a TBS decrease > 0.04 units (estimated least significant change for TBS), 795 men had a TBS increase > 0.04 units, and 1730 men had TBS change ≤ 0.04 units over mean follow-up of 4.6 years. Older age was not associated with TBS change, but was associated with greater decline in lumbar spine and total hip BMD. Compared to stable weight, > 10% weight loss was strongly associated with an increase in TBS [effect size = 1.24 (95% CI 1.12, 1.36)] and strongly associated with a decrease in total hip BMD [- 1.16 (95% CI - 1.19, - 1.03)]. Other predictors discordant for longitudinal changes of TBS and BMD included baseline BMI, walk speed, and ACE inhibitor use. CONCLUSIONS: Predictors of changes in TBS are different from predictors of changes in lumbar spine and total hip BMD. At least when assessed on Hologic densitometers, weight loss is associated with subsequent declines in spine and total hip BMD but subsequent increase in TBS. Faster walk speed may protect against loss of hip BMD, but is not associated with longitudinal changes of TBS.


Subject(s)
Bone Density/physiology , Cancellous Bone/physiopathology , Osteoporotic Fractures/physiopathology , Absorptiometry, Photon/methods , Aged , Body Mass Index , Cancellous Bone/diagnostic imaging , Follow-Up Studies , Hip Joint/physiopathology , Humans , Lumbar Vertebrae/physiopathology , Male , Osteoporosis/diagnostic imaging , Osteoporosis/physiopathology , Osteoporotic Fractures/diagnostic imaging , Prospective Studies , Spinal Fractures/diagnostic imaging , Spinal Fractures/physiopathology , Weight Loss/physiology
7.
Osteoporos Int ; 29(1): 69-77, 2018 01.
Article in English | MEDLINE | ID: mdl-29063213

ABSTRACT

Dairy protein but not plant protein was associated with bone strength of the radius and tibia in older men. These results are consistent with previous results in women and support similar findings related to fracture outcomes. Bone strength differences were largely due to thickness and area of the bone cortex. INTRODUCTION: Our objective was to determine the association of protein intake by source (dairy, non-dairy animal, plant) with bone strength and bone microarchitecture among older men. METHODS: We used data from 1016 men (mean 84.3 years) who attended the Year 14 exam of the Osteoporotic Fractures in Men (MrOS) study, completed a food frequency questionnaire (500-5000 kcal/day), were not taking androgen or androgen agonists, and had high-resolution peripheral quantitative computed tomography (HR-pQCT) scans of the distal radius and distal or diaphyseal tibia. Protein was expressed as percentage of total energy intake (TEI); mean ± SD for TEI = 1548 ± 607 kcal/day and for total protein = 16.2 ± 2.9%TEI. We used linear regression with standardized HR-pQCT parameters as dependent variables and adjusted for age, limb length, center, education, race/ethnicity, marital status, smoking, alcohol intake, physical activity level, corticosteroids use, supplement use (calcium and vitamin D), and osteoporosis medications. RESULTS: Higher dairy protein intake was associated with higher estimated failure load at the distal radius and distal tibia [radius effect size = 0.17 (95% CI 0.07, 0.27), tibia effect size = 0.13 (95% CI 0.03, 0.23)], while higher non-dairy animal protein was associated with higher failure load at only the distal radius. Plant protein intake was not associated with failure load at any site. CONCLUSION: The association between protein intake and bone strength varied by source of protein. These results support a link between dairy protein intake and skeletal health, but an intervention study is needed to evaluate causality.


Subject(s)
Bone Density/drug effects , Dietary Proteins/administration & dosage , Radius/physiology , Tibia/physiology , Aged , Aged, 80 and over , Biomechanical Phenomena , Cross-Sectional Studies , Dietary Proteins/pharmacology , Feeding Behavior , Humans , Male , Milk Proteins/administration & dosage , Milk Proteins/pharmacology , Plant Proteins, Dietary/administration & dosage , Plant Proteins, Dietary/pharmacology , Tomography, X-Ray Computed/methods
8.
J Clin Pharm Ther ; 42(2): 228-233, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28111765

ABSTRACT

WHAT IS KNOWN AND OBJECTIVE: There are few studies examining both drug-drug and drug-disease interactions in older adults. Therefore, the objective of this study was to describe the prevalence of potential drug-drug and drug-disease interactions and associated factors in community-dwelling older adults. METHODS: This cross-sectional study included 3055 adults aged 70-79 without mobility limitations at their baseline visit in the Health Aging and Body Composition Study conducted in the communities of Pittsburgh PA and Memphis TN, USA. The outcome factors were potential drug-drug and drug-disease interactions as per the application of explicit criteria drawn from a number of sources to self-reported prescription and non-prescription medication use. RESULTS: Over one-third of participants had at least one type of interaction. Approximately one quarter (25·1%) had evidence of had one or more drug-drug interactions. Nearly 10·7% of the participants had a drug-drug interaction that involved a non-prescription medication. % The most common drug-drug interaction was non-steroidal anti-inflammatory drugs (NSAIDs) affecting antihypertensives. Additionally, 16·0% had a potential drug-disease interaction with 3·7% participants having one involving non-prescription medications. The most common drug-disease interaction was aspirin/NSAID use in those with history of peptic ulcer disease without gastroprotection. Over one-third (34·0%) had at least one type of drug interaction. Each prescription medication increased the odds of having at least one type of drug interaction by 35-40% [drug-drug interaction adjusted odds ratio (AOR) = 1·35, 95% confidence interval (CI) = 1·27-1·42; drug-disease interaction AOR = 1·30; CI = 1·21-1·40; and both AOR = 1·45; CI = 1·34-1·57]. A prior hospitalization increased the odds of having at least one type of drug interaction by 49-84% compared with those not hospitalized (drug-drug interaction AOR = 1·49, 95% CI = 1·11-2·01; drug-disease interaction AOR = 1·69, CI = 1·15-2·49; and both AOR = 1·84, CI = 1·20-2·84). WHAT IS NEW AND CONCLUSION: Drug interactions are common among community-dwelling older adults and are associated with the number of medications and hospitalization in the previous year. Longitudinal studies are needed to evaluate the impact of drug interactions on health-related outcomes.


Subject(s)
Drug Interactions , Aged , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Cross-Sectional Studies , Female , Humans , Male
9.
Osteoporos Int ; 27(1): 331-8, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26458388

ABSTRACT

UNLABELLED: We investigated the value of routine laboratory testing for identifying underlying causes in older men diagnosed with osteoporosis. Most osteoporotic and nonosteoporotic men had ≥1 laboratory abnormality. Few individual laboratory abnormalities were more common in osteoporotic men. The benefit of routine laboratory testing in older osteoporotic men may be low. INTRODUCTION: To evaluate the utility of recommended laboratory testing to identify secondary causes in older men with osteoporosis, we examined prevalence of laboratory abnormalities in older men with and without osteoporosis. METHODS: One thousand five hundred seventy-two men aged ≥65 years in the Osteoporotic Fractures in Men study completed bone mineral density (BMD) testing and a battery of laboratory measures, including serum calcium, phosphorus, alkaline phosphatase, parathyroid hormone (PTH), thyroid-stimulating hormone (TSH), 25-OH vitamin D, total testosterone, spot urine calcium/creatinine ratio, spot urine albumin/creatinine ratio, creatinine-derived estimated glomerular filtration rate, 24-h urine calcium, and 24-h urine free cortisol. Using cross-sectional analyses, we calculated prevalence ratios (PRs) and 95 % confidence intervals (CI) for the association of any and specific laboratory abnormalities with osteoporosis and the number of men with osteoporosis needed to test to identify one additional laboratory abnormality compared to testing men without osteoporosis. RESULTS: Approximately 60 % of men had ≥1 laboratory abnormality in both men with and without osteoporosis. Among individual tests, only vitamin D insufficiency (PR, 1.13; 95 % CI, 1.05-1.22) and high alkaline phosphatase (PR, 3.05; 95 % CI, 1.52-6.11) were more likely in men with osteoporosis. Hypercortisolism and hyperthyroidism were uncommon and not significantly more frequent in men with osteoporosis. No osteoporotic men had hypercalciuria. CONCLUSIONS: Though most of these older men had ≥1 laboratory abnormality, few routinely recommended individual tests were more common in men with osteoporosis than in those without osteoporosis. Possibly excepting vitamin D and alkaline phosphatase, benefit of routine laboratory testing to identify possible secondary causes in older osteoporotic men appears low. Results may not be generalizable to younger men or to older men in whom history and exam findings raise clinical suspicion for a secondary cause of osteoporosis.


Subject(s)
Diagnostic Tests, Routine/methods , Osteoporosis/etiology , Absorptiometry, Photon/methods , Aged , Aged, 80 and over , Biomarkers/blood , Biomarkers/urine , Bone Density/physiology , Cross-Sectional Studies , Humans , Male , Osteoporosis/physiopathology , Prospective Studies , Unnecessary Procedures , Vitamin D Deficiency/complications , Vitamin D Deficiency/diagnosis
11.
Osteoporos Int ; 23(3): 887-99, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21625880

ABSTRACT

UNLABELLED: To examine the association between renal function and fracture in multiethnic women, we studied postmenopausal women enrolled in the Women's Health Initiative. Postmenopausal White women with mild renal dysfunction were at increased risk of nonvertebral fracture; this association was at least partially explained by effects of renal dysfunction on chronic inflammation. Reduced renal function appeared to increase fracture risk among Black women, but there was little evidence to support this association among other racial/ethnic groups. INTRODUCTION: The purpose of this study was to determine whether renal function is associated with fracture risk within racial/ethnic groups. METHODS: A nested case-control study was conducted among 93,673 postmenopausal women; incident nonvertebral fractures were identified in 362 Black, 183 Hispanic, 110 Asian, and 45 American-Indian women. A random sample of 395 White women with incident nonvertebral fracture was chosen. One nonfracture control for each case was selected (matched on age, race/ethnicity, and blood draw date). Cystatin C levels were measured using baseline serum, and estimated glomerular filtration rate calculated (eGFR(cys-c)). RESULTS: Each 1 SD increase in cystatin C was associated with a 1.2-fold increased risk of fracture among White women (adjusted odds ratios [OR], 1.23; 95% confidence intervals [CI], 1.04-1.46). The OR of fracture was 1.16 (95% CI, 0.85-1.58) among women with eGFR(cys-c) 60-90 mL/min/1.73 m(2) and 2.46 (95% CI, 1.16-5.21) among those with eGFR(cys-c) <60 mL/min/1.73 m(2) compared to the reference group (eGFR(cys-c) >90 mL/min/1.73 m(2)) (p trend = 0.05). The association was reduced after adjustment for cytokine TNFα soluble receptors (OR, 1.62; 95% CI, 0.59-4.46 for eGFR(cys-c) <60 mL/min/1.73 m(2)). Among Blacks, there was an association between cystatin C and fracture risk (OR per 1 SD increase, 1.15; 95% CI, 1.00-1.32); after adjustment, this association was only modestly attenuated, but no longer statistically significant. There was no evidence of significant associations among Hispanic, Asian, or American-Indian women. CONCLUSION: Postmenopausal White women with mild renal dysfunction are at increased risk of nonvertebral fracture. Effects of renal function on chronic inflammation may mediate this association. Reduced renal function may increase fracture risk among Black women, but there was little evidence to support this association among other racial/ethnic groups.


Subject(s)
Fractures, Bone/etiology , Renal Insufficiency, Chronic/complications , Aged , Biomarkers/blood , Case-Control Studies , Cystatin C/blood , Female , Fractures, Bone/blood , Fractures, Bone/ethnology , Glomerular Filtration Rate , Humans , Inflammation Mediators/blood , Middle Aged , Postmenopause/blood , Postmenopause/ethnology , Postmenopause/physiology , Prospective Studies , Renal Insufficiency, Chronic/blood , Renal Insufficiency, Chronic/ethnology , Risk Assessment/methods , United States/epidemiology
12.
Osteoporos Int ; 21(3): 439-45, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19506793

ABSTRACT

SUMMARY: To determine the laboratory reproducibility of urine N-telopeptide and serum bone-specific alkaline phosphatase measurements, we sent identical specimens to six US commercial labs over an 8-month period. Longitudinal and within-run laboratory reproducibility varied substantially. Efforts to improve the reproducibility of these tests are needed. INTRODUCTION: We assessed the laboratory reproducibility of urine N-telopeptide (NTX) and serum bone-specific alkaline phosphatase (BAP). METHODS: Serum and urine were collected from five postmenopausal women, pooled, divided into identical aliquots, and frozen. To evaluate longitudinal reproducibility, identical specimens were sent to six US commercial labs on five dates over an 8-month period. To evaluate within-run reproducibility, on the fifth date, each lab was sent five identical specimens. Labs were unaware of the investigation. RESULTS: Longitudinal coefficients of variation (CVs) ranged from 5.4% to 37.6% for NTX and from 3.1% to 23.6% for BAP. Within-run CVs ranged from 1.5% to 17.2% for NTX. Compared to the Osteomark NTX assay, the Vitros ECi NTX assay had significantly higher longitudinal reproducibility (mean CV 7.2% vs. 30.3%, p < 0.0005) and within-run reproducibility (mean CV 3.5% vs. 12.7%, p < 0.0005). CONCLUSIONS: Reproducibility of urine NTX and serum BAP varies substantially across US labs.


Subject(s)
Alkaline Phosphatase/blood , Bone Remodeling/physiology , Collagen Type I/urine , Peptides/urine , Aged , Biomarkers/blood , Biomarkers/urine , Clinical Laboratory Techniques/standards , Female , Humans , Middle Aged , Postmenopause/blood , Postmenopause/urine , Reference Values , Reproducibility of Results
13.
Osteoporos Int ; 21(1): 167-77, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19436934

ABSTRACT

INTRODUCTION: The purpose of the study was to test the hypothesis that the reduction in fractures with hormone therapy (HT) is greater in women with lower estradiol levels. METHODS: We conducted a nested case-control study within the Women's Health Initiative HT Trials. The sample included 231 hip fracture case-control pairs and a random sample of 519 all fracture case-control pairs. Cases and controls were matched for age, ethnicity, randomization date, fracture history, and hysterectomy status. Hormones were measured prior to randomization. Incident cases of fracture were identified over an average follow-up of 6.53 years. RESULTS: There was no evidence that the effect of HT on fracture differed by baseline estradiol (E2) or sex hormone binding globulin (SHBG). Across all quartiles of E2 and SHBG, women randomized to HT had about a 50% lower risk of fracture, including hip fracture, compared to placebo. CONCLUSION: The effect of HT on fracture reduction is independent of estradiol and SHBG levels.


Subject(s)
Estradiol/blood , Estrogen Replacement Therapy , Osteoporotic Fractures/prevention & control , Aged , Biomarkers/blood , Epidemiologic Methods , Female , Hip Fractures/blood , Hip Fractures/prevention & control , Humans , Hysterectomy , Middle Aged , Osteoporosis, Postmenopausal/blood , Osteoporosis, Postmenopausal/drug therapy , Osteoporotic Fractures/blood , Sex Hormone-Binding Globulin/metabolism , Treatment Outcome
14.
J Hum Hypertens ; 21(8): 673-82, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17429448

ABSTRACT

The role of renin-angiotensin system (RAS) genes on the risk of lower extremity arterial disease (LEAD) in elderly people remains unclear. We assessed the relationship of genetic polymorphisms in RAS: G-6A, T174M and M235T of the angiotensinogen (AGT) gene, and the angiotensin-converting enzyme insertion/deletion (ACE_I/D) variant to the risk of LEAD in the Health, Aging and Body Composition (Health ABC) Study. This analysis included 1228 black and 1306 white men and women whose age ranged between 70 and 79 years at the study enrollment. LEAD was defined as ankle-arm index (AAI) <0.9. Genotype-phenotype associations were estimated by regression analyses with and without adjustment for established cardiovascular disease (CVD) risk factors. The proportion of LEAD was significantly higher in black (21.1%) than that in white elderly people (10.1%, P<0.0001). The distribution of AGT polymorphisms was also significantly different between black and white participants. There was no statistically significant association between the selected RAS genetic variants and LEAD after adjustment for age, antihypertensive medications, lipid-lowering medication, pack-year smoking, body mass index, low-density lipoprotein cholesterol, and prevalent diabetes and coronary heart disease. However, A-T haplotype of G-6A and M235T interacting with homozygous ACE_II (beta=-1.07, P=0.006) and with ACE inhibitors (beta=-1.03, P=0.01) significantly decreased the risk of LEAD in white but not in black participants after adjustment for the selected CVD risk factors. In conclusion, the study observed a gene-gene and gene-drug interaction for LEAD in the white elderly.


Subject(s)
Angiotensinogen/genetics , Peptidyl-Dipeptidase A/genetics , Peripheral Vascular Diseases/genetics , Polymorphism, Genetic , Aged , Black People , Body Composition , Female , Genotype , Haplotypes , Humans , Male , Peripheral Vascular Diseases/ethnology , Phenotype , White People
15.
J Clin Endocrinol Metab ; 91(4): 1370-5, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16449339

ABSTRACT

CONTEXT: Treatment of osteoporotic women with PTH increases biochemical markers of bone turnover, increases axial bone mineral density (BMD), and reduces fracture risk. OBJECTIVE: Our objective was to determine the relationship between levels of baseline turnover before PTH therapy and short-term changes in turnover during PTH therapy and subsequent changes in areal and volumetric BMD. DESIGN AND SETTING: We conducted a randomized, placebo-controlled trial at four academic centers. PATIENTS: Patients included 238 postmenopausal women with low hip or spine BMD. INTERVENTION: Subjects were randomized to sc PTH (1-84), 100 mug/d (119 women), for 1 yr. MAIN OUTCOME MEASURE: Bone turnover markers were measured in fasting blood samples collected before therapy and after 1 and 3 months. Areal and volumetric BMD at the spine and hip were assessed by dual-energy x-ray absorptiometry and quantitative computed tomography (QCT) after 1 yr of therapy. RESULTS: Among women treated with PTH alone, the relationships between baseline turnover and 1-yr changes in dual-energy x-ray absorptiometry and QCT BMD were inconsistent. Greater 1- and 3-month increases in turnover, particularly the formation marker N-propeptide of type I collagen, were associated with greater increases in areal BMD. When volumetric hip and spine BMD were assessed by QCT, greater short-term increases in turnover were even more positively associated with 1-yr increases in BMD. Each sd increase in the 3-month change of N-propeptide of type I collagen was associated with an a 21% greater increase in QCT spine trabecular BMD. CONCLUSIONS: Greater short-term changes in turnover with PTH therapy are associated with greater 1-yr increases in spine and hip BMD among postmenopausal osteoporotic women.


Subject(s)
Bone Density/drug effects , Bone and Bones/metabolism , Osteoporosis, Postmenopausal/drug therapy , Osteoporosis, Postmenopausal/metabolism , Parathyroid Hormone/pharmacology , Parathyroid Hormone/therapeutic use , Absorptiometry, Photon , Aged , Aged, 80 and over , Alendronate/therapeutic use , Biomarkers , Bone Density Conservation Agents/therapeutic use , Bone and Bones/drug effects , Female , Humans , Middle Aged
16.
J Natl Cancer Inst ; 93(12): 930-6, 2001 Jun 20.
Article in English | MEDLINE | ID: mdl-11416114

ABSTRACT

BACKGROUND: Older women with low bone mineral density (BMD) have a decreased incidence of breast cancer. It is not known whether this association is confined to early-stage, slow-growing tumors. METHODS: We prospectively studied 8905 women who were 65 years of age or older during the period from 1986 through 1988 and had no history of breast cancer. At study entry, we used single-photon absorptiometry to measure each woman's BMD at three skeletal sites: the wrist, forearm, and heel. The women were followed for a mean of 6.5 years for the occurrence of breast cancer. All statistical tests were two-sided. RESULTS: During 57 516 person-years of follow-up, 315 women developed primary invasive or in situ breast cancer. Multivariate analyses that adjusted for age, obesity, and other covariates revealed that the risk of breast cancer for women in the highest quartile of BMD for all three skeletal sites was 2.7 (95% confidence interval [CI] = 1.4 to 5.3) times greater than that for women in the lowest quartile at all three skeletal sites. The magnitude of increased risk associated with high BMD differed by the stage of disease at diagnosis and was greater for more advanced tumors (relative risk [RR] for TNM [i.e., tumor-lymph node-metastasis] stage II or higher tumors = 5.6; 95% CI = 1.2 to 27.4) than for early-stage disease (RR for in situ/TNM stage I tumors = 2.2; 95% CI = 1.0 to 4.8). CONCLUSIONS: Elderly women with high BMD have an increased risk of breast cancer, especially advanced cancer, compared with women with low BMD. These findings suggest an association between osteoporosis and invasive breast cancer, two of the most prevalent conditions affecting an older woman's health.


Subject(s)
Bone Density , Breast Neoplasms/epidemiology , Absorptiometry, Photon , Age Factors , Aged , Body Height , Body Mass Index , Breast Neoplasms/diagnosis , Breast Neoplasms/pathology , Breast Neoplasms/physiopathology , Female , Humans , Incidence , Longitudinal Studies , Menarche , Menopause , Multivariate Analysis , Neoplasm Staging , Obesity/epidemiology , Osteoporosis , Prospective Studies , Risk Assessment , Risk Factors , Time Factors , United States/epidemiology
17.
Am J Med ; 129(2): 221.e1-10, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26524708

ABSTRACT

Vertebral fractures are common and can result in acute and chronic pain, decreases in quality of life, and diminished lifespan. The identification of vertebral fractures is important because they are robust predictors of future fractures. The majority of vertebral fractures do not come to clinical attention. Numerous modalities exist for visualizing suspected vertebral fracture. Although differing definitions of vertebral fracture may present challenges in comparing data between different investigations, at least 1 in 5 men and women aged >50 years have one or more vertebral fractures. There is clinical guidance to target spine imaging to individuals with a high probability of vertebral fracture. Radiology reports of vertebral fracture need to clearly state that the patient has a "fracture," with further pertinent details such as the number, recency, and severity of vertebral fracture, each of which is associated with risk of future fractures. Patients with vertebral fracture should be considered for antifracture therapy. Physical and pharmacologic modalities of pain control and exercises or physiotherapy to maintain spinal movement and strength are important components in the care of vertebral fracture patients.


Subject(s)
Osteoporotic Fractures , Spinal Fractures , Aged , Back Pain/etiology , Canada/epidemiology , Female , Humans , Male , Middle Aged , Osteoporotic Fractures/complications , Osteoporotic Fractures/diagnostic imaging , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/prevention & control , Prevalence , Quality of Life , Radiography , Risk Factors , Spinal Fractures/complications , Spinal Fractures/diagnostic imaging , Spinal Fractures/epidemiology , Spinal Fractures/prevention & control
18.
QJM ; 98(8): 575-9, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15983022

ABSTRACT

BACKGROUND: Fractures and atherosclerosis are common in patients with renal failure; this may be due to hyperhomocysteinemia. AIM: To examine the relationships between fractures, vascular calcification and homocysteine levels in haemodialysis patients. DESIGN: Cross-sectional survey. METHODS: We enrolled 37 men and 15 women who had been on haemodialysis for at least 1 year. We identified prevalent spine fractures by radiographs. Non-spine fractures were identified by self-report and confirmed by review of radiographs or radiology reports. We classified the presence and severity of lumbar aortic calcifications with lateral lumbar radiographs. We measured serum homocysteine in all subjects within 30 days of study entry. RESULTS: After adjusting for age and weight, increased levels of homocysteine were associated with an increased risk fracture (OR per mmol/l increase in homocysteine 1.6, 95%CI 1.2-2.0), as was the presence of aortic calcification (OR 1.6, 95%CI 1.2-2.1). Homocysteine and lumbar aortic calcification were highly correlated (r = 0.86). DISCUSSION: Hyperhomocysteinaemia may explain the relationship between fractures and atherosclerosis in patients with renal failure.


Subject(s)
Calcinosis/etiology , Fractures, Bone/etiology , Homocysteine/blood , Hyperhomocysteinemia/complications , Kidney Failure, Chronic/complications , Vascular Diseases/etiology , Aged , Cross-Sectional Studies , Female , Humans , Hyperhomocysteinemia/blood , Hyperhomocysteinemia/pathology , Kidney Failure, Chronic/therapy , Male , Middle Aged , Renal Dialysis , Spinal Fractures/etiology
19.
J Clin Densitom ; 8(3): 362-8, 2005.
Article in English | MEDLINE | ID: mdl-16055969

ABSTRACT

Diagnosis of vertebral fracture is critical for management of osteoporosis, as existence of such deformities substantially increases the risk of subsequent fracture. Thus, accurate and precise techniques allowing detection of such deformities are essential to clinicians. So far, this detection has been performed by spinal lateral X-rays. More advanced techniques have recently been developed, based on dual energy X-ray absorptiometry (DXA). This review describes these different techniques and discusses the effectiveness of the DXA technique to assess vertebral deformities compared to X-ray. The use of DXA detection of vertebral fracture for clinical practice and clinical trials is discussed. Specifically, vertebral morphometry using DXA provides an excellent specificity, with moderate sensitivity. The major limitation of the DXA vertebral assessment is the poor quality of images of thoracic vertebrae. The clinical utility of vertebral morphometry using densitometry may help screening patients with vertebral fracture, but technological improvements are necessary to improve image quality.


Subject(s)
Absorptiometry, Photon , Bone Density , Lumbar Vertebrae/injuries , Spinal Fractures/diagnostic imaging , Thoracic Vertebrae/injuries , Humans , Lumbar Vertebrae/diagnostic imaging , Osteoporosis/complications , Osteoporosis/diagnostic imaging , Reproducibility of Results , Sensitivity and Specificity , Spinal Fractures/etiology , Thoracic Vertebrae/diagnostic imaging
20.
Arch Intern Med ; 156(20): 2333-7, 1996 Nov 11.
Article in English | MEDLINE | ID: mdl-8911240

ABSTRACT

BACKGROUND: The appropriate use of specific thyroid function tests to detect thyroid dysfunction remains controversial; some experts recommend both a sensitive thyrotropin (sTSH) test and a free thyroxine (FT4) test, while others recommend an sTSH test alone. OBJECTIVE: To determine how often sTSH and FT4 tests are ordered simultaneously, how often the results are discordant, and under what circumstances a single test of thyroid function may be sufficient to rule out thyroid dysfunction. METHODS: Retrospective descriptive study of all sTSH and FT4 tests performed on adult outpatients during a 6-month period. If both sTSH and FT4 tests were performed on a single serum specimen, the results were classified as concordant (both tests indicating hypothyroidism, hyperthyroidism, or euthyroidism) or discordant. Chart review was performed on patients with normal sTSH results and abnormal FT4 results. RESULTS: A total of 6551 sTSH and 3518 FT4 tests were performed during the study period. Both sTSH and FT4 tests were ordered together on 3143 specimens (48% and 89% of the total number of sTSH and FT4 tests ordered, respectively) from 2629 patients. Of the sTSH results, 69.8% were within the normal range, and 92.7% of the FT4 results were normal. The concordance between sTSH and FT4 results was 74.3%. Among the 1835 specimens with normal sTSH results, FT4 level was low in 11 patients (0.6%; 95% confidence interval, 0.3%-0.9%) and high in 24 (1.3%; 95% confidence interval, 0.8%-1.8%). Chart review did not disclose any instances when an abnormal FT4 results contributed to the treatment of an individual with a normal sTSH result. CONCLUSIONS: The sTSH test alone, and not the combination of sTSH and FT4 tests, should be ordered in most outpatients. An FT4 test should not be routinely ordered if the sTSH result is normal; at our institution this approach would obviate the need for at least half of the FT4 tests performed each year.


Subject(s)
Mass Screening/methods , Thyroid Diseases/prevention & control , Thyrotropin/blood , Thyroxine/blood , Adult , Aged , Ambulatory Care , Bias , Humans , Medical Audit , Middle Aged , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity , Thyroid Diseases/blood
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