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Ensrud KE, Barbour K, Canales MT, Danielson ME, Boudreau RM, Bauer DC, Lacroix AZ, Ishani A, Jackson RD, Robbins JA, Cauley JA. Renal function and nonvertebral fracture risk in multiethnic women: the Women's Health Initiative (WHI). Osteoporos Int 2012; 23:887-99. [PMID: 21625880 PMCID: PMC3643305 DOI: 10.1007/s00198-011-1667-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 04/14/2011] [Indexed: 01/22/2023]
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.
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Marcum ZA, Perera S, Donohue JM, Boudreau RM, Newman AB, Ruby CM, Studenski SA, Kwoh CK, Simonsick EM, Bauer DC, Satterfield S, Hanlon JT. Analgesic use for knee and hip osteoarthritis in community-dwelling elders. PAIN MEDICINE 2011; 12:1628-36. [PMID: 21992521 DOI: 10.1111/j.1526-4637.2011.01249.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To examine the prevalence and correlates of non-opioid and opioid analgesic use and descriptively evaluate potential undertreatment in a sample of community-dwelling elders with symptomatic knee and/or hip osteoarthritis (OA). DESIGN Cross-sectional. SETTING Health, Aging, and Body Composition Study. PATIENTS Six hundred and fifty-two participants attending the year 6 visit (2002-03) with symptomatic knee and/or hip OA. OUTCOME MEASURES Analgesic use was defined as taking ≥1 non-opioid and/or ≥1 opioid receptor agonist. Non-opioid and opioid doses were standardized across all agents by dividing the daily dose used by the minimum effective analgesic daily dose. Inadequate pain control was defined as severe/extreme OA pain in the past 30 days from a modified Western Ontario and McMaster Universities Osteoarthritis Index. RESULTS Just over half (51.4%) reported taking at least one non-opioid analgesic and approximately 10% was taking an opioid, most (88.5%) of whom also took a non-opioid. One in five participants (19.3%) had inadequate pain control, 39% of whom were using <1 standardized daily dose of either a non-opioid or opioid analgesic. In adjusted analyses, severe/extreme OA pain was significantly associated with both non-opioid (adjusted odds ratio [AOR] = 2.44; 95% confidence interval [95% CI] = 1.49-3.99) and opioid (AOR = 2.64; 95% CI = 1.26-5.53) use. CONCLUSIONS Although older adults with severe/extreme knee and/or hip OA pain are more likely to take analgesics than those with less severe pain, a sizable proportion takes less than therapeutic doses and thus may be undertreated. Further research is needed to examine barriers to optimal analgesic use.
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Manini TM, Patel KV, Bauer DC, Ziv E, Schoeller DA, Mackey DC, Li R, Newman AB, Nalls M, Zmuda JM, Harris TB. European ancestry and resting metabolic rate in older African Americans. Eur J Clin Nutr 2011; 65:663-7. [PMID: 21468093 DOI: 10.1038/ejcn.2011.22] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND/OBJECTIVES Resting metabolic rate (RMR) contributes 60-80% of total energy expenditure and is consistently lower in populations of African descent compared with populations of European populations. Determination of European ancestry (EA) through single nucleotide polymorphism (SNP) analysis would provide an initial step for identifying genetic associations that contribute to low RMR. We sought to evaluate the association between RMR and EA in African Americans. SUBJECTS/METHODS RMR was measured by indirect calorimetry in 141 African American men and women (aged 74.7±3.0 years) enrolled in a substudy of the Health, Aging and Body Composition Study. Ancestry informative markers were used to estimate individual percent EA. Multivariate regression was used to assess the association between RMR and EA after adjustments for soft tissue fat-free mass (STFFM), fat mass, age, study site, physical activity level and sex. RESULTS Mean EA was 23.8±16% (range: 0.1-70.7%) and there were no differences by sex. Following adjustments, each percent EA was associated with a 1.6 kcal/day (95% Confidence interval: 0.42, 2.7 kcal/day) higher RMR (P=0.008). This equates to a 160 kcal/day lower RMR in a population of completely African ancestry, with one of completely European ancestry. Additional adjustment for trunk STFFM that partially accounts for high-metabolic rate organs did not affect this association. CONCLUSIONS EA in African Americans is strongly associated with higher RMR. The data suggest that population differences in RMR may be due to genetic variants.
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Lee JS, Buzková P, Fink HA, Vu J, Carbone L, Chen Z, Cauley J, Bauer DC, Cappola AR, Robbins J. Subclinical thyroid dysfunction and incident hip fracture in older adults. ACTA ACUST UNITED AC 2010; 170:1876-83. [PMID: 21098345 DOI: 10.1001/archinternmed.2010.424] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Subclinical thyroid dysfunction is common in older adults and affects bone metabolism, but its effects on fracture risk have not been reported. We sought to determine prospectively whether older men and women with subclinical hyperthyroidism or hypothyroidism have an increased risk of hip fracture. METHODS Prospective cohort of 3567 US community-dwelling adults, 65 years or older, with biochemically defined subclinical thyroid dysfunction or euthyroidism was enrolled from June 10, 1989, through May 30, 1990, and followed up through 2004. Main outcome measures included incidence and hazard ratios (HRs), with 95% confidence intervals (CIs), of confirmed incident hip fractures for groups with subclinical hypothyroidism, subclinical hyperthyroidism, and euthyroidism as defined at baseline. RESULTS During 39 952 person-years (median follow-up, 13 years), hip fracture incidence (per 1000 men-years) was 13.65 in men with subclinical hyperthyroidism (n = 29) and 10.27 in men with subclinical hypothyroidism (n = 184), both greater than 5.0 in men with euthyroidism (n = 1159). Men with subclinical hypothyroidism had a multivariable-adjusted HR of 2.31 (95% CI, 1.25-4.27); those with subclinical hyperthyroidism, 3.27 (0.99-11.30). After excluding those with baseline use of thyroid-altering medications, men with endogenous subclinical hyperthyroidism had a higher HR of 4.91 (95% CI, 1.13-21.27), as did men with endogenous subclinical hypothyroidism (2.45, 1.27-4.73). Hip fracture incidence (per 1000 women-years) was 8.93 in women with subclinical hypothyroidism (n = 359) and 10.90 in women with subclinical hyperthyroidism (n = 142) compared with 10.18 in women with euthyroidism (n = 1694). No clear association between subclinical dysfunction and fracture was observed in women. CONCLUSIONS Older men with subclinical hyperthyroidism or hypothyroidism are at increased risk for hip fracture. Whether treatment of the subclinical syndrome reduces this risk is unknown.
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Schafer AL, Vittinghoff E, Ramachandran R, Mahmoudi N, Bauer DC. Laboratory reproducibility of biochemical markers of bone turnover in clinical practice. Osteoporos Int 2010; 21:439-45. [PMID: 19506793 PMCID: PMC2817087 DOI: 10.1007/s00198-009-0974-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 04/01/2009] [Accepted: 04/06/2009] [Indexed: 11/03/2022]
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.
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Cauley JA, LaCroix AZ, Robbins JA, Larson J, Wallace R, Wactawski-Wende J, Chen Z, Bauer DC, Cummings SR, Jackson R. Baseline serum estradiol and fracture reduction during treatment with hormone therapy: the Women's Health Initiative randomized trial. Osteoporos Int 2010; 21:167-77. [PMID: 19436934 PMCID: PMC2787820 DOI: 10.1007/s00198-009-0953-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Accepted: 03/27/2009] [Indexed: 12/26/2022]
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.
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Cesari M, Kritchevsky SB, Newman AB, Simonsick EM, Harris TB, Penninx BW, Brach JS, Tylavsky FA, Satterfield S, Bauer DC, Rubin SM, Visser M, Pahor M. Added value of physical performance measures in predicting adverse health-related events: results from the Health, Aging And Body Composition Study. J Am Geriatr Soc 2009; 57:251-9. [PMID: 19207142 DOI: 10.1111/j.1532-5415.2008.02126.x] [Citation(s) in RCA: 429] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVES To determine how three different physical performance measures (PPMs) combine for added utility in predicting adverse health events in elders. DESIGN Prospective cohort study. SETTING Health, Aging and Body Composition Study. PARTICIPANTS Three thousand twenty-four well-functioning older persons (mean age 73.6). MEASUREMENTS Timed gait, repeated chair stands, and balance (semi- and full-tandem, and single leg stands each held for 30 seconds) tests were administered at baseline. Usual gait speed was categorized to distinguish high- and low-risk participants using the previously established 1-m/s cutpoint. The same population-percentile (21.3%) was used to identify cutpoints for the repeated chair stands (17.1 seconds) and balance (53.0 seconds) tests. Cox proportional hazard analyses were performed to evaluate the added value of PPMs in predicting mortality, hospitalization, and (severe) mobility limitation events over 6.9 years of follow-up. RESULTS Risk estimates for developing adverse health-related events were similarly large for each of the three high-risk groups considered separately. Having more PPM scores at the high-risk level was associated with a greater risk of developing adverse health-related events. When all three PPMs were considered, having only one poor performance was sufficient to indicate a highly significantly higher risk of (severe) lower extremity and mortality events. CONCLUSION Although gait speed is considered to be the most important predictor of adverse health events, these findings demonstrate that poor performance on other tests of lower extremity function are equally prognostic. This suggests that chair stand and standing balance performance may be adequate substitutes when gait speed is unavailable.
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Cauley JA, Lacroix AZ, Wu L, Horwitz M, Danielson ME, Bauer DC, Lee JS, Jackson RD, Robbins JA, Wu C, Stanczyk FZ, LeBoff MS, Wactawski-Wende J, Sarto G, Ockene J, Cummings SR. Serum 25-hydroxyvitamin D concentrations and risk for hip fractures. Ann Intern Med 2008; 149:242-50. [PMID: 18711154 PMCID: PMC2743412 DOI: 10.7326/0003-4819-149-4-200808190-00005] [Citation(s) in RCA: 209] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND The relationship between serum 25-hydroxyvitamin D [25(OH) vitamin D] concentration and hip fractures is unclear. OBJECTIVE To see whether low serum 25(OH) vitamin D concentrations are associated with hip fractures in community-dwelling women. DESIGN Nested case-control study. SETTING 40 clinical centers in the United States. PARTICIPANTS 400 case-patients with incident hip fracture and 400 control participants matched on the basis of age, race or ethnicity, and date of blood draw. Both groups were selected from 39 795 postmenopausal women who were not using estrogens or other bone-active therapies and who had not had a previous hip fracture. MEASUREMENTS Serum 25(OH) vitamin D was measured and patients were followed for a median of 7.1 years (range, 0.7 to 9.3 years) to assess fractures. RESULTS Mean serum 25(OH) vitamin D concentrations were lower in case-patients than in control participants (55.95 nmol/L [SD, 20.28] vs. 59.60 nmol/L [SD, 18.05]; P = 0.007), and lower serum 25(OH) vitamin D concentrations increased hip fracture risk (adjusted odds ratio for each 25-nmol/L decrease, 1.33 [95% CI, 1.06 to 1.68]). Women with the lowest 25(OH) vitamin D concentrations (< or =47.5 nmol/L) had a higher fracture risk than did those with the highest concentrations (> or =70.7 nmol/L) (adjusted odds ratio, 1.71 [CI, 1.05 to 2.79]), and the risk increased statistically significantly across quartiles of serum 25(OH) vitamin D concentration (P for trend = 0.016). This association was independent of number of falls, physical function, frailty, renal function, and sex-steroid hormone levels and seemed to be partially mediated by bone resorption. LIMITATIONS Few case-patients were nonwhite women. Bone mineral density and parathyroid hormone levels were not accounted for in the analysis. CONCLUSION Low serum 25(OH) vitamin D concentrations are associated with a higher risk for hip fracture.
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Freitas SS, Barrett-Connor E, Ensrud KE, Fink HA, Bauer DC, Cawthon PM, Lambert LC, Orwoll ES. Rate and circumstances of clinical vertebral fractures in older men. Osteoporos Int 2008; 19:615-23. [PMID: 18038109 PMCID: PMC2492834 DOI: 10.1007/s00198-007-0510-1] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2007] [Accepted: 09/21/2007] [Indexed: 10/22/2022]
Abstract
UNLABELLED We examined the rate of clinical vertebral fractures, and the circumstances associated with the fractures, in a cohort of 5,995 US older men. Fractures were more common in the most elderly men, and were usually associated with falls and other low-energy trauma. INTRODUCTION Little is known about clinical vertebral fractures in older men. We postulated that clinical vertebral fractures occur with falls, affect men with osteoporosis, and are more common as age increases. METHODS Five thousand nine hundred and ninety-five men aged > or =65 years were followed prospectively for an average of 4.7 years. Men with incident clinical vertebral fractures were compared to controls. RESULTS One percent (n = 61) sustained incident clinical vertebral fractures (2.2/1,000 person-years). The rate of fracture rose with age (0.7% in men 65-69 years and 5% > or =85 years). Fractured men were more likely frail (8.2% vs. 2.2%), more often fell (36.1% vs. 21%) and had lower total hip and lumbar spine BMD (all p values < or =0.002). In 73.8% of cases fractures were precipitated by no known trauma or by low-energy trauma, including falls in 57.3% Fractures were thoracic in 33% and lumbar in 56%. Men with an incident vertebral fracture were more likely to be osteoporotic (13% vs. 2%, p < 0.0001), but most men with incident fractures did not have osteoporosis. CONCLUSIONS Incident clinical vertebral fractures were relatively common in older men and the rate increased after age 80 years. Fractures were usually associated with minimal trauma, most commonly a fall.
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Hunter DJ, Li J, LaValley M, Bauer DC, Nevitt M, DeGroot J, Poole R, Eyre D, Guermazi A, Gale D, Felson DT. Cartilage markers and their association with cartilage loss on magnetic resonance imaging in knee osteoarthritis: the Boston Osteoarthritis Knee Study. Arthritis Res Ther 2008; 9:R108. [PMID: 17958892 PMCID: PMC2212578 DOI: 10.1186/ar2314] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 09/12/2007] [Accepted: 10/24/2007] [Indexed: 11/24/2022] Open
Abstract
We used data from a longitudinal observation study to determine whether markers of cartilage turnover could serve as predictors of cartilage loss on magnetic resonance imaging (MRI). We conducted a study of data from the Boston Osteoarthritis of the Knee Study (BOKS), a completed natural history study of knee osteoarthritis (OA). All subjects in the study met American College of Rheumatology criteria for knee OA. Baseline and follow-up knee magnetic resonance images were scored for cartilage loss by means of the WORMS (Whole Organ Magnetic Resonance Imaging Score) semiquantitative grading scheme. Within the BOKS population, 80 subjects who experienced cartilage loss and 80 subjects who did not were selected for the purposes of this nested case control study. We assessed the baseline levels of cartilage degradation and synthesis products by means of assays for type I and II cleavage by collagenases (Col2:3/4Cshort or C1,2C), type II cleavage only with Col2:3/4Clongmono (C2C), type II synthesis (C-propeptide), the C-telopeptide of type II (Col2CTx), aggrecan 846 epitope, and cartilage oligomeric matrix protein (COMP). We performed a logistic regression to examine the relation of levels of each biomarker to the risk of cartilage loss in any knee. All analyses were adjusted for gender, age, and body mass index (BMI); results stratified by gender gave similar results. One hundred thirty-seven patients with symptomatic knee OA were assessed. At baseline, the mean (standard deviation) age was 67 (9) years and 54% were male. Seventy-six percent of the subjects had radiographic tibiofemoral OA (Kellgren & Lawrence grade of greater than or equal to 2) and the remainder had patellofemoral OA. With the exception of COMP, none of the other biomarkers was a statistically significant predictor of cartilage loss. For a 1-unit increase in COMP, the odds of cartilage loss increased 6.09 times (95% confidence interval [CI] 1.34 to 27.67). After the analysis of COMP was adjusted for age, gender, and BMI, the risk for cartilage loss was 6.35 (95% CI 1.36 to 29.65). Among subjects with symptomatic knee OA, a single measurement of increased COMP predicted subsequent cartilage loss on MRI. The other biochemical markers of cartilage synthesis and degradation do not facilitate prediction of cartilage loss. With the exception of COMP, if changes in cartilage turnover in patients with symptomatic knee OA are associated with cartilage loss, they do not appear to affect systemic biomarker levels.
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Shaffer JR, Kammerer CM, Reich D, McDonald G, Patterson N, Goodpaster B, Bauer DC, Li J, Newman AB, Cauley JA, Harris TB, Tylavsky F, Ferrell RE, Zmuda JM. Genetic markers for ancestry are correlated with body composition traits in older African Americans. Osteoporos Int 2007; 18:733-41. [PMID: 17235662 DOI: 10.1007/s00198-006-0316-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Accepted: 12/07/2006] [Indexed: 12/25/2022]
Abstract
UNLABELLED Individual-specific percent European ancestry was assessed in 1,277 African Americans. We found significant correlations between proportion of European ancestry and several musculoskeletal traits, indicating that admixture mapping may be a useful strategy for locating genes affecting these traits. INTRODUCTION Genotype data for admixed populations can be used to detect chromosomal regions influencing disease risk if allele frequencies at disease-related loci differ between parental populations. We assessed evidence for differentially distributed alleles affecting bone and body composition traits in African Americans. METHODS Bone mineral density (BMD) and body composition data were collected for 1,277 African and 1,790 European Americans (aged 70-79). Maximum likelihood methods were used to estimate individual-specific percent European ancestry for African Americans genotyped at 37 ancestry-informative genetic markers. Partial correlations between body composition traits and percent European ancestry were calculated while simultaneously adjusting for the effects of covariates. RESULTS Percent European ancestry (median = 18.7%) in African Americans was correlated with femoral neck BMD in women (r = -0.18, p < 10(-5)) and trabecular spine BMD in both sexes (r = -0.18, p < 10(-5)) independently of body size, fat, lean mass, and other covariates. Significant associations of European ancestry with appendicular lean mass (r = -0.19, p < 10(-10)), total lean mass (r = -0.12, p < 10(-4)), and total body fat (r = 0.09, p < 0.002) were also observed for both sexes. CONCLUSIONS These results indicate that some population differences in body composition may be due to population-specific allele frequencies, suggesting the utility of admixture mapping for identifying susceptibility genes for osteoporosis, sarcopenia, and obesity.
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Bauer DC, Ewing SK, Cauley JA, Ensrud KE, Cummings SR, Orwoll ES. Quantitative ultrasound predicts hip and non-spine fracture in men: the MrOS study. Osteoporos Int 2007; 18:771-7. [PMID: 17273893 DOI: 10.1007/s00198-006-0317-5] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Accepted: 12/07/2006] [Indexed: 11/26/2022]
Abstract
UNLABELLED Quantitative ultrasound (QUS) is associated with fracture risk in women, but there are few data in men. We studied 5,607 older men and found that QUS predicts hip and any non-spine fracture risk nearly as well as BMD. Combined measurements of QUS and BMD are not superior to either measurement alone. INTRODUCTION Quantitative ultrasound (QUS) predicts fracture risk among older women, but there are few prospective studies among older men. We studied the ability of QUS and BMD measurements to predict hip and other non-spine fractures in a population-based study of older men. METHODS Calcaneal QUS and hip BMD were measured in 5,607 men aged > or =65 years recruited from six US centers. At baseline duplicate QUS measurements with repositioning were obtained, and subsequent hip and other non-spine fractures were documented by review of x-rays or x-ray reports. The relationships between QUS and fractures were examined with proportional hazard models adjusted for age and clinic. We used receiver operating characteristic curves and predicted fracture risk models to determine the utility of QUS alone, BMD alone or the combination of QUS+BMD. RESULTS During a mean follow-up of 4.2 years with 99% complete follow-up, 239 men suffered a non-spine fracture, including 49 hip fractures. Each standard deviation reduction in broadband ultrasonic attenuation (BUA) was associated with an increased risk of hip (relative hazard=2.0, CI: 1.5, 2.8) and any non-spine fracture (relative hazard=1.6, CI: 1.4, 1.8). The area under the receiver operating characteristic curve and the predicted probability of fracture were similar for BUA alone, BMD alone and the combination of BUA+BMD, indicating that once BUA or BMD is known, the other measurement does not add useful information. Other QUS parameters gave similar results. CONCLUSIONS QUS measurements predict the risk of hip and any non-spine fracture in older men, and do so nearly as well as hip BMD measurements. Combined measurements of QUS and BMD are not superior to either measurement alone.
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Li R, Nicklas B, Pahor M, Newman A, Sutton-Tyrrell K, Harris T, Lakatta E, Bauer DC, Ding J, Satterfield S, Kritchevsky SB. Polymorphisms of angiotensinogen and angiotensin-converting enzyme associated with lower extremity arterial disease in the Health, Aging and Body Composition study. J Hum Hypertens 2007; 21:673-82. [PMID: 17429448 DOI: 10.1038/sj.jhh.1002198] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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.
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Rodondi N, Taylor BC, Bauer DC, Lui LY, Vogt MT, Fink HA, Browner WS, Cummings SR, Ensrud KE. Association between aortic calcification and total and cardiovascular mortality in older women. J Intern Med 2007; 261:238-44. [PMID: 17305646 DOI: 10.1111/j.1365-2796.2007.01769.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVES To determine whether older women with abdominal aortic calcification had a greater cardiovascular and all-cause mortality, as such data are limited in older adults. DESIGN Prospective cohort study with a mean follow-up of 13 years. SETTING Community-based sample with four US clinical centres. SUBJECTS A total of 2056 women aged > or =65 years with abdominal aortic calcification assessed on baseline radiographs. MAIN OUTCOME MEASURE Mortality rate (all, cardiovascular, cancer or other cause) adjudicated from death certificates and hospital records. RESULTS The prevalence of abdominal aortic calcification increased with age, ranging from 60% at age 65-69 years to 96% at 85 years and older. Participants with aortic calcification were more likely to die during follow-up of any cause (47% vs. 27%) or a cardiovascular-specific cause (18% vs. 11%, both P < 0.001) than those without aortic calcification. In age-adjusted analyses, aortic calcification was associated with a greater rate of all-cause and cause-specific mortality (cardiovascular, cancer, and other, all P < or = 0.01). In analyses adjusted for age and cardiovascular risk factors, aortic calcification was associated with an increased rate of all-cause mortality (HR: 1.37, 95% CI: 1.15-1.64), and noncardiovascular noncancer mortality (HR: 1.57, 95% CI: 1.17-2.11). The associations between aortic calcification and cancer mortality (HR: 1.44, 95% CI: 1.00-2.08) or cardiovascular mortality (HR: 1.18, 95% CI: 0.88-1.57) showed a similar pattern without reaching statistical significance, but was slightly stronger for mortality from coronary heart disease (HR: 1.53, 95% CI: 0.91-2.56). CONCLUSIONS Abdominal aortic calcification in older women is associated with increased mortality. Future research should examine potential mechanisms for this association.
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Schousboe JT, Bauer DC, Nyman JA, Kane RL, Melton LJ, Ensrud KE. Potential for bone turnover markers to cost-effectively identify and select post-menopausal osteopenic women at high risk of fracture for bisphosphonate therapy. Osteoporos Int 2007; 18:201-10. [PMID: 17019515 DOI: 10.1007/s00198-006-0218-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Accepted: 08/07/2006] [Indexed: 12/14/2022]
Abstract
INTRODUCTION AND HYPOTHESIS Over half of all fractures among post-menopausal women occur in those who do not have osteoporosis by bone density criteria. Measurement of bone turnover may cost-effectively identify a subset of women with T-score >-2.5 for whom anti-resorptive drug therapy is cost-effective. METHODS Using a Markov model, we estimated the cost per quality adjusted life year (QALY) for five years of oral bisphosphonate compared to no drug therapy for osteopenic post-menopausal women aged 60 to 80 years with a high (top quartile) or low (bottom 3 quartiles) level of a bone turnover marker. RESULTS For women with high bone turnover, the cost per QALY gained with alendronate compared to no drug therapy among women aged 70 years with T-scores of -2.0 or -1.5 were $58,000 and $80,000 (U.S. 2004 dollars), respectively. If bisphosphonates therapy also reduced the risk of non-vertebral fractures by 20% among osteopenic women with high bone turnover, then the costs per QALY gained were $34,000 and $50,000 for women age 70 with high bone turnover and T-scores of -2.0 and -1.5, respectively. CONCLUSION Measurement of bone turnover markers has the potential to identify a subset of post-menopausal women without osteoporosis by bone density criteria for whom bisphosphonate therapy to prevent fracture is cost-effective. The size of that subset highly depends on the assumed efficacy of bisphosphonates for fracture risk reduction among women with both a T-score >-2.5 and high bone turnover and the cost of bisphosphonate treatment.
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Hillier TA, Stone KL, Bauer DC, Rizzo JH, Pedula KL, Cauley JA, Ensrud KE, Hochberg MC, Cummings SR. Evaluating the Value of Repeat Bone Mineral Density Measurement and Prediction of Fractures in Older Women. ACTA ACUST UNITED AC 2007; 167:155-60. [PMID: 17242316 DOI: 10.1001/archinte.167.2.155] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Whether repeat bone mineral density (BMD) measurement adds benefit beyond the initial BMD measurement in predicting fractures in older women is unknown. METHODS We prospectively measured total hip BMD in 4124 older women (mean +/- SD age, 72 +/- 4 years) from 1989 to 1990 and again 8 years later. Incident nontraumatic hip and nonspine fractures were validated by radiology reports (>95% follow-up). In addition, spine fractures were defined morphometrically in 2129 of these women by lateral spine x-ray films from 1991 to 1992 and then again 11.4 years later. Prediction of fracture risk was assessed with proportional hazards models and receiver operating characteristic curves for BMD measures. RESULTS Over a mean of 5 years after the repeat BMD measure, 877 women experienced an incident nontraumatic nonspine fracture (275 hip fractures). In addition, 340 women developed a spine fracture. After adjustment for age and weight change, initial and repeat BMD measurements were similarly associated with fracture risk (per unit standard deviation lower in BMD) for nonspine (hazard ratio, 1.6), spine (odds ratio, 1.8-1.9), and hip (hazard ratio, 2.0-2.2) fractures (P<.001 for all models). Areas under the receiver operating characteristic curves (AUC) revealed no significant differences to discriminate nonspine (AUC, 0.65), spine (AUC, 0.67-0.68), or hip (AUC, 0.73-0.74) fractures between models with initial BMD, repeat BMD, or initial BMD plus change in BMD. Stratification by initial BMD t scores (normal, osteopenic, or osteoporotic), high bone loss, or hormone therapy did not alter results. CONCLUSION In healthy, older, postmenopausal women, repeating a measurement of BMD up to 8 years later provides little additional value besides the initial BMD measurement for predicting incident fractures.
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Abstract
Differential effectiveness of treatments across subgroups defined by pretreatment variables are of increasing interest, particularly in the expanding research field of pharmacogenomics. When the pretreatment variable is difficult to obtain or expensive to measure, but can be assessed at the end of the study using stored samples, nested case-control and case-cohort methods can be used to reduce costs in large efficacy trials with rare outcomes. Case-only methods are even more efficient, and reliable under a range of circumstances.
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Bauer DC, Hunter DJ, Abramson SB, Attur M, Corr M, Felson D, Heinegård D, Jordan JM, Kepler TB, Lane NE, Saxne T, Tyree B, Kraus VB. Classification of osteoarthritis biomarkers: a proposed approach. Osteoarthritis Cartilage 2006; 14:723-7. [PMID: 16733093 DOI: 10.1016/j.joca.2006.04.001] [Citation(s) in RCA: 279] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2006] [Accepted: 04/04/2006] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Osteoarthritis (OA) biomarkers are needed by researchers and clinicians to assist in disease diagnosis and assessment of disease severity, risk of onset, and progression. As effective agents for OA are developed and tested in clinical studies, biomarkers that reliably mirror or predict the progression or amelioration of OA will also be needed. METHODS The NIH-funded OA Biomarkers Network is a multidisciplinary group interested in the development and validation of OA biomarkers. This review summarizes our efforts to characterize and classify OA biomarkers. RESULTS We propose the "BIPED" biomarker classification (which stands for Burden of Disease, Investigative, Prognostic, Efficacy of Intervention and Diagnostic), and offer suggestions on optimal study design and analytic methods for use in OA investigations. CONCLUSION The BIPED classification provides specific biomarker definitions with the goal of improving our ability to develop and analyze OA biomarkers, and to communicate these advances within a common framework.
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Farhat GN, Strotmeyer ES, Newman AB, Sutton-Tyrrell K, Bauer DC, Harris T, Johnson KC, Taaffe DR, Cauley JA. Volumetric and areal bone mineral density measures are associated with cardiovascular disease in older men and women: the health, aging, and body composition study. Calcif Tissue Int 2006; 79:102-11. [PMID: 16927045 DOI: 10.1007/s00223-006-0052-0] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2006] [Accepted: 05/23/2006] [Indexed: 10/24/2022]
Abstract
The associations of volumetric (vBMD) and areal (aBMD) bone mineral density measures with prevalent cardiovascular disease (CVD) and subclinical peripheral arterial disease (PAD) were investigated in a cohort of older men and women enrolled in the Health, Aging, and Body Composition Study. Participants were 3,075 well-functioning white and black men and women (42% black, 51% women), aged 68-80 years. Total hip, femoral neck, and trochanter aBMD were measured using dual-energy X-ray absorptiometry. Quantitative computed tomography was used to evaluate spine trabecular, integral, and cortical vBMD measures in a subgroup (n = 1,489). Logistic regression was performed to examine associations of BMD measures with CVD and PAD. The prevalence of CVD (defined by coronary heart disease, PAD, cerebrovascular disease, or congestive heart failure) was 29.8%. Among participants without CVD, 10% had subclinical PAD (defined as ankle-arm index <0.9). Spine vBMD measures were inversely associated with CVD in men (odds ratio of integral [OR(integral)] = 1.34, 95% confidence interval [CI] 1.10-1.63; OR(trabecular )= 1.25, 95% CI 1.02-1.53; OR(cortical )= 1.36, 95% CI 1.11-1.65). In women, for each standard deviation decrease in integral vBMD, cortical vBMD, or trochanter aBMD, the odds of CVD were significantly increased by 28%, 27%, and 22%, respectively. Total hip aBMD was associated with subclinical PAD in men (OR = 1.39, 95% CI 1.03-1.84) but not in women. All associations were independent of age and shared risk factors between BMD and CVD and were not influenced by inflammatory cytokines (interleukin-6 and tumor necrosis factors-alpha). In conclusion, our results provide further evidence for an inverse association between BMD and CVD in men and women. Future research should investigate common pathophysiological links for osteoporosis and CVD.
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Bauer DC, Stavitsky AB. ON THE DIFFERENT MOLECULAR FORMS OF ANTIBODY SYNTHESIZED BY RABBITS DURING THE EARLY RESPONSE TO A SINGLE INJECTION OF PROTEIN AND CELLULAR ANTIGENS. Proc Natl Acad Sci U S A 2006; 47:1667-80. [PMID: 16590890 PMCID: PMC223190 DOI: 10.1073/pnas.47.10.1667] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Bauer DC, Garnero P, Bilezikian JP, Greenspan SL, Ensrud KE, Rosen CJ, Palermo L, Black DM. Short-term changes in bone turnover markers and bone mineral density response to parathyroid hormone in postmenopausal women with osteoporosis. J Clin Endocrinol Metab 2006; 91:1370-5. [PMID: 16449339 DOI: 10.1210/jc.2005-1712] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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.
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Jamal SA, Leiter RE, Jassal V, Hamilton CJ, Bauer DC. Impaired muscle strength is associated with fractures in hemodialysis patients. Osteoporos Int 2006; 17:1390-7. [PMID: 16799753 DOI: 10.1007/s00198-006-0133-y] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2005] [Accepted: 03/29/2006] [Indexed: 10/24/2022]
Abstract
INTRODUCTION Fractures are extremely common among hemodialysis (HD) patients. METHODS To assess if bone mineral density (BMD) and/or tests of muscle strength were associated with fractures, we studied 37 men and 15 women, 50 years and older, on HD for at least 1 year. We excluded subjects with prior renal transplants and women taking hormone replacement therapy. We inquired about low-trauma fractures since starting dialysis. Subjects underwent BMD testing with a Lunar DPX-L densitometer. Tests of muscle strength included: timed up and go (TUG), 6-min walk, functional reach, and grip strength. Lateral and thoracic radiographs of the spine were obtained and reviewed for prevalent vertebral fractures. We used logistic regression to examine associations between fracture (prevalent vertebral, self-reported low trauma since starting dialysis and/or both) and BMD, and fracture and muscle-strength tests. Analyses were adjusted for age, weight, and gender. RESULTS Mean age was 66+/-9.0 years, mean weight was 72.9+/-15.2 kg, and most (35 of 52) participants were Caucasian. Average duration of dialysis was 40.2 (interquartile range: 24-61.2) months. The most common cause of renal failure was diabetes (16 subjects). There were no differences by gender or fracture. Of the 52 subjects, 27 had either a vertebral fracture or low trauma fracture. There was no association between fractures, hip or spine BMD, or grip strength. In contrast, greater functional reach [odds ratio (OR) per standard deviation (SD) increase: 0.29; 95% CI: 0.13-0.69), quicker TUG (OR per SD decrease: 0.14; 95% CI: 0.11-0.23), and a greater distance walked in 6 min (OR per SD increase: 0.10; 95% CI: 0.03-0.36) were all associated with a reduced risk of fracture. CONCLUSIONS Impaired neuromuscular function is associated with fracture in hemodialysis patients.
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Yende S, Waterer GW, Tolley EA, Newman AB, Bauer DC, Taaffe DR, Jensen R, Crapo R, Rubin S, Nevitt M, Simonsick EM, Satterfield S, Harris T, Kritchevsky SB. Inflammatory markers are associated with ventilatory limitation and muscle dysfunction in obstructive lung disease in well functioning elderly subjects. Thorax 2005; 61:10-6. [PMID: 16284220 PMCID: PMC2080698 DOI: 10.1136/thx.2004.034181] [Citation(s) in RCA: 182] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Inflammatory markers are increased in chronic obstructive pulmonary disease (COPD) and are hypothesised to play an important part in muscle dysfunction and exercise intolerance. METHODS The Health Aging and Body Composition (Health ABC) study is a prospective observational cohort of well functioning individuals aged 70-79 years. A cross sectional analysis of the baseline data was conducted to examine the association between inflammatory markers and ventilatory limitation, muscle strength, and exercise capacity. These associations were compared in participants with and without obstructive lung disease (OLD). RESULTS Of the 3075 participants enrolled in the Health ABC cohort, OLD was identified by spirometric testing in 268 participants and 2005 participants had normal spirometric results. Of the participants with OLD, 35%, 38%, and 27% participants had mild, moderate, and severe OLD, respectively. Participants with OLD had lower quadriceps strength (102.5 Nm v 108.9 Nm, p = 0.02), lower maximum inspiratory pressure (64.7 cm H(2)O v 74.2 cm H(2)O, p<0.0001), higher systemic interleukin (IL)-6 levels (2.6 pg/ml v 2.2 pg/ml, p<0.0001), and higher C-reactive protein (CRP) levels (3.5 mg/l v 2.5 mg/l, p<0.0001) than those with normal spirometry. In participants with OLD and those with normal spirometry, forced expiratory volume in 1 second (FEV(1)) was associated with IL-6 (adjusted regression coefficients (beta) = -5.3 (95% CI -9.1 to-1.5) and -3.1 (95% CI -4.3 to -1.9), respectively). IL-6 and TNF were also associated with quadriceps strength among participants with OLD and those with normal spirometry (beta = -6.4 (95% CI -12.8 to -0.03) and -3.4 (95% CI -5.4 to -1.3), respectively, for IL-6 and beta = -10.1 (95% CI -18.7 to -1.5) and -3.8 (95% CI -7 to -0.6), respectively, for TNF). IL-6, quadriceps strength, and maximum inspiratory pressures were independent predictors of reduced exercise capacity in both groups. CONCLUSIONS In well functioning elderly subjects with or without OLD, IL-6 is associated with reduced FEV(1), quadriceps strength, and exercise capacity.
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Jamal SA, Leiter RE, Bauer DC. Hyperhomocysteinaemia and aortic calcification are associated with fractures in patients on haemodialysis. QJM 2005; 98:575-9. [PMID: 15983022 DOI: 10.1093/qjmed/hci092] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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.
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Duboeuf F, Bauer DC, Chapurlat RD, Dinten JMP, Delmas P. Assessment of vertebral fracture using densitometric morphometry. J Clin Densitom 2005; 8:362-8. [PMID: 16055969 DOI: 10.1385/jcd:8:3:362] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2004] [Revised: 01/14/2005] [Accepted: 03/28/2005] [Indexed: 11/11/2022]
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.
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