RESUMO
In a multi-site longitudinal cohort study, decreasing hemoglobin was associated with increased hip fracture risk in men. Anemia was associated with hip fracture in men and in African American women. Decreasing hemoglobin may be a marker of progressing bone fragility, making its serial measurement useful for fracture risk stratification. INTRODUCTION: Hematopoiesis and bone health are interdependent. Anemia has been associated with risk of fracture in humans. To further elucidate this relationship, we hypothesized that decreasing hemoglobin could indicate defective hematopoiesis and would also predict fracture risk. METHODS: We performed a prospective analysis from study baseline (1992) of the Cardiovascular Health Study, a multi-site longitudinal cohort study. A total of 4670 men and women, ages >65 years, who were able to consent and not institutionalized or wheelchair bound, had hemoglobin (Hb) measured in 1992. For 4006 subjects, Hb change from 1989 to 1992 was annualized and divided into sex-specific quartiles. Incident hip fractures were verified against Medicare claims data during a median follow-up of 11.8 years. RESULTS: Nested Cox proportional-hazard models estimated association of hip fracture with anemia (men Hb <13 g/dL, women Hb <12 g/dL) and separately, greatest Hb decrease (versus others). Anemia was associated with increased hip fracture risk in all men (HR 1.59; 95% CI 1.01-2.50) and African American women (HR 3.21; 95% CI 1.07-9.63). In men, an annualized Hb loss of >0.36 g/dL/year was associated with a higher risk of hip fracture (HR 1.67; 95% CI 1.10-2.54), which was lessened by anemia at the start of fracture follow-up (HR 1.53; 95% CI 0.99-2.39). CONCLUSIONS: Decreasing Hb may be an early marker for subsequent hip fracture risk in men, which may be less informative once an anemia threshold is crossed. Only African American women with anemia had increased hip fracture risk, suggesting a race difference in this relationship.
Assuntos
Fraturas do Quadril , Medicare , Idoso , Feminino , Hemoglobinas , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/etiologia , Humanos , Estudos Longitudinais , Masculino , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
Methodological limitations preclude determination of the association between sleep duration and bone mineral density (BMD) from existing literature. This was the first study to use objective sleep duration to determine its association with BMD. Nocturnal sleep duration, assessed objectively (actigraphy) or subjectively (questionnaire), was not independently associated with BMD in postmenopausal women. INTRODUCTION: Both long and short self-reported sleep durations are associated with low bone mineral density (BMD) in men and women. The association between sleep duration measured by actigraphy and BMD in postmenopausal women is unknown. METHODS: The Study of Osteoporotic Fractures (SOF) ancillary sleep study was used to determine the association between sleep duration and BMD at the total hip and femoral neck in postmenopausal women ≥ 75 years old. Sleep duration was assessed by wrist actigraphy (average 4 nights) and questionnaire. BMD was compared between postmenopausal women with short (< 6 h/night) vs. NIH-recommended (7-8 h/night) sleep durations. Data were analyzed using a 2-sample t test (unadjusted) and multivariate regression model (adjusted). Simple linear regression was used to estimate the difference in BMD per additional hour of sleep when sleep duration was considered as a continuous, rather than dichotomized, variable. RESULTS: Total hip BMD was higher in women with actigraphically assessed shorter sleep duration in unadjusted models only. No clinically or statistically significant differences in total hip or femoral neck BMD were observed according to nocturnal sleep duration after adjusting for body mass index (BMI) in dichotomized (N = 874) or continuous (N = 1624) sleep duration models or when subjective sleep duration was used. When sleep duration included daytime naps, longer sleep duration was associated with lower total hip BMD (ß = - 0.005, p = 0.04). CONCLUSIONS: Nocturnal sleep duration, whether assessed objectively (actigraphy) or subjectively (questionnaire), was not independently associated with BMD in older postmenopausal women.
Assuntos
Densidade Óssea/fisiologia , Pós-Menopausa/fisiologia , Sono/fisiologia , Absorciometria de Fóton/métodos , Actigrafia/métodos , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Colo do Fêmur/fisiologia , Articulação do Quadril/fisiologia , Humanos , Osteoporose Pós-Menopausa/fisiopatologia , Autorrelato , Inquéritos e Questionários , Fatores de TempoRESUMO
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.
Assuntos
Densidade Óssea , Fraturas Ósseas , Hipertireoidismo , Hipotireoidismo , Idoso , Doenças Assintomáticas , Feminino , Fraturas Ósseas/etiologia , Fraturas Ósseas/metabolismo , Fraturas Ósseas/prevenção & controle , Humanos , Hipertireoidismo/diagnóstico , Hipertireoidismo/epidemiologia , Hipertireoidismo/metabolismo , Hipotireoidismo/diagnóstico , Hipotireoidismo/epidemiologia , Hipotireoidismo/metabolismo , Masculino , Fatores de RiscoRESUMO
Bone loss following a fracture could increase the risk of future fractures. In this study, we found that elderly women who had an upper body fracture or multiple fractures lost more bone at the hip than those who did not fracture. This suggests a possible systemic bone loss response initiated by fracture. INTRODUCTION: A prior fracture is one of the strongest predictors of subsequent fracture risk, but the etiology of this phenomenon remains unclear. Systemic bone loss post-fracture could contribute to increased risk of subsequent fractures. Therefore, in this study, we investigated whether incident fractures, including those distant to the hip, are associated with accelerated loss of hip bone mineral density (BMD) in elderly women. METHODS: We analyzed data from 3956 Caucasian women aged ≥ 65 years who were enrolled in the Study of Osteoporotic Fractures and completed hip BMD measurements at study visit 4 (year 6) and visit 6 (year 10). Clinical fractures between visits 4 and 6 were ascertained from triannual questionnaires and centrally adjudicated by review of community radiographic reports. Subjects provided questionnaire information and clinical variables at examinations for known and potential covariates. Generalized linear models were used to calculate average annual percent change in total hip BMD between visits 4 and 6 for each incident fracture type and for upper body and lower body fractures combined. A subset of women (n = 3783) was analyzed for annual total hip BMD change between study visits 4 and 5 and between study visits 5 and 6 to evaluate change in total hip BMD during these 2-year intervals. RESULTS: Women with incident upper body fracture or incident lower body fracture exhibited reductions in total hip BMD of 0.89 and 0.77% per year, respectively, while women who did not fracture exhibited reductions in total hip BMD of 0.66% per year during the 4-year period. Accelerated loss of hip BMD was isolated to the 2-year time interval that included the fracture. Loss of total hip BMD was not affected by the number of days from fracture to follow up DXA. CONCLUSIONS: Systemic bone loss following fracture may increase the risk of future fractures at all skeletal sites. There is a need for improved understanding of mechanisms leading to apparent accelerated bone loss following a fracture in order to reduce subsequent fracture risk.
Assuntos
Articulação do Quadril/fisiopatologia , Osteoporose/epidemiologia , Fraturas por Osteoporose/epidemiologia , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Progressão da Doença , Feminino , Humanos , Incidência , Osteoporose/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Recidiva , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
In the absence of clinically recognized cardiovascular disease, increased carotid artery intimal medial thickness was associated with higher hip fracture risk in older adults, despite its association with higher bone mineral density (BMD). Low ankle brachial index and aortic wall thickness were not associated with fracture risk or BMD. INTRODUCTION: Clinically recognized cardiovascular disease (CVD) is associated with osteoporosis and hip fracture risk, but the relationship of subclinical atherosclerosis to bone health is not certain. METHODS: We followed 3385 participants from the Cardiovascular Health Study (mean age 74.7 ± 5.3 years) with a median time to fracture of 12.1 years who underwent baseline carotid artery and aortic wall ultrasound scanning and ankle brachial blood pressure index (ABI) determinations. A subset underwent bone mineral density (BMD) testing. RESULTS: There were 494 hip fractures during follow-up. Among persons without clinical CVD, an average standard-deviation increase in a composite score of maximal common and internal carotid artery intimal medial thickness (cIMT) was associated with increased risk of hip fracture [(HR 1.18 [1.04, 1.35]), even though cIMT was positively associated with BMD. Neither aortic wall thickness nor ABI were associated with hip fracture risk or BMD. Among participants with clinical CVD, cIMT and aortic wall thickness, but not ABI, were associated with increased hip fracture risk. CONCLUSION: Subclinical cIMT is associated with an increased risk of hip fractures despite being associated with increased BMD. This finding suggests that vascular health, even in its early stages, is linked to bone health, by pathways other than BMD.
Assuntos
Aterosclerose/complicações , Densidade Óssea/fisiologia , Fraturas do Quadril/etiologia , Fraturas por Osteoporose/etiologia , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/epidemiologia , Aterosclerose/fisiopatologia , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/epidemiologia , Feminino , Seguimentos , Inquéritos Epidemiológicos , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/fisiopatologia , Humanos , Masculino , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/fisiopatologia , Medição de Risco/métodos , Estados Unidos/epidemiologiaRESUMO
There was no association of plasma DPP-4 activity levels with bone mineral density (BMD), body composition, or incident hip fractures in a cohort of elderly community-dwelling adults. INTRODUCTION: Dipeptidyl peptidase IV (DPP-4) inactivates several key hormones including those that stimulate postprandial insulin secretion, and DPP-4 inhibitors (gliptins) are approved to treat diabetes. While DPP-4 is known to modulate osteogenesis, the relationship between DPP-4 activity and skeletal health is uncertain. The purpose of the present study was to examine possible associations between DPP-4 activity in elderly subjects enrolled in the Cardiovascular Health Study (CHS) and BMD, body composition measurements, and incident hip fractures. METHODS: All 1536 male and female CHS participants who had evaluable DXA scans and plasma for DPP-4 activity were included in the analyses. The association between (1) BMD of the total hip, femoral neck, lumbar spine, and total body; (2) body composition measurements (% lean, % fat, and total body mass); and (3) incident hip fractures and plasma levels of DPP-4 activity were determined. RESULTS: Mean plasma levels of DPP-4 activity were significantly higher in blacks (227 ± 78) compared with whites (216 ± 89) (p = 0.04). However, there was no significant association of DPP-4 activity with age or gender (p ≥ 0.14 for both). In multivariable adjusted models, there was no association of plasma DPP-4 activity with BMD overall (p ≥ 0.55 for all) or in gender stratified analyses (p ≥ 0.23). There was also no association of DPP-4 levels and incident hip fractures overall (p ≥ 0.24) or in gender stratified analyses (p ≥ 0.39). CONCLUSION: Plasma DPP-4 activity, within the endogenous physiological range, was significantly associated with race, but not with BMD, body composition, or incident hip fractures in elderly community-dwelling subjects.
Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Dipeptidil Peptidase 4/sangue , Fraturas do Quadril/sangue , Idoso , Idoso de 80 Anos ou mais , População Negra/estatística & dados numéricos , Diabetes Mellitus/sangue , Diabetes Mellitus/etnologia , Diabetes Mellitus/fisiopatologia , Dipeptidil Peptidase 4/fisiologia , Feminino , Fraturas do Quadril/etnologia , Fraturas do Quadril/fisiopatologia , Humanos , Incidência , Estudos Longitudinais , Masculino , Fatores Sexuais , Estados Unidos/epidemiologia , População Branca/estatística & dados numéricosRESUMO
In this prospective cohort of 4462 older adults, incident atrial fibrillation (AF) was not statistically significantly associated with subsequent risk of incident fracture. INTRODUCTION: AF is associated with stroke, heart failure, dementia, and death, but its association with fracture is unknown. Therefore, we examined the association of incident AF with the risk of subsequent fracture in the Cardiovascular Health Study (CHS) cohort. METHODS: Of the CHS participants aged ≥65 years, 4462 were followed between 1991 and 2009, mean follow-up 8.8 years. Incident AF was identified by annual study electrocardiogram (ECG), hospital discharge diagnosis codes, or Medicare claims. Fractures of the hip, distal forearm, humerus, or pelvis were identified using hospital discharge diagnosis codes or Medicare claims. We used Cox proportional hazard models to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for the association between incident AF (time-varying) and the risk of subsequent fracture. We also evaluated whether AF was associated with risk of sustaining a fall. RESULTS: Crude incident fracture rate was 22.9 per 1000 person-years in participants with AF and 17.7 per 1000 person-years in participants without AF. Individuals with incident AF were not at significantly higher risk of hip fracture (adjusted HR = 1.09, 95 % CI 0.83-1.42) or fracture at any selected site (adjusted HR = 0.97, 95 % CI 0.77-1.22) or risk of sustaining a fall (adjusted HR = 1.00, 95 % CI = 0.87-1.16) compared with those without AF. CONCLUSION: In this cohort of older, community-dwelling adults, incident AF was not shown to be associated with falls or hip or other fractures.
Assuntos
Fibrilação Atrial/epidemiologia , Fraturas por Osteoporose/epidemiologia , Acidentes por Quedas/estatística & dados numéricos , Idoso , Comorbidade , Feminino , Fraturas do Quadril/epidemiologia , Humanos , Incidência , Estudos Longitudinais , Masculino , Estudos Prospectivos , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: Strongylus vulgaris has become a rare parasite in Germany during the past 50 years due to the practice of frequent prophylactic anthelmintic therapy. To date, the emerging development of resistance in Cyathostominae and Parascaris spp. to numerous equine anthelmintics has changed deworming management and the frequency of anthelmintic usage. In this regard, reliable detection of parasitic infections, especially of the highly pathogenic S. vulgaris is essential. In the current study, two diagnostic methods for the detection of infections with S. vulgaris were compared and information on the occurrence of this parasite in German horses was gained. For this purpose, faecal samples of 501 horses were screened for S. vulgaris with real-time PCR and an additional larval culture was performed in samples of 278 horses. A subset of 26 horses underwent multiple follow-up examinations with both methods in order to evaluate both the persistence of S. vulgaris infections and the reproducibility of each diagnostic method. RESULTS: The real-time PCR revealed S. vulgaris-DNA in ten of 501 investigated equine samples (1.9%). The larval culture demonstrated larvae of S. vulgaris in three of the 278 samples (1.1%). A direct comparison of the two methods was possible in 321 samples including 43 follow-up examinations with the result of 11 S. vulgaris-positive samples by real-time PCR and 4 S. vulgaris-positive samples by larval culture. The McNemar's test (p-value = 0.016) revealed a significant difference and the kappa values (0.525) showed a moderate agreement between real-time PCR and larval culture. CONCLUSIONS: The real-time PCR detected a significantly higher proportion of positives of S. vulgaris compared to larval culture and should thus be considered as a routine diagnostic method for the detection of S. vulgaris in equine samples.
Assuntos
Fezes/parasitologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Infecções Equinas por Strongyloidea/parasitologia , Strongylus/isolamento & purificação , Animais , Cavalos , Larva/fisiologia , Contagem de Ovos de Parasitas/veterinária , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções Equinas por Strongyloidea/diagnósticoRESUMO
UNLABELLED: We examined whether blood levels of two markers of fibrosis (transforming growth factor beta one (TGF-ß1) and procollagen type III N-terminal propeptide (PIIINP)) are related to hip fracture risk and to bone mineral density (BMD). TGF-ß1 levels were associated with lower hip fracture risk in women and with lower BMD in men. PIIINP levels were not associated with either outcome. INTRODUCTION: TGF-ß1 serves several roles in bone formation and resorption. A consequence of TGF-ß1 activation is the production of PIIINP, a marker of collagen III deposition. Here, we explore whether these two biomarkers are related to incident hip fracture and bone mineral density (BMD) and whether their associations are modified by systemic inflammation, as measured by C-reactive protein (CRP) levels. METHODS: Participants were from the Cardiovascular Health Study (mean age 78 years; mean follow-up 8.3 years). We included 1681 persons with measured levels of TGF-ß1 (149 hip fractures) and 3226 persons with measured levels of PIIINP (310 hip fractures). RESULTS: Among women, higher TGF-ß1 levels were associated with lower hip fracture risk (HR, per doubling, 0.78 [95 % CI 0.61, 0.91]). Among men, TGF-ß1 levels were associated with hip fracture risk in a non-linear manner, but among those with elevated CRP levels, doubling was associated with increased risk of fracture (HR 2.22 [1.20, 4.08]) (p = 0.02, interaction between low and high CRP and TGF-ß1 on fracture risk). TGF-ß1 levels had no significant association with total hip or total body BMD in women but were significantly associated with lower BMD in men. There were no associations of PIIINP levels with hip fracture risk or BMD in men or women. CONCLUSIONS: TGF-ß1 levels appear to be associated with bone-related phenotypes in a sex-specific manner. The reasons for these differences between men and women regarding TGF-ß1 levels and hip fracture risk and bone density require further investigation.
Assuntos
Densidade Óssea/fisiologia , Fraturas do Quadril/sangue , Fraturas por Osteoporose/sangue , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Fator de Crescimento Transformador beta/sangue , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Feminino , Fibrose , Seguimentos , Fraturas do Quadril/fisiopatologia , Humanos , Masculino , Fraturas por Osteoporose/fisiopatologia , Estudos Prospectivos , Fatores de Risco , Fatores SexuaisRESUMO
Here we report that abnormal brain white matter and, to a lesser extent, albuminuria are associated with reduced bone mineral density in the hip, spine, and total body in men and women. These findings may explain the increased hip fracture risk reported in some studies in association with microvascular disorders. INTRODUCTION: Markers of microvascular disease have been individually associated with increased risk of osteoporotic fractures in some studies. Here, we examine whether these markers are associated with reduced bone mineral density (BMD) individually and together. METHODS: BMD testing using dual x-ray absorptiometry of the hip, lumbar spine, and total body was performed in 1473 participants from the Cardiovascular Health Study (mean age ~ 78 years): 1215 were assessed for urinary albumin-creatinine ratio, 944 for abnormal white matter disease (AWMD) by brain MRI, and 541 for retinal vascular disease with fundus photographs. Linear regression models were used to evaluate the cross-sectional association of each marker with BMD accounting for potentially confounding factors. RESULTS: AWMD was associated with lower hip, spine, and total body BMD in women (ß -3.08 to -4.53; p < 0.01 for all) and lower hip and total body BMD in men (ß -2.90 to -4.24; p = 0.01-0.03). Albuminuria was associated with lower hip (ß -3.37; p = .05) and total body (ß -3.21; p = .02) BMD in men, but not in women. The associations of AWMD and albuminuria with BMD persisted with mutual adjustment and appeared to be additive to each other. Retinal vascular disease was not associated with BMD in men or women. CONCLUSION: AWMD and, to a lesser extent, albuminuria were independently associated with lower BMD, suggesting that microvascular disease may play a role in the pathogenesis of reduced BMD. These findings need to be confirmed by longitudinal studies.
Assuntos
Densidade Óssea , Nefropatias/epidemiologia , Leucoencefalopatias/epidemiologia , Microcirculação , Doenças Retinianas/epidemiologia , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Albuminúria/epidemiologia , Creatinina/urina , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Fraturas por Osteoporose , Fatores de RiscoRESUMO
UNLABELLED: Soluble CD14 (sCD14) is an inflammatory marker associated with osteoclasts. Using Cox proportional hazards models, we found a positive association between plasma levels of sCD14 and risk of incident fracture among participants in the Cardiovascular Health Study. sCD14 may be useful in identifying those at risk for fracture. INTRODUCTION: Soluble CD14, a proinflammatory cytokine, is primarily derived from macrophages/monocytes that can differentiate into osteoclasts. The purpose of this study was to examine the relationship between sCD14 levels and osteoporotic fractures. METHODS: In the Cardiovascular Health Study, 5462 men and women had sCD14 levels measured at baseline. Incident hip fractures (median follow-up time 12.5 years) and incident composite fractures (defined as the first hip, pelvis, humerus, or distal radius fracture, median follow-up 8.6 years) were identified from hospital discharge summaries and/or Medicare claims data. Cox proportional hazards models were used to model the association between sCD14 levels and time to incident hip or composite fracture, overall and as a function of race and gender. RESULTS: In unadjusted models, there was a positive association between sCD14 levels (per 1 standard deviation increase, i.e., 361.6 ng/mL) and incident hip (HR, 1.26; 95 % CI, 1.17, 1.36) and composite (HR, 1.20; 95 % CI, 1.12, 1.28) fractures. When models were fully adjusted for demographics, lifestyle factors, and medication use, these associations were no longer significant. However, in whites, the association of sCD14 levels with hip fractures remained significant in fully adjusted models (HR, 1.11; 95 % CI, 1.01-1.23). Associations of sCD14 levels with hip and composite fracture did not differ between men and women. CONCLUSIONS: In this large cohort of community-dwelling older adults, higher sCD14 levels were associated with an increased risk of incident hip fractures in whites.
Assuntos
Mediadores da Inflamação/sangue , Receptores de Lipopolissacarídeos/sangue , Fraturas por Osteoporose/sangue , Idoso , Biomarcadores/sangue , Feminino , Fraturas do Quadril/sangue , Fraturas do Quadril/epidemiologia , Humanos , Estimativa de Kaplan-Meier , Estudos Longitudinais , Masculino , Fraturas por Osteoporose/epidemiologia , Medição de Risco/métodos , Solubilidade , Estados Unidos/epidemiologiaRESUMO
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.
Assuntos
Testes Diagnósticos de Rotina/métodos , Osteoporose/etiologia , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biomarcadores/urina , Densidade Óssea/fisiologia , Estudos Transversais , Humanos , Masculino , Osteoporose/fisiopatologia , Estudos Prospectivos , Procedimentos Desnecessários , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/diagnósticoRESUMO
In coherent diffractive imaging, the resolution of the reconstructed object is limited by the numerical aperture of the experimental setup. We present here a theoretical and numerical study for achieving super-resolution by postextrapolation of coherent diffraction images, such as diffraction patterns or holograms. We demonstrate that a diffraction pattern can unambiguously be extrapolated from only a fraction of the entire pattern and that the ratio of the extrapolated signal to the originally available signal is linearly proportional to the oversampling ratio. Although there could be in principle other methods to achieve extrapolation, we devote our discussion to employing iterative phase retrieval methods and demonstrate their limits. We present two numerical studies; namely, the extrapolation of diffraction patterns of nonbinary and that of phase objects together with a discussion of the optimal extrapolation procedure.
RESUMO
BACKGROUND: The aim of this dose-finding study was to evaluate the dose-response relationship of sugammadex and neostigmine to reverse a commonly observed level of incomplete recovery from rocuronium-induced neuromuscular block, that is, a train-of-four ratio (TOFR) ≥0.2. METHODS: Ninety-nine anaesthetized patients received rocuronium 0.6 mg kg(-1) i.v. for tracheal intubation and, if necessary, incremental doses of 0.1-0.2 mg kg(-1). Neuromuscular monitoring was performed by calibrated electromyography. Once the TOFR recovered to 0.2, patients were randomized to receive sugammadex (0.25, 0.5, 0.75, 1.0, or 1.25 mg kg(-1) i.v.), neostigmine (10, 25, 40, 55, or 70 µg kg(-1) i.v.), or saline (n=9 per group). Primary and secondary end points were the doses necessary to restore neuromuscular function to a TOFR≥0.9 with an upper limit of 5 and 10 min for 95% of patients, respectively. RESULTS: Neostigmine was not able to fulfil the end points. Based on the best-fitting model, the sugammadex dose estimation for recovery to a TOFR≥0.9 for 95% of patients within 5 and 10 min was 0.49 and 0.26 mg kg(-1), respectively. CONCLUSION: A residual neuromuscular block of a TOFR of 0.2 cannot be reversed reliably with neostigmine within 10 min. In the conditions studied, substantially lower doses of sugammadex than the approved dose of 2.0 mg kg(-1) may be sufficient to reverse residual rocuronium-induced neuromuscular block at a recovery of TOFR≥0.2. CLINICAL TRIAL REGISTRATION: NCT01006720.
Assuntos
Eletromiografia/estatística & dados numéricos , Neostigmina/farmacologia , Bloqueio Neuromuscular , Monitoração Neuromuscular/estatística & dados numéricos , Fármacos Neuromusculares não Despolarizantes/antagonistas & inibidores , gama-Ciclodextrinas/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Androstanóis/antagonistas & inibidores , Período de Recuperação da Anestesia , Inibidores da Colinesterase/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rocurônio , Cloreto de Sódio/administração & dosagem , Sugammadex , Adulto JovemRESUMO
BACKGROUND: A train-of-four ratio (TOFR) ≥0.9 measured by quantitative neuromuscular monitoring is accepted as an indication of sufficient neuromuscular recovery for extubation, even though many postsynaptic acetylcholine receptors may still be inhibited. We investigated whether antagonism with sugammadex after spontaneous recovery to TOFR≥0.9 further improves muscle function or subjective well-being. METHODS: Following recovery to TOFR≥0.9 and emergence from anaesthesia, 300 patients randomly received either sugammadex 1.0 mg kg(-1) or placebo. Fine motor function (Purdue Pegboard Test) and maximal voluntary grip strength were measured before and after surgery (before and after test drug administration). At discharge from the postanaesthesia care unit, well-being was assessed with numerical analogue scales and the Quality-of-Recovery Score 40 (QoR-40). RESULTS: Patients' fine motor function [6 (sd 4) vs 15 (3) pegs (30 s)(-1), P<0.05] and maximal voluntary grip strength (284 (126) vs 386 (125) N, P<0.05) were significantly lower after anaesthesia compared with the pre-anaesthesia baseline. After sugammadex or placebo, motor function was significantly improved in both groups but did not reach the preoperative level. There was no difference between groups at any time. Global well-being was unaffected (QoR-40: placebo, 174 vs 185; sugammadex, 175 vs 186, P>0.05). CONCLUSIONS: Antagonizing rocuronium at TOF≥0.9 with sugammadex 1.0 mg kg(-) (1) did not improve patients' motor function or well-being when compared with placebo. Our data support the view that TOFR≥0.9 measured by electromyography signifies sufficient recovery of neuromuscular function. CLINICAL TRIAL REGISTRATION: The trial is registered at ClinicalTrials.gov (NCT01101139).
Assuntos
Androstanóis/antagonistas & inibidores , Período de Recuperação da Anestesia , Destreza Motora/efeitos dos fármacos , Monitoração Neuromuscular/métodos , Fármacos Neuromusculares não Despolarizantes/antagonistas & inibidores , gama-Ciclodextrinas/farmacologia , Adulto , Análise de Variância , Androstanóis/farmacologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Força Muscular/efeitos dos fármacos , Fármacos Neuromusculares não Despolarizantes/farmacologia , Rocurônio , SugammadexRESUMO
BACKGROUND: Similar to volatile anaesthetics, propofol may influence neuromuscular transmission. We hypothesised that the administration of propofol influenced the potency of rocuronium depending on the duration of the administration. METHODS: After consent, patients scheduled for elective surgery randomly received rocuronium either after induction of anaesthesia with propofol (2 min of propofol, n = 36) or after 30 min of propofol infusion (30 min of propofol, n = 36). Remifentanil was given in both groups. Neuromuscular monitoring was performed by calibrated electromyography. The dose-response relationship of rocuronium was determined with a single-bolus technique (0.07, 0.1, 0.15, 0.2, 0.3 and 0.45 mg/kg rocuronium). The primary endpoints were the ED50 and ED95 of rocuronium after 2 and 30 min propofol. Data are presented as means with (95% confidence interval). The trial is registered with the Eudra-CT: 2009-012815-16. RESULTS: A total of 72 patients were included. Time to maximal neuromuscular blockade was significantly shorter in patients after 30 min of propofol [3.3 min (2.9-3.7)] compared with patients anaesthetised with 2 min of propofol [4.6 min (4.0-5.2)]. After 30 min of propofol, the slope of the dose-response curve was significantly steeper (30 min of propofol: 4.34 [3.62-5.05]; 2 min of propofol: [3.34 (2.72-3.96)], resulting in lower ED95 values of rocuronium (30 min of propofol: 0.287 mg/kg [0.221-0.368]; 2 min of propofol [0.391 mg/kg (0.296-0.520)]. The ED50 were not different between groups. CONCLUSION: The potency of rocuronium was significantly enhanced after propofol infusion for 30 min. Estimates of potency those are usually determined during steady-state anaesthesia might underestimate rocuronium requirements for endotracheal intubation at the time of induction.
Assuntos
Androstanóis/farmacologia , Anestésicos Intravenosos/farmacologia , Bloqueio Neuromuscular/métodos , Fármacos Neuromusculares não Despolarizantes/farmacologia , Propofol/farmacologia , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Sinergismo Farmacológico , Eletromiografia/efeitos dos fármacos , Feminino , Humanos , Intubação Intratraqueal , Masculino , Pessoa de Meia-Idade , Rocurônio , Fatores de Tempo , Adulto JovemRESUMO
UNLABELLED: In this study, the area under the curve was highest when using the lowest vertebral body T-score to diagnose osteoporosis. In men for whom hip imaging is not possible, the lowest vertebral body T-score improves the ability to diagnose osteoporosis in men who are likely to have an incident fragility fracture. INTRODUCTION: Spine T-scores have limited ability to predict fragility fracture. We hypothesized that using lowest vertebral body T-score to diagnose osteoporosis would better predict fracture. METHODS: Among men enrolled in the Osteoporotic Fractures in Men Study, we identified cases with incident clinical fracture (n = 484) and controls without fracture (n = 1,516). We analyzed the lumbar spine bone mineral density (BMD) in cases and controls (n = 2,000) to record the L1-L4 (referent), the lowest vertebral body, and International Society for Clinical Densitometry (ISCD)-determined T-scores using a male normative database and the L1-L4 T-score using a female normative database. We compared the ability of method to diagnose osteoporosis and, therefore, to predict incident clinical fragility fracture, using area under the receiver operator curves (AUCs) and the net reclassification index (NCI) as measures of diagnostic accuracy. ISCD-determined T-scores were determined in only 60 % of participants (n = 1,205). RESULTS: Among 1,205 men, the AUC to predict incident clinical fracture was 0.546 for L1-L4 male, 0.542 for the L1-L4 female, 0.585 for lowest vertebral body, and 0.559 for ISCD-determined T-score. The lowest vertebral body AUC was the only method significantly different from the referent method (p = 0.002). Likewise, a diagnosis of osteoporosis based on the lowest vertebral body T-score demonstrated a significantly better net reclassification index (NRI) than the referent method (net NRI +0.077, p = 0.005). By contrast, the net NRI for other methods of analysis did not differ from the referent method. CONCLUSION: Our study suggests that in men, the lowest vertebral body T-score is an acceptable method by which to estimate fracture risk.
Assuntos
Densidade Óssea/fisiologia , Vértebras Lombares/fisiopatologia , Osteoporose/diagnóstico , Fraturas por Osteoporose/etiologia , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Osteoporose/complicações , Osteoporose/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de RiscoRESUMO
UNLABELLED: Prior studies suggest an association between stressful life events and fractures that may be mediated by BMD. In the current study, risk of accelerated hip BMD loss was higher in older men with any type of stressful life event and increased with the number of types of stressful life events. INTRODUCTION: Prior studies suggest that stressful life events may increase adverse health outcomes, including falls and possibly fractures. The current study builds on these findings and examines whether stressful life events are associated with increased bone loss. METHODS: Four thousand three hundred eighty-eight men aged ≥65 years in the Osteoporotic Fractures in Men study completed total hip bone mineral density (BMD) measures at baseline and visit 2, approximately 4.6 years later, and self-reported stressful life events data mid-way between baseline and visit 2, and at visit 2. We used linear regression to model the association of stressful life events with concurrent annualized total hip BMD loss, and log binomial regression or Poisson regression to model risk of concurrent accelerated BMD loss (>1 SD more than mean annualized change). RESULTS: Men (75.3 %) reported ≥1 type of stressful life event, including 43.3 % with ≥2 types of stressful life events. Mean annualized BMD loss was -0.36 % (SD 0.88), and 13.9 % of men were categorized with accelerated BMD loss (about 5.7 % or more total loss). Rate of annualized BMD loss increased with the number of types of stressful life events after adjustment for age (p < 0.001), but not after multivariable adjustment (p = 0.07). Multivariable-adjusted risk of accelerated BMD loss increased with the number of types of stressful life events (RR, 1.10 [95 % confidence interval (CI), 1.04-1.16]) per increase of one type of stressful life event). Fracture risk was not significantly different between stressful life event-accelerated bone loss subgroups (p = 0.08). CONCLUSIONS: In these older men, stressful life events were associated with a small, dose-related increase in risk of concurrent accelerated hip bone loss. Low frequency of fractures limited assessment of whether rapid bone loss mediates any association of stressful life events with incident fractures. Future studies are needed to confirm these findings and to investigate the mechanism that may underlie this association.
Assuntos
Acontecimentos que Mudam a Vida , Osteoporose/etiologia , Estresse Psicológico/complicações , Absorciometria de Fóton/métodos , Idoso , Densidade Óssea/fisiologia , Progressão da Doença , Articulação do Quadril/fisiopatologia , Humanos , Masculino , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/fisiopatologia , Fatores de Risco , Estresse Psicológico/epidemiologia , Estresse Psicológico/fisiopatologia , Estados Unidos/epidemiologiaRESUMO
Dopaminergic, serotonergic, and adrenergic receptors are targets for therapeutic actions in schizophrenia. Dopamine D2 receptor partial agonists such as aripiprazole represent a treatment option for patients with this severe disorder. The ineffectiveness of terguride, another D2 receptor partial agonist, in treating schizophrenia was recently attributed to its considerably high intrinsic activity at D2 receptors. In this study, we used functional assays for recombinant D2 receptors and native 5-hydroxytryptamine 2A (5-HT2A), α2C-adrenergic, and histamine H1 receptors to compare the pharmacological properties of terguride and three of its halogenated derivatives (2-chloro-, 2-bromo-, 2-iodoterguride) with those of aripiprazole. Subsequently, we studied the antidopaminergic effects of 2-bromoterguride using amphetamine-induced locomotion (AIL). Its influence on spontaneous behavior was tested in the open field. Extrapyramidal side effect (EPS) liability was evaluated by catalepsy test. In a guanosine 5'-O-(3-[(35)S]thio)triphosphate ([(35)S]GTPγS) binding assay, 2-chloro-, 2-bromo-, and 2-iodoterguride produced intrinsic activities at human D2short (hD2S) receptors that were half as high as the intrinsic activity for terguride; aripiprazole lacked agonist activity. 2-Bromoterguride and aripiprazole activated D2S receptor-mediated inhibition of cAMP accumulation to the same extent; intrinsic activity was half as high as that of terguride. All compounds tested behaved as antagonists at human D2long/Gαo (hD2L/Gαo) receptors. Compared with aripiprazole, terguride and its derivatives displayed higher affinity at porcine 5-HT2A receptors and α2C-adrenoceptors and lower affinity at H1 receptors. 2-Bromoterguride inhibited AIL and did not induce catalepsy in rats. Because of its in vitro and in vivo properties, 2-bromoterguride may be a strong candidate for the treatment of schizophrenia with a lower risk to induce EPS.
Assuntos
Antipsicóticos/administração & dosagem , Antipsicóticos/metabolismo , Agonistas de Dopamina/metabolismo , Lisurida/análogos & derivados , Receptor 5-HT2A de Serotonina/metabolismo , Receptor 5-HT2C de Serotonina/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Células CHO , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/metabolismo , Cricetinae , Cricetulus , Agonistas de Dopamina/química , Agonistas de Dopamina/farmacologia , Células HEK293 , Humanos , Lisurida/química , Lisurida/metabolismo , Lisurida/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Técnicas de Cultura de Órgãos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D2/agonistas , SuínosRESUMO
UNLABELLED: The microcirculation plays an important role in bone health. Here, we examine whether albuminuria, a marker of renal microvascular disease, is associated with the risk of hip fracture in older adults (age, 78 years). We find a small independent association in women but not in men. INTRODUCTION: The microvascular circulation plays an important role in bone physiology. Two studies of middle-aged adults have found that albuminuria (>30 mg albumin/g creatinine), a disorder of the renal microvasculature, is associated with fracture risk. Here, we examine whether albuminuria is related to hip fracture risk and reduced hip bone mineral density (BMD) in older adults with a mean age of 78 years. METHODS: From the Cardiovascular Health Study (41 % male), 3,110 adults with albuminuria testing were followed up for incident hip fracture for up to 9.5 years. BMD was performed in a subset of 1,208 participants. RESULTS: There were 313 hip fractures during follow-up (7.7 % of men; 11.7 % of women). The incidence rate for men, with and without albuminuria, was 1.43 and 0.93/100 person-years of follow-up (p = 0.02); for women, 1.84 and 1.33 (p = 0.04). After adjustment for osteoporosis-related factors, frailty and falling, a doubling of albuminuria was significantly associated with hip fracture risk in women (hazard ratio, 1.12, 95 % CI, 1.001-1.25), but not in men. In the subcohort with BMD measurement, increased urine albumin levels were significantly associated with decreased total hip BMD in men (-0.009 g calcium/cm(2) (-0.017, -0.001); p = 0.04), but not in women. CONCLUSIONS: In older women, albuminuria is associated with a small, but statistically significant, increased risk of hip fracture independent of other explanatory factors. No such risk appears to be present in men, although their total hip BMD is lower in association with albuminuria.