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1.
J Frailty Aging ; 11(1): 12-17, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35122085

RESUMO

BACKGROUND: Mobility limitation is a component of frailty that shares a bidirectional relationship with cardiovascular disease (CVD). Data are limited on the role of established CVD prevention therapies, such as aspirin, for prevention of frailty and mobility limitation. OBJECTIVES: Examine the association between long-term aspirin use and walking speed. DESIGN, SETTING, PARTICIPANTS: Prospective cohort of 14,315 men who participated in the Physicians' Health Study I, a completed randomized controlled trial of aspirin (1982-1988), with extended post-trial follow-up. MEASUREMENTS: Annual questionnaires collected data on aspirin use, lifestyle and other factors. Average annual aspirin use was categorized for each participant: ≤60 days/year and >60 days/year. Mobility was defined according to self-reported walking pace, categorized as: don't walk regularly (reference), easy/casual <2mph, normal ≥2-2.9mph, or brisk/very brisk ≥3mph. Propensity scoring balanced covariates between aspirin categories. Multinomial logistic regression models estimated odds of being in each self-reported walking category. RESULTS: Mean age was 70±8 years; mean aspirin use 11 years. There were 2,056 (14.3%) participants who reported aspirin use ≤60 days/year. Aspirin use >60 days/year was associated with drinking alcohol, smoking, hypertension, heart disease and stroke, while ≤60 days/year was associated with anticoagulation use and bleeding history. In all, 13% reported not walking regularly, 12% walked <2 mph, 44% walked ≥2-2.9 mph, and 31% walked ≥3 mph. After propensity score adjustment, regular aspirin use was associated with a faster walking speed. Odds ratios (95% confidence intervals) were 1.16 (0.97 to 1.39), 1.24 (1.08 to 1.43), and 1.40 (1.21 to 1.63) for <2 mph, ≥2-2.9 mph and ≥3 mph, respectively, compared to not walking regularly (p-trend<0.001). CONCLUSIONS: In this cohort of older men, long-term aspirin use is associated with a greater probability of faster walking speed later in life.


Assuntos
Médicos , Velocidade de Caminhada , Idoso , Aspirina , Humanos , Masculino , Estudos Prospectivos , Autorrelato
2.
J Frailty Aging ; 9(4): 226-231, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32996559

RESUMO

BACKGROUND: 90-day mortality and rehospitalizations are important hospital quality metrics. Biomarkers that predict these outcomes among malnourished hospitalized patients could identify those at risk and help direct care plans. OBJECTIVES: To identify biomarkers that predict 90-day (primary) and 30-day (secondary) mortality or nonelective rehospitalization. DESIGN AND PARTICIPANTS: An analysis of the ability of biomarkers to predict 90- and 30-day mortality and rehospitalization among malnourished hospitalized patients. SETTING: 52 blood biomarkers were measured in 193 participants in NOURISH, a randomized trial that determined the effects of a nutritional supplement on 90-day readmission and death in patients >65 years. Composite outcomes were defined as readmission or death over 90-days or 30-days. Univariate Cox Proportional Hazards models were used to select best predictors of outcomes. Markers with the strongest association were included in multivariate stepwise regression. Final model of hospital readmission or death was derived using stepwise selection. MEASUREMENTS: Nutritional, inflammatory, hormonal and muscle biomarkers. RESULTS: Mean age was 76 years, 51% were men. In univariate models, 10 biomarkers were significantly associated with 90-day outcomes and 4 biomarkers with 30-day outcomes. In multivariate stepwise selection, glutamate, hydroxyproline, tau-methylhistidine levels, and sex were associated with death and readmission within 90-days. In stepwise selection, age-adjusted model that included sex and these 3 amino-acids demonstrated moderate discriminating ability over 90-days (C-statistic 0.68 (95%CI 0.61, 0.75); age-adjusted model that included sex, hydroxyproline and Charlson Comorbidity Index was predictive of 30-day outcomes (C-statistic 0.76 (95%CI 0.68, 0.85). CONCLUSIONS: Baseline glutamate, hydroxyproline, and tau-methylhistidine levels, along with sex and age, predict risk of 90-day mortality and nonelective readmission in malnourished hospitalized older patients. This biomarker set should be further validated in prospective studies and could be useful in prognostication of malnourished hospitalized patients and guiding in-hospital care.


Assuntos
Biomarcadores , Desnutrição/mortalidade , Desnutrição/terapia , Readmissão do Paciente/estatística & dados numéricos , Idoso , Suplementos Nutricionais , Feminino , Humanos , Masculino
3.
J Frailty Aging ; 9(1): 57-63, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32150215

RESUMO

BACKGROUND: Human aging is characterized by a chronic, low-grade inflammation suspected to contribute to reductions in skeletal muscle size, strength, and function. Inflammatory cytokines, such as interleukin-6 (IL-6), may play a role in the reduced skeletal muscle adaptive response seen in older individuals. OBJECTIVES: To investigate relationships between circulating IL-6, skeletal muscle health and exercise adaptation in mobility-limited older adults. DESIGN: Randomized controlled trial. SETTING: Exercise laboratory on the Health Sciences campus of an urban university. PARTICIPANTS: 99 mobility-limited (Short Physical Performance Battery (SPPB) ≤9) older adults. INTERVENTION: 6-month structured physical activity with or without a protein and vitamin D nutritional supplement. MEASUREMENTS: Circulating IL-6, skeletal muscle size, composition (percent normal density muscle tissue), strength, power, and specific force (strength/CSA) as well as physical function (gait speed, stair climb time, SPPB-score) were measured pre- and post-intervention. RESULTS: At baseline, Spearman's correlations demonstrated an inverse relationship (P<0.05) between circulating IL-6 and thigh muscle composition (r = -0.201), strength (r = -0.311), power (r = -0.210), and specific force (r = -0.248), and positive association between IL-6 and stair climb time (r = 0.256; P<0.05). Although the training program did not affect circulating IL-6 levels (P=0.69), reductions in IL-6 were associated with gait speed improvements (r = -0.487; P<0.05) in "higher" IL-6 individuals (>1.36 pg/ml). Moreover, baseline IL-6 was inversely associated (P<0.05) with gains in appendicular lean mass and improvements in SPPB score (r = -0.211 and -0.237, respectively). CONCLUSIONS: These findings implicate age-related increases in circulating IL-6 as an important contributor to declines in skeletal muscle strength, quality, function, and training-mediated adaptation. Given the pervasive nature of inflammation among older adults, novel therapeutic strategies to reduce IL-6 as a means of preserving skeletal muscle health are enticing.


Assuntos
Exercício Físico/fisiologia , Interleucina-6/sangue , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Idoso , Humanos , Limitação da Mobilidade
4.
Andrology ; 7(3): 307-314, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30761772

RESUMO

BACKGROUND: The relation between endogenous testosterone concentrations and myocardial mass and function remains incompletely understood. OBJECTIVES: To determine the cross-sectional association between endogenous hormone levels with cardiac magnetic resonance measures of myocardial mass, structure, and function in community-dwelling men across a wide age range. METHODS: A total of 720 men from the Framingham Heart Study Offspring Cohort (age range 37-82, mean = 59.6 years) who underwent cardiac magnetic resonance imaging and had hormone levels measured. Total testosterone (measured using liquid chromatography-tandem mass spectrometry), sex hormone-binding globulin (measured using an immunofluorometric assay), and calculated free testosterone levels were assessed in male participants of the Framingham Heart Study Offspring Cohort at examination 7. Cardiac magnetic resonance imaging was performed between examinations 7 and 8 (2002-2006). RESULTS: Age-adjusted linear regression models showed statistically significant association between total testosterone levels and left ventricular mass (p = 0.009), left ventricular mass index (p = 0.006), cardiac output (p = 0.001), and main pulmonary artery diameter (p = 0.008); the association between total testosterone and these cardiac magnetic resonance measures was weak and was not significant after adjustment for established risk factors-age, body mass index, diabetes, and hypertension. Furthermore, calculated free testosterone level was not significantly associated with any measure of myocardial mass or function. Sex hormone-binding globulin level was significantly associated with left ventricular mass (p = 0.002), left ventricular mass index (p = 0.004), cardiac output (p = 0.003), left ventricular ejection fraction (p = 0.039), and main pulmonary artery diameter (p = 0.042) in age-adjusted models; these associations were also rendered non-significant after adjusting for cardiovascular risk factors. CONCLUSIONS: Neither testosterone nor sex hormone-binding globulin levels in men are associated significantly with myocardial mass and function independent of established cardiovascular risk factors.


Assuntos
Coração/fisiologia , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/sangue , Estudos de Coortes , Coração/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Fatores de Risco
5.
Arch Osteoporos ; 13(1): 124, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30421141

RESUMO

In clinical practice, the frequency of patients achieving improved T-scores and the expected change in bone mineral density (BMD) according to osteoporosis drugs is unknown. We found that osteoporosis medications infrequently achieve improved femoral neck T-scores over 1.2 years. BMD increases were more often seen with IV bisphosphonates and denosumab. PURPOSE: To determine the frequency of osteoporosis patients achieving improvement in T-scores and quantify the change in bone mineral density (BMD) over time according to osteoporosis medication use. METHODS: The study included all patients receiving clinical care at United Osteoporosis Centers, Gainesville, GA, 1995-2015, who had at least two measures of femoral neck BMD (N = 1232). We evaluated successive pairs of BMD tests to describe the distribution of transitions between T-score categories. Generalized estimating equations were used to estimate %BMD change between successive pairs of BMD tests according to osteoporosis medication, adjusted for age, sex, height, weight, baseline BMD, previous fracture, and follow-up time. RESULTS: Mean (±SD) age was 68 (±10) years, and 90% of patients were women. Mean baseline T-score was - 2.04 (± 0.85). In total, 1232 patients had 4918 pairs of successive BMD tests, with a mean 1.2 years (± 0.9) between assessments. Frequency of transition to an improved T-score category was 41% when prior T-score ≤ - 3.5, and 15% when prior T-score - 1.99 to - 1.50. Most individuals (69%) remained in the same T-score category. BMD increased 0.54% (95% CI 0.23-0.85%) with IV bisphosphonates and 1.23% (95% CI 0.56-1.90%) with denosumab, whereas no significant change was seen with oral bisphosphonates, teriparatide, or raloxifene. CONCLUSIONS: Osteoporosis patients are unlikely to improve femoral neck T-scores over 1.2 years. Additional studies are needed to determine the optimal time to repeat BMD testing while receiving osteoporosis treatment and to determine whether fracture risk is reduced in patients who achieve target T-scores.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Osteoporose/fisiopatologia , Idoso , Denosumab/uso terapêutico , Difosfonatos/uso terapêutico , Feminino , Colo do Fêmur/fisiopatologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Cloridrato de Raloxifeno/uso terapêutico , Teriparatida/uso terapêutico , Fatores de Tempo , Resultado do Tratamento
6.
J Nutr Health Aging ; 22(1): 1-7, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29300415

RESUMO

OBJECTIVES: To examine the potential association between serum 25(OH) vitamin D and the performance on the Short Physical Performance Battery (SPPB) including the sub-components; five repeated chair stands test, 4 meters walk test and balance in older mobility-limited community-dwelling men and women. DESIGN: A cross sectional study was performed in American and Swedish subjects who were examined for potential participation in a combined exercise and nutrition intervention trial. Logistic regression analysis and linear regression analyses were performed to evaluate the association for 25(OH)D with the overall score on the SBBP, chair stand, gait speed and balance. PARTICIPANTS: Community-dwelling (mean age 77.6 ± 5.3 years) mobility limited American (n=494) and Swedish (n=116) females (59%) and males. MEASUREMENTS: The SPPB (0-12 points) includes chair stand (s), gait speed (m/s) and a balance test. Mobility limitation i.e., SPPB score ≤ 9 was an inclusion criterion. A blood sample was obtained to measure serum 25(OH)vitamin D concentrations. RESULTS: No clear association of 25(OH)D with SPPB scores was detected either when 25(OH)D was assessed as a continuous variable or when categorized according to serum concentrations of <50, 50-75 or <75 nmol/L. However, when analyzing the relationship between 25(OH)D and seconds to perform the chair stands, a significant quadratic relationship was observed. Thus, at serum levels of 25(OH)D above 74 nmol/L, higher concentrations appeared to be advantageous for the chair stand test, whereas for serum levels below 74 nmol/L this association was not observed. CONCLUSION: This cross- sectional study lacked clear association between serum 25(OH)D and physical performance in mobility limited adults. A potentially interesting observation was that at higher serum levels of 25(OH)D a better performance on the chair stand test was indicated.


Assuntos
Desempenho Físico Funcional , Vitamina D/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos Transversais , Suplementos Nutricionais , Exercício Físico , Feminino , Humanos , Vida Independente , Masculino , Limitação da Mobilidade , Estado Nutricional , Equilíbrio Postural , Suécia , Estados Unidos , Vitamina D/sangue , Vitaminas , Velocidade de Caminhada
7.
Andrology ; 6(1): 29-36, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28950424

RESUMO

In a subset of men, sarcopenia and physical dysfunction occur due to destabilization of the neuromuscular junction (NMJ), which is manifested by elevated serum concentrations of C-terminal agrin fragment (CAF). Testosterone administration improves physical function in some studies; however, its effects on serum circulating CAF concentrations remain unknown. Here we evaluate the effects of testosterone administration on circulating CAF levels in mobility-limited men with low testosterone aged 65 or older participating in the Testosterone in Older Men with Mobility Limitations (TOM) Trial. We analyzed the difference in change in serum CAF levels between testosterone and placebo groups, as well as its association with muscle strength and physical function. Association of change in serum CAF levels with serum total (TT) and free testosterone (FT) was also evaluated. Men randomized to testosterone experienced significant improvement in muscle strength and physical function (assessed by loaded stair-climbing power). However; testosterone administration was not associated with a reduction in serum CAF levels (effect size = -50.3 pm; 95% CI = -162.1 to 61.5 pm; p = 0.374); there was no association between changes in CAF levels with changes in TT (p = 0.670) or FT (p = 0.747). There was no association between changes in serum CAF levels with improvement in either muscle strength or stair-climbing power. In conclusion, testosterone treatment in mobility-limited older men with low to low-normal testosterone levels did not reduce serum CAF levels. Additionally, testosterone-induced improvements in muscle strength and physical function were not associated with changes in serum CAF concentrations. These findings suggest that improvement in physical function with testosterone replacement in older men with mobility limitations and elevated CAF levels is mediated by mechanisms other than stabilization of the NMJ.


Assuntos
Agrina/sangue , Androgênios/uso terapêutico , Limitação da Mobilidade , Fragmentos de Peptídeos/sangue , Sarcopenia/tratamento farmacológico , Testosterona/uso terapêutico , Idoso , Envelhecimento/patologia , Método Duplo-Cego , Humanos , Masculino , Força Muscular/efeitos dos fármacos
8.
Andrology ; 6(1): 151-157, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28981994

RESUMO

There is substantial inter-individual variability in serum testosterone levels in hypogonadal men treated with testosterone gels. We aimed to elucidate participant-level factors that contribute to inter-individual variability in testosterone levels during testosterone therapy. An exploratory aim was to determine whether polymorphisms in genes encoding testosterone-metabolizing enzymes could explain the variation in on-treatment testosterone concentrations in men who were randomized to testosterone arm in TOM Trial. We used data from three randomized trials that used 1% transdermal testosterone gels and had testosterone levels measured 2-4 weeks after randomization for dose adjustment: Testosterone in Older Men with Mobility Limitation (TOM), Effects of Testosterone on Pain Perception (TAP), and Effects of Testosterone on Atherosclerosis Progression (TEAAM). Forty-seven percent, 38%, and 9% of participants in TAP, TEAAM, and TOM trials, respectively, failed to raise testosterone levels >400 ng/dL; 6, 8, and 30% of participants had on-treatment testosterone levels >1000 ng/dL. Even after dose adjustment, there was substantial variation in on-treatment levels at subsequent study visits. Baseline characteristics (age, height, weight, baseline testosterone, SHBG, hematocrit, and creatinine) accounted for only a small fraction of the variance (<8%). Polymorphisms in SHBG and AKR1C3 genes were suggestively associated with on-treatment testosterone levels. To conclude, baseline participant characteristics account for only a small fraction of the variance in on-treatment testosterone levels investigated. Multiple dose titrations are needed to maintain on-treatment testosterone levels in the target range. The role of SHBG and AKR3C1 polymorphisms as contributors to variations in on-treatment testosterone levels should be investigated.


Assuntos
Androgênios/administração & dosagem , Eunuquismo/tratamento farmacológico , Testosterona/administração & dosagem , Testosterona/sangue , Administração Cutânea , Adulto , Idoso , Membro C3 da Família 1 de alfa-Ceto Redutase/genética , Géis , Terapia de Reposição Hormonal/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Ensaios Clínicos Controlados Aleatórios como Assunto , Globulina de Ligação a Hormônio Sexual/genética
9.
Andrology ; 6(1): 64-73, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29280355

RESUMO

Testosterone dose-dependently increases appendicular muscle mass. However, the effects of testosterone administration on the core muscles of the trunk and the pelvis have not been evaluated. The present study evaluated the effects of testosterone administration on truncal and pelvic muscles in a dose-response trial. Participants were young healthy men aged 18-50 years participating in the 5α-Reductase (5aR) Trial. All participants received monthly injections of 7.5 mg leuprolide acetate to suppress endogenous testosterone production and weekly injections of 50, 125, 300, or 600 mg of testosterone enanthate and were randomized to receive either 2.5 mg dutasteride (5aR inhibitor) or placebo daily for 20 weeks. Muscles of the trunk and the pelvis were measured at baseline and the end of treatment using 1.5-Tesla magnetic resonance imaging. The dose effect of testosterone on changes in the psoas major muscle area was the primary outcome; secondary outcomes included changes in paraspinal, abdominal, pelvic floor, ischiocavernosus, and obturator internus muscles. The association between changes in testosterone levels and muscle area was also assessed. Testosterone dose-dependently increased areas of all truncal and pelvic muscles. The estimated change (95% confidence interval) of muscle area increase per 100 mg of testosterone enanthate dosage increase was 0.622 cm2 (0.394, 0.850) for psoas; 1.789 cm2 (1.317, 2.261) for paraspinal muscles, 2.530 cm2 (1.627, 3.434) for total abdominal muscles, 0.455 cm2 (0.233, 0.678) for obturator internus, and 0.082 cm2 (0.003, 0.045) for ischiocavernosus; the increase in these volumes was significantly associated with the changes in on-treatment total and free serum testosterone concentrations. In conclusion, core muscles of the trunk and pelvis are responsive to testosterone administration. Future trials should evaluate the potential role of testosterone administration in frail men who are predisposed to falls and men with pelvic floor dysfunction.


Assuntos
Androgênios/administração & dosagem , Composição Corporal/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Testosterona/administração & dosagem , Adolescente , Adulto , Método Duplo-Cego , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pelve , Tronco , Adulto Jovem
10.
J Nutr Health Aging ; 21(9): 936-942, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29083433

RESUMO

OBJECTIVES: The interactions between nutritional supplementation and physical activity on changes in physical function among older adults remain unclear. The primary objective of this study was to examine the impact of nutritional supplementation plus structured physical activity on 400M walk capacity in mobility-limited older adults across two sites (Boston, USA and Stockholm, Sweden). DESIGN: All subjects participated in a physical activity program (3x/week for 24 weeks), involving walking, strength, balance, and flexibility exercises. Subjects were randomized to a daily nutritional supplement (150kcal, 20g whey protein, 800 IU vitamin D) or placebo (30kcal, non-nutritive). SETTING: Participants were recruited from urban communities at 2 field centers in Boston MA USA and Stockholm SWE. PARTICIPANTS: Mobility-limited (Short Physical Performance Battery (SPPB) ≤9) and vitamin D insufficient (serum 25(OH) D 9 - 24 ng/ml) older adults were recruited for this study. MEASUREMENTS: Primary outcome was gait speed assessed by the 400M walk. RESULTS: 149 subjects were randomized into the study (mean age=77.5±5.4; female=46.3%; mean SPPB= 7.9±1.2; mean 25(OH)D=18.7±6.4 ng/ml). Adherence across supplement and placebo groups was similar (86% and 88%, respectively), and was also similar across groups for the physical activity intervention (75% and 72%, respectively). Both groups demonstrated an improvement in gait speed with no significant difference between those who received the nutritional supplement compared to the placebo (0.071 and 0.108 m/s, respectively (p=0.06)). Similar effects in physical function were observed using the SPPB. Serum 25(OH)D increased in supplemented group compared to placebo 7.4 ng/ml versus 1.3 ng/ml respectively. CONCLUSION: Results suggest improved gait speed following physical activity program with no further improvement with added nutritional supplementation.


Assuntos
Suplementos Nutricionais/estatística & dados numéricos , Exercício Físico/fisiologia , Avaliação Nutricional , Caminhada/fisiologia , Idoso , Exercício Físico/psicologia , Feminino , Humanos , Masculino
11.
Andrology ; 5(5): 889-897, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28704587

RESUMO

Animal data shows that testosterone administration increases the volume of some parenchymal organs. However, the effects of exogenous testosterone on solid abdominal organs in humans remain unknown. The present study evaluated the effects of testosterone administration on the volume of liver, spleen and kidneys in a dose-response trial. Young healthy men aged 18-50 years participating in the 5α-Reductase (5aR) Trial. All participants received monthly injections of 7.5 mg leuprolide acetate to suppress endogenous testosterone secretion and weekly injections of 50, 125, 300 or 600 mg of testosterone enanthate, and were randomized to receive either 2.5 mg dutasteride (5 α-reductase inhibitor) or placebo daily for 20 weeks. Liver, spleen and kidney volumes were measured at baseline and the end of treatment using 1.5-Tesla magnetic resonance imaging. The dose-effect of testosterone on changes in the volume of parenchymal organs was evaluated by linear regression model. The association between changes in total testosterone (TT) levels and changes in organ volumes were assessed. Testosterone administration increased liver volume dose-dependently (17.4 cm3 per 100 mg of weekly testosterone enanthate; p = 0.031); the increase in liver volume was positively associated with changes in TT levels (R2  = 0.08, p = 0.024). A dose-dependent, but non-significant, increase in kidney volumes was also seen. Inclusion of dutasteride use into the models showed an independent association of randomization to dutasteride group with liver volume increase. In conclusion, Testosterone administration increased the liver volume in a dose-dependent manner. The potential changes in parenchymal organs should be considered when interpreting apparent changes in lean mass in response to anabolic interventions.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/farmacologia , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Baço/efeitos dos fármacos , Testosterona/análogos & derivados , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/administração & dosagem , Adulto , Composição Corporal , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/efeitos dos fármacos , Testosterona/administração & dosagem , Testosterona/farmacologia , Adulto Jovem
12.
J Endocrinol Invest ; 38(4): 455-61, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25430996

RESUMO

PURPOSE: To determine the dose-dependent effects of testosterone administration on cognition in women with low testosterone levels. METHODS: 71 hysterectomized women with or without oophorectomy with total testosterone <31 ng/dl and/or free testosterone <3.5 pg/ml received a standardized transdermal estradiol regimen during the 12-week run-in period and were then randomized to receive weekly intramuscular injections of placebo, 3, 6.25, 12.5, or 25 mg testosterone enanthate for 24 weeks. Total testosterone was measured in serum by LC-MS/MS, and free testosterone levels were measured by equilibrium dialysis. Cognitive function was evaluated using a comprehensive battery of standardized neuropsychological tests at baseline and 24 weeks. RESULTS: 46 women who had baseline and end-of-treatment cognitive function data constituted the analytic sample. The five groups were similar at baseline. Mean on-treatment nadir total testosterone concentrations were 15, 89, 98, 134, and 234 ng/dl in the placebo, 3, 6.25, 12.5, and 25 mg groups, respectively. No significant changes in spatial ability, verbal fluency, verbal memory, or executive function were observed in any treatment arm compared to placebo even after adjustment for baseline cognitive function, age, and education. Multiple regression analysis did not show any significant relation between changes in testosterone concentrations and change in cognitive function scores. CONCLUSION: Short-term testosterone administration over a wide range of doses for 24 weeks in women with low testosterone levels was neither associated with improvements nor worsening of cognitive function.


Assuntos
Cognição/efeitos dos fármacos , Função Executiva/efeitos dos fármacos , Histerectomia , Testosterona/metabolismo , Testosterona/farmacologia , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Estradiol/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Ovariectomia , Testosterona/administração & dosagem , Resultado do Tratamento
13.
Clin Endocrinol (Oxf) ; 80(2): 277-82, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23746309

RESUMO

OBJECTIVE: Circulating testosterone, oestradiol and oestrone concentrations vary considerably between men. Although a substantial proportion of this variation may be attributed to morbidity and behavioural factors, these cannot account for its entirety, suggesting genetic inheritance as a potential additional determinant. The analysis described here was intended to estimate the heritability of male circulating total testosterone (TT), calculated free testosterone (cFT), oestrone (E1), oestradiol (E2) and sex hormone binding globulin (SHBG), along with the genetic correlation between these factors. DESIGN: Cross-sectional, observational analysis of data from male members of the Offspring and Generation 3 cohorts of the Framingham Heart Study. Data were collected in the years 1998-2005. PARTICIPANTS: A total of 3367 community-dwelling men contributed to the analysis, including 1066 father/son and 1284 brother pairs among other family relationships. MEASUREMENTS: Levels of serum sex steroids (TT, E1 and E2) were measured by liquid chromatography-tandem mass spectrometry, SHBG by immunofluorometric assay and cFT by mass action equation. Heritability was obtained using variance components analysis with adjustment for covariates including age, diabetes mellitus, body mass index and smoking status. RESULTS: Age-adjusted heritability estimates were 0·19, 0·40, 0·40, 0·30 and 0·41 for cFT, TT, E1, E2 and SHBG, respectively. Adjustment for covariates did not substantially attenuate these estimates; SHBG-adjusted TT results were similar to those obtained for cFT. Genetic correlation coefficients (ρG ) indicated substantial genetic association between TT and cFT (ρG = 0·68), between TT and SHBG (pG = 0·87), between E1 and E2 (ρG = 0·46) and between TT and E2 (ρG = 0·48). CONCLUSION: Circulating testosterone, oestradiol and oestrone concentrations exhibit substantial heritability in adult men. Significant genetic association between testosterone and oestrogen levels suggests shared genetic pathways.


Assuntos
Estradiol/sangue , Estrona/sangue , Genes Ligados ao Cromossomo Y/genética , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Adulto , Cromatografia Líquida , Estudos Transversais , Saúde da Família , Fluorimunoensaio , Estudos de Associação Genética/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem
14.
Andrology ; 1(6): 913-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24106072

RESUMO

Phosphodiesterase-5-inhibitors, such as sildenafil, increase intracavernosal cyclic guanosine monophosphate levels, which results in corporal smooth muscle relaxation and penile erection. Here, we determined the effects of sildenafil administration on the hypothalamic-pituitary-gonadal axis in men with erectile dysfunction and low testosterone levels. The Testosterone and Erectile Dysfunction trial (ClinicalTrials.gov # NCT00512707) initially administered an optimized dose of sildenafil to 140 men, aged 40-70 years with erectile dysfunction, low serum total testosterone (<11.4 nmol/L; 330 ng/dL) and/or free testosterone (<173 pmol/L; 50 pg/mL) over 3-7 weeks. Sex steroids and gonadotropins were measured at baseline and after sildenafil optimization in a longitudinal study without a separate control group. Serum testosterone, dihydrotestosterone (DHT) and oestrogens were measured using liquid chromatography-tandem mass spectrometry. Administration of an optimized dose of sildenafil was associated with mean increases of 3.6 nmol/L (103 ng/dL; p < 0.001) and 110 pmol/L (31.7 pg/mL; p < 0.001) in total and free testosterone levels respectively. This was accompanied by parallel increases in serum DHT (0.17 nmol/L; 4.9 ng/dL; p < 0.001) and oestradiol (14 pmol/L; 3.7 pg/mL; p < 0.001) and significant suppression of luteinizing hormone (change -1.3 units/L; p = 0.003) levels, suggesting a direct effect at the testicular level. Androstenedione and oestrone increased by 1.3 nmol/L (38 ng/dL; p = 0.011) and 10.7 pmol/L (2.9 pg/mL; p = 0.012), respectively, supporting a possible effect of sildenafil on adrenal steroidogenesis. In conclusion, sildenafil administration was associated with increased testosterone levels likely ascribable to a direct effect on the testis.


Assuntos
Inibidores da Fosfodiesterase 5/uso terapêutico , Piperazinas/uso terapêutico , Sulfonas/uso terapêutico , Testículo/efeitos dos fármacos , Testosterona/sangue , Adulto , Idoso , Androstenodiona/sangue , Di-Hidrotestosterona/sangue , Disfunção Erétil/sangue , Disfunção Erétil/tratamento farmacológico , Estradiol/sangue , Estrona/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Purinas/uso terapêutico , Citrato de Sildenafila
15.
Andrology ; 1(3): 475-82, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23494931

RESUMO

The relationship between testosterone, well-being and mood is poorly understood. We investigated the effect of testosterone supplementation on mood, well-being, and self-reported health in men with erectile dysfunction (ED) and low serum testosterone levels. This was a randomized, double-blind, placebo-controlled trial (ClinicalTrials.gov registration number NCT00512707), in which 140 men, 40-70 years, with ED and low serum testosterone levels were first optimized on sildenafil alone for 3-7 weeks and then randomized to receive either sildenafil plus testosterone gel (n = 70) or sildenafil plus placebo (n = 70) gel for 14 weeks. Using multiple imputations and generalized linear regression, we compared psychological changes in well-being, evaluated by the Psychological General Well-Being Index, and mood, evaluated by Derogatis Affects Balance Scale. Mood and well-being scores were similar between the two groups at baseline and did not substantially change during the administration of sildenafil or after randomization to testosterone. Our findings show that the addition of testosterone to sildenafil in men with ED and low serum testosterone levels was not associated with improvement in either well-being or mood.


Assuntos
Afeto/efeitos dos fármacos , Disfunção Erétil/prevenção & controle , Testosterona/administração & dosagem , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Qualidade de Vida , Testosterona/farmacologia
16.
Osteoporos Int ; 23(6): 1779-87, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21901477

RESUMO

UNLABELLED: People with both HIV and hepatitis C are more likely than those with HIV alone to have wrist, hip, and spine fractures. We compared hip strength between HIV/HCV-co-infected men and healthy men and found that HIV/HCV-co-infected men had decreased hip strength due to lower lean body mass. INTRODUCTION: Hepatitis C co-infection is a risk factor for fragility fracture among HIV-infected populations. Whether bone strength is compromised in HIV/HCV-co-infected patients is unknown. METHODS: We compared dual-energy x-ray absorptiometry (DXA)-derived hip geometry, a measure of bone strength, in 88 HIV/HCV-co-infected men from the Johns Hopkins HIV Clinic to 289 men of similar age and race and without HIV or HCV from the Boston Area Community Health Survey/Bone Survey. Hip geometry was assessed at the narrow neck, intertrochanter, and shaft using hip structural analysis. Lean body mass (LBM), total fat mass (FM), and fat mass ratio (FMR) were measured by whole-body DXA. Linear regression was used to identify body composition parameters that accounted for differences in bone strength between cohorts. RESULTS: HIV/HCV-co-infected men had lower BMI, LBM, and FM and higher FMR compared to controls (all p < 0.05). At the narrow neck, significant differences were observed between HIV/HCV-co-infected men and controls in bone mineral density, cross-sectional area, section modulus, buckling ratio, and centroid position. After adjustment for race, age, smoking status, height, and weight, only buckling ratio and centroid position remained significantly different between cohorts (all p < 0.05). Substituting LBM, FM, and FMR for weight in the multivariate model revealed that differences in LBM, but not FM or FMR, accounted for differences in all narrow neck parameters between cohorts, except buckling ratio and centroid position. CONCLUSION: HIV/HCV-co-infected men have compromised hip strength at the narrow neck compared to uninfected controls, which is attributable in large part to lower lean body mass.


Assuntos
Infecções por HIV/complicações , Hepatite C/complicações , Articulação do Quadril/patologia , Absorciometria de Fóton , Adulto , Idoso , Composição Corporal , Densidade Óssea , Estudos de Casos e Controles , Estudos Transversais , Articulação do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
17.
Osteoporos Int ; 22(10): 2645-54, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21210082

RESUMO

UNLABELLED: The relative importance of various contributors to racial/ethnic variation in BMC/BMD is not established. Using population-based data, we determined that body composition differences (specifically skeletal muscle and fat mass) are among the strongest contributors to these variations. INTRODUCTION: Racial/ethnic variation in fracture risk is well documented, but the mechanisms by which such heterogeneity arises are poorly understood. We analyzed data from black, Hispanic, and white men enrolled in the Boston Area Community Health/Bone (BACH/Bone) Survey to determine the contributions of risk factors to racial/ethnic differences in bone mineral content (BMC) and density (BMD). METHODS: In a population-based study, BMC, BMD, and body composition were ascertained by DXA. Socioeconomic status, health history, and dietary intake were obtained via interview. Hormones and markers of bone turnover were obtained from non-fasting blood samples. Multivariate analyses measured percentage reductions in estimated racial/ethnic differences in BMC/BMD, accompanying the successive removal of covariates from linear regression models. RESULTS: Black men demonstrated greater BMC than their Hispanic and white counterparts. At the femoral neck, adjustment for covariables was sufficient to reduce these differences by 46% and 35%, respectively. While absolute differences in BMC were smaller at the distal radius than femoral neck, the proportionate reductions in racial/ethnic differences after covariable adjustment were comparable or greater. Multivariate models provided evidence that lean and fat mass, serum 25(OH)D, osteocalcin, estradiol, and aspects of socioeconomic status influence the magnitude of racial/ethnic differences in BMC, with lean and fat mass providing the strongest effects. Results for BMD were similar, but typically of lesser magnitude and statistical significance. CONCLUSIONS: These cross-sectional analyses demonstrate that much of the racial/ethnic heterogeneity in measures of bone mass and density can be accounted for through variation in body composition, diet, and socio-demographic factors.


Assuntos
População Negra , Densidade Óssea/fisiologia , Hispânico ou Latino , População Branca , Absorciometria de Fóton , Adulto , Idoso , Androgênios/sangue , Composição Corporal/fisiologia , Estudos Transversais , Estrogênios/sangue , Colo do Fêmur/diagnóstico por imagem , Nível de Saúde , Humanos , Estilo de Vida/etnologia , Masculino , Pessoa de Meia-Idade , Rádio (Anatomia)/diagnóstico por imagem , Fatores de Risco , Fatores Socioeconômicos
18.
Osteoporos Int ; 20(12): 2035-47, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19319620

RESUMO

SUMMARY: Focus on individual risk factors for osteoporosis could allocate disproportionate attention to trivial relationships. We tested many recognized risk factors of osteoporosis for their association with bone mineral density (BMD) in multivariate models among men. Lean mass accounted for the most variance, with substantially less accounted for by demographic, strength, and health factors. INTRODUCTION: Osteoporosis in men has gained recognition as a public health problem, generating an interest in the search for risk factors. Isolation of individual risk factors could allocate disproportionate attention to relationships that may be of limited consequence. METHODS: The Boston Area Community Health/Bone (BACH/Bone) Survey is a population-based study of randomly selected community-dwelling men (age, 30-79 years). BMD and lean mass were measured by dual X-ray absorptiometry. Socioeconomic status, health history, and lifestyle factors were obtained via interview. Hormone levels and markers of bone turnover were obtained from non-fasting blood samples. Multivariate analyses measured relative contributions of covariates to femoral neck (hip), one-third distal radius (wrist), and lumbar spine BMD. RESULTS: Factors positively associated with BMD in multivariate models at the three sites were black race and appendicular lean mass. Asthma was consistently negatively associated. Various other risk factors also contributed significantly to each of the individual sites. R (2) values for the hip, wrist, and spine were 41%, 30%, and 24%, respectively. Lean mass accounted for the most explained variance at all three sites. CONCLUSIONS: These data emphasize the limitation of focusing on individual risk factors and highlight the importance of potentially modifiable lean mass in predicting BMD.


Assuntos
Densidade Óssea/fisiologia , Osteoporose/etiologia , Absorciometria de Fóton/métodos , Adulto , Idoso , Biomarcadores/sangue , Composição Corporal , Métodos Epidemiológicos , Colo do Fêmur/fisiopatologia , Humanos , Estilo de Vida , Vértebras Lombares/fisiopatologia , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Rádio (Anatomia)/fisiopatologia , Classe Social
19.
Osteoporos Int ; 20(2): 245-55, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18548306

RESUMO

UNLABELLED: There are few data on the skeletal health of Hispanic men. We observed differences in vitamin D deficiency and low BMD between Hispanic ethnic subgroups that persisted with adjustment for risk factors. Our data indicate a substantial burden of low BMD and vitamin D deficiency among Hispanic men. INTRODUCTION: Disparities within ethnic groups are generally ignored, but in evolving populations they may have implications for public health. We examined ethnic variation in serum 25-hydroxyvitamin D [25(OH)D] and bone mineral density (BMD) among Hispanic American men. METHODS: Three hundred and fifty-eight Hispanic males 30 to 79 years of age were studied. Logistic regression models assessed variation in odds of vitamin D deficiency (<20 ng/mL) and low BMD (T-score<-1) by ethnicity, with and without adjustment for risk factors (age, smoking, occupation, physical activity, body mass index, and sunlight exposure). RESULTS: Vitamin D deficiency was most common among Puerto Rican (26%), compared with Dominican (21%), Central American (11%), and South American (9%) men. Percentages with low BMD were: South American (44%), Puerto Rican (34%), Dominican (29%), and Central American (23%). Adjustment for age and risk factors failed to account for Hispanic subgroup differences in vitamin D deficiency and low BMD. Population estimates indicate a substantial burden of low BMD and vitamin D deficiency among Hispanic men. CONCLUSIONS: Our findings underscore the importance of examining the skeletal health of Hispanic subgroups, and suggest that a considerable number of Hispanic men may be at elevated risk of fracture and vitamin D deficiency.


Assuntos
Hispânico ou Latino , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/etnologia , Vitamina D/análogos & derivados , Adulto , Idoso , Biomarcadores/sangue , Densidade Óssea , Estudos Transversais , Fraturas Ósseas/etiologia , Humanos , Modelos Logísticos , Masculino , Massachusetts , Pessoa de Meia-Idade , Prevalência , Risco , Vitamina D/sangue , Deficiência de Vitamina D/fisiopatologia
20.
Osteoporos Int ; 19(3): 277-87, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18038245

RESUMO

UNLABELLED: Data on bone architecture in diverse male populations are limited. We examined proximal femur geometry in 1,190 black, Hispanic, and white men. Cross-sectional analyses indicate greatest bone strength among black men, and greater age-related differences in bone strength among Hispanic men than other subjects at the narrow neck and intertrochanter regions of the proximal femur. INTRODUCTION: Although race/ethnic differences in bone mass are well-documented, less is known about differences in bone architecture. We examined proximal femur geometry in a diverse, randomly-sampled population of 1,190 community-dwelling men (age 30-79 y). METHODS: Dual X-ray absorptiometry scans were obtained for 355 black, 394 Hispanic, and 441 white subjects. Measures were obtained for the narrow neck (NN), intertrochanter (IT) and shaft regions of the proximal femur via hip structural analysis. Analyses considered bone mineral density (BMD, g/cm2), outer diameter (cm), cross-sectional area (CSA, cm2), section modulus (Z, cm3), and buckling ratio (BR). Results were adjusted for height, weight and physical activity level. RESULTS: Black subjects exhibited greater age-specific BMD, CSA and Z, than their white counterparts. For instance, at age 50 y, NN BMD was approximately 11% higher among black men (p < 0.001). Hispanic men exhibited sharper age-related differences in NN and IT BMD than did others. IT BMD, for instance, decreased by 2.4% with 10 y age among Hispanic subjects, but had virtually no age trend in others (p < 0.001). CONCLUSIONS: These results imply greater bone strength among black American men than among their white counterparts, and may indicate elevated fracture risk among older Hispanic American subpopulations.


Assuntos
Envelhecimento/etnologia , Envelhecimento/fisiologia , Densidade Óssea/fisiologia , Fêmur/fisiologia , Absorciometria de Fóton , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Envelhecimento/patologia , Estatura/fisiologia , Peso Corporal/fisiologia , Estudos Transversais , Fêmur/anatomia & histologia , Colo do Fêmur/anatomia & histologia , Colo do Fêmur/fisiologia , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , População Branca/estatística & dados numéricos
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