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1.
Geroscience ; 46(4): 3911-3927, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38451433

RESUMO

Large-scale genome-wide association studies (GWAS) strongly suggest that most traits and diseases have a polygenic component. This observation has motivated the development of disease-specific "polygenic scores (PGS)" that are weighted sums of the effects of disease-associated variants identified from GWAS that correlate with an individual's likelihood of expressing a specific phenotype. Although most GWAS have been pursued on disease traits, leading to the creation of refined "Polygenic Risk Scores" (PRS) that quantify risk to diseases, many GWAS have also been pursued on extreme human longevity, general fitness, health span, and other health-positive traits. These GWAS have discovered many genetic variants seemingly protective from disease and are often different from disease-associated variants (i.e., they are not just alternative alleles at disease-associated loci) and suggest that many health-positive traits also have a polygenic basis. This observation has led to an interest in "polygenic longevity scores (PLS)" that quantify the "risk" or genetic predisposition of an individual towards health. We derived 11 different PLS from 4 different available GWAS on lifespan and then investigated the properties of these PLS using data from the UK Biobank (UKB). Tests of association between the PLS and population structure, parental lifespan, and several cancerous and non-cancerous diseases, including death from COVID-19, were performed. Based on the results of our analyses, we argue that PLS are made up of variants not only robustly associated with parental lifespan, but that also contribute to the genetic architecture of disease susceptibility, morbidity, and mortality.


Assuntos
Bancos de Espécimes Biológicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Longevidade , Herança Multifatorial , Humanos , Longevidade/genética , Herança Multifatorial/genética , Reino Unido/epidemiologia , Feminino , Masculino , COVID-19/genética , COVID-19/epidemiologia , Pais , Idoso , Biobanco do Reino Unido
2.
J Gerontol A Biol Sci Med Sci ; 75(7): 1317-1323, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-30869772

RESUMO

BACKGROUND: Lack of consensus on how to diagnose sarcopenia has limited the ability to diagnose this condition and hindered drug development. The Sarcopenia Definitions and Outcomes Consortium (SDOC) was formed to develop evidence-based diagnostic cut points for lean mass and/or muscle strength that identify people at increased risk of mobility disability. We describe here the proceedings of a meeting of SDOC and other experts to discuss strategic considerations in the development of evidence-based sarcopenia definition. METHODS: Presentations and panel discussions reviewed the usefulness of sarcopenia as a biomarker, the analytical approach used by SDOC to establish cut points, and preliminary findings, and provided strategic direction to develop an evidence-based definition of sarcopenia. RESULTS: The SDOC assembled data from eight epidemiological cohorts consisting of 18,831 participants, clinical populations from 10 randomized trials and observational studies, and 2 nationally representative cohorts. In preliminary assessments, grip strength or grip strength divided by body mass index was identified as discriminators of risk for mobility disability (walking speed <0.8 m/s), whereas dual-energy X-ray absorptiometry-derived lean mass measures were not good discriminators of mobility disability. Candidate definitions based on grip strength variables were associated with increased risk of mortality, falls, mobility disability, and instrumental activities of daily living disability. The prevalence of low grip strength increased with age. The attendees recommended the establishment of an International Expert Panel to review a series of position statements on sarcopenia definition that are informed by the findings of the SDOC analyses and synthesis of literature. CONCLUSIONS: International consensus on an evidence-based definition of sarcopenia is needed. Grip strength-absolute or adjusted for body mass index-is an important discriminator of mobility disability and other endpoints. Additional research is needed to develop a predictive risk model that takes into account sarcopenia components as well as age, sex, race, and comorbidities.


Assuntos
Composição Corporal , Índice de Massa Corporal , Força da Mão/fisiologia , Limitação da Mobilidade , Sarcopenia/diagnóstico , Sarcopenia/fisiopatologia , Atividades Cotidianas , Idoso , Consenso , Avaliação da Deficiência , Medicina Baseada em Evidências , Feminino , Humanos , Masculino
3.
J Bone Miner Res ; 33(9): 1560-1567, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29750841

RESUMO

Because several studies have implicated serotonin as a regulator of bone mass, we here explore its potential association on fracture risk and falls, as on bone mineral density (BMD) and muscle strength, in humans. Serum levels of serotonin were analyzed in 950 men (aged 69 to 81 years), participating in the Gothenburg part of the population-based study MrOS Sweden. Men taking selective serotonin reuptake inhibitors (SSRIs) had a mean value of 31.2 µg/L compared with 159.4 µg/L in those not taking SSRIs. SSRI users were excluded from further analysis. During 10-year follow-up, 224 men exhibited fractures, including 97 nonvertebral osteoporotic fractures (57 hip fractures), and 86 vertebral fractures. Serotonin was associated with hip fracture in linear analysis (hazard ratio [HR] = 1.27, 95% confidence interval [CI] 1.03-1.58) and to all fractures in a nonlinear manner, when quintiles of serotonin was included in quadratic terms (HR = 1.12, 95% CI 1.04-1.21). Men in serotonin quintile 5 had, in multivariable analysis, a HR of 2.30 (95% CI 1.31-4.02) for hip fracture and 1.82 (95% CI 1.17-2.85) for nonvertebral fractures compared with men in quintiles 1 to 4. Men in quintile 1 had, in multivariable analysis, a HR of 1.76 (95% CI 1.03-2.99) for nonvertebral fractures compared with men in quintiles 2 to 4. No association was found with vertebral fractures. Individuals in serotonin quintile 1 had higher prevalence of falls compared with quintiles 2 to 5 (odds ratio = 1.90, 95% CI 1.26-2.87). Serotonin was positively associated with hand-grip strength (r = 0.08, p = 0.02) and inversely with hip BMD (r = -0.10, p = 0.003). To assess the association between SSRIs and falls and fractures, the total MrOS Sweden cohort was examined (n = 3014). SSRI users (n = 90) had increased prevalence of falls (16% versus 33%, p = 0.0001) and increased rate of incident fractures (28.0 versus 44.7 per 1000 person-years, p = 0.018). We present novel data showing that high levels of serotonin predict an increased risk for hip fracture and nonvertebral osteoporotic fractures. © 2018 American Society for Bone and Mineral Research.


Assuntos
Fraturas do Quadril/sangue , Fraturas do Quadril/epidemiologia , Fraturas por Osteoporose/sangue , Fraturas por Osteoporose/epidemiologia , Serotonina/sangue , Densidade Óssea , Fraturas do Quadril/fisiopatologia , Humanos , Fraturas por Osteoporose/fisiopatologia , Fatores de Risco , Suécia/epidemiologia
4.
J Am Geriatr Soc ; 66(7): 1276-1283, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29684237

RESUMO

OBJECTIVES: To determine the association of the frailty phenotype with subsequent healthcare costs and utilization. DESIGN: Prospective cohort study (Study of Osteoporotic Fractures (SOF)). SETTING: Four U.S. sites. PARTICIPANTS: Community-dwelling women (mean age 80.2) participating in SOF Year 10 (Y10) examination linked with their Medicare claims data (N=2,150). MEASUREMENTS: At Y10, frailty phenotype defined using criteria similar to those used in the Cardiovascular Health Study frailty phenotype and categorized as robust, intermediate stage, or frail. Participant multimorbidity burden ascertained using claims data. Functional limitations assessed by asking about difficulty performing instrumental activities of daily living. Total direct healthcare costs and utilization ascertained during 12 months after Y10. RESULTS: Mean total annualized cost±standard deviation (2014 dollars) was $3,781±6,920 for robust women, $6,632±12,452 for intermediate stage women, and $10,755 ± 16,589 for frail women. After adjustment for age, site, multimorbidity burden, and cognition, frail women had greater mean total (cost ratio (CR)=1.91, 95% confidence interval (CI)=1.59-2.31) and outpatient (CR=1.55, 95% CI=1.36-1.78) costs than robust women and greater odds of hospitalization (odds ratio (OR)=2.05, 95% CI=1.47-2.87) and a skilled nursing facility stay (OR=3.85, 95% CI=1.88-7.88). There were smaller but significant effects of the intermediate stage category on these outcomes. Individual frailty components (shrinking, poor energy, slowness, low physical activity) were also each associated with higher total costs. Functional limitations partially mediated the association between the frailty phenotype and total costs (CR further adjusted for self-reported limitations=1.32, 95% CI=1.07-1.63 for frail vs robust; CR=1.35, 95% CI=1.18-1.55 for intermediate stage vs robust women). CONCLUSION: Intermediate stage and frail older community-dwelling women had higher subsequent total healthcare costs and utilization after accounting for multimorbidity and functional limitations. Frailty phenotype assessment may improve identification of older adults likely to require costly, extensive care.


Assuntos
Idoso Fragilizado/estatística & dados numéricos , Avaliação Geriátrica/estatística & dados numéricos , Fraturas por Osteoporose/economia , Fraturas por Osteoporose/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Fragilidade , Custos de Cuidados de Saúde , Humanos , Estudos Prospectivos , Fatores de Risco
5.
J Gerontol A Biol Sci Med Sci ; 71(8): 1074-80, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26843186

RESUMO

BACKGROUND: Few studies have examined whether change in cognition is linked to mortality. This study examined the relationship between cognitive trajectories in older age and risk of death. METHODS: We studied community-dwelling, nondemented women aged 65+ (mean age = 71) enrolled in a prospective study of aging and followed up to 25 years. A modified Mini-Mental State Examination (mMMSE) and Trail Making Task Part B (TMTB) were administered at multiple visits during follow-up. We examined the association between cognitive trajectories (analyzed by quintiles) from baseline to age 80 (n = 7,477 for mMMSE and n = 6,503 for TMTB) and all-cause mortality after age 80 using Cox regression models, both unadjusted and adjusted for education, physical activity, alcohol, depression score, current smoking and history of hypertension and diabetes. Cause of death was determined from death certificates, classified as cardiovascular, cancer and other. RESULTS: Women with greater rate of decline were older, less educated, less physically active, had higher depression score and were more likely to have a history of hypertension and diabetes (all p < .01). Participants with the greatest decline (quintile 1) had an increased risk of death (mMMSE hazard ratio [HR] = 1.28; TMTB HR = 1.43] and those with the least decline (quintile 5) had a decreased risk of death (mMMSE HR = 0.73; TMTB HR = 0.61) compared with intermediate decliners (quintiles 2-4). Cognitive trajectories were associated with cardiovascular mortality and other causes of death, but not cancer deaths. CONCLUSIONS: Our study suggests that greater decline in general cognition or executive function is associated with higher rates of mortality in oldest-old women.


Assuntos
Envelhecimento , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/mortalidade , Avaliação Geriátrica , Distribuição por Idade , Idoso , Índice de Massa Corporal , Cognição , Transtornos Cognitivos/diagnóstico , Complicações do Diabetes/mortalidade , Escolaridade , Exercício Físico , Feminino , Seguimentos , Humanos , Hipertensão/mortalidade , Vida Independente , Metanálise como Assunto , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , Fatores de Risco , Fumar/efeitos adversos , Estados Unidos/epidemiologia
6.
J Bone Miner Res ; 29(1): 223-33, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23775829

RESUMO

Several recent studies suggest that obesity may be a risk factor for fracture. The aim of this study was to investigate the association between body mass index (BMI) and future fracture risk at different skeletal sites. In prospective cohorts from more than 25 countries, baseline data on BMI were available in 398,610 women with an average age of 63 (range, 20-105) years and follow up of 2.2 million person-years during which 30,280 osteoporotic fractures (6457 hip fractures) occurred. Femoral neck BMD was measured in 108,267 of these women. Obesity (BMI ≥ 30 kg/m(2) ) was present in 22%. A majority of osteoporotic fractures (81%) and hip fractures (87%) arose in non-obese women. Compared to a BMI of 25 kg/m(2) , the hazard ratio (HR) for osteoporotic fracture at a BMI of 35 kg/m(2) was 0.87 (95% confidence interval [CI], 0.85-0.90). When adjusted for bone mineral density (BMD), however, the same comparison showed that the HR for osteoporotic fracture was increased (HR, 1.16; 95% CI, 1.09-1.23). Low BMI is a risk factor for hip and all osteoporotic fracture, but is a protective factor for lower leg fracture, whereas high BMI is a risk factor for upper arm (humerus and elbow) fracture. When adjusted for BMD, low BMI remained a risk factor for hip fracture but was protective for osteoporotic fracture, tibia and fibula fracture, distal forearm fracture, and upper arm fracture. When adjusted for BMD, high BMI remained a risk factor for upper arm fracture but was also a risk factor for all osteoporotic fractures. The association between BMI and fracture risk is complex, differs across skeletal sites, and is modified by the interaction between BMI and BMD. At a population level, high BMI remains a protective factor for most sites of fragility fracture. The contribution of increasing population rates of obesity to apparent decreases in fracture rates should be explored.


Assuntos
Índice de Massa Corporal , Densidade Óssea , Fraturas Ósseas/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/complicações , Fraturas por Osteoporose/etiologia , Risco
7.
Hum Mol Genet ; 21(21): 4774-80, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22843503

RESUMO

Resistin is a polypeptide hormone that was reported to be associated with insulin resistance, inflammation and risk of type 2 diabetes and cardiovascular disease. We conducted a genome-wide association (GWA) study on circulating resistin levels in individuals of European ancestry drawn from the two independent studies: the Nurses' Health Study (n = 1590) and the Health, Aging and Body Composition Study (n = 1658). Single-nucleotide polymorphisms (SNPs) identified in the GWA analysis were replicated in an independent cohort of Europeans: the Gargano Family Study (n = 659). We confirmed the association with a previously known locus, the RETN gene (19p13.2), and identified two novel loci near the TYW3/CRYZ gene (1p31) and the NDST4 gene (4q25), associated with resistin levels at a genome-wide significant level, best represented by SNP rs3931020 (P = 6.37 × 10(-12)) and SNP rs13144478 (P = 6.19 × 10(-18)), respectively. Gene expression quantitative trait loci analyses showed a significant cis association between the SNP rs3931020 and CRYZ gene expression levels (P = 3.68 × 10(-7)). We also found that both of these two SNPs were significantly associated with resistin gene (RETN) mRNA levels in white blood cells from 68 subjects with type 2 diabetes (both P = 0.02). In addition, the resistin-rising allele of the TYW3/CRYZ SNP rs3931020, but not the NDST4 SNP rs13144478, showed a consistent association with increased coronary heart disease risk [odds ratio = 1.18 (95% CI, 1.03-1.34); P = 0.01]. Our results suggest that genetic variants in TYW3/CRYZ and NDST4 loci may be involved in the regulation of circulating resistin levels. More studies are needed to verify the associations of the SNP rs13144478 with NDST4 gene expression and resistin-related disease.


Assuntos
Estudo de Associação Genômica Ampla , Proteínas de Membrana/genética , Resistina/genética , Sulfotransferases/genética , zeta-Cristalinas/genética , Adulto , Feminino , Expressão Gênica , Humanos , Resistência à Insulina/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas/genética , Resistina/sangue , População Branca/genética
8.
J Bone Miner Res ; 26(3): 530-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20839290

RESUMO

Denosumab, a fully human monoclonal antibody to RANKL, decreases bone remodeling, increases bone density, and reduces fracture risk. This study evaluates the time course and determinants of bone turnover marker (BTM) response during denosumab treatment, the percentage of denosumab-treated women with BTMs below the premenopausal reference interval, and the correlations between changes in BTMs and bone mineral density (BMD). The BTM substudy of the Fracture REduction Evaulation of Denosumab in Osteoporosis every 6 Months (FREEDOM) Trial included 160 women randomized to subcutaneous denosumab (60 mg) or placebo injections every 6 months for 3 years. Biochemical markers of bone resorption (serum C-telopeptide of type I collagen [CTX] and tartrate-resistant acid phosphatise [TRACP-5b]) and bone formation (serum procollagen type I N-terminal propeptide [PINP] and bone alkaline phosphatase [BALP]) were measured at baseline and at 1, 6, 12, 24, and 36 months. Decreases in CTX were more rapid and greater than decreases in PINP and BALP. One month after injection, CTX levels in all denosumab-treated subjects decreased to levels below the premenopausal reference interval. CTX values at the end of the dosing period were influenced by baseline CTX values and the dosing interval. The percentage of subjects with CTX below the premenopausal reference interval before each subsequent injection decreased from 79% to 51% during the study. CTX and PINP remained below the premenopausal reference interval at all time points in 46% and 31% denosumab-treated subjects, respectively. With denosumab, but not placebo, there were significant correlations between CTX reduction and BMD increase (r = -0.24 to -0.44). The BTM response pattern with denosumab is unique and should be appreciated by physicians to monitor this treatment effectively.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Remodelação Óssea/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/fisiopatologia , Ligante RANK/farmacologia , Ligante RANK/uso terapêutico , Fosfatase Ácida/sangue , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Anticorpos Monoclonais Humanizados , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Colágeno Tipo I/sangue , Denosumab , Relação Dose-Resposta a Droga , Feminino , Humanos , Isoenzimas/sangue , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/enzimologia , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Valores de Referência , Estatísticas não Paramétricas , Fosfatase Ácida Resistente a Tartarato
9.
J Natl Cancer Inst ; 102(22): 1706-15, 2010 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-21051656

RESUMO

BACKGROUND: Currently available selective estrogen receptor modulators reduce the risk of breast cancer, but they are not widely used. In the Postmenopausal Evaluation and Risk-Reduction with Lasofoxifene (PEARL) trial, lasofoxifene was shown to reduce the risk of estrogen receptor-positive (ER+) breast cancer, nonvertebral and vertebral fractures, coronary artery disease, and stroke, but the effects on total breast cancer (invasive and ductal carcinoma in situ, ER+ and estrogen receptor-negative [ER-]) and ER+ invasive breast cancer are unknown. METHODS: Postmenopausal women (n = 8556) aged 59-80 years with low bone density and normal mammograms were randomly assigned to two doses of lasofoxifene (0.25 and 0.5 mg) or placebo. The primary endpoints of the PEARL trial were incidence of ER+ breast cancer and nonvertebral fractures at 5 years. A nested case-control study of 49 incident breast cancer case patients and 156 unaffected control subjects from the PEARL trial was performed to evaluate treatment effects on risk of total and ER+ invasive breast cancer by baseline serum estradiol and sex hormone-binding globulin levels using logistic regression models. Cox proportional hazards models were used to evaluate risk of total breast cancer and ER+ invasive breast cancer using intention-to-treat analysis. All statistical tests were two-sided. RESULTS: Breast cancer was confirmed in 49 women. Compared with placebo, 0.5 mg of lasofoxifene statistically significantly reduced the risk of total breast cancer by 79% (hazard ratio = 0.21; 95% confidence interval [CI] = 0.08 to 0.55) and ER+ invasive breast cancer by 83% (hazard ratio = 0.17; 95% CI = 0.05 to 0.57). The effects of 0.5 mg of lasofoxifene on total breast cancer were similar regardless of Gail score, whereas the effects were markedly stronger for women with baseline estradiol levels greater than the median (odds ratio = 0.11; 95% CI = 0.02 to 0.51) vs those with levels less than the median (odds ratio = 0.78; 95% CI = 0.16 to 3.79; P(interaction) = .04). CONCLUSION: A 0.5-mg dose of lasofoxifene appears to reduce the risks of both total and ER+ invasive breast cancer in postmenopausal women with osteoporosis.


Assuntos
Anticarcinógenos/uso terapêutico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/prevenção & controle , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Ductal de Mama/prevenção & controle , Estradiol/sangue , Fraturas Ósseas/prevenção & controle , Osteoporose Pós-Menopausa/prevenção & controle , Pirrolidinas/uso terapêutico , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Tetra-Hidronaftalenos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/uso terapêutico , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Estudos de Casos e Controles , Método Duplo-Cego , Feminino , Fraturas Ósseas/complicações , Fraturas Ósseas/etiologia , Humanos , Incidência , Mamografia , Pessoa de Meia-Idade , Razão de Chances , Osteoporose Pós-Menopausa/complicações , Prevenção Primária/métodos , Receptores de Estrogênio/sangue , Medição de Risco , Globulina de Ligação a Hormônio Sexual/metabolismo , Resultado do Tratamento , Estados Unidos/epidemiologia
10.
BMC Geriatr ; 10: 55, 2010 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-20716351

RESUMO

BACKGROUND: Prediction of long-term survival in healthy adults requires recognition of features that serve as early indicators of successful aging. The aims of this study were to identify predictors of long-term survival in older women and to develop a multivariable model based upon longitudinal data from the Study of Osteoporotic Fractures (SOF). METHODS: We considered only the youngest subjects (n = 4,097) enrolled in the SOF cohort (65 to 69 years of age) and excluded older SOF subjects more likely to exhibit a "frail" phenotype. A total of 377 phenotypic measures were screened to determine which were of most value for prediction of long-term (19-year) survival. Prognostic capacity of individual predictors, and combinations of predictors, was evaluated using a cross-validation criterion with prediction accuracy assessed according to time-specific AUC statistics. RESULTS: Visual contrast sensitivity score was among the top 5 individual predictors relative to all 377 variables evaluated (mean AUC = 0.570). A 13-variable model with strong predictive performance was generated using a forward search strategy (mean AUC = 0.673). Variables within this model included a measure of physical function, smoking and diabetes status, self-reported health, contrast sensitivity, and functional status indices reflecting cumulative number of daily living impairments (HR >or= 0.879 or RH

Assuntos
Envelhecimento/fisiologia , Mineração de Dados/métodos , Nível de Saúde , Sobreviventes , Idoso , Estudos de Coortes , Mineração de Dados/tendências , Feminino , Humanos , Estudos Longitudinais , Osteoporose/mortalidade , Valor Preditivo dos Testes , Estudos Prospectivos , Taxa de Sobrevida/tendências
11.
J Clin Oncol ; 28(24): 3830-7, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20644098

RESUMO

PURPOSE: We determined whether the association between breast density and breast cancer risk and cancer severity differs according to menopausal status and postmenopausal hormone therapy (HT) use. METHODS: We collected data on 587,369 women who underwent 1,349,027 screening mammography examinations; 14,090 women were diagnosed with breast cancer. We calculated 5-year breast cancer risk from a survival model for subgroups of women classified by their Breast Imaging Reporting and Data System (BIRADS) breast density, age, menopausal status, and current HT use, assuming a body mass index of 25 kg/m(2). Odds of advanced (ie, IIb, III, IV) versus early (ie, I, IIa) stage invasive cancer was calculated according to BIRADS density. RESULTS: Breast cancer risk was low among women with low density (BIRADS-1): women age 55 to 59 years, 5-year risk was 0.8% (95% CI, 0.6 to 0.9%) for non-HT users and 0.9% (95% CI, 0.7% to 1.1%) for estrogen and estrogen plus progestin users. Breast cancer risk was high among women with very high density (BIRADS-4), particularly estrogen plus progestin users: women age 55 to 59 years, 5-year risk was 2.4% (95% CI, 2.0% to 2.8%) for non-HT users, 3.0% (95% CI, 2.6% to 3.5%) for estrogen users, and 4.2% (95% CI, 3.7% to 4.6%) for estrogen plus progestin users. Advanced-stage breast cancer risk was increased 1.7-fold for postmenopausal HT users who had very high density (BIRADS-4) compared to those with average density (BIRADS-2). CONCLUSION: Postmenopausal women with high breast density are at increased risk of breast cancer and should be aware of the added risk of taking HT, especially estrogen plus progestin.


Assuntos
Neoplasias da Mama/induzido quimicamente , Mama/patologia , Terapia de Reposição de Estrogênios/efeitos adversos , Mamografia , Programas de Rastreamento , Pós-Menopausa , Fatores Etários , Idoso , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Estrogênios/administração & dosagem , Estrogênios/efeitos adversos , Feminino , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Progestinas/administração & dosagem , Progestinas/efeitos adversos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença
12.
Am J Epidemiol ; 171(8): 909-16, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20237150

RESUMO

A higher serum phosphorus level is associated with cardiovascular disease (CVD) events among community-living populations. Mechanisms are unknown. The ankle-brachial index (ABI) provides information on both atherosclerosis and arterial stiffness. In this cross-sectional study (2000-2002), the authors evaluated the association of serum phosphorus levels with low (<0.90) and high (> or =1.40 or incompressible) ABI as compared with intermediate ABI in 5,330 older US men, among whom the mean serum phosphorus level was 3.2 mg/dL (standard deviation, 0.4), 6% had a low ABI, and 5% had a high ABI. Each 1-mg/dL increase in serum phosphorus level was associated with a 1.6-fold greater prevalence of low ABI (95% confidence interval (CI): 1.2, 2.1; P < 0.001) and a 1.4-fold greater prevalence of high ABI (95% CI: 1.0, 1.9; P = 0.03) in models adjusted for demographic factors, traditional CVD risk factors, and kidney function. However, the association of phosphorus with high ABI differed by chronic kidney disease (CKD) status (in persons with CKD, prevalence ratio = 2.96, 95% CI: 1.61, 5.45; in persons without CKD, prevalence ratio = 1.14, 95% CI: 0.81, 1.61; interaction P = 0.04). In conclusion, among community-living older men, higher phosphorus levels are associated with low ABI and are also associated with high ABI in persons with CKD. These associations may explain the link between serum phosphorus levels and CVD events.


Assuntos
Índice Tornozelo-Braço , Hiperfosfatemia , Hipofosfatemia , Homens , Doenças Vasculares Periféricas/epidemiologia , Fósforo/sangue , Idoso , Análise de Variância , Distribuição de Qui-Quadrado , Estudos Transversais , Fraturas Ósseas/complicações , Fraturas Ósseas/epidemiologia , Humanos , Hiperfosfatemia/sangue , Hiperfosfatemia/complicações , Hiperfosfatemia/epidemiologia , Hipofosfatemia/sangue , Hipofosfatemia/complicações , Hipofosfatemia/epidemiologia , Falência Renal Crônica/complicações , Falência Renal Crônica/epidemiologia , Modelos Logísticos , Masculino , Osteoporose/complicações , Osteoporose/epidemiologia , Doenças Vasculares Periféricas/complicações , Doenças Vasculares Periféricas/diagnóstico , Prevalência , Fatores de Risco , Estatísticas não Paramétricas , Inquéritos e Questionários , Estados Unidos/epidemiologia
13.
Am J Clin Nutr ; 90(5): 1336-42, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19740971

RESUMO

BACKGROUND: Change in body composition, specifically loss of fat-free mass and gain in fat mass, in older adults is a major pathway leading to the onset of functional decline and physical disability. OBJECTIVE: The objective was to determine the association of activity-related energy expenditure with change in body mass and composition among older men and women. DESIGN: Total energy expenditure (TEE) was assessed over 2 wk by using the doubly labeled water method in 302 community-dwelling older adults aged 70-82 y. Resting metabolic rate (RMR) was measured by using indirect calorimetry, and the thermic effect of meals was estimated at 10% of TEE. Activity energy expenditure (AEE) was calculated as [TEE(0.9) - RMR]. Total body mass, fat-free mass (FFM), and fat mass (FM) were assessed by dual-energy X-ray absorptiometry annually over a mean (+/-SD) of 4.9 +/- 1.3 y. RESULTS: In multivariate models adjusted for baseline age, smoking status, and race, men and women had a decline (in kg/y) in body mass (men: -0.34, 95% CI: -0.71, 0.02; women: -0.45, 95% CI: -0.71, -0.19) and FFM (men: -0.48, 95% CI: -0.67, -0.29; women: -0.14, 95% CI: -0.026, -0.03). No changes (in kg/y) were observed in FM (men: 0.14, 95% CI: -0.10, 0.38; women: -0.28, 95% CI: -0.49, -0.07). In men and women, higher AEE at baseline was associated with greater FFM. The average change in these outcomes (ie, slope), however, was similar across tertiles of AEE. CONCLUSIONS: These data suggest that accumulated energy expenditure from all physical activities is associated with greater FFM, but the effect does not alter the trajectory of FFM change in late life.


Assuntos
Envelhecimento/fisiologia , Metabolismo Basal/fisiologia , Composição Corporal , Metabolismo Energético , Tecido Adiposo/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Pessoas com Deficiência/estatística & dados numéricos , Feminino , Humanos , Masculino , Descanso/fisiologia , Fumar/epidemiologia
14.
Diabetes Metab Res Rev ; 25(8): 733-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19780064

RESUMO

BACKGROUND: Accumulating evidence suggests a cross-sectional association between oxidative stress and type 2 diabetes (T2D). Systemic oxidative stress, as measured by oxidized LDL (oxLDL), has been correlated with visceral fat. We examined the relationship between oxLDL, and T2D- and obesity-related traits in a bi-racial sample of 2985 subjects at baseline and after 7 years of follow-up. METHODS: We examined six T2D-related traits (T2D status, HbA(1c), fasting glucose, insulin, adiponectin and HOMA-IR) as well as six obesity-related traits (obesity status, BMI, leptin, % body fat, visceral and subcutaneous fat mass) using logistic and linear regression models. RESULTS: In all subjects at baseline, oxLDL was positively associated with T2D (OR = 1.3, 95% CI:1.1-1.5), fasting glucose (ss = 0.03 +/- 0.006), HbA(1c) (ss = 0.02 +/- 0.004), fasting insulin (ss = 0.12 +/- 0.02), HOMA-IR (ss = 0.13 +/- 0.02) and negatively with adiponectin (ss = -0.16 +/- 0.03), (all p < 0.001). The strength and magnitude of these associations did not differ much between blacks and whites. In both blacks and whites, oxLDL was also associated with obesity (OR = 1.3, 95% CI:1.1-1.4) and three of its related traits (ss = 0.60 +/- 0.14 for BMI, ss = 0.74 +/- 0.17 for % body fat, ss = 0.29 +/- 0.06 for visceral fat; all p < 0.001). Furthermore, of four traits measured after 7 years of follow-up (fasting glucose, HbA1c, BMI and % fat), their relationship with oxLDL was similar to baseline observations. No significant association was found between oxLDL and incident T2D. Interestingly, oxLDL was significantly associated with % change in T2D- and obesity-related traits in whites but not in blacks. CONCLUSION/INTERPRETATION: Our data suggest that systemic oxidative stress may be a novel risk factor for T2D and obesity.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Lipoproteínas LDL/sangue , Obesidade/complicações , Adiponectina/sangue , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Glicemia/análise , Composição Corporal , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Hemoglobinas Glicadas/análise , Humanos , Insulina/sangue , Resistência à Insulina , Leptina/sangue , Masculino , Obesidade/sangue , Obesidade/fisiopatologia , Oxirredução , Valor Preditivo dos Testes , Estudos Prospectivos , Estatística como Assunto , Inquéritos e Questionários , Estados Unidos , População Branca/estatística & dados numéricos
15.
J Gerontol A Biol Sci Med Sci ; 64(8): 860-4, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19435951

RESUMO

Although telomere length (TL) is known to play a critical role in cellular senescence, the relationship of TL to aging and longevity in humans is not well understood. In a large biracial population-based cohort, we tested the hypotheses that elderly persons with shorter TL in peripheral white blood cells have poorer survival, shorter life span, and fewer years of healthy life (YHL). Associations were evaluated using Cox proportional hazard models and linear regression analyses where appropriate. TL (in kilo base pairs) was not associated with overall survival (hazard ratio 1.0; 95% confidence interval 0.9-1.1) or death from any specific underlying cause including infectious diseases, cancer, or cardiac and cerebrovascular diseases. TL, however, was positively associated with more YHL (beta = 0.08 +/- 0.04, p = .03). Findings suggest that TL may not be a strong biomarker of survival in older individuals, but it may be an informative biomarker of healthy aging.


Assuntos
Envelhecimento , Composição Corporal , Causas de Morte , Nível de Saúde , Telômero , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino
16.
Exp Gerontol ; 44(5): 350-5, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19249341

RESUMO

Interleukin-6 (IL-6) is an inflammatory cytokine that influences the development of inflammatory and aging-related disorders and ultimately longevity. In order to study the influence of variants in genes that regulate inflammatory response on IL-6 levels and longevity, we screened a panel of 477 tag SNPs across 87 candidate genes in >5000 older participants from the population-based Cardiovascular Health Study (CHS). Baseline plasma IL-6 concentration was first confirmed as a strong predictor of all-cause mortality. Functional alleles of the IL6R and PARP1 genes were significantly associated with 15%-20% higher baseline IL-6 concentration per copy among CHS European-American (EA) participants (all p<10(-4)). In a case/control analysis nested within this EA cohort, the minor allele of PARP1 rs1805415 was nominally associated with decreased longevity (p=0.001), but there was no evidence of association between IL6R genotype and longevity. The PARP1 rs1805415--longevity association was subsequently replicated in one of two independent case/control studies. In a pooled analysis of all three studies, the "risk" of longevity associated with the minor allele of PARP1 rs1805415 was 0.79 (95%CI 0.62-1.02; p=0.07). These findings warrant further study of the potential role of PARP1 genotype in inflammatory and aging-related phenotypes.


Assuntos
Doenças Cardiovasculares/sangue , Inflamação/sangue , Interleucina-6/sangue , Poli(ADP-Ribose) Polimerases/sangue , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/mortalidade , Estudos de Casos e Controles , Feminino , Variação Genética , Genótipo , Humanos , Inflamação/genética , Inflamação/mortalidade , Interleucina-6/genética , Longevidade/genética , Masculino , Fenótipo , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética , Fatores de Risco
17.
Clin Trials ; 5(1): 56-60, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18283081

RESUMO

PURPOSE: The use of centralized systems to adjudicate clinical events is common in large clinical trials, in spite of relatively little published literature concerning the rationale and justification. The purpose of this manuscript is to review the reasons for central adjudication and to discuss whether trials could be simplified by limiting or streamlining the adjudication process. METHODS: We reviewed the literature concerning central adjudication and documented the experience of adjudication in several clinical trials. Since definitions for nonfatal events are generally heterogeneous and subjective, one reason for a central process of adjudication is to assist in assuring systematic application of the definition used in the trial. In open-label trials, assuring that the adjudication is done blinded to treatment assignment may provide protection against differential misclassification. Regulatory authorities, including the FDA, derive confidence in the validity of results when central adjudication is performed. The clinical community has become accustomed to a certain amount of adjudication and may criticize trials that lack adjudication. LIMITATIONS: It is difficult to document the value of adjudication in trials that have reported adjudicated and nonadjudicated event rates and related treatment effects. Making rationale decisions about when and how to adjudicate is hampered by the lack of published study of when and how central adjudication is helpful to improve the quality and validity of trials and at what cost. CONCLUSIONS: Adjudication has not been shown to improve the ability to determine treatment effects. Thus, adjudication may be overly complex and overused in many large simple trials. The appropriate role of central adjudication - which trials, which outcomes, what methods - deserves scrutiny and further study.


Assuntos
Ensaios Clínicos como Assunto/métodos , Tomada de Decisões , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Projetos de Pesquisa , Resultado do Tratamento
18.
Hum Genet ; 121(5): 615-24, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17390149

RESUMO

Adipocytokines are a subset of cytokines produced by adipose tissue and are associated with risk of type II diabetes and atherosclerosis. Levels of adipocytokines differ between Black and White Americans, even after adjustment for differences in adiposity, diseases associated with adipocytokines including type 2 diabetes and cardiovascular disease, and general socioeconomic status indicators such as income. We used a series of ancestry informative markers to estimate genetic ancestry in a population-based study of older Black Americans, and examined the association between genetic ancestry and adipocytokines and soluble receptors to help determine which of these may be most amenable to admixture mapping. We typed 35 ancestry informative markers in 1,241 self-reported Black Americans with available DNA from the Health, Aging, and Body Composition (Health ABC) study with available DNA and used a maximum likelihood approach to estimate percent European ancestry. We used linear regression models to determine the association between these adipocytokines and percent ancestry, and staged models to examine whether adiposity or other measures affected the associations of genetic ancestry and adipocytokines. Mean European ancestry was 22.3+/-15.9%. In multivariate adjusted models, the strongest associations observed were between higher European ancestry and interleukin-6 soluble receptor (IL-6 SR), C-reactive protein (CRP), and adiponectin levels, with interleukin-2 soluble receptor (IL-2 SR) and soluble tumor necrosis factor receptor II (TNF-alpha SR II) also showing more modest but significant associations. The association with adiponectin became stronger after adjustment for adiposity. These novel findings suggest that admixture mapping may identify genetic factors influencing the levels of IL-6 SR, CRP, IL-2 SR, and adiponectin.


Assuntos
Envelhecimento/genética , Negro ou Afro-Americano/genética , Composição Corporal/genética , Tecido Adiposo/metabolismo , Idoso , Citocinas/genética , Feminino , Marcadores Genéticos , Humanos , Funções Verossimilhança , Masculino
19.
J Bone Miner Res ; 22(2): 184-94, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17228995

RESUMO

UNLABELLED: Few genome-wide linkage studies of osteoporosis have been conducted in the Asian population. We performed a genome-wide scan involving 3093 adult siblings with at least one sib-pair extremely concordant or discordant for hip BMD. Our results indicated four genome-wide significant QTLs for BMD. In comparison with 12 previous reported linkage studies, we reveal novel linkage regions that have reaching global significance. INTRODUCTION: The genetic basis for osteoporosis has been firmly established, but efforts to identify genes associated with this complex trait have been incomplete, especially in Asian populations. The purpose of this study was to identify quantitative trait loci (QTLs) for BMD in a Chinese population. MATERIALS AND METHODS: We performed a genome-wide scan involving 3093 siblings 25-64 years of age from 941 families, with at least one sib-pair extreme concordant or discordant for total hip BMD from a large community-based cohort (n = 23,327) in Anhui, China. Linkage analysis was performed on BMD residuals adjusted for age, height, weight, occupation, cigarette smoking, physical activity, and alcohol consumption using the revised Haseman-Elston regression-based linkage model. RESULTS: Our results revealed significant QTLs on chromosome 7p21.2 for femoral neck BMD (LOD = 3.68) and on chromosome 2q24.3 for total hip BMD (LOD = 3.65). Suggestive linkage regions were found to overlap among different skeletal sites on chromosomes 2q, 7p, and 16q. Sex-specific linkage analysis further revealed a significant QTL for lumbar spine BMD on chromosome 13q21.1 (LOD = 3.62) in women only. When performing multivariate linkage analysis by combining BMDs at four skeletal sites (i.e., whole body, total hip, femoral neck, and lumbar spine BMD), an additional significant QTL was found at chromosome 5q21.2 (LOD = 4.56). None of these significant QTLs found in our study overlapped with major QTLs reported by other studies. CONCLUSIONS: This study reveals four novel QTLs in a Chinese population and suggests that BMD at different skeletal sites may also share common genetic determinants.


Assuntos
Densidade Óssea/genética , Ligação Genética , Genoma Humano , Irmãos , Povo Asiático , Mapeamento Cromossômico , Feminino , Humanos , Masculino , Locos de Características Quantitativas , Fatores Sexuais
20.
Arch Intern Med ; 167(2): 155-60, 2007 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-17242316

RESUMO

BACKGROUND: Whether repeat bone mineral density (BMD) measurement adds benefit beyond the initial BMD measurement in predicting fractures in older women is unknown. METHODS: We prospectively measured total hip BMD in 4124 older women (mean +/- SD age, 72 +/- 4 years) from 1989 to 1990 and again 8 years later. Incident nontraumatic hip and nonspine fractures were validated by radiology reports (>95% follow-up). In addition, spine fractures were defined morphometrically in 2129 of these women by lateral spine x-ray films from 1991 to 1992 and then again 11.4 years later. Prediction of fracture risk was assessed with proportional hazards models and receiver operating characteristic curves for BMD measures. RESULTS: Over a mean of 5 years after the repeat BMD measure, 877 women experienced an incident nontraumatic nonspine fracture (275 hip fractures). In addition, 340 women developed a spine fracture. After adjustment for age and weight change, initial and repeat BMD measurements were similarly associated with fracture risk (per unit standard deviation lower in BMD) for nonspine (hazard ratio, 1.6), spine (odds ratio, 1.8-1.9), and hip (hazard ratio, 2.0-2.2) fractures (P<.001 for all models). Areas under the receiver operating characteristic curves (AUC) revealed no significant differences to discriminate nonspine (AUC, 0.65), spine (AUC, 0.67-0.68), or hip (AUC, 0.73-0.74) fractures between models with initial BMD, repeat BMD, or initial BMD plus change in BMD. Stratification by initial BMD t scores (normal, osteopenic, or osteoporotic), high bone loss, or hormone therapy did not alter results. CONCLUSION: In healthy, older, postmenopausal women, repeating a measurement of BMD up to 8 years later provides little additional value besides the initial BMD measurement for predicting incident fractures.


Assuntos
Densidade Óssea , Fraturas Ósseas/epidemiologia , Idoso , Área Sob a Curva , Feminino , Fraturas Ósseas/fisiopatologia , Humanos , Modelos Logísticos , Estudos Prospectivos , Curva ROC , Radiografia , Medição de Risco , Coluna Vertebral/diagnóstico por imagem
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