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1.
PLoS One ; 19(4): e0298952, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635767

RESUMO

BACKGROUND: Our understanding of the specific aspects of vascular contributions to dementia remains unclear. OBJECTIVES: We aim to identify the correlates of incident dementia in a multi-ethnic cardiovascular cohort. METHODS: A total of 6806 participants with follow-up data for incident dementia were included. Probable dementia diagnoses were identified using hospitalization discharge diagnoses according to the International Classification of Diseases Codes (ICD). We used Random Forest analyses to identify the correlates of incident dementia and cognitive function from among 198 variables collected at the baseline MESA exam entailing demographic risk factors, medical history, anthropometry, lab biomarkers, electrocardiograms, cardiovascular magnetic resonance imaging, carotid ultrasonography, coronary artery calcium and liver fat content. Death and stroke were considered competing events. RESULTS: Over 14 years of follow-up, 326 dementia events were identified. Beyond age, the top correlates of dementia included coronary artery calcification, high sensitivity troponin, common carotid artery intima to media thickness, NT-proBNP, physical activity, pulse pressure, tumor necrosis factor-α, history of cancer, and liver to spleen attenuation ratio from computed tomography. Correlates of cognitive function included income and physical activity, body size, serum glucose, glomerular filtration rate, measures of carotid artery stiffness, alcohol use, and inflammation indexed as IL-2 and TNF soluble receptors and plasmin-antiplasmin complex. CONCLUSION: In a deeply phenotyped cardiovascular cohort we identified the key correlates of dementia beyond age as subclinical atherosclerosis and myocyte damage, vascular function, inflammation, physical activity, hepatic steatosis, and history of cancer.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Doença da Artéria Coronariana , Demência , Neoplasias , Humanos , Fatores de Risco , Espessura Intima-Media Carotídea , Inflamação , Demência/diagnóstico , Incidência
2.
Ann Appl Stat ; 17(2): 1375-1397, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37284167

RESUMO

With the availability of massive amounts of data from electronic health records and registry databases, incorporating time-varying patient information to improve risk prediction has attracted great attention. To exploit the growing amount of predictor information over time, we develop a unified framework for landmark prediction using survival tree ensembles, where an updated prediction can be performed when new information becomes available. Compared to conventional landmark prediction with fixed landmark times, our methods allow the landmark times to be subject-specific and triggered by an intermediate clinical event. Moreover, the nonparametric approach circumvents the thorny issue of model incompatibility at different landmark times. In our framework, both the longitudinal predictors and the event time outcome are subject to right censoring, and thus existing tree-based approaches cannot be directly applied. To tackle the analytical challenges, we propose a risk-set-based ensemble procedure by averaging martingale estimating equations from individual trees. Extensive simulation studies are conducted to evaluate the performance of our methods. The methods are applied to the Cystic Fibrosis Foundation Patient Registry (CFFPR) data to perform dynamic prediction of lung disease in cystic fibrosis patients and to identify important prognosis factors.

3.
Blood ; 142(3): 244-259, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37084382

RESUMO

Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome is caused by somatic mutations in UBA1 (UBA1mut) and characterized by heterogenous systemic autoinflammation and progressive hematologic manifestations, meeting criteria for myelodysplastic syndrome (MDS) and plasma cell dyscrasias. The landscape of myeloid-related gene mutations leading to typical clonal hematopoiesis (CH) in these patients is unknown. Retrospectively, we screened 80 patients with VEXAS for CH in their peripheral blood (PB) and correlated the findings with clinical outcomes in 77 of them. UBA1mut were most common at hot spot p.M41 (median variant allele frequency [VAF] = 75%). Typical CH mutations cooccurred with UBA1mut in 60% of patients, mostly in DNMT3A and TET2, and were not associated with inflammatory or hematologic manifestations. In prospective single-cell proteogenomic sequencing (scDNA), UBA1mut was the dominant clone, present mostly in branched clonal trajectories. Based on integrated bulk and scDNA analyses, clonality in VEXAS followed 2 major patterns: with either typical CH preceding UBA1mut selection in a clone (pattern 1) or occurring as an UBA1mut subclone or in independent clones (pattern 2). VAF in the PB differed markedly between DNMT3A and TET2 clones (median VAF of 25% vs 1%). DNMT3A and TET2 clones associated with hierarchies representing patterns 1 and 2, respectively. Overall survival for all patients was 60% at 10 years. Transfusion-dependent anemia, moderate thrombocytopenia, and typical CH mutations, each correlated with poor outcome. In VEXAS, UBA1mut cells are the primary cause of systemic inflammation and marrow failure, being a new molecularly defined somatic entity associated with MDS. VEXAS-associated MDS is distinct from classical MDS in its presentation and clinical course.


Assuntos
Hematopoiese Clonal , Dermatite , Humanos , Hematopoiese Clonal/genética , Estudos Prospectivos , Estudos Retrospectivos , Mutação
4.
Am J Hematol ; 98(6): 932-939, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37021397

RESUMO

Immune severe aplastic anemia (SAA) is characterized by pancytopenia and immune-mediated bone marrow destruction. SAA may be treated with hematopoietic stem cell transplantation (HSCT) or immunosuppressive therapy (IST). However, 30% of patients treated with IST relapse. We previously reported a clinical trial of alemtuzumab in which more than half of 25 relapsed SAA patients (56%) responded hematologically. Here, we present long-term results of a total of 42 patients. Participants with SAA who had previously completed antithymocyte globulin (ATG)-based IST, but had relapsed, were enrolled on this study. Alemtuzumab was administered intravenously (IV) (n = 28) or subcutaneously (SC) (n = 14). The primary endpoint was hematologic response at 6 months. Secondary endpoints included relapse, clonal evolution, and survival. This trial was registered at clinicaltrials.gov (NCT00195624). Patients were enrolled over 9 years, with median follow-up of 6 years. Median age was 32 years, with 57% being female. At 6 months, 18 patients (43%) achieved response; 15 (54%) of those who received IV compared with 3 (21%) who received SC therapy. Six patients (14%) had durable long-term response without need for subsequent AA-directed therapy or HSCT at last follow-up. Nine patients had clonal evolution, with high-risk evolution occurring in 6. Overall survival was 67% at median follow-up of 6 years. Prolonged iatrogenic immunosuppression was observed as long as 2 years after alemtuzumab administration. Alemtuzumab induces responses in relapsed SAA, some of which are durable long-term. However, immunosuppression can persist for years, requiring long-term monitoring.


Assuntos
Anemia Aplástica , Imunossupressores , Humanos , Feminino , Adulto , Masculino , Imunossupressores/efeitos adversos , Ciclosporina/uso terapêutico , Alemtuzumab/uso terapêutico , Anemia Aplástica/tratamento farmacológico , Resultado do Tratamento , Soro Antilinfocitário/uso terapêutico , Recidiva
5.
Blood ; 141(17): 2100-2113, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36542832

RESUMO

The choice to postpone treatment while awaiting genetic testing can result in significant delay in definitive therapies in patients with severe pancytopenia. Conversely, the misdiagnosis of inherited bone marrow failure (BMF) can expose patients to ineffectual and expensive therapies, toxic transplant conditioning regimens, and inappropriate use of an affected family member as a stem cell donor. To predict the likelihood of patients having acquired or inherited BMF, we developed a 2-step data-driven machine-learning model using 25 clinical and laboratory variables typically recorded at the initial clinical encounter. For model development, patients were labeled as having acquired or inherited BMF depending on their genomic data. Data sets were unbiasedly clustered, and an ensemble model was trained with cases from the largest cluster of a training cohort (n = 359) and validated with an independent cohort (n = 127). Cluster A, the largest group, was mostly immune or inherited aplastic anemia, whereas cluster B comprised underrepresented BMF phenotypes and was not included in the next step of data modeling because of a small sample size. The ensemble cluster A-specific model was accurate (89%) to predict BMF etiology, correctly predicting inherited and likely immune BMF in 79% and 92% of cases, respectively. Our model represents a practical guide for BMF diagnosis and highlights the importance of clinical and laboratory variables in the initial evaluation, particularly telomere length. Our tool can be potentially used by general hematologists and health care providers not specialized in BMF, and in under-resourced centers, to prioritize patients for genetic testing or for expeditious treatment.


Assuntos
Anemia Aplástica , Doenças da Medula Óssea , Pancitopenia , Humanos , Doenças da Medula Óssea/diagnóstico , Doenças da Medula Óssea/genética , Doenças da Medula Óssea/terapia , Diagnóstico Diferencial , Anemia Aplástica/diagnóstico , Anemia Aplástica/genética , Anemia Aplástica/terapia , Transtornos da Insuficiência da Medula Óssea/diagnóstico , Pancitopenia/diagnóstico
6.
Leukemia ; 36(9): 2328-2337, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35896822

RESUMO

Predictors, genetic characteristics, and long-term outcomes of patients with SAA who clonally evolved after immunosuppressive therapy (IST) were assessed. SAA patients were treated with IST from 1989-2020. Clonal evolution was categorized as "high-risk" (overt myeloid neoplasm [meeting WHO criteria for dysplasia, MPN or acute leukemia] or isolated chromosome-7 abnormality/complex karyotype without dysplasia or overt myeloid neoplasia) or "low-risk" (non-7 or non-complex chromosome abnormalities without morphological evidence of dysplasia or myeloid neoplasia). Univariate and multivariate analysis using Fine-Gray competing risk regression model determined predictors. Long-term outcomes included relapse, overall survival (OS) and hematopoietic stem cell transplant (HSCT). Somatic mutations in myeloid cancer genes were assessed in evolvers and in 407 patients 6 months after IST. Of 663 SAA patients, 95 developed clonal evolution. Pre-treatment age >48 years and ANC > 0.87 × 109/L were strong predictors of high-risk evolution. OS was 37% in high-risk clonal evolution by 5 years compared to 94% in low-risk. High-risk patients who underwent HSCT had improved OS. Eltrombopag did not increase high-risk evolution. Splicing factors and RUNX1 somatic variants were detected exclusively at high-risk evolution; DNMT3A, BCOR/L1 and ASXL1 were present in both. RUNX1, splicing factors and ASXL1 somatic mutations detected at 6 months after IST predicted high-risk evolution.


Assuntos
Anemia Aplástica , Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Evolução Clonal , Subunidade alfa 2 de Fator de Ligação ao Core , Humanos , Terapia de Imunossupressão , Imunossupressores , Pessoa de Meia-Idade , Fatores de Processamento de RNA
8.
Blood ; 139(1): 34-43, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34525188

RESUMO

Patients with severe aplastic anemia (SAA) are either treated with bone marrow transplant (BMT) or immunosuppression (IST) depending on their age, comorbidities, and available donors. In 2017, our phase 2 trial reported improved hematologic responses with the addition of eltrombopag (EPAG) to standard IST for SAA when compared with a historical cohort treated with IST alone. However, the rates and characteristics of long-term complications, relapse, and clonal evolution, previously described in patients treated with IST alone, are not yet known with this new regimen, IST and EPAG. Patients were accrued from 2012 to 2020, with a total of 178 subjects included in this secondary endpoint analysis. With double the sample size and a much longer median follow-up (4 years) since the original publication in 2017, we report a cumulative relapse rate of 39% in responding patients who received cyclosporine (CSA) maintenance and clonal evolution of 15% in all treated patients at 4 years. Relapse occurred at distinct timepoints: after CSA dose reduction and EPAG discontinuation at 6 months, and after 2 years when CSA was discontinued. Most relapsed patients were retreated with therapeutic doses of CSA +/- EPAG, and two-thirds responded. Clonal evolution to a myeloid malignancy or chromosome 7 abnormality (high-risk) was noted in 5.7% of patients and conferred a poorer overall survival. Neither relapse nor high-risk evolution occurred at a higher rate than was observed in a historical comparator cohort, but the median time to both events was earlier in IST and EPAG treated patients. This trial was registered at www.clinicaltrials.gov as #NCT01623167.


Assuntos
Anemia Aplástica/tratamento farmacológico , Benzoatos/uso terapêutico , Ciclosporina/uso terapêutico , Hidrazinas/uso terapêutico , Imunossupressores/uso terapêutico , Pirazóis/uso terapêutico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
9.
Front Endocrinol (Lausanne) ; 12: 785957, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34966360

RESUMO

Aims: Anecdotal reports have suggested increased soft tissue calcification in individuals with long-term exposures to high blood glucose. The association of costal cartilage calcification (CCC), a reliably quantifiable marker obtainable from non-contrast cardiac computed tomography (CT) with cumulative fasting blood glucose (FBG) exposure, is unknown. In this study, we aimed to determine the association between quantified CCC and cumulative glucose exposure using non-contrast coronary artery calcium (CAC) scoring computed tomography (CT) images in the Multi-Ethnic Study of Atherosclerosis (MESA). Methods: The volume of bilateral CCC was quantified in high-density pixels (threshold of Hounsfield Unit>180) using the CAC scoring CT images acquired in the 5th MESA exam. Prior long-term cumulative exposure to FBG was calculated by area under the FBG-time curve over ten years before the time of the CT exam. Results: A total of 2,305 participants (mean age: 69, female/male: 1.3) were included in this study. The median CCC volume was lower in females than males (1158 mm3 [IQR: 1751] vs. 3054 mm3 [3851], p<0.001). In cross-sectional analysis, quantified CCC was associated with FBG (9% increase per SD) and HbA1c (7% increase per SD) at the CT exam only in female participants after adjustment for age, race, BMI, and glomerular filtration rate. Only in female participants, quantified CCC was also associated with prior cumulative FBG (3% increase per decile change). In the subgroup of females with zero CAC scores, the adjusted CCC was still associated with FBG (13% increase per SD) at the time of CT exam and with prior cumulative FBG exposure (4% increase per decile change) before the CT exam. Conclusions: The CCC, a reliably quantified marker in non-contrast cardiac CT, is associated with 10-year cumulative FBG exposure only in female participants, even those with zero CAC.


Assuntos
Aterosclerose/diagnóstico por imagem , Aterosclerose/etnologia , Glicemia/metabolismo , Calcinose/diagnóstico por imagem , Calcinose/etnologia , Cartilagem Costal/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/sangue , Calcinose/sangue , Estudos de Coortes , Cartilagem Costal/metabolismo , Estudos Transversais , Etnicidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
10.
Blood ; 138(26): 2799-2809, 2021 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-34724566

RESUMO

Immune aplastic anemia (AA) features somatic loss of HLA class I allele expression on bone marrow cells, consistent with a mechanism of escape from T-cell-mediated destruction of hematopoietic stem and progenitor cells. The clinical significance of HLA abnormalities has not been well characterized. We examined the somatic loss of HLA class I alleles and correlated HLA loss and mutation-associated HLA genotypes with clinical presentation and outcomes after immunosuppressive therapy in 544 AA patients. HLA class I allele loss was detected in 92 (22%) of the 412 patients tested, in whom there were 393 somatic HLA gene mutations and 40 instances of loss of heterozygosity. Most frequently affected was HLA-B*14:02, followed by HLA-A*02:01, HLA-B*40:02, HLA-B*08:01, and HLA-B*07:02. HLA-B*14:02, HLA-B*40:02, and HLA-B*07:02 were also overrepresented in AA. High-risk clonal evolution was correlated with HLA loss, HLA-B*14:02 genotype, and older age, which yielded a valid prediction model. In 2 patients, we traced monosomy 7 clonal evolution from preexisting clones harboring somatic mutations in HLA-A*02:01 and HLA-B*40:02. Loss of HLA-B*40:02 correlated with higher blood counts. HLA-B*07:02 and HLA-B*40:01 genotypes and their loss correlated with late-onset of AA. Our results suggest the presence of specific immune mechanisms of molecular pathogenesis with clinical implications. HLA genotyping and screening for HLA loss may be of value in the management of immune AA. This study was registered at clinicaltrials.gov as NCT00001964, NCT00061360, NCT00195624, NCT00260689, NCT00944749, NCT01193283, and NCT01623167.


Assuntos
Anemia Aplástica/genética , Genes MHC Classe I , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Mutação , Adolescente , Adulto , Alelos , Anemia Aplástica/imunologia , Evolução Clonal , Feminino , Deleção de Genes , Expressão Gênica , Antígenos HLA-A/imunologia , Antígenos HLA-B/imunologia , Humanos , Imunidade , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Haematologica ; 105(12): 2785-2794, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33256377

RESUMO

Myelodysplastic syndromes (MDS) are a group of clonal myeloid disorders characterized by cytopenia and a propensity to develop acute myeloid leukemia (AML). The management of lower-risk (LR) MDS with persistent cytopenias remains suboptimal. Eltrombopag (EPAG), a thrombopoietin receptor agonist, can improve platelet counts in LR-MDS and tri-lineage hematopoiesis in aplastic anemia (AA). We conducted a phase 2 dose modification study to investigate the safety and efficacy of EPAG in LR-MDS. EPAG dose was escalated from 50 mg/day, to a maximum of 150 mg/day over a period of 16 weeks. The primary efficacy endpoint was hematologic response at 16-20 weeks. Eleven of 25 (44%) patients responded; five and six patients had uni- or bi-lineage hematologic responses, respectively. The predictors of response were presence of a PNH clone, marrow hypocellularity, thrombocytopenia with or without other cytopenia, and elevated plasma thrombopoietin levels at study entry. The safety profile was consistent with previous EPAG studies in AA; no patients discontinued drug due to adverse events. Three patients developed reversible grade-3 liver toxicity and one patient had increased reticulin fibrosis. Ten patients discontinued EPAG after achieving a robust response (median time 16 months); four of them reinitiated EPAG due to declining counts, and all attained a second robust response. Six patients had disease progression not associated with expansion of mutated clones and no patient progressed to AML on study. In conclusion, EPAG was well-tolerated and effective in restoring hematopoiesis in patients with low to intermediate-1 risk MDS. This study was registered at clinicaltrials.gov as #NCT00932156.


Assuntos
Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Benzoatos/efeitos adversos , Hematopoese , Humanos , Hidrazinas/efeitos adversos , Leucemia Mieloide Aguda/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Pirazóis
12.
Blood Adv ; 4(8): 1700-1710, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32330244

RESUMO

There is no standard or widely effective treatment of patients with moderate aplastic anemia (MAA) or hypo-productive uni-lineage cytopenias (UC). Eltrombopag (EPAG), a small molecule thrombopoietin mimetic, has previously been shown to result in durable multi-lineage hematologic responses with low toxicity in patients with refractory severe aplastic anemia (SAA). Its safety and efficacy in MAA are unknown. This prospective phase 2 study enrolled previously untreated and treated MAA and UC patients with clinically relevant cytopenias. EPAG was administered at doses escalating from 50 to 300 mg/d. Hematologic responses were assessed at 16 to 20 weeks. Responding patients were continued on EPAG until reaching defined robust or stable blood counts. EPAG was reinstituted for relapse. Thirty-four patients were enrolled between 2012 and 2017, including 31 with MAA and 3 with UC. Seventeen patients responded in at least 1 eligible lineage by the primary end point. A striking improvement in anemia was observed in a patient with Diamond-Blackfan anemia. EPAG was well tolerated, and it was discontinued for robust or stable blood counts in 12 of 17 patients after a median of 8 months. A majority required re-initiation of EPAG for declining counts, and all regained response. Two of 34 patients developed non-chromosome 7 bone marrow cytogenetic abnormalities while taking EPAG, without dysplasia or increased blasts. Somatic mutation allele frequencies in cancer genes did not increase overall on EPAG. EPAG is a well-tolerated oral treatment of cytopenias in patients with MAA/UC. This trial was registered at www.clinicaltrials.gov as #NCT01328587.


Assuntos
Anemia Aplástica , Anemia Aplástica/tratamento farmacológico , Benzoatos/efeitos adversos , Humanos , Hidrazinas/efeitos adversos , Estudos Prospectivos , Pirazóis
13.
ESC Heart Fail ; 7(2): 639-644, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32155316

RESUMO

AIMS: Soluble tumour necrosis factor-α receptor 1 (sTNF-αR1) and interleukin-2 receptor α (sIL-2Rα) predict incident heart failure (HF) in the elderly population. However, the association of these biomarkers with HF in a multi-ethnic asymptomatic population is unclear. We aimed to investigate the association of sTNF-αR1 and sIL-2Rα with incident HF in a multi-ethnic population of middle age and older participants. METHODS AND RESULTS: The multi-ethnic study of atherosclerosis is a prospective population-based study of 6814 participants aged 45-84 years who were free of clinical cardiovascular disease at enrolment. We included 2869 participants with available sTNF-αR1 or sIL-2Rα level measurement at baseline multi-ethnic study of atherosclerosis exam (2000-2002). We used Cox proportional-hazards model to investigate the association between sTNF-αR1 and sIL-2Rα with incident HF after adjusting for traditional cardiovascular risk factors and coronary artery calcium score measured by cardiac computed tomography. Among the included participants, the mean (standard deviation) age was 61.6 (10.2) years and 46.7% were men. The median (interquartile range) sTNF-αR1 and sIL-2Rα were 1293 (1107-1547) and 901 (727-1154) pg/mL. During a median follow-up of 14.2 (interquartile range: 11.7-14.8) years, 130 participants developed HF. In multivariable analysis, the hazard ratio (95% confidence interval, P value) of incident HF for each standard deviation increment of log-transformed sTNF-αR1 and sIL-2Rα was 1.43 (1.21-1.7, P ≤ 0.001) and 1.26 (1.04-1.53, P = 0.02), respectively. Excluding participants with interim coronary heart disease, we found a statistically significant association between sTNF-αR1 and HF with hazard ratio of 1.39 (95% confidence interval: 1.11 to 1.74, P = 0.005) and sIL-2Rα and HF showing a hazard ratio of 1.39 (95% confidence interval: 1.09 to 1.76, P = 0.007). CONCLUSIONS: sTNF-αR1 and sIL-2Rα are associated with a higher risk of incident HF in a multi-ethnic cohort without a previous history of cardiovascular disease.


Assuntos
Insuficiência Cardíaca , Subunidade alfa de Receptor de Interleucina-2/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Idoso , Aterosclerose/epidemiologia , Feminino , Insuficiência Cardíaca/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
14.
Stat Methods Med Res ; 27(5): 1464-1475, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-27507288

RESUMO

Genetic association studies often collect information on secondary phenotypes related to the primary disease status. In many situations, the secondary phenotypes are only measured in subjects with the disease condition. It would be advantageous to model the primary trait and the secondary phenotype together if they share certain level of genetic heritability. We propose a family of multi-locus testing procedures to detect the composite association between a set of genetic markers and two traits (the primary trait and a secondary phenotype), in order to identify genes influencing both traits. The proposed test is derived from a random effect model with two variance components, with each presenting the genetic effect on one trait, and incorporates a model selection procedure for seeking the optimal model to represent the two sources of genetic effects. We conduct simulation studies to evaluate performance of the proposed procedure and apply the method to a genome-wide association study of prostate cancer with the Gleason score as the secondary phenotype.


Assuntos
Estudos de Associação Genética/métodos , Característica Quantitativa Herdável , Loci Gênicos/genética , Marcadores Genéticos , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Humanos , Masculino , Modelos Estatísticos , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Próstata/genética
15.
N Engl J Med ; 374(20): 1922-31, 2016 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-27192671

RESUMO

BACKGROUND: Genetic defects in telomere maintenance and repair cause bone marrow failure, liver cirrhosis, and pulmonary fibrosis, and they increase susceptibility to cancer. Historically, androgens have been useful as treatment for marrow failure syndromes. In tissue culture and animal models, sex hormones regulate expression of the telomerase gene. METHODS: In a phase 1-2 prospective study involving patients with telomere diseases, we administered the synthetic sex hormone danazol orally at a dose of 800 mg per day for a total of 24 months. The goal of treatment was the attenuation of accelerated telomere attrition, and the primary efficacy end point was a 20% reduction in the annual rate of telomere attrition measured at 24 months. The occurrence of toxic effects of treatment was the primary safety end point. Hematologic response to treatment at various time points was the secondary efficacy end point. RESULTS: After 27 patients were enrolled, the study was halted early, because telomere attrition was reduced in all 12 patients who could be evaluated for the primary end point; in the intention-to-treat analysis, 12 of 27 patients (44%; 95% confidence interval [CI], 26 to 64) met the primary efficacy end point. Unexpectedly, almost all the patients (11 of 12, 92%) had a gain in telomere length at 24 months as compared with baseline (mean increase, 386 bp [95% CI, 178 to 593]); in exploratory analyses, similar increases were observed at 6 months (16 of 21 patients; mean increase, 175 bp [95% CI, 79 to 271]) and 12 months (16 of 18 patients; mean increase, 360 bp [95% CI, 209 to 512]). Hematologic responses occurred in 19 of 24 patients (79%) who could be evaluated at 3 months and in 10 of 12 patients (83%) who could be evaluated at 24 months. Known adverse effects of danazol--elevated liver-enzyme levels and muscle cramps--of grade 2 or less occurred in 41% and 33% of the patients, respectively. CONCLUSIONS: In our study, treatment with danazol led to telomere elongation in patients with telomere diseases. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT01441037.).


Assuntos
Doenças da Medula Óssea/tratamento farmacológico , Danazol/uso terapêutico , Antagonistas de Estrogênios/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Fibrose Pulmonar/tratamento farmacológico , Telômero/efeitos dos fármacos , Administração Oral , Adolescente , Adulto , Idoso , Feminino , Cor de Cabelo/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Telomerase/genética , Telomerase/metabolismo , Telômero/ultraestrutura , Regulação para Cima , Adulto Jovem
16.
Lancet Haematol ; 3(1): e22-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26765645

RESUMO

BACKGROUND: T-cell large granular lymphocytic leukaemia (T-LGL) is a lymphoproliferative disease that presents with immune-mediated cytopenias and is characterised by clonal expansion of cytotoxic CD3+ CD8+ lymphocytes. Use of methotrexate, ciclosporin, or cyclophosphamide as first therapy improves cytopenias in 50% of patients, but long-term use of these can lead to toxicity. We aimed to explore the activity and safety of alemtuzumab, an anti-CD52 monoclonal antibody, in patients with T-LGL. METHODS: We did this single-arm, phase 2 trial in consecutively enrolled adults with T-LGL referred to the National Institutes of Health in Bethesda, MD, USA. Alemtuzumab was given intravenously at 10 mg per day for 10 days. The primary endpoint was haematological response at 3 months after infusion. A complete response was defined as normalisation of all affected lineages, and a partial response was defined in neutropenic patients as 100% increase in the absolute neutrophil count to more than 5 × 10(8) cells per L, and in those with anaemia, as any increase in haemoglobin of 20 g/L or higher observed in at least two serial measurements 1 week apart and sustained for 1 month or longer without exogenous growth factors support or transfusions. Analysis was by intention to treat. We report results from the first stage of this Simon two-stage design trial; enrolment into the second stage is continuing. This study is registered with ClinicalTrials.gov, number NCT00345345. FINDINGS: From Oct 1, 2006, to March 1, 2015, we enrolled 25 patients with T-LGL. 14 patients (56%; 95% CI 35-76) had a haematological response at 3 months. Four patients with associated myelodysplastic syndrome and two who had received haemopoietic stem cell transplantation had either no response or were not evaluable, meaning 14 (74% [49-91]) of the 19 patients with classic T-LGL responded. All patients had an infusion reaction (24 [96%] patients grade 1-2, one [4%] patient grade 3), which improved with symptomatic therapy. All patients developed lymphopenia, with 22 (88%) patients having grade 3 or 4 lymphopenia. The other most common grade 3 and 4 adverse events were leukopenia (eight [32%]) and neutropenic infections (five [20%]). Seven patients died; all were non-responders. INTERPRETATION: This is the largest and only prospective study of alemtuzumab in patients with T-LGL. The activity reported with a single course of a lymphocytotoxic drug in patients with mainly relapsed and refractory disease suggests that haematological response can be achieved without continued use of oral immunosuppression. FUNDING: National Heart, Lung, and Blood Institute.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Leucemia Linfocítica Granular Grande/tratamento farmacológico , Idoso , Alemtuzumab , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Indução de Remissão , Resultado do Tratamento
17.
Eur Heart J Cardiovasc Imaging ; 17(9): 1044-53, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26758407

RESUMO

AIMS: Longitudinal determinants of aortic stiffness (AS) measured by magnetic resonance imaging (MRI) have not been assessed in a large community-based population. Our aim was to examine the determinants of change in thoracic AS over 10 years of follow-up in a multi-ethnic population of individuals 45 years of age and older measured by MRI. METHODS AND RESULTS: We studied 1160 participants (mean age = 60 ± 9 years at baseline, 45% male) with aortic MRI at both the MESA Year 0 and Year 10 examinations. Ascending and descending aorta distensibility (AAD/DAD) and aortic arch pulse-wave velocity (PWV) were measured using MRI. Determinants of the change in AS parameters over 10 years were assessed using linear regression adjusted for baseline values, demographic variables, baseline risk factors and change in risk factors, and chronic risk exposure. AAD and DAD decreased slightly (5% decrease in median for AAD: 1.33-1.26 mmHg(-1) · 10(-3), P = 0.008; 5% decrease in median for DAD: 1.73-1.64 mmHg(-1) · 10(-3), P < 0.001), and PWV increased over 10 years (18% increase in median: 6.8-8.0 m/s P < 0.001). Baseline age was related to a reduction in AAD and DAD and an increase in PWV throughout the follow-up period. Baseline and change in mean blood pressure and continued smoking were associated with a reduction in AAD and an increase in PWV. Furthermore, baseline heart rate was also related to a reduction in AAD and DAD. Blood pressure normalization was related to less aortic stiffening throughout the follow-up period. CONCLUSIONS: In our longitudinal, community-based cohort study of adult individuals aged 45 years or greater, greater mean blood pressure and a history of smoking history were associated with increased aortic stiffening over 10 years as assessed by MRI.


Assuntos
Aorta Torácica/diagnóstico por imagem , Doenças Cardiovasculares/diagnóstico , Etnicidade/estatística & dados numéricos , Hipertensão/diagnóstico , Imagem Cinética por Ressonância Magnética/métodos , Rigidez Vascular/fisiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Aorta Torácica/patologia , Determinação da Pressão Arterial , Doenças Cardiovasculares/etnologia , Feminino , Seguimentos , Humanos , Hipertensão/etnologia , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise de Onda de Pulso , Estudos Retrospectivos , Medição de Risco , Distribuição por Sexo , Fatores de Tempo
18.
N Engl J Med ; 373(1): 35-47, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26132940

RESUMO

BACKGROUND: In patients with acquired aplastic anemia, destruction of hematopoietic cells by the immune system leads to pancytopenia. Patients have a response to immunosuppressive therapy, but myelodysplastic syndromes and acute myeloid leukemia develop in about 15% of the patients, usually many months to years after the diagnosis of aplastic anemia. METHODS: We performed next-generation sequencing and array-based karyotyping using 668 blood samples obtained from 439 patients with aplastic anemia. We analyzed serial samples obtained from 82 patients. RESULTS: Somatic mutations in myeloid cancer candidate genes were present in one third of the patients, in a limited number of genes and at low initial variant allele frequency. Clonal hematopoiesis was detected in 47% of the patients, most frequently as acquired mutations. The prevalence of the mutations increased with age, and mutations had an age-related signature. DNMT3A-mutated and ASXL1-mutated clones tended to increase in size over time; the size of BCOR- and BCORL1-mutated and PIGA-mutated clones decreased or remained stable. Mutations in PIGA and BCOR and BCORL1 correlated with a better response to immunosuppressive therapy and longer and a higher rate of overall and progression-free survival; mutations in a subgroup of genes that included DNMT3A and ASXL1 were associated with worse outcomes. However, clonal dynamics were highly variable and might not necessarily have predicted the response to therapy and long-term survival among individual patients. CONCLUSIONS: Clonal hematopoiesis was prevalent in aplastic anemia. Some mutations were related to clinical outcomes. A highly biased set of mutations is evidence of Darwinian selection in the failed bone marrow environment. The pattern of somatic clones in individual patients over time was variable and frequently unpredictable. (Funded by Grant-in-Aid for Scientific Research and others.).


Assuntos
Anemia Aplástica/genética , Hematopoese/genética , Mutação , Fatores Etários , Idoso , Anemia Aplástica/sangue , Anemia Aplástica/mortalidade , Células Clonais , Feminino , Humanos , Cariotipagem , Leucemia Mieloide Aguda/genética , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Análise de Sequência de DNA
19.
Atherosclerosis ; 239(2): 412-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25682041

RESUMO

BACKGROUND: The role of atherosclerosis in the progression of global left ventricular dysfunction and cardiovascular events has been well recognized. Left ventricular (LV) dyssynchrony is a measure of regional myocardial dysfunction. Our objective was to investigate the relationship of subclinical atherosclerosis with mechanical LV dyssynchrony in a population-based asymptomatic multi-ethnic cohort. METHODS AND RESULTS: Participants of the Multi-Ethnic Study of Atherosclerosis (MESA) at exam 5 were evaluated using 1.5T cardiac magnetic resonance (CMR) imaging, carotid ultrasound (n = 2062) for common carotid artery (CCA) and internal carotid artery (ICA) intima-media thickness (IMT), and cardiac computed tomography (n = 2039) for coronary artery calcium (CAC) assessment (Agatston method). Dyssynchrony indices were defined as the standard deviation of time to peak systolic circumferential strain (SD-TPS) and the difference between maximum and minimum (max-min) time to peak strain using harmonic phase imaging in 12 segments (3-slices × 4 segments). Multivariable regression analyses were performed to assess associations after adjusting for participant demographics, cardiovascular risk factors, LV mass, and ejection fraction. In multivariable analyses, SD-TPS was significantly related to measures of atherosclerosis, including CCA-IMT (8.7 ms/mm change in IMT, p = 0.020), ICA-IMT (19.2 ms/mm change in IMT, p < 0.001), carotid plaque score (1.2 ms/unit change in score, p < 0.001), and log transformed CAC+1 (0.66 ms/unit log-CAC+1, p = 0.018). These findings were consistent with other parameter of LV dyssynchrony i.e. max-min. CONCLUSION: In the MESA cohort, measures of atherosclerosis are associated with parameters of subclinical LV dyssynchrony in the absence of clinical coronary event and left-bundle-branch block.


Assuntos
Aterosclerose/fisiopatologia , Calcinose/fisiopatologia , Artérias Carótidas/patologia , Artéria Carótida Primitiva/patologia , Espessura Intima-Media Carotídea , Placa Aterosclerótica/patologia , Disfunção Ventricular Esquerda/patologia , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/complicações , Bloqueio de Ramo , Cálcio/metabolismo , Doenças Cardiovasculares/complicações , Feminino , Gadolínio/química , Taxa de Filtração Glomerular , Ventrículos do Coração/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Miocárdio/patologia , Placa Aterosclerótica/complicações , Estudos Prospectivos , Fatores de Risco , Disfunção Ventricular Esquerda/complicações
20.
Heart ; 101(1): 58-64, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25381326

RESUMO

OBJECTIVE: Heart failure (HF) is a leading cause of mortality especially in older populations. Early detection of high-risk individuals is imperative for primary prevention. The purpose of this study was to develop a HF risk model from a population without clinical cardiac disease. METHODS: The Multi-Ethnic Study of Atherosclerosis is a multicentre observational cohort study following 6814 subjects (mean age 62±10 years; 47% men) who were free of clinical cardiovascular disease at baseline. Median follow-up was 4.7 years. HF events developed in 176 participants. Cox proportional hazards models and regression coefficients were used to determine independent risk factors and generate a 5-year risk score for incident HF. Bootstrapping with bias correction was used for internal validation. RESULTS: Independent predictors for HF (HR, p value) were age (1.30 (1.10 to 1.50) per 10 years), male gender (2.27 (1.53 to 3.36)), current smoking (1.97 (1.15 to 3.36)), body mass index (1.40 (1.10 to 1.80) per 5 kg/m(2)), systolic blood pressure (1.10 (1.00 to 1.10) per 10 mm Hg), heart rate (1.30) (1.10 to 1.40) per 10 bpm), diabetes (2.27 (1.48 to 3.47)), N-terminal pro-B-type natriuretic peptide (NT proBNP) (2.48 (2.16 to 2.84) per unit log increment) and left ventricular mass index (1.40 (1.30 to 1.40) per 10 g/m(2)). A parsimonious model based on age, gender, body mass index, smoking status, systolic blood pressure, heart rate, diabetes and NT proBNP natriuretic peptide predicted incident HF risk with a c-statistic of 0.87. CONCLUSIONS: A clinical algorithm based on risk factors readily available in the primary care setting can used to identify individuals with high likelihood of developing HF without pre-existing cardiac disease.


Assuntos
Asiático , Aterosclerose/etnologia , Negro ou Afro-Americano , Insuficiência Cardíaca/etnologia , Hispânico ou Latino , População Branca , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Aterosclerose/diagnóstico , Distribuição de Qui-Quadrado , China/epidemiologia , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologia
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