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1.
Calcif Tissue Int ; 114(1): 60-73, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37758867

RESUMO

BACKGROUND: Sarcopenic Obesity is the co-existence of increased adipose tissue (obesity) and decreased muscle mass or strength (sarcopenia) and is associated with worse outcomes than obesity alone. The new EASO/ESPEN consensus provides a framework to standardize its definition. This study sought to evaluate whether there are preliminary differences observed in weight loss or physical function in older adults with and without sarcopenic obesity taking part in a multicomponent weight loss intervention using these new definitions. METHODS: A 6-month, non-randomized, non-blinded, single-arm pilot study was conducted from 2018 to 2020 in adults ≥ 65 years with a body mass index (BMI) ≥ 30 kg/m2. Weekly dietitian visits and twice-weekly physical therapist-led exercise classes were delivered using telemedicine. We conducted a secondary retrospective analysis of the parent study (n = 53 enrolled, n = 44 completers) that investigated the feasibility of a technology-based weight management intervention in rural older adults with obesity. Herein, we applied five definitions of sarcopenic obesity (outlined in the consensus) to ascertain whether the response to the intervention differed among those with and without sarcopenic obesity. Primary outcomes evaluated included weight loss and physical function (30-s sit-to-stand). RESULTS: In the parent study, mean weight loss was - 4.6 kg (95% CI - 3.6, - 5.6; p < 0.001). Physical function measures of 30-s sit-to-stand showed a mean increase of 3.1 in sit-to-stand repetitions (+ 1.9, + 4.3; p < 0.001). In this current analysis, there was a significant decrease in weight and an increase in repetitions between baseline and follow-up within each group of individuals with and without sarcopenia for each of the proposed definitions. However, we did not observe any significant differences in the changes between groups from baseline to follow-up. CONCLUSIONS: The potential lack of significant differences in weight loss or physical function between older adults with and without sarcopenic obesity participating in a weight loss intervention may suggest that well-designed, multicomponent interventions can lead to similar outcomes irrespective of sarcopenia status in persons with obesity. Fully powered randomized clinical trials are critically needed to confirm these preliminary results.


Assuntos
Sarcopenia , Humanos , Idoso , Sarcopenia/complicações , Sarcopenia/terapia , Força Muscular , Estudos Retrospectivos , Projetos Piloto , Obesidade/complicações , Obesidade/terapia , Redução de Peso
2.
Eur Spine J ; 32(10): 3497-3504, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37422607

RESUMO

PURPOSE: Cervical artery dissection (CeAD), which includes both vertebral artery dissection (VAD) and carotid artery dissection (CAD), is the most serious safety concern associated with cervical spinal manipulation (CSM). We evaluated the association between CSM and CeAD among US adults. METHODS: Through analysis of health claims data, we employed a case-control study with matched controls, a case-control design in which controls were diagnosed with ischemic stroke, and a case-crossover design in which recent exposures were compared to exposures in the same case that occurred 6-7 months earlier. We evaluated the association between CeAD and the 3-level exposure, CSM versus office visit for medical evaluation and management (E&M) versus neither, with E&M set as the referent group. RESULTS: We identified 2337 VAD cases and 2916 CAD cases. Compared to population controls, VAD cases were 0.17 (95% CI 0.09 to 0.32) times as likely to have received CSM in the previous week as compared to E&M. In other words, E&M was about 5 times more likely than CSM in the previous week in cases, relative to controls. CSM was 2.53 (95% CI 1.71 to 3.68) times as likely as E&M in the previous week among individuals with VAD than among individuals experiencing a stroke without CeAD. In the case-crossover study, CSM was 0.38 (95% CI 0.15 to 0.91) times as likely as E&M in the week before a VAD, relative to 6 months earlier. In other words, E&M was approximately 3 times more likely than CSM in the previous week in cases, relative to controls. Results for the 14-day and 30-day timeframes were similar to those at one week. CONCLUSION: Among privately insured US adults, the overall risk of CeAD is very low. Prior receipt of CSM was more likely than E&M among VAD patients as compared to stroke patients. However, for CAD patients as compared to stroke patients, as well as for both VAD and CAD patients in comparison with population controls and in case-crossover analysis, prior receipt of E&M was more likely than CSM.


Assuntos
Manipulação da Coluna , Acidente Vascular Cerebral , Dissecação da Artéria Vertebral , Humanos , Adulto , Manipulação da Coluna/efeitos adversos , Estudos de Casos e Controles , Estudos Cross-Over , Dissecação da Artéria Vertebral/epidemiologia , Artérias , Fatores de Risco
3.
Carcinogenesis ; 43(5): 430-436, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-35259245

RESUMO

Cytomegalovirus (CMV) is a highly prevalent human herpes virus that exerts a strong influence on immune repertoire which may influence cancer risk. We have tested whether CMV immunoglobulin G (IgG) serostatus is associated with immune cell proportions (n = 132 population controls), human papillomavirus (HPV) co-infection and head and neck cancer risk (n = 184 cancer cases and 188 controls) and patient survival. CMV status was not associated with the proportion of Natural Killer cells, B cells or the neutrophil-to-lymphocyte ratio. However, CD8+ T cells increased with increasing categories of IgG titers (P =1.7 × 10-10), and titers were inversely associated with the CD4:CD8 ratio (P = 5.6 × 10-5). Despite these differences in T cell proportions, CMV was not associated with HPV16 co-infection. CMV seropositivity was similar in cases (52%) and controls (47%) and was not associated with patient survival (hazard ratio [HR] 1.14, 95% confidence interval [CI]: 0.70 to 1.86). However, those patients with the highest titers had the worst survival (HR 1.91, 95% CI: 1.13 to 3.23). Tumor-based data from The Cancer Genome Atlas demonstrated that the presence of CMV transcripts was associated with worse patient survival (HR 1.79, 95% CI: 0.96 to 2.78). These findings confirm that a history of CMV infection alters T cell proportions, but this does not translate to HPV16 co-infection or head and neck cancer risk. Our data suggest that high titers and active CMV virus in the tumor environment may confer worse survival.


Assuntos
Coinfecção , Infecções por Citomegalovirus , Neoplasias de Cabeça e Pescoço , Linfócitos T CD8-Positivos , Coinfecção/complicações , Citomegalovirus , Infecções por Citomegalovirus/complicações , Humanos , Imunoglobulina G
4.
BMC Geriatr ; 22(1): 917, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36447166

RESUMO

BACKGROUND: Cervical artery dissection and subsequent ischemic stroke is the most serious safety concern associated with cervical spinal manipulation. METHODS: We evaluated the association between cervical spinal manipulation and cervical artery dissection among older Medicare beneficiaries in the United States. We employed case-control and case-crossover designs in the analysis of claims data for individuals aged 65+, continuously enrolled in Medicare Part A (covering hospitalizations) and Part B (covering outpatient encounters) for at least two consecutive years during 2007-2015. The primary exposure was cervical spinal manipulation; the secondary exposure was a clinical encounter for evaluation and management for neck pain or headache. We created a 3-level categorical variable, (1) any cervical spinal manipulation, 2) evaluation and management but no cervical spinal manipulation and (3) neither cervical spinal manipulation nor evaluation and management. The primary outcomes were occurrence of cervical artery dissection, either (1) vertebral artery dissection or (2) carotid artery dissection. The cases had a new primary diagnosis on at least one inpatient hospital claim or primary/secondary diagnosis for outpatient claims on at least two separate days. Cases were compared to 3 different control groups: (1) matched population controls having at least one claim in the same year as the case; (2) ischemic stroke controls without cervical artery dissection; and (3) case-crossover analysis comparing cases to themselves in the time period 6-7 months prior to their cervical artery dissection. We made each comparison across three different time frames: up to (1) 7 days; (2) 14 days; and (3) 30 days prior to index event. RESULTS: The odds of cervical spinal manipulation versus evaluation and management did not significantly differ between vertebral artery dissection cases and any of the control groups at any of the timepoints (ORs 0.84 to 1.88; p > 0.05). Results for carotid artery dissection cases were similar. CONCLUSION: Among Medicare beneficiaries aged 65 and older who received cervical spinal manipulation, the risk of cervical artery dissection is no greater than that among control groups.


Assuntos
Doenças das Artérias Carótidas , AVC Isquêmico , Manipulação da Coluna , Dissecação da Artéria Vertebral , Humanos , Idoso , Estados Unidos/epidemiologia , Manipulação da Coluna/efeitos adversos , Revisão da Utilização de Seguros , Dissecação da Artéria Vertebral/epidemiologia , Dissecação da Artéria Vertebral/etiologia , Dissecação da Artéria Vertebral/terapia , Medicare , Artérias
5.
BMC Geriatr ; 21(1): 44, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33435877

RESUMO

BACKGROUND: Older adults with obesity residing in rural areas have reduced access to weight management programs. We determined the feasibility, acceptability and preliminary outcomes of an integrated technology-based health promotion intervention in rural-living, older adults using remote monitoring and synchronous video-based technology. METHODS: A 6-month, non-randomized, non-blinded, single-arm study was conducted from October 2018 to May 2020 at a community-based aging center of adults aged ≥65 years with a body mass index (BMI) ≥30 kg/m2. Weekly dietitian visits focusing on behavior therapy and caloric restriction and twice-weekly physical therapist-led group strength, flexibility and balance training classes were delivered using video-conferencing to participants in their homes. Participants used a Fitbit Alta HR for remote monitoring with data feedback provided by the interventionists. An aerobic activity prescription was provided and monitored. RESULTS: Mean age was 72.9±3.9 years (82% female). Baseline anthropometric measures of weight, BMI, and waist circumference were 97.8±16.3 kg, 36.5±5.2 kg/m2, and 115.5±13.0 cm, respectively. A total of 142 participants were screened (n=27 ineligible), and 53 consented. There were nine dropouts (17%). Overall satisfaction with the trial (4.7+ 0.6, scale: 1 (low) to 5 (high)) and with Fitbit (4.2+ 0.9) were high. Fitbit was worn an average of 81.7±19.3% of intervention days. In completers, mean weight loss was 4.6±3.5 kg or 4.7±3.5% (p< 0.001). Physical function measures of 30-s sit-to-stand repetitions increased from 13.5±5.7 to 16.7±5.9 (p< 0.001), 6-min walk improved by 42.0±77.3 m (p=0.005) but no differences were observed in gait speed or grip strength. Subjective measures of late-life function improved (3.4±4.7 points, p< 0.001). CONCLUSIONS: A technology-based obesity intervention is feasible and acceptable to older adults with obesity and may lead to weight loss and improved physical function. CLINICAL TRIAL REGISTRATION: Registered on Clinicaltrials.gov # NCT03104205 . Registered on April 7, 2017. First participant enrolled on October 1st, 2018.


Assuntos
Obesidade , Redução de Peso , Idoso , Índice de Massa Corporal , Estudos de Viabilidade , Feminino , Humanos , Masculino , Obesidade/diagnóstico , Obesidade/epidemiologia , Obesidade/terapia , Tecnologia
6.
J Manipulative Physiol Ther ; 44(3): 177-185, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33849727

RESUMO

OBJECTIVE: Spinal manipulation (SM) is recommended for first-line treatment of patients with low back pain. Inadequate access to SM may result in inequitable spine care for older US adults, but the supply of clinicians who provide SM under Medicare is uncertain. The purpose of this study was to measure temporal trends and geographic variations in the supply of clinicians who provide SM to Medicare beneficiaries. METHODS: Medicare is a US government-administered health insurance program that provides coverage primarily for older adults and people with disabilities. We used a serial cross-sectional design to examine Medicare administrative data from 2007 to 2015 for SM services identified by procedure code. We identified unique providers by National Provider Identifier and distinguished between chiropractors and other specialties by Physician Specialty Code. We calculated supply as the number of providers per 100 000 beneficiaries, stratified by geographic location and year. RESULTS: Of all clinicians who provide SM to Medicare beneficiaries, 97% to 98% are doctors of chiropractic. The geographic supply of doctors of chiropractic providing SM services in 2015 ranged from 20/100 000 in the District of Columbia to 260/100 000 in North Dakota. The supply of other specialists performing the same services ranged from fewer than 1/100 000 in 11 states to 8/100 000 in Colorado. Nationally, the number of Medicare-active chiropractors declined from 47 102 in 2007 to 45 543 in 2015. The count of other clinicians providing SM rose from 700 in 2007 to 1441 in 2015. CONCLUSION: Chiropractors constitute the vast majority of clinicians who bill for SM services to Medicare beneficiaries. The supply of Medicare-active SM providers varies widely by state. The overall supply of SM providers under Medicare is declining, while the supply of nonchiropractors who provide SM is growing.


Assuntos
Dor Lombar/reabilitação , Manipulação Quiroprática/tendências , Manipulação da Coluna/tendências , Medicare/tendências , Idoso , Quiroprática/organização & administração , Estudos Transversais , Humanos , Dor Lombar/economia , Masculino , Manipulação Quiroprática/economia , Manipulação da Coluna/economia , Medicare/economia , Estados Unidos
7.
BMC Bioinformatics ; 21(1): 108, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183722

RESUMO

BACKGROUND: DNA methylation (DNAm) is an epigenetic regulator of gene expression programs that can be altered by environmental exposures, aging, and in pathogenesis. Traditional analyses that associate DNAm alterations with phenotypes suffer from multiple hypothesis testing and multi-collinearity due to the high-dimensional, continuous, interacting and non-linear nature of the data. Deep learning analyses have shown much promise to study disease heterogeneity. DNAm deep learning approaches have not yet been formalized into user-friendly frameworks for execution, training, and interpreting models. Here, we describe MethylNet, a DNAm deep learning method that can construct embeddings, make predictions, generate new data, and uncover unknown heterogeneity with minimal user supervision. RESULTS: The results of our experiments indicate that MethylNet can study cellular differences, grasp higher order information of cancer sub-types, estimate age and capture factors associated with smoking in concordance with known differences. CONCLUSION: The ability of MethylNet to capture nonlinear interactions presents an opportunity for further study of unknown disease, cellular heterogeneity and aging processes.


Assuntos
Metilação de DNA , Aprendizado Profundo , Interface Usuário-Computador , Envelhecimento/genética , Ilhas de CpG , Humanos , Neoplasias/genética , Neoplasias/patologia
8.
Cancer ; 124(7): 1350-1357, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29266172

RESUMO

BACKGROUND: A history of proliferative breast disease with atypia (PBDA) may be indicative of an increased risk not just of breast cancer but also of a more aggressive form of breast cancer. METHODS: Multifocal breast cancer (MFBC), defined as 2 or more tumors in the same breast upon a diagnosis of cancer, is associated with a poorer prognosis than unifocal (single-tumor) breast cancer. PBDA, including atypical ductal hyperplasia and atypical lobular hyperplasia, is a known risk factor for breast cancer. Using New Hampshire Mammography Network data collected for 3567 women diagnosed with incident breast cancer from 2004 to 2014, this study assessed the risk of MFBC associated with a previous diagnosis of PBDA. RESULTS: Women with a history of PBDA were found to be twice as likely to be subsequently diagnosed with MFBC as women with no history of benign breast disease (BBD; odds ratio [OR], 2.23; 95% confidence interval [CI], 1.08-4.61). Ductal carcinoma in situ on initial biopsy was associated with a 2-fold increased risk of MFBC in comparison with invasive cancer (OR, 2.13; 95% CI, 1.58-2.88). BBD and proliferative BBD without atypia were not associated with MFBC. CONCLUSIONS: Women with a history of previous PBDA may be at increased risk for MFBC. Women with a history of PBDA may benefit from additional presurgical clinical workup. Cancer 2018;124:1350-7. © 2017 American Cancer Society.


Assuntos
Doenças Mamárias/complicações , Neoplasias da Mama/etiologia , Carcinoma Intraductal não Infiltrante/etiologia , Predisposição Genética para Doença , Hiperplasia/etiologia , Lesões Pré-Cancerosas/etiologia , Idoso , Doenças Mamárias/genética , Doenças Mamárias/patologia , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Seguimentos , Humanos , Hiperplasia/patologia , Estudos Longitudinais , Mamografia , Pessoa de Meia-Idade , Invasividade Neoplásica , Lesões Pré-Cancerosas/patologia , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco
10.
Blood ; 120(13): 2658-68, 2012 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-22889761

RESUMO

Sequestration in the bone marrow niche may allow leukemic stem cells to evade exposure to drugs. Because the CXCR4/SDF-1 axis is an important mechanism of leukemic stem cell interaction with marrow stroma, we tested whether plerixafor, an antagonist of CXCR4, may dislodge chronic myeloid leukemia (CML) cells from the niche, sensitizing them to tyrosine kinase inhibitors. We initially treated mice with retrovirally induced CML-like disease with imatinib plus plerixafor. Plerixafor mobilized CXCR4(+) cells, but no difference was observed in leukemia burden, possibly reflecting insufficient disease control by imatinib. In a second series of experiments, we tested the combination of plerixafor with dasatinib in the same as well as an attenuated CML model. Despite much improved leukemia control, plerixafor failed to reduce leukemia burden over dasatinib alone. In addition, mice receiving plerixafor had an increased incidence of neurologic symptoms in association with CNS infiltration by BCR-ABL-expressing cells. We conclude that plerixafor is ineffective in reducing leukemia burden in this model but promotes CNS infiltration. Beneficial effects of combining tyrosine kinase inhibitors with plerixafor may be observed in a situation of minimal residual disease, but caution is warranted when disease control is incomplete.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Compostos Heterocíclicos/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Doenças do Sistema Nervoso/induzido quimicamente , Inibidores de Proteínas Quinases/uso terapêutico , Receptores CXCR4/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Benzamidas , Benzilaminas , Western Blotting , Linhagem Celular Tumoral , Quimiocina CXCL12/metabolismo , Ciclamos , Dasatinibe , Feminino , Citometria de Fluxo , Mesilato de Imatinib , Técnicas Imunoenzimáticas , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Camundongos , Camundongos Endogâmicos BALB C , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/patologia , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Receptores CXCR4/antagonistas & inibidores , Tiazóis/uso terapêutico
11.
Blood ; 120(2): 323-34, 2012 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-22653977

RESUMO

Bone marrow failure is a nearly universal complication of Fanconi anemia. The proteins encoded by FANC genes are involved in DNA damage responses through the formation of a multisubunit nuclear complex that facilitates the E3 ubiquitin ligase activity of FANCL. However, it is not known whether loss of E3 ubiquitin ligase activity accounts for the hematopoietic stem cell defects characteristic of Fanconi anemia. Here we provide evidence that FANCL increases the activity and expression of ß-catenin, a key pluripotency factor in hematopoietic stem cells. We show that FANCL ubiquitinates ß-catenin with atypical ubiquitin chain extension known to have nonproteolytic functions. Specifically, ß-catenin modified with lysine-11 ubiquitin chain extension efficiently activates a lymphocyte enhancer-binding factor-T cell factor reporter. We also show that FANCL-deficient cells display diminished capacity to activate ß-catenin leading to reduced transcription of Wnt-responsive targets c-Myc and Cyclin D1. Suppression of FANCL expression in normal human CD34(+) stem and progenitor cells results in fewer ß-catenin active cells and inhibits expansion of multilineage progenitors. Together, these results suggest that diminished Wnt/ß-catenin signaling may be an underlying molecular defect in FANCL-deficient hematopoietic stem cells leading to their accelerated loss.


Assuntos
Proteína do Grupo de Complementação L da Anemia de Fanconi/metabolismo , beta Catenina/metabolismo , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Ciclina D1/metabolismo , Anemia de Fanconi/etiologia , Anemia de Fanconi/genética , Anemia de Fanconi/metabolismo , Anemia de Fanconi/patologia , Proteína do Grupo de Complementação C da Anemia de Fanconi/deficiência , Proteína do Grupo de Complementação C da Anemia de Fanconi/genética , Proteína do Grupo de Complementação C da Anemia de Fanconi/metabolismo , Proteína do Grupo de Complementação L da Anemia de Fanconi/deficiência , Proteína do Grupo de Complementação L da Anemia de Fanconi/genética , Sangue Fetal/citologia , Sangue Fetal/metabolismo , Células HEK293 , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Camundongos , Camundongos Knockout , Modelos Biológicos , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/patologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Fatores de Transcrição TCF/metabolismo , Ubiquitinação , beta Catenina/química
12.
Blood ; 118(24): 6392-8, 2011 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-21860020

RESUMO

Proinflammatory cytokines such as TNFα are elevated in patients with myeloproliferative neoplasms (MPN), but their contribution to disease pathogenesis is unknown. Here we reveal a central role for TNFα in promoting clonal dominance of JAK2(V617F) expressing cells in MPN. We show that JAK2(V617F) kinase regulates TNFα expression in cell lines and primary MPN cells and TNFα expression is correlated with JAK2(V617F) allele burden. In clonogenic assays, normal controls show reduced colony formation in the presence of TNFα while colony formation by JAK2(V617F)-positive progenitor cells is resistant or stimulated by exposure to TNFα. Ectopic JAK2(V617F) expression confers TNFα resistance to normal murine progenitor cells and overcomes inherent TNFα hypersensitivity of Fanconi anemia complementation group C deficient progenitors. Lastly, absence of TNFα limits clonal expansion and attenuates disease in a murine model of JAK2(V617F)-positive MPN. Altogether our data are consistent with a model where JAK2(V617F) promotes clonal selection by conferring TNFα resistance to a preneoplastic TNFα sensitive cell, while simultaneously generating a TNFα-rich environment. Mutations that confer resistance to environmental stem cell stressors are a recognized mechanism of clonal selection and leukemogenesis in bone marrow failure syndromes and our data suggest that this mechanism is also critical to clonal selection in MPN.


Assuntos
Transformação Celular Neoplásica/metabolismo , Janus Quinase 2/metabolismo , Transtornos Mieloproliferativos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Substituição de Aminoácidos , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Proteína do Grupo de Complementação C da Anemia de Fanconi/genética , Proteína do Grupo de Complementação C da Anemia de Fanconi/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/genética , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa/sangue , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa/tratamento farmacológico , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa/genética , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Camundongos , Camundongos Knockout , Proteínas Mutantes/metabolismo , Células Progenitoras Mieloides/metabolismo , Transtornos Mieloproliferativos/sangue , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Mutação Puntual , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo , Fator de Necrose Tumoral alfa/genética
13.
Nutrients ; 15(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38068805

RESUMO

BACKGROUND: The role of protein in glucose homeostasis has demonstrated conflicting results. However, little research exists on its impact following weight loss. This study examined the impact of protein supplementation on glucose homeostasis in older adults >65 years with obesity seeking to lose weight. METHODS: A 12-week, nonrandomized, parallel group intervention of protein (PG) and nonprotein (NPG) arms for 28 older rural adults (body mass index (BMI) ≥ 30 kg/m2) was conducted at a community aging center. Both groups received twice weekly physical therapist-led group strength training classes. The PG consumed a whey protein supplement three times per week, post-strength training. Primary outcomes included pre/post-fasting glucose, insulin, inflammatory markers, and homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: Mean age and baseline BMI were 72.9 ± 4.4 years and 37.6 ± 6.9 kg/m2 in the PG and 73.0 ± 6.3 and 36.6 ± 5.5 kg/m2 in the NPG, respectively. Mean weight loss was -3.45 ± 2.86 kg in the PG and -5.79 ± 3.08 kg in the NPG (p < 0.001). There was a smaller decrease in pre- vs. post-fasting glucose levels (PG: -4 mg ± 13.9 vs. NPG: -12.2 ± 25.8 mg/dL; p = 0.10), insulin (-7.92 ± 28.08 vs. -46.7 ± 60.8 pmol/L; p = 0.01), and HOMA-IR (-0.18 ± 0.64 vs. -1.08 ± 1.50; p = 0.02) in the PG compared to the NPG. CONCLUSIONS: Protein supplementation during weight loss demonstrated a smaller decrease in insulin resistance compared to the NPG, suggesting protein may potentially mitigate beneficial effects of exercise on glucose homeostasis.


Assuntos
Resistência à Insulina , Humanos , Idoso , Insulina/farmacologia , Glucose/farmacologia , Suplementos Nutricionais , Homeostase , Redução de Peso , Glicemia/metabolismo , Índice de Massa Corporal
14.
Gerontechnology ; 22(1)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38116325

RESUMO

Background: Older adults frequently participate in behavior change studies, yet it is not clear how to quantify a potential relationship between their perception of the intervention and its efficacy. Research Aim: We assessed the relationship between participant sentiment toward the intervention from follow-up interviews with physical activity and questionnaires for the perception of health. Methods: Sentiment was calculated using the transcripts of exit interviews through a bag of words approach defined as the sum of positive and negative words in 28 older adults with obesity (body mass index ≥30kg/m2). Results: Mean age was 73 years (82% female), and 54% lost ≥5% weight loss. Through linear regression we describe a significant association between positive sentiment about the intervention and weight loss; positive sentiment on technology and change in PROMIS-10 physical health and reduced physical activity time, while controlling for sex and age. Conclusions: This analysis demonstrates that sentiment analysis and natural language processing in program review identified an association between perception and topics with clinical outcomes.

15.
Metabolites ; 13(7)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37512560

RESUMO

Caloric restriction and aerobic and resistance exercise are safe and effective lifestyle interventions for achieving weight loss in the obese older population (>65 years) and may improve physical function and quality of life. However, individual responses are heterogeneous. Our goal was to explore the use of untargeted metabolomics to identify metabolic phenotypes associated with achieving weight loss after a multi-component weight loss intervention. Forty-two older adults with obesity (body mass index, BMI, ≥30 kg/m2) participated in a six-month telehealth-based weight loss intervention. Each received weekly dietitian visits and twice-weekly physical therapist-led group strength training classes with a prescription for aerobic exercise. We categorized responders' weight loss using a 5% loss of initial body weight as a cutoff. Baseline serum samples were analyzed to determine the variable importance to the projection (VIP) of signals that differentiated the responder status of metabolic profiles. Pathway enrichment analysis was conducted in Metaboanalyst. Baseline data did not differ significantly. Weight loss was 7.2 ± 2.5 kg for the 22 responders, and 2.0 ± 2.0 kg for the 20 non-responders. Mummichog pathway enrichment analysis revealed that perturbations were most significant for caffeine and caffeine-related metabolism (p = 0.00028). Caffeine and related metabolites, which were all increased in responders, included 1,3,7-trimethylxanthine (VIP = 2.0, p = 0.033, fold change (FC) = 1.9), theophylline (VIP = 2.0, p = 0.024, FC = 1.8), paraxanthine (VIP = 2.0, p = 0.028, FC = 1.8), 1-methylxanthine (VIP = 1.9, p = 0.023, FC = 2.2), 5-acetylamino-6-amino-3-methyluracil (VIP = 2.2, p = 0.025, FC = 2.2), 1,3-dimethyl uric acid (VIP = 2.1, p = 0.023, FC = 2.3), and 1,7-dimethyl uric acid (VIP = 2.0, p = 0.035, FC = 2.2). Increased levels of phytochemicals and microbiome-related metabolites were also found in responders compared to non-responders. In this pilot weight loss intervention, older adults with obesity and evidence of significant enrichment for caffeine metabolism were more likely to achieve ≥5% weight loss. Further studies are needed to examine these associations in prospective cohorts and larger randomized trials.

16.
JMIR Aging ; 5(3): e33845, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35947445

RESUMO

BACKGROUND: Older adults who engage in physical activity can reduce their risk of mobility impairment and disability. Short amounts of walking can improve quality of life, physical function, and cardiovascular health. Various programs have been implemented to encourage older adults to engage in physical activity, but sustaining their motivation continues to be a challenge. Ubiquitous devices, such as mobile phones and smartwatches, coupled with machine-learning algorithms, can potentially encourage older adults to be more physically active. Current algorithms that are deployed in consumer devices (eg, Fitbit) are proprietary, often are not tailored to the movements of older adults, and have been shown to be inaccurate in clinical settings. Step-counting algorithms have been developed for smartwatches, but only using data from younger adults and, often, were only validated in controlled laboratory settings. OBJECTIVE: We sought to develop and validate a smartwatch step-counting app for older adults and evaluate the algorithm in free-living settings over a long period of time. METHODS: We developed and evaluated a step-counting app for older adults on an open-source wrist-worn device (Amulet). The app includes algorithms to infer the level of physical activity and to count steps. We validated the step-counting algorithm in the lab (counting steps from a video recording, n=20) and in free-living conditions-one 2-day field study (n=6) and two 12-week field studies (using the Fitbit as ground truth, n=16). During app system development, we evaluated 4 walking patterns: normal, fast, up and down a staircase, and intermittent speed. For the field studies, we evaluated 5 different cut-off values for the algorithm, using correlation and error rate as the evaluation metrics. RESULTS: The step-counting algorithm performed well. In the lab study, for normal walking (R2=0.5), there was a stronger correlation between the Amulet steps and the video-validated steps; for all activities, the Amulet's count was on average 3.2 (2.1%) steps lower (SD 25.9) than the video-validated count. For the 2-day field study, the best parameter settings led to an association between Amulet and Fitbit (R2=0.989) and 3.1% (SD 25.1) steps lower than Fitbit, respectively. For the 12-week field study, the best parameter setting led to an R2 value of 0.669. CONCLUSIONS: Our findings demonstrate the importance of an iterative process in algorithm development before field-based deployment. This work highlights various challenges and insights involved in developing and validating monitoring systems in real-world settings. Nonetheless, our step-counting app for older adults had good performance relative to the ground truth (a commercial Fitbit step counter). Our app could potentially be used to help improve physical activity among older adults.

17.
J Nutr Gerontol Geriatr ; 41(2): 126-139, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35502533

RESUMO

It is unclear which energy expenditure prediction equation should guide weight loss interventions in older adults with obesity. We ascertained the validity of four equations commonly used in practice in a series of weight loss studies of adults aged ≥65 with a body mass index ≥30kg/m2 using indirect calorimetry data. Diagnostic accuracy was defined as <10% discrepancy between predicted and measured resting metabolic rate (RMR). Mean was 73.4 years. RMR using the ReeVue was 1,643 kCal. With 59.0% accuracy, the WHO equation demonstrated the highest accuracy while the Harris-Benedict yielded 53.5% accuracy. The Owens equation demonstrated the least variability (21.5% overprediction, 27.8% underprediction) with 50.7% accuracy. A SECA bioimpedance analyzer noted the second lowest accuracy of 49.6%. Only 43.1% of measurements were within 10% of the gold-standard indirect calorimetry value using the Mifflin equation. All equations demonstrated <60% accuracy suggesting a great need for estimating energy needs.


Assuntos
Metabolismo Basal , Obesidade , Idoso , Índice de Massa Corporal , Metabolismo Energético , Humanos , Obesidade/metabolismo , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Redução de Peso
18.
J Am Geriatr Soc ; 70(5): 1442-1449, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35113453

RESUMO

BACKGROUND: Declining mortality rates and an aging population have contributed to increasing rates of multimorbidity (MM) in the United States. MM is strongly associated with a decline in physical function. Obesity is an important risk factor for the development of MM, and its prevalence continues to rise. Our study aimed to evaluate the associations between obesity, MM, and rates of functional limitations in older adults. METHODS: We analyzed body mass index (BMI) and self-reported comorbidity data from 7261 individuals aged ≥60 years from the National Health and Nutrition Examination Surveys 2005-2014. Weight status was defined based on standard BMI categories. MM was defined as 2 or more comorbidities, while functional limitations were self-reported. Adjusted logistic regression quantified the association between standard BMI categories and MM. We also examined the difference in the prevalence of limitations between those with and without MM. RESULTS: The overall proportion of individuals with concomitant MM and obesity was 27.0%. Compared to a normal BMI, older adults with obesity had higher odds of MM (Prevalence odds ratio 1.79, 95% CI 1.49, 2.12). Overall, 67.5% of patients with MM also reported a functional limitation, with rates of functional limitation increasing with increasing BMI. When evaluating functional limitations in those with MM by BMI class, 90% of patients classified as severely obese (BMI ≥40 kg/m2 ) with MM also had a concomitant functional limitation. CONCLUSIONS: Compared to normal weight status, obesity is associated with an increased burden of MM and functional limitation among older adults. Our results underscore the importance of identifying and addressing obesity, MM, and functional limitation patterns and the need for evidence-based interventions that address all three conditions in this population.


Assuntos
Multimorbidade , Obesidade , Idoso , Envelhecimento , Índice de Massa Corporal , Comorbidade , Humanos , Obesidade/epidemiologia , Estados Unidos/epidemiologia
19.
Clin Nutr ; 41(9): 1861-1873, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35939904

RESUMO

BACKGROUND: Aging alters biological processes resulting in body fat redistribution, loss of lean muscle mass, and reduced muscle strength, termed sarcopenia. Nutrition is an important modifiable risk factor in the development of sarcopenia. Food insecurity refers to limited or uncertain access to enough food for an active, healthy life, and is prevalent among older adults. The objective of this study was to examine the relationship between food insecurity and probable sarcopenia in older adults. METHODS: We examined 3632 adults ≥60 years old from the 2011-2014 National Health and Nutrition Examination Surveys (NHANES). For our analysis food insecurity was identified using the Food Security Survey Module (FSSM). The primary outcome was based on the Sarcopenia Definitions and Outcomes consortium (SDOC) definition. Secondary outcomes were based on three other different grip strength cut-offs as there is debate within the field as to the optimal definition of sarcopenia. Consistent with the revised European consensus on the definition and diagnosis of Sarcopenia (EWGSOP2) recommendations, we used the term probable sarcopenia throughout this text as definitions were based on muscle strength alone and did not include an evaluation of muscle quality. Sensitivity analyses were performed using the standard four category definition of food security. We used logistic regression to examine the association between food insecurity and sarcopenia. RESULTS: Using the Sarcopenia Definitions and Outcomes Consortium definition, 24.7% were classified as having probable sarcopenia (low grip strength); 5.5% had food insecurity and food insecurity was associated with probable sarcopenia (OR 1.51, 95%CI 1.03-2.22). Using three other definitions of probable sarcopenia, food insecurity was significantly associated with probable sarcopenia using the Foundation for the National Institute of Health definition using grip strength alone (OR 1.71, 95%CI 1.08-2.71), but food insecurity was not associated with food insecurity using definitions related to grip strength/BMI (OR 1.16, 95%CI 0.76-1.78) or grip strength/weight (OR 1.14, 95%CI 0.85-1.54). CONCLUSIONS: In this nationally representative cohort study, individuals classified as having food insecurity were more likely to have probable sarcopenia (low grip strength) compared to those with full food security. Future studies should examine whether food insecurity interventions may reduce probable sarcopenia and associated adverse outcomes.


Assuntos
Sarcopenia , Idoso , Estudos de Coortes , Força da Mão/fisiologia , Humanos , Pessoa de Meia-Idade , Força Muscular/fisiologia , Inquéritos Nutricionais , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia
20.
Clin Epigenetics ; 13(1): 46, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33653394

RESUMO

BACKGROUND: Assessing functional ability is an important component of understanding healthy aging. Objective measures of functional ability include grip strength, gait speed, sit-to-stand time, and 6-min walk distance. Using samples from a weight loss clinical trial in older adults with obesity, we examined the association between changes in physical function and DNA-methylation-based biological age at baseline and 12 weeks in 16 individuals. Peripheral blood DNA methylation was measured (pre/post) with the Illumina HumanMethylationEPIC array and the Hannum, Horvath, and PhenoAge DNA methylation age clocks were used. Linear regression models adjusted for chronological age and sex tested the relationship between DNA methylation age and grip strength, gait speed, sit-to-stand, and 6-min walk. RESULTS: Participant mean weight loss was 4.6 kg, and DNA methylation age decreased 0.8, 1.1, and 0.5 years using the Hannum, Horvath, and PhenoAge DNA methylation clocks respectively. Mean grip strength increased 3.2 kg. Decreased Hannum methylation age was significantly associated with increased grip strength (ß = -0.30, p = 0.04), and increased gait speed (ß = 0.02, p = 0.05), in adjusted models. Similarly, decreased methylation age using the PhenoAge clock was associated with significantly increased gait speed (ß = 0.02, p = 0.04). A decrease in Horvath DNA methylation age and increase in physical functional ability did not demonstrate a significant association. CONCLUSIONS: The observed relationship between increased physical functional ability and decreased biological age using DNA methylation clocks demonstrate the potential utility of DNA methylation clocks to assess interventional approaches to improve health in older obese adults. TRIAL REGISTRATION: National Institute on Aging (NIA), NCT03104192. Posted April 7, 2017, https://clinicaltrials.gov/ct2/show/NCT03104192.


Assuntos
Envelhecimento/genética , Manutenção do Peso Corporal/genética , Envelhecimento Saudável/genética , Obesidade/genética , Idoso , Ilhas de CpG , Metilação de DNA , Epigenômica , Feminino , Força da Mão/fisiologia , Humanos , Modelos Lineares , Masculino , Obesidade/sangue , Desempenho Físico Funcional , Velocidade de Caminhada/genética , Velocidade de Caminhada/fisiologia , Redução de Peso/genética
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