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1.
CA Cancer J Clin ; 69(6): 468-484, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31617590

RESUMEN

Multiple organizations around the world have issued evidence-based exercise guidance for patients with cancer and cancer survivors. Recently, the American College of Sports Medicine has updated its exercise guidance for cancer prevention as well as for the prevention and treatment of a variety of cancer health-related outcomes (eg, fatigue, anxiety, depression, function, and quality of life). Despite these guidelines, the majority of people living with and beyond cancer are not regularly physically active. Among the reasons for this is a lack of clarity on the part of those who work in oncology clinical settings of their role in assessing, advising, and referring patients to exercise. The authors propose using the American College of Sports Medicine's Exercise Is Medicine initiative to address this practice gap. The simple proposal is for clinicians to assess, advise, and refer patients to either home-based or community-based exercise or for further evaluation and intervention in outpatient rehabilitation. To do this will require care coordination with appropriate professionals as well as change in the behaviors of clinicians, patients, and those who deliver the rehabilitation and exercise programming. Behavior change is one of many challenges to enacting the proposed practice changes. Other implementation challenges include capacity for triage and referral, the need for a program registry, costs and compensation, and workforce development. In conclusion, there is a call to action for key stakeholders to create the infrastructure and cultural adaptations needed so that all people living with and beyond cancer can be as active as is possible for them.


Asunto(s)
Terapia por Ejercicio/métodos , Oncología Médica/métodos , Neoplasias/prevención & control , Neoplasias/rehabilitación , Servicios de Salud Comunitaria/métodos , Servicios de Salud Comunitaria/normas , Prestación Integrada de Atención de Salud/métodos , Prestación Integrada de Atención de Salud/normas , Terapia por Ejercicio/normas , Humanos , Oncología Médica/normas , Neoplasias/complicaciones , Neoplasias/psicología , Guías de Práctica Clínica como Asunto
2.
Pain Med ; 24(Suppl 1): S95-S104, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-36721327

RESUMEN

OBJECTIVE: One aim of the Back Pain Consortium (BACPAC) Research Program is to develop an integrated model of chronic low back pain that is informed by combined data from translational research and clinical trials. We describe efforts to maximize data harmonization and accessibility to facilitate Consortium-wide analyses. METHODS: Consortium-wide working groups established harmonized data elements to be collected in all studies and developed standards for tabular and nontabular data (eg, imaging and omics). The BACPAC Data Portal was developed to facilitate research collaboration across the Consortium. RESULTS: Clinical experts developed the BACPAC Minimum Dataset with required domains and outcome measures to be collected by use of questionnaires across projects. Other nonrequired domain-specific measures are collected by multiple studies. To optimize cross-study analyses, a modified data standard was developed on the basis of the Clinical Data Interchange Standards Consortium Study Data Tabulation Model to harmonize data structures and facilitate integration of baseline characteristics, participant-reported outcomes, chronic low back pain treatments, clinical exam, functional performance, psychosocial characteristics, quantitative sensory testing, imaging, and biomechanical data. Standards to accommodate the unique features of chronic low back pain data were adopted. Research units submit standardized study data to the BACPAC Data Portal, developed as a secure cloud-based central data repository and computing infrastructure for researchers to access and conduct analyses on data collected by or acquired for BACPAC. CONCLUSIONS: BACPAC harmonization efforts and data standards serve as an innovative model for data integration that could be used as a framework for other consortia with multiple, decentralized research programs.


Asunto(s)
Dolor de la Región Lumbar , Humanos , Dolor de la Región Lumbar/terapia , Evaluación de Resultado en la Atención de Salud , Proyectos de Investigación
3.
Pain Med ; 24(Suppl 1): S3-S12, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-36622041

RESUMEN

In 2019, the National Health Interview survey found that nearly 59% of adults reported pain some, most, or every day in the past 3 months, with 39% reporting back pain, making back pain the most prevalent source of pain, and a significant issue among adults. Often, identifying a direct, treatable cause for back pain is challenging, especially as it is often attributed to complex, multifaceted issues involving biological, psychological, and social components. Due to the difficulty in treating the true cause of chronic low back pain (cLBP), an over-reliance on opioid pain medications among cLBP patients has developed, which is associated with increased prevalence of opioid use disorder and increased risk of death. To combat the rise of opioid-related deaths, the National Institutes of Health (NIH) initiated the Helping to End Addiction Long-TermSM (HEAL) initiative, whose goal is to address the causes and treatment of opioid use disorder while also seeking to better understand, diagnose, and treat chronic pain. The NIH Back Pain Consortium (BACPAC) Research Program, a network of 14 funded entities, was launched as a part of the HEAL initiative to help address limitations surrounding the diagnosis and treatment of cLBP. This paper provides an overview of the BACPAC research program's goals and overall structure, and describes the harmonization efforts across the consortium, define its research agenda, and develop a collaborative project which utilizes the strengths of the network. The purpose of this paper is to serve as a blueprint for other consortia tasked with the advancement of pain related science.


Asunto(s)
Dolor Crónico , Dolor de la Región Lumbar , Trastornos Relacionados con Opioides , Adulto , Humanos , Proyectos de Investigación , Analgésicos Opioides/uso terapéutico , Comités Consultivos , Dimensión del Dolor/métodos , Dolor Crónico/epidemiología , Dolor de la Región Lumbar/diagnóstico , Dolor de la Región Lumbar/terapia , Trastornos Relacionados con Opioides/epidemiología , Trastornos Relacionados con Opioides/terapia
4.
N Engl J Med ; 379(13): 1205-1215, 2018 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-30280654

RESUMEN

BACKGROUND: Despite the high rate of sudden death after myocardial infarction among patients with a low ejection fraction, implantable cardioverter-defibrillators are contraindicated until 40 to 90 days after myocardial infarction. Whether a wearable cardioverter-defibrillator would reduce the incidence of sudden death during this high-risk period is unclear. METHODS: We randomly assigned (in a 2:1 ratio) patients with acute myocardial infarction and an ejection fraction of 35% or less to receive a wearable cardioverter-defibrillator plus guideline-directed therapy (the device group) or to receive only guideline-directed therapy (the control group). The primary outcome was the composite of sudden death or death from ventricular tachyarrhythmia at 90 days (arrhythmic death). Secondary outcomes included death from any cause and nonarrhythmic death. RESULTS: Of 2302 participants, 1524 were randomly assigned to the device group and 778 to the control group. Participants in the device group wore the device for a median of 18.0 hours per day (interquartile range, 3.8 to 22.7). Arrhythmic death occurred in 1.6% of the participants in the device group and in 2.4% of those in the control group (relative risk, 0.67; 95% confidence interval [CI], 0.37 to 1.21; P=0.18). Death from any cause occurred in 3.1% of the participants in the device group and in 4.9% of those in the control group (relative risk, 0.64; 95% CI, 0.43 to 0.98; uncorrected P=0.04), and nonarrhythmic death in 1.4% and 2.2%, respectively (relative risk, 0.63; 95% CI, 0.33 to 1.19; uncorrected P=0.15). Of the 48 participants in the device group who died, 12 were wearing the device at the time of death. A total of 20 participants in the device group (1.3%) received an appropriate shock, and 9 (0.6%) received an inappropriate shock. CONCLUSIONS: Among patients with a recent myocardial infarction and an ejection fraction of 35% or less, the wearable cardioverter-defibrillator did not lead to a significantly lower rate of the primary outcome of arrhythmic death than control. (Funded by the National Institutes of Health and Zoll Medical; VEST ClinicalTrials.gov number, NCT01446965 .).


Asunto(s)
Muerte Súbita Cardíaca/prevención & control , Desfibriladores , Infarto del Miocardio/terapia , Taquicardia Ventricular/prevención & control , Dispositivos Electrónicos Vestibles , Anciano , Muerte Súbita Cardíaca/etiología , Desfibriladores/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Infarto del Miocardio/mortalidad , Volumen Sistólico , Taquicardia Ventricular/mortalidad , Resultado del Tratamiento , Dispositivos Electrónicos Vestibles/efectos adversos
5.
J Cardiovasc Electrophysiol ; 31(5): 1009-1018, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32083365

RESUMEN

BACKGROUND: Vest Prevention of Early Sudden Death Trial did not demonstrate a significant reduction in arrhythmic death with the wearable cardioverter-defibrillator (WCD), but compliance with the device may have substantially affected the results. ThePletcher influence of WCD compliance on outcomes has not yet been fully evaluated. METHODS: Using linear and pooled logistic models, we performed as-treated analyses omitting person-time in the hospital and adjusted for correlates of WCD compliance. To assess the impact of early stopping of WCD, we performed a per-protocol Kaplan-Meier analysis, censoring after the last day the WCD was worn. Interactions of potential effect modifiers with treatment assignment and WCD compliance on outcomes were investigated. Finally, we used linear models to identify predictors of WCD compliance. RESULTS: A per-protocol analysis demonstrated a significant reduction in total (P < .001) and arrhythmic (P = .001) mortality. Better WCD compliance was independently predicted by cardiac arrest during index myocardial infarction (MI), higher Cr, diabetes, prior heart failure, EF ≤ 25%, Polish enrolling center and number of WCD alarms, while worse compliance was predicted by being divorced, Asian race, higher body mass index, prior percutaneous coronary intervention, or any WCD shock. Neither excluding time in hospital from the as-treated analysis nor adjustment for factors affecting WCD compliance materially changed the results. No variable demonstrated a significant interaction in either the intention-to-treat or as-treated analysis. CONCLUSION: Robust sensitivity analyses of as-treated and per-protocol analyses suggest that the WCD is protective in compliant patients with ejection fraction less than or equal to 35% during the first 3 months post-MI.


Asunto(s)
Arritmias Cardíacas/terapia , Muerte Súbita Cardíaca/prevención & control , Desfibriladores , Cardioversión Eléctrica/instrumentación , Infarto del Miocardio/terapia , Cooperación del Paciente , Dispositivos Electrónicos Vestibles , Anciano , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiología , Arritmias Cardíacas/mortalidad , Muerte Súbita Cardíaca/etiología , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/mortalidad , Factores Protectores , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
6.
Magn Reson Med ; 79(3): 1722-1729, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28714169

RESUMEN

PURPOSE: To develop a novel technique for reliable quantification of bone marrow fat content and composition using in vivo MR spectroscopy (MRS). METHODS: An MRS quantification method combining both advantages of Voigt line shape model and time-domain analysis was developed. The proposed method was tested using computer-simulated data and in vivo data acquired at lumbar vertebral bodies of 23 subjects (age, 83.8 ± 3.7 y; male, n = 13; female, n = 10) from L1 to L4. Reliability and reproducibility were calculated for the quantification results. Comparisons between the proposed method and some conventional methods were conducted. RESULTS: Low mean absolute percentage errors and low mean coefficients of variation for computer simulations suggest that the proposed method is accurate and precise. By using this method, marrow fat content can be quantified reliably, even for data with low spectral resolution and low signal-to-noise ratio (SNR). Unsaturation level can be reliably quantified for data with moderate spectral resolution and moderate SNR. Results obtained from in vivo data using the proposed method demonstrated better model fit than conventional methods. CONCLUSION: The method proposed in this study has better performance than conventional methods in the quantification of bone marrow MRS data and has great potential for wide applications of studying marrow fat content and composition. Magn Reson Med 79:1722-1729, 2018. © 2017 International Society for Magnetic Resonance in Medicine.


Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Médula Ósea/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Tejido Adiposo/fisiología , Anciano de 80 o más Años , Médula Ósea/fisiología , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados
7.
Carcinogenesis ; 35(2): 346-55, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24213602

RESUMEN

Although elevated circulating estrogens are associated with increased postmenopausal breast cancer risk, less is known regarding the role of estrogen metabolism in breast carcinogenesis. We conducted a case-cohort study within the Breast and Bone Follow-up to the Fracture Intervention Trial to assess serum estrogens and estrogen metabolites (EMs) in 407 incident breast cancer cases diagnosed during follow-up and a subcohort of 496 women. In 1992-93, women completed a baseline questionnaire and provided blood samples. Hazard ratios (HRs) and 95% confidence intervals (CIs), adjusted for geography and trial participation status, were estimated using Cox proportional hazard regression. Serum concentrations of EMs were measured by liquid chromatography-tandem mass spectrometry. EMs (quintiles, Q) were analyzed individually, as metabolic pathways (C-2, -4 or -16) and as ratios. Elevated circulating estradiol was associated with increased breast cancer risk (HRQ5vsQ1 = 1.86; 95% CI: 1.19-2.90; P trend = 0.04). An elevated ratio of the 2-hydroxylation pathway (HRQ5vsQ1 = 0.69; 95% CI: 0.46-1.05; P trend = 0.01) and 4-hydroxylation pathway (HRQ5vsQ1 = 0.61; 95% CI: 0.40-0.93; P trend = 0.004) to parent estrogens (estradiol and estrone) was inversely associated with risk. A higher ratio of the 2/16-hydroxylation pathways was associated with reduced risk (HRQ5vsQ1 = 0.60; 95% CI: 0.40-0.90; P trend = 0.002). Increased 2- or 4-hydroxylation of parent estrogens may lower risk of postmenopausal breast cancer. Analyses of metabolic pathways may help elucidate the role of estrogen metabolism in breast carcinogenesis.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias de la Mama/diagnóstico , Estrógenos/metabolismo , Anciano , Anciano de 80 o más Años , Densidad Ósea , Neoplasias de la Mama/sangre , Neoplasias de la Mama/etiología , Estudios de Casos y Controles , Cromatografía Liquida , Estrona/sangre , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Posmenopausia , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Espectrometría de Masas en Tándem
8.
J Back Musculoskelet Rehabil ; 37(4): 909-920, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38427463

RESUMEN

BACKGROUND: Tools, such as the STarTBack Screening Tool (SBT), have been developed to identify risks of progressing to chronic disability in low back pain (LBP) patients in the primary care population. However, less is known about predictors of change in function after treatment in the specialty care population. OBJECTIVE: We pursued a retrospective observational cohort study involving LBP patients seen in a multidisciplinary specialty clinic to assess which features can predict change in function at follow-up. METHODS: The SBT was administered at initial visit, and a variety of patient characteristics were available in the chart including the presence of chronic overlapping pain conditions (COPCs). Patient Reported Outcomes Measurement Information System-10 (PROMIS-10) global physical health (PH) and global mental health (MH) were measured at baseline and at pragmatic time points during follow-up. Linear regression was used to estimate adjusted associations between available features and changes in PROMIS scores. RESULTS: 241 patients were followed for a mean of 17.0 ± 7.5 months. Mean baseline pain was 6.7 (SD 2.1), PROMIS-10 global MH score was 44.8 (SD 9.3), and PH score was 39.4 (SD 8.6). 29.7% were low-risk on the SBT, 41.8% were medium-risk, and 28.5% were high-risk. Mean change in MH and PH scores from baseline to the follow-up questionnaire were 0.86 (SD 8.11) and 2.39 (SD 7.52), respectively. Compared to low-risk patients, high-risk patients had a mean 4.35 points greater improvement in their MH score (p= 0.004) and a mean 3.54 points greater improvement in PH score (p= 0.006). Fewer COPCs also predicted greater improvement in MH and PH. CONCLUSIONS: SBT and the presence of COPC, which can be assessed at initial presentation to a specialty clinic, can predict change in PROMIS following treatment. Effort is needed to identify other factors that can help predict change in function after treatment in the specialty care setting.


Asunto(s)
Dolor Crónico , Dolor de la Región Lumbar , Medición de Resultados Informados por el Paciente , Humanos , Dolor de la Región Lumbar/terapia , Dolor de la Región Lumbar/fisiopatología , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Dolor Crónico/terapia , Adulto , Dimensión del Dolor , Evaluación de la Discapacidad
9.
medRxiv ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39399002

RESUMEN

Background Context: There are a number of risk factors- from biological, psychological, and social domains- for non-specific chronic low back pain (cLBP). Many cLBP treatments target risk factors on the assumption that the targeted factor is not just associated with cLBP but is also a cause (i.e, a causal risk factor). In most cases this is a strong assumption, primarily due to the possibility of confounding variables. False assumptions about the causal relationships between risk factors and cLBP likely contribute to the generally marginal results from cLBP treatments. Purpose: The objectives of this study were to a) using rigorous confounding control compare associations between modifiable causal risk factors identified by Mendelian randomization (MR) studies with associations in a cLBP population and b) estimate the association of these risk factors with cLBP outcomes. Study Design/Setting: Cross sectional analysis of a longitudinal, online, observational study. Patient Sample: 1,376 participants in BACKHOME, a longitudinal observational e-Cohort of U.S. adults with cLBP that is part of the NIH Back Pain Consortium (BACPAC) Research Program. Outcome Measures: Pain, Enjoyment of Life, and General Activity (PEG) Scale. Methods: Five risk factors were selected based on evidence from MR randomization studies: sleep disturbance, depression, BMI, alcohol use, and smoking status. Confounders were identified using the ESC-DAG approach, a rigorous method for building directed acyclic graphs based on causal criteria. Strong evidence for confounding was found for age, female sex, education, relationship status, financial strain, anxiety, fear avoidance and catastrophizing. These variables were used to determine the adjustment sets for the primary analysis. Potential confounders with weaker evidence were used for a sensitivity analysis. Results: Participants had the following characteristics: age 54.9 ± 14.4 years, 67.4% female, 60% never smokers, 29.9% overweight, 39.5% obese, PROMIS sleep disturbance T-score 54.8 ± 8.0, PROMIS depression T-score 52.6 ± 10.1, Fear-avoidance Beliefs Questionnaire 11.6 ± 5.9, Patient Catastrophizing Scale 4.5 ± 2.6, PEG 4.4 ± 2.2. In the adjusted models alcohol use, sleep disturbance, depression, and obesity were associated with PEG, after adjusting for confounding variables identified via a DAG constructed using a rigorous protocol. The adjusted effect estimates- the expected change in the PEG outcome for every standard deviation increase or decrease in the exposure (or category shift for categorical exposures) were the largest for sleep disturbance and obesity. Each SD increase in the PROMIS sleep disturbance T-score resulted in a mean 0.77 (95% CI: 0.66, 0.88) point increase in baseline PEG score. Compared to participants with normal BMI, adjusted mean PEG score was slightly higher by 0.37 points (95% CI: 0.09, 0.65) for overweight participants, about 0.8 to 0.9 points higher for those in obesity classes I and II, and 1.39 (95% CI: 0.98, 1.80) points higher for the most obese participants. Each SD increase in the PROMIS depression T-score was associated with a mean 0.28 (95% CI: 0.17, 0.40) point increase in baseline PEG score, while each SD decrease in number of alcoholic drinks per week resulted in a mean 0.12 (95%CI: 0.01, 0.23) increase in baseline PEG score in the adjusted model. Conclusions: Several modifiable causal risk factors for cLBP - alcohol use, sleep disturbance, depression, and obesity- are associated with PEG, after adjusting for confounding variables identified via a DAG constructed using a rigorous protocol. Convergence of our findings for sleep disturbance, depression, and obesity with the results from MR studies, which have different designs and biases, strengthens the evidence for causal relationships between these risk factors and cLBP (1). The estimated effect of change in a risk factors on change in PEG were the largest for sleep disturbance and obesity. Future analyses will evaluate these relationships with longitudinal data.

10.
Artículo en Inglés | MEDLINE | ID: mdl-39394788

RESUMEN

CONTEXT: Higher levels of FSH are associated with bone loss among women during the perimenopausal transition and among older men, independent of estradiol and testosterone levels, but whether higher FSH is an independent fracture risk factor is unknown. OBJECTIVE: Determine whether baseline FSH level predicts subsequent hip fracture in older adults. SETTING, DESIGN, PARTICIPANTS: Using a case-cohort design, we randomly sampled 295 participants stratified by sex from the Age, Gene/Environment Susceptibility (AGES)-Reykjavik cohort, including 25 participants with incident hip fracture within 10 years after baseline. We sampled an additional 230 sex-stratified participants with incident hip fracture. Serum FSH and sex hormone levels were measured at baseline. Robust weighted Cox proportional hazards models were used to determine the relationship between FSH and hip fracture risk. MAIN OUTCOME: Incident hip fracture. RESULTS: As no interaction was identified between FSH and sex for the relationship with fracture, men and women were pooled for analysis. Higher levels of FSH were associated with a significantly increased risk of incident hip fracture in models adjusted for age and sex [hazard ratio (HR) 1.24 (95% CI 1.04-1.48, p=0.02)] and after further adjustment for estradiol, testosterone, and sex hormone binding globulin levels [HR 1.20 (95% CI 1.01-1.44, p=0.04) per sex-specific SD increase in FSH level]. CONCLUSIONS: Higher FSH is associated with increased risk of subsequent hip fracture. Our findings support a growing body of evidence for direct pleiotropic effects of FSH on bone, and for a role for FSH in aging and disability independent of sex hormone levels.

11.
medRxiv ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38645207

RESUMEN

Objective: The University of California, San Francisco (UCSF) Core Center for Patient-centric, Mechanistic Phenotyping in Chronic Low Back Pain (REACH) is one of the three NIH Back Pain Consortium (BACPAC) Research Programs Mechanistic Research Centers (MRCs). The goal of UCSF REACH is to define cLBP phenotypes and pain mechanisms that can lead to effective, personalized treatments for patients across the population. The primary objective of this research project is to address the critical need for new diagnostic and prognostic markers, and associated patient classification protocols for chronic low back pain (cLBP) treatment. Design: To meet this objective, REACH is conducting two large investigator-initiated translational research cohort studies called: The Longitudinal Clinical Cohort for Comprehensive Deep Phenotyping of Chronic Low-Back Pain (cLBP) Adults Study (comeBACK) and the Chronic Low-Back Pain (cLBP) in Adults Study (BACKHOME). Setting: comeBACK is a longitudinal multicenter in-person observational study of 450 adults with chronic low back pain designed to perform comprehensive deep phenotyping. While, the BACKHOME study is a site-less longitudinal observational e-cohort of approximately 3000 U.S. adults with cLBP. To our knowledge, BACKHOME is the largest prospective remote registry of nationwide adults with cLBP. Methods: Both the comeBACK and BACKHOME studies are collecting a robust and comprehensive set of risk factors, outcomes, and covariates in order to perform deep phenotyping of cLBP patients based on combined biopsychosocial variables to: define cLBP subtypes, establish phenotyping tools for routine clinical evaluation, and lead to improved cLBP outcomes in the future. The data from both studies will be used to establish techniques to develop a patient-centric definition of treatment success and to analyze cLBP patient traits to define clinically useful cLBP phenotypes, using a combination of traditional data analyses and deep learning methods. Conclusions: These 2 pivotal studies, in conjunction with the ancillary studies being performed in both comeBACK and BACKHOME, and the other BACPAC-consortium research projects, we will be able to address a number of diagnostic and therapeutic issues in this complex and diverse patient population with cLBP. These studies will help clarify biopsychosocial mechanisms of cLBP with the aim to provide a foundation to improve the evaluation of treatment effectiveness and to spur new avenues of therapeutic research, including personalized outcome measures that constitute a clinically meaningful treatment effect for individual cLBP patients.

12.
Calcif Tissue Int ; 92(5): 477-86, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23377193

RESUMEN

Factors that contribute to bone fragility in type 2 diabetes are not well understood. We assessed the effects of intensive glycemic control, thiazolidinediones (TZDs), and A1C levels on bone geometry and strength at the radius and tibia. In a substudy of the Action to Control Cardiovascular Risk in Diabetes trial, peripheral quantitative computed tomographic (pQCT) scans of the radius and tibia were obtained 2 years after randomization on 73 participants (intensive n = 35, standard n = 38). TZD use and A1C levels were measured every 4 months during the trial. Effects of intervention assignment, TZD use, and A1C on pQCT parameters were assessed in linear regression models. Intensive, compared with standard, glycemic control was associated with 1.3 % lower cortical volumetric BMD at the tibia in men (p = 0.02) but not with other pQCT parameters. In women, but not men, each additional year of TZD use was associated with an 11 % lower polar strength strain index (SSIp) at the radius (p = 0.04) and tibia (p = 0.002) in models adjusted for A1C levels. In women, each additional 1 % increase in A1C was associated with an 18 % lower SSIp at the ultradistal radius (p = 0.04) in models adjusted for TZD use. There was no consistent evidence of an effect of intensive, compared with standard, glycemic control on bone strength at the radius or tibia. In women, TZD use may reduce bone strength at these sites. Higher A1C may also be associated with lower bone strength at the radius, but not tibia, in women.


Asunto(s)
Glucemia/metabolismo , Huesos/efectos de los fármacos , Diabetes Mellitus/tratamiento farmacológico , Radio (Anatomía)/efectos de los fármacos , Tiazolidinedionas/uso terapéutico , Tibia/efectos de los fármacos , Adulto , Anciano , Densidad Ósea , Huesos/patología , Complicaciones de la Diabetes/metabolismo , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X
13.
Am J Cardiol ; 187: 18-25, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36459743

RESUMEN

The VEST (Vest Prevention of Early Sudden Death Trial) showed a trend toward decreased sudden death and lower overall mortality with a wearable cardioverter-defibrillator (WCD) in the postmyocardial infarction (post-MI) period. However, it is unclear which patients should receive WCD therapy. We aimed to identify the risk factors for arrhythmic death, all-cause mortality, and ventricular tachyarrhythmias requiring appropriate shock to identify patients most likely to benefit from a WCD. The VEST trial included patients with acute MI with ejection fraction ≤35%. Using logistic regression, 7 risk factors were evaluated for association with arrhythmic death, all-cause mortality, and appropriate shock. Among 2,302 participants, 44 had arrhythmic death (1.9%) and 86 died of any cause (3.7%). Among 1,524 participants randomized to WCD, 20 experienced appropriate shock (1.3%) over 90 days. In the multivariable analyses, lower systolic blood pressure (SBP; odds ratio [OR] 1.64 per 10 mm Hg) and higher heart rate at discharge (OR 1.19 per 10 beats/min) were associated with arrhythmic death. Lower SBP (OR 1.37) and higher heart rate (OR 1.10) were associated with all-cause mortality. Higher heart rate (OR 1.20) was associated with appropriate shock. Patients with both SBP ≤100 and heart rate ≥100 were at increased odds of arrhythmic death (OR 4.82), all-cause mortality (OR 3.10), and appropriate shock (OR 6.13). In patients with acute MI and reduced ejection fraction, lower SBP and higher heart rate at discharge were strongly associated with arrhythmic death and all-cause mortality. In conclusion, these risk factors identify a select group at high risk of adverse events in a setting where WCD therapy is reasonable.


Asunto(s)
Desfibriladores Implantables , Infarto del Miocardio , Taquicardia Ventricular , Humanos , Desfibriladores Implantables/efectos adversos , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/etiología , Muerte Súbita Cardíaca/prevención & control , Taquicardia Ventricular/epidemiología , Taquicardia Ventricular/terapia , Taquicardia Ventricular/complicaciones , Cardioversión Eléctrica/efectos adversos , Infarto del Miocardio/complicaciones , Factores de Riesgo
14.
J Bone Miner Res ; 37(4): 700-710, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35038186

RESUMEN

Greater bone marrow adiposity (BMAT) is associated with lower bone mineral density (BMD) and vertebral fractures; less is known about BMAT composition and bone. We studied BMAT composition and bone outcomes in 465 participants from the Age Gene/Environment Susceptibility (AGES)-Reykjavik study. BMAT saturation and unsaturation, measured with magnetic resonance spectroscopy, were defined as the ratio of saturated (1.3 ppm peak) or unsaturated (5.3 ppm peak) lipid to total marrow contents, respectively. At baseline and follow-up visits, spine and hip BMD were assessed with quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA) and vertebral fractures were identified with DXA. Incident clinical fractures were identified through medical records for up to 8.8 years of follow-up. Associations between BMAT composition and BMD, bone loss, and fractures were evaluated in adjusted regression models. At baseline, mean ± standard deviation (SD) participant age was 81.7 ± 4.3 years, mean BMAT unsaturation was 3.5% ± 1.0%, and mean saturation was 46.3% ± 7.2% in the full cohort (47.7% women). Each SD increase in BMAT saturation was associated with lower trabecular BMD: -23.6% (spine) and -13.0% (total hip) (all p < 0.0001). Conversely, BMAT unsaturation (per SD increase) was associated with higher trabecular BMD: +17.5% (spine) and +11.5% (total hip) (all p < 0.001). BMAT saturation (per SD increase) was associated with greater risk for prevalent (odds ratio [OR] 1.46; 95% confidence interval [CI], 1.11-1.92) and incident (OR 1.55; 95% CI, 1.03-2.34) vertebral fracture. BMAT unsaturation (per SD increase) was associated with lower risk for incident vertebral fracture (OR 0.58; 95% CI, 0.38-0.89). In gender stratified analyses, BMAT saturation and unsaturation had opposite associations with incident clinical fracture among men. In general, saturated marrow lipids were associated with worse skeletal outcomes, whereas unsaturated lipids were associated with better outcomes. We recommend that future studies of marrow fat and skeletal health report measurements of saturated and unsaturated marrow lipids, rather than total marrow fat content alone. © 2022 American Society for Bone and Mineral Research (ASBMR).


Asunto(s)
Fracturas Óseas , Fracturas de la Columna Vertebral , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Densidad Ósea , Médula Ósea , Femenino , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/epidemiología , Humanos , Lípidos , Masculino , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología
15.
Cancer Epidemiol Biomarkers Prev ; 30(6): 1100-1105, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33827983

RESUMEN

BACKGROUND: The role of progestogens in colorectal cancer development is poorly characterized. To address this, our group developed a highly sensitive assay to measure concentrations of seven markers of endogenous progestogen metabolism among postmenopausal women. METHODS: The markers were measured in baseline serum collected from postmenopausal women in a case-cohort study within the breast and bone follow-up to the fracture intervention trial (B∼FIT). We followed women not using exogenous hormones at baseline (1992-1993) for up to 12 years: 187 women with incident colorectal cancer diagnosed during follow-up and a subcohort of 495 women selected on strata of age and clinical center. We used adjusted Cox regression models with robust variance to estimate risk for colorectal cancer [hazard ratios (HR), 95% confidence intervals (CI)]. RESULTS: High concentrations of pregnenolone and progesterone were not associated with colorectal cancer [quintile(Q)5 versus Q1: pregnenolone HR, 0.71, 95% CI, 0.40-1.25; progesterone HR, 1.25; 95% CI, 0.71-2.22]. A trend of increasing risk was suggested, but statistically imprecise across quintiles of 17-hydroxypregnenolone (Q2 to Q5 HRs, 0.75-1.44; P trend, 0.06). CONCLUSIONS: We used sensitive and reliable assays to measure multiple circulating markers of progestogen metabolism. Progestogens were generally unassociated with colorectal cancer risk in postmenopausal women. IMPACT: Our findings are consistent with most prior research on circulating endogenous sex hormones, which taken together suggest that sex hormones may not be major drivers of colorectal carcinogenesis in postmenopausal women.


Asunto(s)
Neoplasias Colorrectales/epidemiología , Posmenopausia/sangre , Progestinas/sangre , Anciano , Carcinogénesis/metabolismo , Estudios de Casos y Controles , Neoplasias Colorrectales/metabolismo , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Persona de Mediana Edad , Posmenopausia/metabolismo , Progestinas/metabolismo , Estudios Prospectivos , Factores de Riesgo
16.
J Clin Endocrinol Metab ; 106(10): 2876-2889, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34212197

RESUMEN

CONTEXT: FSH may have independent actions on bone remodeling and body fat regulation. Cross-sectionally, we have shown that serum FSH is associated with bone mineral density (BMD) and body fat in older postmenopausal women, but it remains unknown whether FSH predicts bone and fat changes. OBJECTIVE: We examined whether baseline FSH level is associated with subsequent bone loss or body composition changes in older adults. SETTING, DESIGN, PARTICIPANTS: We studied 162 women and 158 men (mean age 82 ± 4 years) from the Age, Gene/Environment Susceptibility (AGES)-Bone Marrow Adiposity cohort, a substudy of the AGES-Reykjavik Study of community-dwelling older adults. Skeletal health and body composition were characterized at baseline and 3 years later. MAIN OUTCOMES: Annualized change in BMD and body composition by dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT). Models were adjusted for serum estradiol and testosterone levels. RESULTS: There was no evidence for an association between baseline FSH level and change in BMD or body composition by DXA or QCT. For femoral neck areal BMD, adjusted mean difference (95% CI) per SD increase in FSH was 1.3 (-0.7 to 3.3) mg/cm2/y in women, and -0.2 (-2.6 to 2.2) mg/cm2/y in men. For visceral fat, adjusted mean difference (95% CI) per SD increase in FSH was 1.80 (-0.03 to 3.62) cm2/y in women, and -0.33 (-3.73 to 3.06) cm2/y in men. CONCLUSIONS: Although cross-sectional studies and studies in perimenopausal women have demonstrated associations between FSH and BMD and body composition, in older adults, FSH level is not associated with bone mass or body composition changes.


Asunto(s)
Tejido Adiposo/metabolismo , Composición Corporal , Densidad Ósea , Enfermedades Óseas Metabólicas/sangre , Hormona Folículo Estimulante/sangre , Absorciometría de Fotón , Anciano de 80 o más Años , Enfermedades Óseas Metabólicas/diagnóstico por imagen , Femenino , Cuello Femoral/diagnóstico por imagen , Humanos , Masculino
17.
Cancer Epidemiol Biomarkers Prev ; 30(11): 2030-2037, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34465588

RESUMEN

BACKGROUND: Postmenopausal pregnenolone and/or progesterone levels in relation to endometrial and ovarian cancer risks have been infrequently evaluated. To address this, we utilized a sensitive and reliable assay to quantify prediagnostic levels of seven markers related to endogenous hormone metabolism. METHODS: Hormones were quantified in baseline serum collected from postmenopausal women in a cohort study nested within the Breast and Bone Follow-up to the Fracture Intervention Trial (B∼FIT). Women using exogenous hormones at baseline (1992-1993) were excluded. Incident endometrial (n = 65) and ovarian (n = 67) cancers were diagnosed during 12 follow-up years and compared with a subcohort of 345 women (no hysterectomy) and 413 women (no oophorectomy), respectively. Cox models with robust variance were used to estimate cancer risk. RESULTS: Circulating progesterone levels were not associated with endometrial [tertile (T)3 vs. T1 HR (95% confidence interval): 1.87 (0.85-4.11); P trend = 0.17] or ovarian cancer risk [1.16 (0.58-2.33); 0.73]. Increasing levels of the progesterone-to-estradiol ratio were inversely associated with endometrial cancer risk [T3 vs. T1: 0.29 (0.09-0.95); 0.03]. Increasing levels of 17-hydroxypregnenolone were inversely associated with endometrial cancer risk [0.40 (0.18-0.91); 0.03] and positively associated with ovarian cancer risk [3.11 (1.39-6.93); 0.01]. CONCLUSIONS: Using sensitive and reliable assays, this study provides novel data that endogenous progesterone levels are not strongly associated with incident endometrial or ovarian cancer risks. 17-hydroxypregnenolone was positively associated with ovarian cancer and inversely associated with endometrial cancer. IMPACT: While our results require replication in large studies, they provide further support of the hormonal etiology of endometrial and ovarian cancers.


Asunto(s)
Neoplasias Endometriales/sangre , Neoplasias Ováricas/sangre , Pregnenolona/sangre , Progesterona/sangre , Anciano , Biomarcadores/sangre , Estudios de Casos y Controles , Estudios de Cohortes , Neoplasias Endometriales/epidemiología , Estradiol/sangre , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/epidemiología , Posmenopausia/sangre , Estudios Prospectivos , Factores de Riesgo
18.
JACC Clin Electrophysiol ; 7(5): 662-670, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33516710

RESUMEN

OBJECTIVES: This study sought to identify acute changes in human atrial electrophysiology during alcohol exposure. BACKGROUND: The mechanism by which a discrete episode of atrial fibrillation (AF) occurs remains unknown. Alcohol appears to increase the risk for AF, providing an opportunity to study electrophysiologic effects that may render the heart prone to arrhythmia. METHODS: In this randomized, double-blinded, placebo-controlled trial, intravenous alcohol titrated to 0.08% blood alcohol concentration was compared with a volume and osmolarity-matched, masked, placebo in patients undergoing AF ablation procedures. Right, left, and pulmonary vein atrial effective refractory periods (AERPs) and conduction times were measured pre- and post-infusion. Isoproterenol infusions and burst atrial pacing were used to assess AF inducibility. RESULTS: Of 100 participants (50 in each group), placebo recipients were more likely to be diabetic (22% vs. 4%; p = 0.007) and to have undergone a prior AF ablation (36% vs. 22%; p = 0.005). Pulmonary vein AERPs decreased an average of 12 ms (95% confidence interval: 1 to 22 ms; p = 0.026) in the alcohol group, with no change in the placebo group (p = 0.98). Whereas no statistically significant differences in continuously assessed AERPs were observed, the proportion of AERP sites tested that decreased with alcohol (median: 0.5; interquartile range: 0.6 to 0.6) was larger than with placebo (median: 0.4; interquartile range: 0.2 to 0.6; p = 0.0043). No statistically significant differences in conduction times or in the proportion with inducible AF were observed. CONCLUSIONS: Acute exposure to alcohol reduces AERP, particularly in the pulmonary veins. These data demonstrate a direct mechanistic link between alcohol, a common lifestyle exposure, and immediate proarrhythmic effects in human atria. (How Alcohol Induces Atrial Tachyarrhythmias Study [HOLIDAY]; NCT01996943).


Asunto(s)
Nivel de Alcohol en Sangre , Venas Pulmonares , Electrofisiología Cardíaca , Método Doble Ciego , Atrios Cardíacos , Sistema de Conducción Cardíaco , Humanos
19.
J Clin Endocrinol Metab ; 106(3): e1156-e1169, 2021 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-33326040

RESUMEN

CONTEXT: Follicle-stimulating hormone (FSH) concentrations increase during the perimenopausal transition and remain high after menopause. Loss of bone mineral density (BMD) and gain of bone marrow adiposity (BMA) and body fat mass also occur during this time. In mice, blocking the action of FSH increases bone mass and decreases fat mass. OBJECTIVE: To investigate the associations between endogenous FSH levels and BMD, BMA, and body composition in older adults, independent of estradiol and testosterone levels. DESIGN, SETTING, AND PARTICIPANTS: Older adults from the AGES-Reykjavik Study, an observational cohort study. MAIN OUTCOME MEASURES: Areal BMD, total body fat, and lean mass were measured with dual-energy x-ray absorptiometry. Lumbar vertebral BMA was measured by 1H-magnetic resonance spectroscopy. Volumetric BMD and visceral and subcutaneous adipose tissue (VAT, SAT) areas were measured with quantitative computed tomography. The least squares means procedure was used to determine sex hormone-adjusted associations between quartiles of serum FSH and BMD, BMA, and body composition. RESULTS: In women (N = 238, mean age 81 years), those in the highest FSH quartile, compared with the lowest quartile, had lower adjusted mean spine integral BMD (-8.6%), lower spine compressive strength index (-34.8%), higher BMA (+8.4%), lower weight (-8.4%), lower VAT (-17.6%), lower lean mass (-6.1%), and lower fat mass (-11.9%) (all P < 0.05). In men, FSH level was not associated with any outcome. CONCLUSIONS: Older postmenopausal women with higher FSH levels have higher BMA, but lower BMD and lower fat and lean mass, independent of estradiol and testosterone levels. Longitudinal studies are needed to better understand the underlying mechanisms.


Asunto(s)
Composición Corporal/fisiología , Densidad Ósea/fisiología , Médula Ósea/metabolismo , Hormona Folículo Estimulante/sangre , Adiposidad/fisiología , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Envejecimiento/metabolismo , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Islandia , Metabolismo de los Lípidos/fisiología , Estudios Longitudinales , Masculino
20.
N Engl J Med ; 356(18): 1809-22, 2007 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-17476007

RESUMEN

BACKGROUND: A single infusion of intravenous zoledronic acid decreases bone turnover and improves bone density at 12 months in postmenopausal women with osteoporosis. We assessed the effects of annual infusions of zoledronic acid on fracture risk during a 3-year period. METHODS: In this double-blind, placebo-controlled trial, 3889 patients (mean age, 73 years) were randomly assigned to receive a single 15-minute infusion of zoledronic acid (5 mg) and 3876 were assigned to receive placebo at baseline, at 12 months, and at 24 months; the patients were followed until 36 months. Primary end points were new vertebral fracture (in patients not taking concomitant osteoporosis medications) and hip fracture (in all patients). Secondary end points included bone mineral density, bone turnover markers, and safety outcomes. RESULTS: Treatment with zoledronic acid reduced the risk of morphometric vertebral fracture by 70% during a 3-year period, as compared with placebo (3.3% in the zoledronic-acid group vs. 10.9% in the placebo group; relative risk, 0.30; 95% confidence interval [CI], 0.24 to 0.38) and reduced the risk of hip fracture by 41% (1.4% in the zoledronic-acid group vs. 2.5% in the placebo group; hazard ratio, 0.59; 95% CI, 0.42 to 0.83). Nonvertebral fractures, clinical fractures, and clinical vertebral fractures were reduced by 25%, 33%, and 77%, respectively (P<0.001 for all comparisons). Zoledronic acid was also associated with a significant improvement in bone mineral density and bone metabolism markers. Adverse events, including change in renal function, were similar in the two study groups. However, serious atrial fibrillation occurred more frequently in the zoledronic acid group (in 50 vs. 20 patients, P<0.001). CONCLUSIONS: A once-yearly infusion of zoledronic acid during a 3-year period significantly reduced the risk of vertebral, hip, and other fractures. (ClinicalTrials.gov number, NCT00049829.)


Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Difosfonatos/administración & dosificación , Fracturas Óseas/prevención & control , Imidazoles/administración & dosificación , Osteoporosis Posmenopáusica/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/inducido químicamente , Biomarcadores/metabolismo , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Método Doble Ciego , Esquema de Medicación , Femenino , Fracturas Óseas/epidemiología , Fracturas de Cadera/epidemiología , Fracturas de Cadera/prevención & control , Humanos , Imidazoles/efectos adversos , Incidencia , Infusiones Intravenosas , Riesgo , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/prevención & control , Ácido Zoledrónico
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