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https://www.readbyqxmd.com/read/28721839/branched-chain-amino-acid-meat-intake-and-risk-of-type-2-diabetes-in-the-women-s-health-initiative
#1
Masoud Isanejad, Andrea Z LaCroix, Cynthia A Thomson, Lesley Tinker, Joseph C Larson, Qibin Qi, Lihong Qi, Rhonda M Cooper-DeHoff, Lawrence S Phillips, Ross L Prentice, Jeannette M Beasley
Knowledge regarding association of dietary branched-chain amino acid (BCAA) and type 2 diabetes (T2D), and the contribution of BCAA from meat to the risk of T2D are scarce. We evaluated associations between dietary BCAA intake, meat intake, interaction between BCAA and meat intake and risk of T2D. Data analyses were performed for 74 155 participants aged 50-79 years at baseline from the Women's Health Initiative for up to 15 years of follow-up. We excluded from analysis participants with treated T2D, and factors potentially associated with T2D or missing covariate data...
June 2017: British Journal of Nutrition
https://www.readbyqxmd.com/read/28685629/examining-the-association-of-smoking-with-work-productivity-and-associated-costs-in-japan
#2
Kiyomi Suwa, Natalia M Flores, Reiko Yoshikawa, Rei Goto, Jeffrey Vietri, Ataru Igarashi
AIMS: Smoking is associated with significant health and economic burden globally, including an increased risk of many leading causes of mortality and significant impairments in work productivity. This burden is attenuated by successful tobacco cessation, including reduced risk of disease and improved productivity. The current study aimed to show the benefits of smoking cessation for workplace productivity and decreased costs associated with loss of work impairment. MATERIALS AND METHODS: Data source was the 2011 Japan National Health and Wellness Survey (N = 30,000)...
July 7, 2017: Journal of Medical Economics
https://www.readbyqxmd.com/read/28684882/ignorability-for-general-longitudinal-data
#3
D M Farewell, C Huang, V Didelez
Likelihood factors that can be disregarded for inference are termed ignorable. We demonstrate that close ties exist between ignorability and identification of causal effects by covariate adjustment. A graphical condition, stability, plays a role analogous to that of missingness at random, but is applicable to general longitudinal data. Our formulation of ignorability does not depend on any notion of missing data, so is appealing in situations where missing data may not actually exist. Several examples illustrate how stability may be assessed...
June 2017: Biometrika
https://www.readbyqxmd.com/read/28680718/prognostic-factor-analysis-of-overall-survival-in-gastric-cancer-from-two-phase-iii-studies-of-second-line-ramucirumab-regard-and-rainbow-using-pooled-patient-data
#4
Charles S Fuchs, Kei Muro, Jiri Tomasek, Eric Van Cutsem, Jae Yong Cho, Sang-Cheul Oh, Howard Safran, György Bodoky, Ian Chau, Yasuhiro Shimada, Salah-Eddin Al-Batran, Rodolfo Passalacqua, Atsushi Ohtsu, Michael Emig, David Ferry, Kumari Chandrawansa, Yanzhi Hsu, Andreas Sashegyi, Astra M Liepa, Hansjochen Wilke
PURPOSE: To identify baseline prognostic factors for survival in patients with disease progression, during or after chemotherapy for the treatment of advanced gastric or gastroesophageal junction (GEJ) cancer. MATERIALS AND METHODS: We pooled data from patients randomized between 2009 and 2012 in 2 phase III, global double-blind studies of ramucirumab for the treatment of advanced gastric or GEJ adenocarcinoma following disease progression on first-line platinum- and/or fluoropyrimidine-containing therapy (REGARD and RAINBOW)...
June 2017: Journal of Gastric Cancer
https://www.readbyqxmd.com/read/28679340/a-robust-imputation-method-for-missing-responses-and-covariates-in-sample-selection-models
#5
Emmanuel O Ogundimu, Gary S Collins
Sample selection arises when the outcome of interest is partially observed in a study. Although sophisticated statistical methods in the parametric and non-parametric framework have been proposed to solve this problem, it is yet unclear how to deal with selectively missing covariate data using simple multiple imputation techniques, especially in the absence of exclusion restrictions and deviation from normality. Motivated by the 2003-2004 NHANES data, where previous authors have studied the effect of socio-economic status on blood pressure with missing data on income variable, we proposed the use of a robust imputation technique based on the selection-t sample selection model...
January 1, 2017: Statistical Methods in Medical Research
https://www.readbyqxmd.com/read/28679147/at-risk-alcohol-use-is-associated-with-antiretroviral-treatment-nonadherence-among-adults-living-with-hiv-aids
#6
Emily W Paolillo, Assawin Gongvatana, Anya Umlauf, Scott L Letendre, David J Moore
BACKGROUND: Alcohol use is a risk factor for nonadherence to antiretroviral therapy (ART) among people living with HIV/AIDS (PLWHA); however, differences in ART adherence across levels of alcohol use are unclear. This study examined whether "at-risk" alcohol use, defined by National Institute of Alcohol Abuse and Alcoholism guidelines, was associated with ART nonadherence among PLWHA. METHODS: Participants were 535 HIV-infected adults enrolled in studies at the HIV Neurobehavioral Research Program...
August 2017: Alcoholism, Clinical and Experimental Research
https://www.readbyqxmd.com/read/28678790/risk-of-hospitalization-with-neurodegenerative-disease-after-moderate-to-severe-traumatic-brain-injury-in-the-working-age-population-a-retrospective-cohort-study-using-the-finnish-national-health-registries
#7
Rahul Raj, Jaakko Kaprio, Miikka Korja, Era D Mikkonen, Pekka Jousilahti, Jari Siironen
BACKGROUND: Previous epidemiological studies suggest that working-aged persons with a history of moderate-to-severe traumatic brain injury (TBI) may have an increased risk for developing neurodegenerative disease (NDD) while persons with a history of mild TBI do not. In this comprehensive nationwide study in Finland, we assessed the risk of NDD and history of moderate-to-severe TBI in the working-age population. METHODS AND FINDINGS: We performed a population-based follow-up study using the Finnish Care Register for Health Care to identify all persons between the ages of 18 and 65 years hospitalized during 1987-2014 due to TBI who did not have a baseline NDD diagnosis...
July 2017: PLoS Medicine
https://www.readbyqxmd.com/read/28676374/reduced-incidence-of-intraoperative-femur-fracture-with-a-second-generation-tapered-wedge-stem
#8
Andrew N Fleischman, Max M Schubert, Camilo Restrepo, Antonia F Chen, Richard H Rothman
BACKGROUND: Intraoperative fractures during total hip arthroplasty (THA) are more common when using cementless stems. The purpose of this study was to investigate the impact of a new shorter second-generation cementless, tapered wedge stem with improved proximal femoral fit in reducing the incidence of intraoperative fracture. METHODS: A retrospective study was conducted on primary THA cases performed at a single institution using a first-generation or second-generation cementless stem from 2006-2016...
June 17, 2017: Journal of Arthroplasty
https://www.readbyqxmd.com/read/28668276/a-walking-intervention-among-men-with-prostate-cancer-a-pilot-study
#9
Claire H Pernar, Katja Fall, Jennifer R Rider, Sarah C Markt, Hans-Olov Adami, Sven-Olof Andersson, Unnur Valdimarsdottir, Ove Andrén, Lorelei A Mucci
BACKGROUND: Men diagnosed with prostate cancer have increased risk for disease progression, cardiovascular events, and impairments in quality of life. This pilot study evaluated the feasibility of a randomized walking group intervention to improve quality of life, circulating biomarkers, and morbidity among men with newly diagnosed prostate cancer. METHODS: Men were recruited at Örebro University Hospital, Sweden, and randomized to an 11-week walking group intervention (n = 21) or usual care (n = 20)...
May 31, 2017: Clinical Genitourinary Cancer
https://www.readbyqxmd.com/read/28656686/estimation-of-genetic-risk-function-with-covariates-in-the-presence-of-missing-genotypes
#10
Annie J Lee, Karen Marder, Roy N Alcalay, Helen Mejia-Santana, Avi Orr-Urtreger, Nir Giladi, Susan Bressman, Yuanjia Wang
In genetic epidemiological studies, family history data are collected on relatives of study participants and used to estimate the age-specific risk of disease for individuals who carry a causal mutation. However, a family member's genotype data may not be collected because of the high cost of in-person interview to obtain blood sample or death of a relative. Previously, efficient nonparametric genotype-specific risk estimation in censored mixture data has been proposed without considering covariates. With multiple predictive risk factors available, risk estimation requires a multivariate model to account for additional covariates that may affect disease risk simultaneously...
June 27, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/28653759/trends-in-socioeconomic-inequalities-in-oral-health-among-15-year-old-danish-adolescents-during-1995-2013-a-nationwide-register-based-repeated-cross-sectional-study
#11
Kaushik Sengupta, Lisa Bøge Christensen, Laust Hvas Mortensen, Lene Theil Skovgaard, Ingelise Andersen
BACKGROUND: Scandinavian welfare states, despite having better population oral health than less egalitarian societies, are characterized by ubiquitous social gradients and large relative socioeconomic inequalities in oral health. However, trends in these inequalities among Scandinavian children and adolescents have not been studied in detail. OBJECTIVES: To describe the associations between socioeconomic position (SEP) and oral health in adolescents and to investigate the trends in these associations between 1995 and 2013...
June 27, 2017: Community Dentistry and Oral Epidemiology
https://www.readbyqxmd.com/read/28642364/the-accuracy-and-bias-of-single-step-genomic-prediction-for-populations-under-selection
#12
Wan-Ling Hsu, Dorian J Garrick, Rohan Luigi Fernando
In single-step analyses, missing genotypes are explicitly or implicitly imputed, and this requires centering the observed genotypes, using the means of the unselected founders. If genotypes are only available on selected individuals, centering on the unselected founder mean is not straightforward. Here, computer simulation is used to study an alternative analysis that does not require centering genotypes but fits the mean μg of unselected individuals as a fixed effect. Centering the entire matrix of observed and imputed genotypes using their sample means can be done to improve numerical properties of the analysis, in addition to fitting μg...
July 10, 2017: G3: Genes—Genomes—Genetics
https://www.readbyqxmd.com/read/28641921/genome-wide-association-and-interaction-studies-of-csf-t-tau-a%C3%AE-42-ratio-in-adni-cohort
#13
Jin Li, Qiushi Zhang, Feng Chen, Xianglian Meng, Wenjie Liu, Dandan Chen, Jingwen Yan, Sungeun Kim, Lei Wang, Weixing Feng, Andrew J Saykin, Hong Liang, Li Shen
The pathogenic relevance in Alzheimer's disease (AD) presents a decrease of cerebrospinal fluid amyloid-ß42 (Aß42) burden and an increase in cerebrospinal fluid total tau (T-tau) levels. In this work, we performed genome-wide association study (GWAS) and genome-wide interaction study of T-tau/Aß42 ratio as an AD imaging quantitative trait on 843 subjects and 563,980 single-nucleotide polymorphisms (SNPs) in ADNI cohort. We aim to identify not only SNPs with significant main effects but also SNPs with interaction effects to help explain "missing heritability"...
May 15, 2017: Neurobiology of Aging
https://www.readbyqxmd.com/read/28635678/evaluation-of-classifier-performance-for-multiclass-phenotype-discrimination-in-untargeted-metabolomics
#14
Patrick J Trainor, Andrew P DeFilippis, Shesh N Rai
Statistical classification is a critical component of utilizing metabolomics data for examining the molecular determinants of phenotypes. Despite this, a comprehensive and rigorous evaluation of the accuracy of classification techniques for phenotype discrimination given metabolomics data has not been conducted. We conducted such an evaluation using both simulated and real metabolomics datasets, comparing Partial Least Squares-Discriminant Analysis (PLS-DA), Sparse PLS-DA, Random Forests, Support Vector Machines (SVM), Artificial Neural Network, k-Nearest Neighbors (k-NN), and Naïve Bayes classification techniques for discrimination...
June 21, 2017: Metabolites
https://www.readbyqxmd.com/read/28632787/risk-of-alzheimer-s-disease-or-dementia-following-a-cancer-diagnosis
#15
Erin J Aiello Bowles, Rod L Walker, Melissa L Anderson, Sascha Dublin, Paul K Crane, Eric B Larson
OBJECTIVE: We evaluated dementia and Alzheimer's disease (AD) risks after a cancer diagnosis in a population-based prospective cohort, the Adult Changes in Thought (ACT) study. METHODS: We followed community-dwelling people aged ≥65 years without dementia at study entry for incident dementia and AD from 1994-2015. We linked study data with cancer registry data and categorized cancer diagnoses as prevalent (diagnosed before ACT study enrollment) or incident (diagnosed during follow-up)...
2017: PloS One
https://www.readbyqxmd.com/read/28631331/missing-data-in-clinical-trials-control-based-mean-imputation-and-sensitivity-analysis
#16
Devan V Mehrotra, Fang Liu, Thomas Permutt
In some randomized (drug versus placebo) clinical trials, the estimand of interest is the between-treatment difference in population means of a clinical endpoint that is free from the confounding effects of "rescue" medication (e.g., HbA1c change from baseline at 24 weeks that would be observed without rescue medication regardless of whether or when the assigned treatment was discontinued). In such settings, a missing data problem arises if some patients prematurely discontinue from the trial or initiate rescue medication while in the trial, the latter necessitating the discarding of post-rescue data...
June 20, 2017: Pharmaceutical Statistics
https://www.readbyqxmd.com/read/28629879/prediction-of-cognition-in-parkinson-s-disease-with-a-clinical-genetic-score-a-longitudinal-analysis-of-nine-cohorts
#17
Ganqiang Liu, Joseph J Locascio, Jean-Christophe Corvol, Brendon Boot, Zhixiang Liao, Kara Page, Daly Franco, Kyle Burke, Iris E Jansen, Ana Trisini-Lipsanopoulos, Sophie Winder-Rhodes, Caroline M Tanner, Anthony E Lang, Shirley Eberly, Alexis Elbaz, Alexis Brice, Graziella Mangone, Bernard Ravina, Ira Shoulson, Florence Cormier-Dequaire, Peter Heutink, Jacobus J van Hilten, Roger A Barker, Caroline H Williams-Gray, Johan Marinus, Clemens R Scherzer
BACKGROUND: Cognitive decline is a debilitating manifestation of disease progression in Parkinson's disease. We aimed to develop a clinical-genetic score to predict global cognitive impairment in patients with the disease. METHODS: In this longitudinal analysis, we built a prediction algorithm for global cognitive impairment (defined as Mini Mental State Examination [MMSE] ≤25) using data from nine cohorts of patients with Parkinson's disease from North America and Europe assessed between 1986 and 2016...
August 2017: Lancet Neurology
https://www.readbyqxmd.com/read/28606970/the-dynamics-of-response-as-measured-by-multiple-composite-outcome-tools-in-the-tight-control-of-inflammation-in-early-psoriatic-arthritis-ticopa-trial
#18
Laura C Coates, Farrouq Mahmood, Paul Emery, Philip G Conaghan, Philip S Helliwell
BACKGROUND: We aimed to evaluate the dynamics of treatment response with different composite measures in the TIght COntrol of inflammation in early Psoriatic Arthritis (TICOPA) trial. METHODS: Participants with early disease-modifying antirheumatic drug-naïve psoriatic arthritis (PsA) were randomised 1:1 to either tight control (TC; 4 weekly review with therapy escalation if criteria not met) or standard care (SC; 12 weekly review). We calculated modified versions of the Psoriatic ArthritiS Disease Activity Score (PASDAS), Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) Composite scorE (GRACE) and Composite Psoriatic Disease Activity Index (CPDAI) at baseline and 12 weekly to 48 weeks by blinded assessor...
June 12, 2017: Annals of the Rheumatic Diseases
https://www.readbyqxmd.com/read/28599749/statin-prescribing-for-prevention-of-cardiovascular-disease-amongst-people-with-severe-mental-illness-cohort-study-in-uk-primary-care
#19
R Blackburn, D Osborn, K Walters, I Nazareth, I Petersen
BACKGROUND: Severe mental illness (SMI) is associated with excess cardiovascular disease (CVD) morbidity, but little is known on provision of preventative interventions. We investigated statin initiation for primary CVD prevention in individuals with and without SMI. METHODS: We used primary care data from The Health Improvement Network from 2006 to 2015 for UK patients aged 30-99years with no pre-existing CVD conditions and selected individuals with schizophrenia (n=13,252) or bipolar disorder (n=11,994)...
June 6, 2017: Schizophrenia Research
https://www.readbyqxmd.com/read/28584366/biostatistics-series-module-9-survival-analysis
#20
Avijit Hazra, Nithya Gogtay
Survival analysis is concerned with "time to event" data. Conventionally, it dealt with cancer death as the event in question, but it can handle any event occurring over a time frame, and this need not be always adverse in nature. When the outcome of a study is the time to an event, it is often not possible to wait until the event in question has happened to all the subjects, for example, until all are dead. In addition, subjects may leave the study prematurely. Such situations lead to what is called censored observations as complete information is not available for these subjects...
May 2017: Indian Journal of Dermatology
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