43 research outputs found
Predictors of Chronic Opioid Therapy in Medicaid Beneficiaries with HIV Who Initiated Antiretroviral Therapy
The factors associated with chronic opioid therapy (COT) in patients with HIV is understudied. Using Medicaid data (2002-2009), this retrospective cohort study examines COT in beneficiaries with HIV who initiated standard combination anti-retroviral therapy (cART). We used generalized estimating equations on logistic regression models with backward selection to identify significant predictors of COT initiation. COT was initiated among 1014 out of 9615 beneficiaries with HIV (male: 10.4%; female: 10.7%). Those with older age, any malignancy, Hepatitis C infection, back pain, arthritis, neuropathy pain, substance use disorder, polypharmacy, (use of) benzodiazepines, gabapentinoids, antidepressants, and prior opioid therapies were positively associated with COT. In sex-stratified analyses, multiple predictors were shared between male and female beneficiaries; however, chronic obstructive pulmonary disease, liver disease, any malignancy, and antipsychotic therapy were unique to female beneficiaries. Comorbidities and polypharmacy were important predictors of COT in Medicaid beneficiaries with HIV who initiated cART
Evaluating the incident user design in the HIV population: incident use versus naive?
INTRODUCTION: The incident user design is the preferred study design in comparative effectiveness (CER) research. Usually, 180-365 days of exposure free time is adequate to remove biases associated with inclusion of prevalent users. In HIV research, the use of antiretrovirals (ARVs) at any time in the past may influence future treatment choices and CER results; thus, identifying naive as opposed to incident users is of importance. We examined misclassification of antiretroviral naive status based on Medicaid administrative data through linkage to the UNC CFAR HIV Clinical Cohort (UCHCC).
METHODS: We identified Medicaid patients with incident exposure to common first-line ARV regimens between 2002 and 2008 that were also patients enrolled in the UCHCC. We calculated the proportion of antiretroviral naive patients based on the UCHCC, among patients identified as having incident exposure in Medicaid and examined factors associated with being antiretroviral naive in both data sources using logistic regression to generate prevalence odds ratios and associated 95% confidence intervals.
RESULTS: Of the 3500 Medicaid patients with incident antiretroviral (ARV) exposure, 1344 were also enrolled in the UCHCC. In this sample, 34% were antiretroviral naive at the time of first exposure in the Medicaid data based on the UCHCC. In multivariable models, higher CD4 cell counts and log HIV RNA values were associated with being antiretroviral naive in both data sources.
CONCLUSIONS: Administrative data are an important source of information related to HIV treatment. As the construction of a durable and long-lasting HIV treatment plan involves knowledge of current and past antiretroviral therapy, augmentation of this data with comprehensive clinical cohort information is necessary
Effects of Combination Antiretroviral Therapies on the Risk of Myocardial Infarction Among HIV Patients
Cohort studies have demonstrated greater risk of myocardial infarction (MI) associated with specific antiretroviral use, while meta-analyses of randomized controlled trials have not. These differences may be due to inherent biases in the observational study design or to the limited duration of randomized trials. We conducted a new-user, active-comparator cohort study emulating a randomized controlled trial comparing initiation of several antiretrovirals as part of combination antiretroviral therapy (cART) and MI
Validation of Medicaid Claims-based Diagnosis of Myocardial Infarction Using an HIV Clinical Cohort
In non-experimental comparative effectiveness research using healthcare databases, outcome measurements must be validated to evaluate and potentially adjust for misclassification bias. We aimed to validate claims-based myocardial infarction algorithms in a Medicaid population using an HIV clinical cohort as the gold standard
The social value of a QALY : raising the bar or barring the raise?
Background: Since the inception of the National Institute for Health and Clinical Excellence (NICE) in England,
there have been questions about the empirical basis for the cost-per-QALY threshold used by NICE and whether
QALYs gained by different beneficiaries of health care should be weighted equally. The Social Value of a QALY
(SVQ) project, reported in this paper, was commissioned to address these two questions. The results of SVQ were
released during a time of considerable debate about the NICE threshold, and authors with differing perspectives
have drawn on the SVQ results to support their cases. As these discussions continue, and given the selective use of
results by those involved, it is important, therefore, not only to present a summary overview of SVQ, but also for
those who conducted the research to contribute to the debate as to its implications for NICE.
Discussion: The issue of the threshold was addressed in two ways: first, by combining, via a set of models, the
current UK Value of a Prevented Fatality (used in transport policy) with data on fatality age, life expectancy and
age-related quality of life; and, second, via a survey designed to test the feasibility of combining respondents’
answers to willingness to pay and health state utility questions to arrive at values of a QALY. Modelling resulted in
values of £10,000-£70,000 per QALY. Via survey research, most methods of aggregating the data resulted in values
of a QALY of £18,000-£40,000, although others resulted in implausibly high values. An additional survey, addressing
the issue of weighting QALYs, used two methods, one indicating that QALYs should not be weighted and the
other that greater weight could be given to QALYs gained by some groups.
Summary: Although we conducted only a feasibility study and a modelling exercise, neither present compelling
evidence for moving the NICE threshold up or down. Some preliminary evidence would indicate it could be
moved up for some types of QALY and down for others. While many members of the public appear to be open to
the possibility of using somewhat different QALY weights for different groups of beneficiaries, we do not yet have
any secure evidence base for introducing such a system
Is HIV Infection a Risk Factor for Multi-Drug Resistant Tuberculosis? A Systematic Review
BACKGROUND:Tuberculosis (TB) is an important cause of human suffering and death. Human immunodeficiency virus (HIV), multi-drug resistant TB (MDR-TB), and extensive drug resistant tuberculosis (XDR-TB) have emerged as threats to TB control. The association between MDR-TB and HIV infection has not yet been fully investigated. We conducted a systematic review and meta-analysis to summarize the evidence on the association between HIV infection and MDR-TB. METHODS AND RESULTS:Original studies providing Mycobacterium tuberculosis resistance data stratified by HIV status were identified using MEDLINE and ISI Web of Science. Crude MDR-TB prevalence ratios were calculated and analyzed by type of TB (primary or acquired), region and study period. Heterogeneity across studies was assessed, and pooled prevalence ratios were generated if appropriate. No clear association was found between MDR-TB and HIV infection across time and geographic locations. MDR-TB prevalence ratios in the 32 eligible studies, comparing MDR-TB prevalence by HIV status, ranged from 0.21 to 41.45. Assessment by geographical region or study period did not reveal noticeable patterns. The summary prevalence ratios for acquired and primary MDR-TB were 1.17 (95% CI 0.86, 1.6) and 2.72 (95% CI 2.03, 3.66), respectively. Studies eligible for review were few considering the size of the epidemics. Most studies were not adjusted for confounders and the heterogeneity across studies precluded the calculation of a meaningful overall summary measure. CONCLUSIONS:We could not demonstrate an overall association between MDR-TB and HIV or acquired MDR-TB and HIV, but our results suggest that HIV infection is associated with primary MDR-TB. Future well-designed studies and surveillance in all regions of the world are needed to better clarify the relationship between HIV infection and MDR-TB
Current commands for high-efficiency torque control of DC shunt motor
The current commands for a high-efficiency torque control of a DC shunt motor are described. In the proposed control method, the effect of a magnetic saturation and an armature reaction are taken into account by representing the coefficients of an electromotive force and a torque as a function of the field current, the armature current and the revolving speed. The current commands at which the loss of the motor drive system becomes a minimum are calculated as an optimal problem. The proposed control technique of a motor is implemented on the microprocessor-based control system. The effect of the consideration of the magnetic saturation and the armature reaction on the produced torque and the minimisation of the loss are discussed analytically and experimentally </p
Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.
Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field
ENIGMA and global neuroscience: A decade of large-scale studies of the brain in health and disease across more than 40 countries
This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors
The genetic architecture of the human cerebral cortex
The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder