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1.
J Gen Intern Med ; 35(12): 3605-3612, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32989711

RESUMEN

BACKGROUND: Contrary to guidelines, magnetic resonance imaging (MRI) is often ordered in the first 6 weeks of new episodes of uncomplicated non-specific low back pain. OBJECTIVE: To determine the downstream consequences of early imaging. DESIGN: Retrospective matched cohort study using data from electronic health records of primary care clinics of the U.S. Department of Veterans Affairs. PARTICIPANTS: Patients seeking primary care for non-specific low back pain without a red flag condition or an encounter for low back pain in the prior 6 months (N = 405,965). EXPOSURE: MRI of the lumbar spine within 6 weeks of the initial primary care visit. MAIN MEASURES: Covariates included patient demographics, health history in the prior year, and baseline pain. Outcomes were lumbar surgery, prescription opioid use, acute health care costs, and last pain score recorded within 1 year of the index visit. KEY RESULTS: Early MRI was associated with more back surgery (1.48% vs. 0.12% in episodes without early MRI), greater use of prescription opioids (35.1% vs. 28.6%), a higher final pain score (3.99 vs. 3.87), and greater acute care costs ($8082 vs. $5560), p < 0.001 for all comparisons. LIMITATIONS: Reliance on data gathered in normal clinical care and the potential for residual confounding despite the use of coarsened exact matching weights to adjust for baseline differences. CONCLUSIONS: The association between early imaging and increased utilization was apparent even in a setting largely unaffected by incentives of fee-for-service care. Reduced imaging cost is only part of the motivation to improve adherence with guidelines for the use of MRI. Early scans are associated with excess surgery, higher costs for other care, and worse outcomes, including potential harms from prescription opioids.


Asunto(s)
Dolor de la Región Lumbar , Vértebras Lumbares , Estudios de Cohortes , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Imagen por Resonancia Magnética , Estudios Retrospectivos
2.
J Gen Intern Med ; 35(4): 1044-1051, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31832927

RESUMEN

BACKGROUND: Clinical practice guidelines suggest that magnetic resonance imaging of the lumbar spine (LS-MRI) is unneeded during the first 6 weeks of acute, uncomplicated low-back pain. Unneeded LS-MRIs do not improve patient outcomes, lead to unnecessary surgeries and procedures, and cost the US healthcare system about $300 million dollars per year. However, why primary care providers (PCPs) order unneeded LS-MRI for acute, uncomplicated low-back pain is poorly understood. OBJECTIVE: To characterize and explain the factors contributing to PCPs ordering unneeded LS-MRI for acute, uncomplicated low-back pain. DESIGN: Qualitative study using semi-structured interviews. PARTICIPANTS: Veterans Affairs PCPs identified from administrative data as having high or low rates of guideline-concordant LS-MRI ordering in 2016. APPROACH: Providers were interviewed about their use of LS-MRI for acute, uncomplicated low-back pain and factors contributing to their decision-making. Directed content analysis of transcripts was conducted to identify and compare environmental-, patient-, and provider-level factors contributing to unneeded LS-MRI. KEY RESULTS: Fifty-five PCPs participated (8.6% response rate). Both low (n = 33) and high (n = 22) guideline-concordant providers reported that LS-MRIs were required for specialty care referrals, but they differed in how other environmental factors (stringency of radiology utilization review, management of patient travel burden, and time constraints) contributed to LS-MRI ordering patterns. Low- and high-guideline-concordant providers reported similar patient factors (beliefs in value of imaging and pressure on providers). However, provider groups differed in how provider-level factors (guideline familiarity and agreement, the extent to which they acquiesced to patients, and belief in the value of LS-MRI) contributed to LS-MRI ordering patterns. CONCLUSIONS: Results describe how diverse environmental, patient, and provider factors contribute to unneeded LS-MRI for acute, uncomplicated low-back pain. Prior research using a single intervention to reduce unneeded LS-MRI has been ineffective. Results suggest that multifaceted de-implementation strategies may be required to reduce unneeded LS-MRI.


Asunto(s)
Dolor Agudo , Dolor de la Región Lumbar , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Vértebras Lumbares , Imagen por Resonancia Magnética , Atención Primaria de Salud
3.
Pain Med ; 21(12 Suppl 2): S110-S117, 2020 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-33313731

RESUMEN

BACKGROUND: Veterans with significant chronic pain from musculoskeletal disorders are at risk of substance misuse. Veterans whose condition is the result of military service may be eligible for a disability pension. Department of Veterans Affairs compensation examinations, which determine the degree of disability and whether it was connected to military service, represent an opportunity to engage Veterans in pain management and substance use treatments. A multisite randomized clinical trial is testing the effectiveness and cost-effectiveness of Screening, Brief Intervention, and Referral to Treatment for Pain Management (SBIRT-PM) for Veterans seeking compensation for musculoskeletal disorders. This telephone-based intervention is delivered through a hub-and-spoke configuration. DESIGN: This study is a two-arm, parallel-group, 36-week, multisite randomized controlled single-blind trial. It will randomize 1,100 Veterans experiencing pain and seeking service-connection for musculoskeletal disorders to either SBIRT-PM or usual care across eight New England VA medical centers. The study balances pragmatic with explanatory methodological features. Primary outcomes are pain severity and number of substances misused. Nonpharmacological pain management and substance use services utilization are tracked in the trial. SUMMARY: Early trial enrollment targets were met across sites. SBIRT-PM could help Veterans, at the time of their compensation claims, use multimodal pain treatments and reduce existing substance misuse. Strategies to address COVID-19 pandemic impacts on the SBIRT-PM protocol have been developed to maintain its pragmatic and exploratory integrity.


Asunto(s)
Dolor Crónico/tratamiento farmacológico , Enfermedades Musculoesqueléticas/terapia , Manejo del Dolor , SARS-CoV-2/efectos de los fármacos , Veteranos/psicología , Adulto , Dolor Crónico/virología , Intervención en la Crisis (Psiquiatría)/métodos , Femenino , Humanos , Masculino , Tamizaje Masivo/métodos , Enfermedades Musculoesqueléticas/complicaciones , Enfermedades Musculoesqueléticas/diagnóstico , Manejo del Dolor/métodos , SARS-CoV-2/patogenicidad , Método Simple Ciego
4.
Tob Control ; 28(5): 540-547, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30181383

RESUMEN

INTRODUCTION: In 2003, the Veterans Health Administration (VHA) implemented a directive that cessation pharmacotherapy be made available to all who use tobacco and are interested in quitting. Despite the efficacy of cessation pharmacotherapy shown in clinical trials, the generalisability of the results in real-world settings has been challenged. Hence, the specific aim of this study was to determine the effectiveness of cessation pharmacotherapies in the VHA. METHODS: This retrospective cohort study used VHA's electronic medical record data to compare quit rates among those who use tobacco and who did vs. did not receive any type of cessation pharmacotherapy. Included were 589 862 Veterans identified as current tobacco users during fiscal year 2011 who had not received cessation pharmacotherapy in the prior 12 months. Following a 6-month period to assess treatment, quit rates among those who were treated versus untreated were compared during the 7-18 months (12 months) post-treatment follow-up period. The estimated treatment effect was calculated from a logistic regression model adjusting for inverse probability of treatment weights (IPTWs) and covariates. Marginal probabilities of quitting were also obtained among those treated versus untreated. RESULTS: Adjusting for IPTWs and covariates, the odds of quitting were 24% higher among those treated versus untreated (OR=1.24, 95% CI 1.23 to 1.25, p<0.001). The marginal probabilities of quitting were 16.7% for the untreated versus 19.8% for the treated based on the weighted model. CONCLUSION: The increased quit rates among Veterans treated support the effectiveness and continuation of the VHA tobacco cessation pharmacotherapy policy.


Asunto(s)
Dispositivos para Dejar de Fumar Tabaco , Cese del Uso de Tabaco/métodos , Tabaquismo/tratamiento farmacológico , Adolescente , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Estados Unidos , United States Department of Veterans Affairs , Adulto Joven
5.
Value Health ; 21(8): 921-930, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30098669

RESUMEN

OBJECTIVES: To determine whether implementation of interferon-free treatment for hepatitis C virus (HCV) reached groups less likely to benefit from earlier therapies, including patients with genotype 1 virus or contraindications to interferon treatment, and groups that faced treatment disparities: African Americans, patients with HIV co-infection, and those with drug use disorder. METHODS: Electronic medical records of the US Veterans Health Administration (VHA) were used to characterize patients with chronic HCV infection and the treatments they received. Initiation of treatment in 206,544 patients with chronic HCV characterized by viral genotype, demographic characteristics, and comorbid medical and mental illness was studied using a competing events Cox regression over 6 years. RESULTS: With the advent of interferon-free regimens, the proportion treated increased from 2.4% in 2010 to 18.1% in 2015, an absolute increase of 15.7%. Patients with genotype 1 virus, poor response to previous treatment, and liver disease had the greatest increase. Large absolute increases in the proportion treated were observed in patients with HIV co-infection (18.6%), alcohol use disorder (11.9%), and drug use disorder (12.6%) and in African American (13.7%) and Hispanic (13.5%) patients, groups that were less likely to receive interferon-containing treatment. The VHA spent $962 million on interferon-free treatments in 2015, 1.5% of its operating budget. CONCLUSIONS: The proportion of patients with HCV treated in VHA increased sevenfold. The VHA was successful in implementing interferon treatment in previously undertreated populations, and this may become the community standard of care.


Asunto(s)
Disparidades en Atención de Salud/estadística & datos numéricos , Hepatitis C/tratamiento farmacológico , Veteranos/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Femenino , Hepacivirus/patogenicidad , Humanos , Interferones/uso terapéutico , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estados Unidos , United States Department of Veterans Affairs/organización & administración
6.
Nicotine Tob Res ; 20(10): 1173-1181, 2018 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-30184237

RESUMEN

Introduction: There is evidence suggesting that certain subgroups of people who use tobacco do not receive tobacco pharmacology as consistently as others. Methods: This retrospective, cohort study examined the trend in the use of cessation pharmacotherapy from 2004 to 2013 using Veterans Health Administration (VHA) administrative data. Among Veterans who used tobacco in the fiscal year (FY) 2011 and had not received pharmacotherapy in the prior year, multivariable Cox regression was used to assess the independent associations between patient clinical and demographic characteristics and pharmacotherapy initiation in the 6-months follow-up period. Results: Smoking cessation pharmacotherapy in the VHA increased from 13.8% in 2004 to 25.6% in 2013. In 2011, Veterans (N = 838309) who were more likely to newly receive pharmacotherapy included those with psychiatric disorders (depression, bipolar disorder, non-alcohol substance use disorder, other anxiety, and post-traumatic stress disorder), chronic pulmonary disease, peripheral vascular disorders, and younger Veterans (adjusted rate ratios (ARRs) ranged from 1.03 to 1.92, all p < .001). Veterans less likely to receive pharmacotherapy were those with schizophrenia or other psychosis, males, Hispanics, and those with a medical condition (uncomplicated diabetes, uncomplicated hypertension, fluid and electrolyte disorders, cardiac arrhythmia, valvular disease, hypothyroidism, acquired immunodeficiency syndrome/human immunodeficiency virus, deficiency anemia, renal failure, paralysis, coagulopathy, metastatic cancer, and other neurological disorders) (ARRs ranged from 0.74 to 0.93, all p < .001). Conclusions: Although VHA cessation pharmacotherapy use nearly doubled from 13.8% in 2004 to 25.6% in 2013, reaching undertreated subgroups, especially those with medical comorbidities, may improve cessation outcomes. Implications: Despite evidence that demographics influence the use of pharmacotherapy in smoking cessation, there is limited and contradictory information regarding how psychiatric and chronic medical illnesses affect pharmacotherapy use. Administrative data were used to determine trends and patient characteristics of those receiving pharmacotherapy to aid in smoking cessation in the Veterans Health Administration. From 2004 to 2013, pharmacotherapy use increased from 13.8% to 25.6% of current smokers. Factors associated with increased pharmacotherapy initiation were psychiatric disorders, chronic pulmonary disease, peripheral vascular disorders, and younger age. Veterans with schizophrenia or other psychosis, males, Hispanics, and most medical conditions were less likely to receive pharmacotherapy.


Asunto(s)
Cese del Hábito de Fumar/métodos , Cese del Hábito de Fumar/psicología , Tabaquismo/tratamiento farmacológico , Tabaquismo/psicología , United States Department of Veterans Affairs/tendencias , Veteranos/psicología , Adulto , Anciano , Ansiedad/epidemiología , Ansiedad/psicología , Ansiedad/terapia , Trastorno Bipolar/epidemiología , Trastorno Bipolar/psicología , Trastorno Bipolar/terapia , Estudios de Cohortes , Comorbilidad , Depresión/epidemiología , Depresión/psicología , Depresión/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Esquizofrenia/epidemiología , Esquizofrenia/terapia , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/psicología , Trastornos por Estrés Postraumático/terapia , Tabaquismo/epidemiología , Estados Unidos/epidemiología , Salud de los Veteranos/tendencias
7.
Hum Brain Mapp ; 38(1): 528-540, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27628031

RESUMEN

OBJECTIVE: Focal epilepsies, such as temporal lobe epilepsy (TLE), are known to disrupt network activity in areas outside the epileptogenic zone [Tracy et al., 2015]. We devised a measure of temporal instability of resting state functional connectivity (FC), capturing temporal variations of BOLD correlations between brain regions that is less confounded than the "sliding window" approach common in the literature. METHODS: We investigated healthy controls and unilateral TLE patients (right and left seizure focus groups), utilizing group ICA to identify the default mode network (DMN), a network associated with episodic memory, a key cognitive deficit in TLE. Our instability analyses focused on: (1) connectivity between DMN region pairs, both within and between TLE patients and matched controls, (2) whole brain group differences between region pairs ipsilateral or contralateral to the epileptogenic temporal lobe. RESULTS: For both the whole brain and a more focused analysis of DMN region pairs, temporal stability appears to characterize the healthy brain. The TLE patients displayed more FC instability compared to controls, with this instability more pronounced for the right TLE patients. SIGNIFICANCE: Our findings challenge the view that the resting state signal is stable over time, providing a measure of signal coherence change that may generate insights into the temporal components of network organization. The precuneus was the region within the DMN consistently expressing this instability, suggesting this region plays a key role in large scale temporal dynamics of the DMN, with such dynamics disrupted in TLE, putting key cognitive functions at risk. Hum Brain Mapp 38:528-540, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Mapeo Encefálico , Encéfalo/patología , Epilepsia Refractaria/patología , Modelos Neurológicos , Vías Nerviosas/fisiopatología , Descanso , Adulto , Encéfalo/diagnóstico por imagen , Epilepsia Refractaria/diagnóstico por imagen , Femenino , Lateralidad Funcional , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen
8.
Clin Infect Dis ; 63(1): 96-100, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27045125

RESUMEN

BACKGROUND: Guidelines now recommend limited use of routine CD4 cell count testing in human immunodeficiency virus (HIV)-infected patients with successful viral control who are not immunocompromised. METHODS: CD4 and viral load tests for patients receiving HIV care from the US Department of Veterans Affairs during 2009-2013 were evaluated to determine trends in CD4 testing frequency and the number, cost, and results of CD4 tests considered optional under the guidelines. RESULTS: There were 28 530 individuals with sufficient testing to be included. At the time of the last CD4 test, 19.8% of the cohort was eligible for optional monitoring and 15.6% for minimal monitoring. CD4 testing frequency declined by 10.8% over 4 years, reducing the direct cost of testing by US$196 000 per year. Full implementation of new treatment guidelines could reduce CD4 testing a further 28.9%, an additional annual savings of US$600 000. CD4 tests conducted during periods of potentially reduced monitoring were rarely <200 cells/µL: 1.1% of the tests conducted when minimal monitoring was recommended and just 0.3% of tests conducted when optional monitoring was recommended were less than this value. CONCLUSIONS: Reduced CD4 monitoring of HIV-infected patients would result in modest cost savings and likely reduce patient anxiety, with little or no impact on the quality of care. Veterans Affairs has made substantial progress in reducing the frequency of optional CD4 testing, but further reductions may still be warranted.


Asunto(s)
Recuento de Linfocito CD4 , Análisis Costo-Beneficio , Infecciones por VIH , Veteranos , Fármacos Anti-VIH/uso terapéutico , Recuento de Linfocito CD4/economía , Recuento de Linfocito CD4/estadística & datos numéricos , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/economía , Infecciones por VIH/virología , Humanos , Guías de Práctica Clínica como Asunto , Carga Viral
9.
Nicotine Tob Res ; 18(3): 267-74, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25943761

RESUMEN

INTRODUCTION: We examined the cost-effectiveness of smoking cessation integrated with treatment for post-traumatic stress disorder (PTSD). METHODS: Smoking veterans receiving care for PTSD (N = 943) were randomized to care integrated with smoking cessation versus referral to a smoking cessation clinic. Smoking cessation services, health care cost and utilization, quality of life, and biochemically-verified abstinence from cigarettes were assessed over 18-months of follow-up. Clinical outcomes were combined with literature on changes in smoking status and the effect of smoking on health care cost, mortality, and quality of life in a Markov model of cost-effectiveness over a lifetime horizon. We discounted cost and outcomes at 3% per year and report costs in 2010 US dollars. RESULTS: The mean of smoking cessation services cost was $1286 in those randomized to integrated care and $551 in those receiving standard care (P < .001). There were no significant differences in the cost of mental health services or other care. After 12 months, prolonged biochemically verified abstinence was observed in 8.9% of those randomized to integrated care and 4.5% of those randomized to standard care (P = .004). The model projected that Integrated Care added $836 in lifetime cost and generated 0.0259 quality adjusted life years (QALYs), an incremental cost-effectiveness ratio of $32 257 per QALY. It was 86.0% likely to be cost-effective compared to a threshold of $100 000/QALY. CONCLUSIONS: Smoking cessation integrated with treatment for PTSD was cost-effective, within a broad confidence region, but less cost-effective than most other smoking cessation programs reported in the literature.


Asunto(s)
Análisis Costo-Beneficio/métodos , Cese del Hábito de Fumar/economía , Fumar/economía , Fumar/terapia , Trastornos por Estrés Postraumático/economía , Trastornos por Estrés Postraumático/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Servicios de Salud Mental/economía , Persona de Mediana Edad , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Derivación y Consulta , Fumar/epidemiología , Cese del Hábito de Fumar/métodos , Trastornos por Estrés Postraumático/epidemiología , Estados Unidos/epidemiología , United States Department of Veterans Affairs/economía , Veteranos , Adulto Joven
10.
Qual Life Res ; 25(8): 1949-57, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26886926

RESUMEN

BACKGROUND: US veterans report lower health-related quality of life (HRQoL) relative to the general population. Identifying behavioral factors related to HRQoL that are malleable to change may inform interventions to improve well-being in this vulnerable group. PURPOSE: The current study sought to characterize HRQoL in a largely male sample of veterans in addictions treatment, both in relation to US norms and in association with five recommended health behavior practices: regularly exercising, managing stress, having good sleep hygiene, consuming fruits and vegetables, and being tobacco free. METHODS: We assessed HRQoL with 250 veterans in addictions treatment (96 % male, mean age 53, range 24-77) using scales from four validated measures. Data reduction methods identified two principal components reflecting physical and mental HRQoL. Model testing of HRQoL associations with health behaviors adjusted for relevant demographic and treatment-related covariates. RESULTS: Compared to US norms, the sample had lower HRQoL scores. Better psychological HRQoL was associated with higher subjective social standing, absence of pain or trauma, lower alcohol severity, and monotonically with the sum of health behaviors (all p < 0.05). Specifically, psychological HRQoL was associated with regular exercise, stress management, and sleep hygiene. Regular exercise also related to better physical HRQoL. The models explained >40 % of the variance in HRQoL. CONCLUSIONS: Exercise, sleep hygiene, and stress management are strongly associated with HRQoL among veterans in addictions treatment. Future research is needed to test the effect of interventions for improving well-being in this high-risk group.


Asunto(s)
Conductas Relacionadas con la Salud/efectos de los fármacos , Perfil de Impacto de Enfermedad , Trastornos Relacionados con Sustancias/psicología , Veteranos/psicología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
Clin Infect Dis ; 61(3): 445-52, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25908684

RESUMEN

BACKGROUND: To characterize the association of antiretroviral drug combinations on risk of cardiovascular events. METHODS: Certain antiretroviral medications for human immunodeficiency virus (HIV) have been implicated in increasing risk of cardiovascular disease. However, antiretroviral drugs are typically prescribed in combination. We characterized the association of current exposure to antiretroviral drug combinations on risk of cardiovascular events including myocardial infarction, stroke, percutaneous coronary intervention, and coronary artery bypass surgery. We used the Veterans Health Administration Clinical Case Registry to analyze data from 24 510 patients infected with HIV from January 1996 through December 2009. We assessed the association of current exposure to 15 antiretroviral drugs and 23 prespecified combinations of agents on the risk of cardiovascular event by using marginal structural models and Cox models extended to accommodate time-dependent variables. RESULTS: Over 164 059 person-years of follow-up, 934 patients had a cardiovascular event. Current exposure to abacavir, efavirenz, lamivudine, and zidovudine was significantly associated with increased risk of cardiovascular event, with odds ratios ranging from 1.40 to 1.53. Five combinations were significantly associated with increased risk of cardiovascular event, all of which involved lamivudine. One of these-efavirenz, lamivudine, and zidovudine-was the second most commonly used combination and was associated with a risk of cardiovascular event that is 1.60 times that of patients not currently exposed to the combination (odds ratio = 1.60, 95% confidence interval, 1.25-2.04). CONCLUSIONS: In the VA cohort, exposure to both individual drugs and drug combinations was associated with modestly increased risk of a cardiovascular event.


Asunto(s)
Antirretrovirales/efectos adversos , Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Cardiovasculares/epidemiología , Infecciones por VIH/tratamiento farmacológico , Veteranos/estadística & datos numéricos , Adulto , Antirretrovirales/uso terapéutico , Femenino , Infecciones por VIH/epidemiología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estados Unidos/epidemiología
12.
J Gen Virol ; 96(9): 2684-2692, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26296881

RESUMEN

Vaccination remains the most effective tool for control of foot-and-mouth disease both in endemic countries and as an emergency preparedness for new outbreaks. Foot-and-mouth disease vaccines are chemically inactivated virus preparations and the production of new vaccines is critically dependent upon cell culture adaptation of field viruses, which can prove problematic. A major driver of cell culture adaptation is receptor availability. Field isolates of foot-and-mouth disease virus (FMDV) use RGD-dependent integrins as receptors, whereas cell culture adaptation often selects for variants with altered receptor preferences. Previously, two independent sites on the capsid have been identified where mutations are associated with improved cell culture growth. One is a shallow depression formed by the three major structural proteins (VP1-VP3) where mutations create a heparan sulphate (HS)-binding site (the canonical HS-binding site). The other involves residues of VP1 and is located at the fivefold symmetry axis. For some viruses, changes at this site result in HS binding; for others, the receptors are unknown. Here, we report the identification of a novel site on VP2 where mutations resulted in an expanded cell tropism of a vaccine variant of A/IRN/87 (called A - ). Furthermore, we show that introducing the same mutations into a different type A field virus (A/TUR/2/2006) resulted in the same expanded cell culture tropism as the A/IRN/87 A - vaccine variant. These observations add to the evidence for multiple cell attachment mechanisms for FMDV and may be useful for vaccine manufacture when cell culture adaptation proves difficult.


Asunto(s)
Proteínas de la Cápside/metabolismo , Cápside/metabolismo , Virus de la Fiebre Aftosa/fisiología , Fiebre Aftosa/virología , Secuencias de Aminoácidos , Animales , Células CHO , Cápside/química , Proteínas de la Cápside/química , Proteínas de la Cápside/genética , Técnicas de Cultivo de Célula , Cricetinae , Cricetulus , Fiebre Aftosa/metabolismo , Virus de la Fiebre Aftosa/química , Virus de la Fiebre Aftosa/genética , Heparitina Sulfato/metabolismo , Unión Proteica , Receptores Virales/metabolismo , Tropismo Viral
14.
Nicotine Tob Res ; 17(5): 586-91, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25239960

RESUMEN

INTRODUCTION: The health effects of cigarette smoking have been estimated to account for between 6%-8% of U.S. health care expenditures. We estimated Veterans Health Administration (VHA) health care costs attributable to cigarette smoking. METHODS: VHA survey and administrative data provided the number of Veteran enrollees, current and former smoking prevalence, and the cost of 4 types of care for groups defined by age, gender, and region. Cost and smoking status could not be linked at the enrollee level, so we used smoking attributable fractions estimated in sample of U.S. residents where the linkage could be made. RESULTS: The 7.7 million Veterans enrolled in VHA received $40.2 billion in VHA provided health services in 2010. We estimated that $2.7 billion in VHA costs were attributable to the health effects of smoking. This was 7.6% of the $35.3 billion spent on the types of care for which smoking-attributable fractions could be determined. The fraction of inpatient costs that was attributable to smoking (11.4%) was greater than the fraction of ambulatory care cost attributable to smoking (5.3%). More cost was attributable to current smokers ($1.7 billion) than to former smokers ($983 million). CONCLUSIONS: The fraction of VHA costs attributable to smoking is similar to that of other health care systems. Smoking among Veterans is slowly decreasing, but prevalence remains high in Veterans with psychiatric and substance use disorders, and in younger and female Veterans. VHA has adopted a number of smoking cessation programs that have the potential for reducing future smoking-attributable costs.


Asunto(s)
Fumar/economía , Tabaquismo/economía , Adolescente , Adulto , Anciano , Femenino , Costos de la Atención en Salud , Gastos en Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Personal Militar , Prevalencia , Fumar/epidemiología , Cese del Hábito de Fumar/estadística & datos numéricos , Tabaquismo/epidemiología , Estados Unidos , United States Department of Veterans Affairs , Veteranos , Salud de los Veteranos , Adulto Joven
15.
N Engl J Med ; 364(9): 842-51, 2011 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-21366475

RESUMEN

BACKGROUND: Long-acting injectable risperidone, a second-generation antipsychotic agent, may improve adherence to treatment and outcomes in schizophrenia, but it has not been tested in a long-term randomized trial involving patients with unstable disease. METHODS: We randomly assigned patients in the Veterans Affairs (VA) system who had schizophrenia or schizoaffective disorder and who had been hospitalized within the previous 2 years or were at imminent risk for hospitalization to 25 to 50 mg of long-acting injectable risperidone every two weeks or to a psychiatrist's choice of an oral antipsychotic. All patients were followed for up to 2 years. The primary end point was hospitalization in a VA or non-VA psychiatric hospital. Symptoms, quality of life, and functioning were assessed in blinded videoconference interviews. RESULTS: Of 369 participants, 40% were hospitalized at randomization, 55% were hospitalized within the previous 2 years, and 5% were at risk for hospitalization. The rate of hospitalization after randomization was not significantly lower among patients who received long-acting injectable risperidone than among those who received oral antipsychotics (39% after 10.8 months vs. 45% after 11.3 months; hazard ratio, 0.87; 95% confidence interval, 0.63 to 1.20). Psychiatric symptoms, quality of life, scores on the Personal and Social Performance scale of global functioning, and neurologic side effects were not significantly improved with long-acting injectable risperidone as compared with control treatments. Patients who received long-acting injectable risperidone reported more adverse events at the injection site and more extrapyramidal symptoms. CONCLUSIONS: Long-acting injectable risperidone was not superior to a psychiatrist's choice of oral treatment in patients with schizophrenia and schizoaffective disorder who were hospitalized or at high risk for hospitalization, and it was associated with more local injection-site and extrapyramidal adverse effects. (Supported by the VA Cooperative Studies Program and Ortho-McNeil Janssen Scientific Affairs; ClinicalTrials.gov number, NCT00132314.).


Asunto(s)
Antipsicóticos/uso terapéutico , Risperidona/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Administración Oral , Adulto , Antipsicóticos/efectos adversos , Preparaciones de Acción Retardada , Femenino , Estudios de Seguimiento , Hospitalización , Hospitales de Veteranos , Humanos , Inyecciones Intramusculares , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Modelos de Riesgos Proporcionales , Calidad de Vida , Risperidona/efectos adversos
16.
Vet Res ; 44: 46, 2013 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-23822567

RESUMEN

The control of foot-and-mouth disease virus (FMDV) outbreaks in non-endemic countries relies on the rapid detection and removal of infected animals. In this paper we use the observed relationship between the onset of clinical signs and direct contact transmission of FMDV to identify predictors for the onset of clinical signs and identify possible approaches to preclinical screening in the field. Threshold levels for various virological and immunological variables were determined using Receiver Operating Characteristic (ROC) curve analysis and then tested using generalized linear mixed models to determine their ability to predict the onset of clinical signs. In addition, concordance statistics between qualitative real time PCR test results and virus isolation results were evaluated. For the majority of animals (71%), the onset of clinical signs occurred 3-4 days post infection. The onset of clinical signs was associated with high levels of virus in the blood, oropharyngeal fluid and nasal fluid. Virus is first detectable in the oropharyngeal fluid, but detection of virus in the blood and nasal fluid may also be good candidates for preclinical indicators. Detection of virus in the air was also significantly associated with transmission. This study is the first to identify statistically significant indicators of infectiousness for FMDV at defined time periods during disease progression in a natural host species. Identifying factors associated with infectiousness will advance our understanding of transmission mechanisms and refine intra-herd and inter-herd disease transmission models.


Asunto(s)
Enfermedades de los Bovinos/transmisión , Virus de la Fiebre Aftosa/aislamiento & purificación , Fiebre Aftosa/transmisión , Animales , Anticuerpos Antivirales/sangre , Bovinos , Enfermedades de los Bovinos/virología , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria
17.
Med Care ; 50(8): 705-13, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22437618

RESUMEN

BACKGROUND: New patient-centered models of ambulatory care aim to substitute better primary care for preventable acute care within existing primary care practices. This study aims to identify whether mental illness and other characteristics of primary care patients are related to risk for an acute event for an ambulatory care-sensitive condition (ACSC). METHODS: We conducted a 2-year, longitudinal analysis comparing ambulatory care-sensitive admissions and emergency department (ED) visits for a cohort of 18,526 primary care patients followed in 5 veterans affairs (VA) primary care sites. We compared rates, risks, and costs of ACSC-related acute events during a follow-up year for patients with and without mental illness seen during the previous year in primary care. RESULTS: The 12-month rate of ACSC admissions was 31.7 admissions per 1000 patients with mental health diagnoses compared with 21.0 admissions per 1000 patients without (P=0.0009). The ACSC-associated ED visit rate was also significantly higher (P<0.0001). In adjusted analyses controlling for demographics, chronic disease, illness severity, and prior ambulatory care, those with depression or drug use disorders had higher odds of receiving ACSC-related acute care (odds ratio=1.10, 95% confidence interval: 1.03, 1.17 for depression; odds ratio=1.48, 95% confidence interval: 1.05, 1.99 for drug use disorders). Costs per admission and ED visit were similar across patient groups. Higher medication use and lower medication regimen complexity were significantly associated with decreased risk for ACSC events. CONCLUSIONS: Prior mental health diagnoses and medication use were independent risk factors for ACSC-related acute care. These risk factors require focused attention if the full benefits of new primary care models are to be achieved.


Asunto(s)
Servicio de Urgencia en Hospital/economía , Servicio de Urgencia en Hospital/estadística & datos numéricos , Trastornos Mentales/economía , Atención Primaria de Salud/economía , United States Department of Veterans Affairs/estadística & datos numéricos , Adulto , Anciano , Femenino , Gastos en Salud/estadística & datos numéricos , Humanos , Estudios Longitudinales , Masculino , Trastornos Mentales/epidemiología , Persona de Mediana Edad , Admisión del Paciente/estadística & datos numéricos , Factores de Riesgo , Factores Socioeconómicos , Estados Unidos , United States Department of Veterans Affairs/economía
18.
Curr Biol ; 18(9): 661-7, 2008 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-18450449

RESUMEN

Many insects perform high-speed aerial maneuvers in which they navigate through visually complex surrounds. Among insects, hoverflies stand out, with males switching from stationary hovering to high-speed pursuit at extreme angular velocities [1]. In dipterans, 50-60 large interneurons -- the lobula-plate tangential cells (LPTCs) -- detect changes in optic flow experienced during flight [2-5]. It has been predicted that large LPTC receptive fields are a requirement of accurate "matched filters" of optic flow [6]. Whereas many fly taxa have three horizontal system (HS) LPTC neurons in each hemisphere, hoverflies have four [7], possibly reflecting the more sophisticated flight behavior. We here show that the most dorsal hoverfly neuron (HS north [HSN]) is sexually dimorphic, with the male receptive field substantially smaller than in females or in either sex of blowflies. The (hoverfly-specific) HSN equatorial (HSNE) is, however, sexually isomorphic. Using complex optic flow, we show that HSN, despite its smaller receptive field, codes yaw velocity as well as HSNE. Responses to a target moving against a plain or textured background suggest that the male HSN could potentially play a role in target pursuit under some conditions.


Asunto(s)
Dípteros/fisiología , Percepción de Movimiento/fisiología , Neuronas/citología , Lóbulo Óptico de Animales no Mamíferos/citología , Caracteres Sexuales , Animales , Femenino , Vuelo Animal/fisiología , Masculino
19.
N Engl J Med ; 359(7): 677-87, 2008 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-18703470

RESUMEN

BACKGROUND: It has not been clearly established whether percutaneous coronary intervention (PCI) can provide an incremental benefit in quality of life over that provided by optimal medical therapy among patients with chronic coronary artery disease. METHODS: We randomly assigned 2287 patients with stable coronary disease to PCI plus optimal medical therapy or to optimal medical therapy alone. We assessed angina-specific health status (with the use of the Seattle Angina Questionnaire) and overall physical and mental function (with the use of the RAND 36-item health survey [RAND-36]). RESULTS: At baseline, 22% of the patients were free of angina. At 3 months, 53% of the patients in the PCI group and 42% in the medical-therapy group were angina-free (P<0.001). Baseline mean (+/-SD) Seattle Angina Questionnaire scores (which range from 0 to 100, with higher scores indicating better health status) were 66+/-25 for physical limitations, 54+/-32 for angina stability, 69+/-26 for angina frequency, 87+/-16 for treatment satisfaction, and 51+/-25 for quality of life. By 3 months, these scores had increased in the PCI group, as compared with the medical-therapy group, to 76+/-24 versus 72+/-23 for physical limitation (P=0.004), 77+/-28 versus 73+/-27 for angina stability (P=0.002), 85+/-22 versus 80+/-23 for angina frequency (P<0.001), 92+/-12 versus 90+/-14 for treatment satisfaction (P<0.001), and 73+/-22 versus 68+/-23 for quality of life (P<0.001). In general, patients had an incremental benefit from PCI for 6 to 24 months; patients with more severe angina had a greater benefit from PCI. Similar incremental benefits from PCI were seen in some but not all RAND-36 domains. By 36 months, there was no significant difference in health status between the treatment groups. CONCLUSIONS: Among patients with stable angina, both those treated with PCI and those treated with optimal medical therapy alone had marked improvements in health status during follow-up. The PCI group had small, but significant, incremental benefits that disappeared by 36 months. (ClinicalTrials.gov number, NCT00007657.)


Asunto(s)
Angina de Pecho/tratamiento farmacológico , Angina de Pecho/terapia , Angioplastia Coronaria con Balón , Calidad de Vida , Antagonistas Adrenérgicos beta/uso terapéutico , Amlodipino/uso terapéutico , Angina de Pecho/etiología , Angina de Pecho/psicología , Aspirina/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Clopidogrel , Terapia Combinada , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/terapia , Estudios Cruzados , Quimioterapia Combinada , Femenino , Estado de Salud , Humanos , Dinitrato de Isosorbide/uso terapéutico , Masculino , Metoprolol/uso terapéutico , Persona de Mediana Edad , Satisfacción del Paciente , Inhibidores de Agregación Plaquetaria/uso terapéutico , Stents , Encuestas y Cuestionarios , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico , Vasodilatadores/uso terapéutico
20.
J Virol ; 84(18): 9149-60, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20592089

RESUMEN

Three-dimensional (3D) porcine nasal mucosal and tracheal mucosal epithelial cell cultures were developed to analyze foot-and-mouth disease virus (FMDV) interactions with mucosal epithelial cells. The cells in these cultures differentiated and polarized until they closely resemble the epithelial layers seen in vivo. FMDV infected these cultures predominantly from the apical side, primarily by binding to integrin alphav beta6, in an Arg-Gly-Asp (RGD)-dependent manner. However, FMDV replicated only transiently without any visible cytopathic effect (CPE), and infectious progeny virus could be recovered only from the apical side. The infection induced the production of beta interferon (IFN-beta) and the IFN-inducible gene Mx1 mRNA, which coincided with the disappearance of viral RNA and progeny virus. The induction of IFN-beta mRNA correlated with the antiviral activity of the supernatants from both the apical and basolateral compartments. IFN-alpha mRNA was constitutively expressed in nasal mucosal epithelial cells in vitro and in vivo. In addition, FMDV infection induced interleukin 8 (IL-8) protein, granulocyte-macrophage colony-stimulating factor (GM-CSF), and RANTES mRNA in the infected epithelial cells, suggesting that it plays an important role in modulating the immune response.


Asunto(s)
Células Epiteliales/virología , Virus de la Fiebre Aftosa/fisiología , Replicación Viral , Animales , Antígenos de Neoplasias/metabolismo , Quimiocina CCL5/biosíntesis , Efecto Citopatogénico Viral , Femenino , Virus de la Fiebre Aftosa/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/biosíntesis , Integrinas/metabolismo , Interferón-alfa/biosíntesis , Interferón beta/biosíntesis , Interleucina-8/biosíntesis , Masculino , Técnicas de Cultivo de Órganos , ARN Mensajero/biosíntesis , Mucosa Respiratoria/virología , Porcinos , Activación Transcripcional , Acoplamiento Viral
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