Social determinants of health and disparate disability accumulation in a cohort of Black, Hispanic, and White patients with multiple sclerosis.

BACKGROUND: Black and Hispanic patients with multiple sclerosis (MS) have been shown to accumulate greater multiple sclerosis-associated disability (MSAD) than White patients. Disparities in social determinants of health (SDOH) among these groups have also been reported. OBJECTIVE: To determine the extent to which associations of race and ethnicity with MSAD may be attributable to differences in SDOH. METHODS: Retrospective chart analysis of patients at an academic MS center grouped by self-identified Black (n = 95), Hispanic (n = 93), and White (n = 98) race/ethnicity. Individual patient addresses were geocoded and matched with neighborhood-level area deprivation index (ADI) and social vulnerability index (SVI). RESULTS: Average Expanded Disability Status Scale (EDSS) scores at last-recorded evaluations of White patients (1.7 ± 2.0) were significantly lower than Black (2.8 ± 2.4, p = 0.001) and Hispanic (2.6 ± 2.6, p = 0.020) patients. Neither Black race nor Hispanic ethnicity was significantly associated with EDSS in multivariable linear regression models that included individual-level SDOH indicators and either ADI or SVI. CONCLUSION: Black race and Hispanic ethnicity are not significantly associated with EDSS in models that include individual and neighborhood-level SDOH indicators. Further research should elucidate mechanisms by which structural inequities affect MS disease course.

Health Disparities in Multiple Sclerosis among Hispanic and Black Populations in the United States.

Multiple sclerosis (MS) is an acquired demyelinating disease of the central nervous system (CNS). Historically, research on MS has focused on White persons with MS. This preponderance of representation has important possible implications for minority populations with MS, from developing effective therapeutic agents to understanding the role of unique constellations of social determinants of health. A growing body of literature involving persons of historically underrepresented races and ethnicities in the field of multiple sclerosis is assembling. Our purpose in this narrative review is to highlight two populations in the United States: Black and Hispanic persons with multiple sclerosis. We will review the current understanding about the patterns of disease presentation, genetic considerations, response to treatment, roles of social determinants of health, and healthcare utilization. In addition, we explore future directions of inquiry as well as practical methods of meeting these challenges.

Benchmarking the Radiation Oncology Alternative Payment Model: Changes in Medicare Reimbursement for 16 Common Radiation Therapy Treatment Courses.

Radiation oncology (RO) has seen declines in Medicare reimbursement (MCR) in the past decade under the current fee-for-service model. Although studies have explored decline in reimbursement at a per-code level, to our knowledge there are no recent studies analyzing changes in MCR over time for common RO treatment courses. By analyzing changes in MCR for common treatment courses, our study had 3 objectives: (1) to provide practitioners and policymakers with estimates of recent reimbursement changes for common treatment courses; (2) to provide an estimate of how reimbursement will change in the future under the current fee-for-service model if current trends continue; and (3) to provide a baseline for treatment episodes in the event that the episode-based Radiation Oncology Alternative Payment Model is eventually implemented. Specifically, we quantified inflation- and utilization-adjusted changes in reimbursement for 16 common radiation therapy (RT) treatment courses from 2010 to 2020. Centers for Medicare & Medicaid Services Physician/Supplier Procedure Summary databases were used to obtain reimbursement for all RO procedures in 2010, 2015, and 2020 for free-standing facilities. Inflation-adjusted average reimbursement (AR) per billing instance was calculated for each Healthcare Common Procedure Coding System code using 2020 dollars. For each year, the billing frequency of each code was multiplied by the AR per code. Results were summed per RT course per year, and AR for RT courses were compared. Sixteen common RO courses for head and neck, breast, prostate, lung, and palliative RT were analyzed. AR decreased for all 16 courses from 2010 to 2020. From 2015 to 2020, the only course that increased in AR was palliative 2-dimensional 10-fraction 30 Gy, which increased by 0.4%. Courses using intensity modulated RT saw the largest AR decline from 2010 to 2020, ranging from 38% to 39%. We report significant declines in reimbursement from 2010 to 2020 for common RO courses, with the largest declines for intensity modulated RT. Policymakers should consider the significant cuts to reimbursement that have already occurred when considering future reimbursement adjustment under the current fee-for-service model or when considering mandatory adoption of a new payment system with further cuts and the negative effect of such cuts on quality and access to care.

Monte Carlo simulations of synchrotron X-ray dose affecting root growth during in vivo tomographic imaging.

Synchrotron X-ray computed tomography (XCT) has been increasingly applied to study the in vivo dynamics of root growth and rhizosphere processes. However, minimizing radiation-induced damage to root growth warrants further investigation. Our objective was to develop a robust approach for modeling and evaluating ways to reduce synchrotron X-ray dose effects on root growth during in vivo imaging. Wheat roots growing in soil were exposed to X-rays during XCT experiments resolved in space (3D) plus time (4D). The dose rate and cumulative absorbed dose in roots were modelled using the Monte Carlo code FLUKA for different experimental conditions of polychromatic and quasi-monochromatic X-ray beam configurations. The most impactful factors affecting damage to roots were incident X-ray energy spectrum, stored current in the accelerator machine, position of the root in the soil, and possibly the number of exposures during the 4D XCT experiments. Our results imply that radiation dose during in vivo imaging of plant roots can be diminished by using monochromatic radiation at the highest energy suitable for a given sample thickness and field of view, and by controlling the rotation axis of off-centered roots to increase attenuation of radiation by the soil matrix.

Decreases in Radiation Oncology Medicare Reimbursement Over Time: Analysis by Billing Code.

PURPOSE: Radiation oncology (RO) has seen declines in Medicare reimbursement (MCR). However, there are no recent studies analyzing the contributions of specific billing codes to overall RO reimbursement. We compared total MCR for specific Healthcare Common Procedure Coding System (HCPCS) codes in 2019 with MCR for those codes in 2010 and 2015, corrected for inflation, to see how the same basket of RO services in 2019 would have been reimbursed in 2010 and 2015 (adjusted MCR). METHODS AND MATERIALS: The Centers for Medicare & Medicaid Services Physician/Supplier Procedure Summary database was used to obtain MCR data for RO HCPCS codes in 2010, 2015, and 2019. For each code, the total allowed charge was divided by the number of submitted claims to calculate the average MCR per claim in 2010, 2015, and 2019. The 2019 billing frequency for each code was then multiplied by the inflation-adjusted average MCR for those codes in 2010 and 2015 to determine what the MCR would have been in 2010 and 2015 using 2019 dollars and utilization rates. Results were compared with actual 2019 MCR to calculate the projected difference. RESULTS: Total inflation-adjusted RO MCR was $2281 million (M), $1991 M, and $1848 M in 2010, 2015, and 2019 respectively. This represents a cut of $433 M (19%) and $143 M (7%) from 2010 and 2015, respectively, to 2019. After utilization adjustment, total reimbursement was $2534 M, $2034 M, and $1848 M for 2010, 2015, and 2019, respectively, representing a cut of $686 M (27%) and $186 M (9%) from 2010 and 2015, respectively, to 2019. Intensity modulated radiation therapy (IMRT) treatment delivery and planning accounted for $917 M (36%), $670 M (33%), and $573 M (31%) of the adjusted MCR in 2010, 2015, and 2019, respectively. CONCLUSIONS: Medicare reimbursement decreased substantially from 2010 to 2019. A decline in IMRT treatment reimbursement was the primary driver of MCR decline. When considering further cuts, policymakers should consider these trends and their consequences for health care quality and access.

Quantitative Analysis of Practice Size Consolidation in Radiation Oncology: A Trend Toward Bigger and Fewer Practices.

PURPOSE: There is evidence of practice consolidation in US health care in recent years. To our knowledge, a detailed quantitative study of recent changes in radiation oncology practice size has not been performed. We aim to evaluate radiation oncology practice size changes between 2012 and 2020 in the United States. MATERIALS AND METHODS: Using the Medicare Physician Compare Database, we identified practices employing radiation oncologists using their taxpayer identification number and individual radiation oncologists using their national provider identifier. We grouped individual radiation oncologists into categories by practice size (which includes the number of physicians of all specialties) and compared the number of radiation oncologists in each category between 2012 and 2020. Further analyses by US geographic census region, single-specialty practice, academic practice, and high- and low-population density areas were performed. RESULTS: Between 2012 and 2020, the total number of practicing radiation oncologists increased by 9%, and the number of practices employing radiation oncologists decreased by 11.5%. The number of radiation oncologists in practices of size 1 to 2, 3 to 9, 10 to 24, and 25 to 49 decreased by 3.7%, 4.7%, 4.9%, and 2%, respectively, and the number of radiation oncologists in practices of size 50 to 99, 100 to 499, and 500+ increased by 1.4%, 2.1%, and 11.8%, respectively (all 500+ practices are multispecialty groups). The increase in practice size was significant in all regions, for single-specialty and multispecialty practices, academic and nonacademic practices, and for practices in high-, middle-, and low-population density areas (P < .05 for all comparisons). The proportion of single-specialty practices has decreased significantly (P < .001), and the proportion of academic practices increased significantly (P = .004). Additionally, the proportion of practices and physicians in high- and low-population density regions remained stable during this period (P > .05). CONCLUSIONS: Our analysis suggests that practice size consolidation has occurred within the US radiation oncology workforce from 2012 to 2020. The impact of this consolidation on quality, cost, and patient access deserves further attention.

Assessment of Racial/Ethnic Disparities in Volumetric MRI Correlates of Clinical Disability in Multiple Sclerosis: A Preliminary Study.

BACKGROUND AND PURPOSE: Although global and regional brain volume has been established as a relevant measure to define and predict multiple sclerosis (MS) severity, characterization of specific trends by race/ethnicity is currently lacking. We aim to (1) characterize racial disparities in disability-specific patterns of brain MRI volumetric measures between Hispanic and Caucasian individuals with MS and (2) explore the relevance of these measures as predictors of clinical disability progression. METHODS: Brain MRI scans from 94 Hispanic and 94 age- and gender-matched Caucasian MS patients were analyzed using automatic and manual segmentation techniques. Select global and regional volume measures were correlated to Expanded Disability Status Scale (EDSS) scores at baseline and subsequent follow-up visits. RESULTS: Hispanic patients had a higher baseline median EDSS score (interquartile range [IQR], 2.0; [1.0-3.5]) compared to Caucasians (median [IQR], 1.0 [.0-2.0]) and an increased risk of requiring ambulatory assistance (hazard ratio [HR], 9.7; 95% confidence interval [CI], 2.8-32.5). Normalized thalamic volume was moderately associated with EDSS scores (rs   = -.42,  P < .001 in Hispanics; rs   = -.32, P  = .002 in Caucasians) and was the best predictor of sustained disability worsening in both racial groups in a time-to-event analysis. CONCLUSIONS: The confounding impact of race on quantitative brain volume measures may affect the interpretation of outcome measures in MS clinical trials.

Statistical physics of interacting proteins: Impact of dataset size and quality assessed in synthetic sequences.

Identifying protein-protein interactions is crucial for a systems-level understanding of the cell. Recently, algorithms based on inverse statistical physics, e.g., direct coupling analysis (DCA), have allowed to use evolutionarily related sequences to address two conceptually related inference tasks: finding pairs of interacting proteins and identifying pairs of residues which form contacts between interacting proteins. Here we address two underlying questions: How are the performances of both inference tasks related? How does performance depend on dataset size and the quality? To this end, we formalize both tasks using Ising models defined over stochastic block models, with individual blocks representing single proteins and interblock couplings protein-protein interactions; controlled synthetic sequence data are generated by Monte Carlo simulations. We show that DCA is able to address both inference tasks accurately when sufficiently large training sets of known interaction partners are available and that an iterative pairing algorithm allows to make predictions even without a training set. Noise in the training data deteriorates performance. In both tasks we find a quadratic scaling relating dataset quality and size that is consistent with noise adding in square-root fashion and signal adding linearly when increasing the dataset. This implies that it is generally good to incorporate more data even if their quality are imperfect, thereby shedding light on the empirically observed performance of DCA applied to natural protein sequences.

Sistemas de información: definiciones, usos y limitantes al caso de la producción ovina colombiana / Information systems: definitions, applications and limiting of the colombian sheep production / Sistemas de informação: definições, usos e limitações para o caso da produção colombiana de ovelhas

Resumen El acceso rápido y eficiente a una información confiable y precisa permite adoptar una posición adecuada a la hora de tomar una decisión para solucionar un problema con un menor costo; la información es por lo tanto una sustancia figurativa, y se pueden nombrar ciertas posturas sobre ella: la posesión, la acumulación, exceso ("sobrecarga"), la desigualdad distributiva ("los que tienen y los que no"), la medición, la "comoditización", y así sucesivamente, antes de entender per se el uso de los sistemas de información. Es incuestionable el hecho de que mucha gente está derivando grandes ventajas de estas nuevas fuentes de conocimiento prestadas por redes y sistemas de información, en el marco de lo que ahora se convenciona llamar el sector cuaternario de la economía. Los datos, información y el conocimiento son eslabones de una cadena cíclica en la que el último eslabón realimenta la cadena, a la vez que el valor del recurso y la aportación e implicación humana son cada vez mayores. El objeto de la presente revisión es aportar al entendimiento de los sistemas de información y su orientación actual como herramienta para la mejora de la competitividad del sector ovino nacional.

Abstract The fast and efficient access to reliable and accurate information allows adopting a suitable position when making a decision to troubleshoot a lower cost; information is thus a figurative substance, and can appoint certain positions on it: possession, accumulation, excess ("overload"), distributive inequality ("the haves and have-nots"), measurement, the "commoditization", and so on, before understanding per se the use of information systems. It is unquestionable that many people are deriving great advantages of these new sources of knowledge borrowed from networks and information systems, as part of what is now called the "quaternary sector of the economy". The data, information and knowledge are links in a cyclic chain where the last link in the chain fed, while the resource value and contribution and human involvement are increasing. The purpose of this review is to provide an understanding of information systems and the current focus as a tool for improving the competitiveness of the Colombian domestic sheep industry.

Resumo O acesso rápido e eficiente às informações confiáveis e precisas permitem adoptar uma posição adequada ao tomar uma decisão para solucionar um custo menor; informação é, portanto, uma substância figurativa, e pode designar certas posições sobre ele: a posse, a acumulação, o excesso ("sobrecarga"), a desigualdade distributiva ("os que têm e os que não têm"), medição, o "commoditization", e assim por diante, antes de compreender per se a utilização de sistemas de informação. É inquestionável que muitas pessoas estão a retirar grandes vantagens destas novas fontes de conhecimento emprestado de redes e sistemas de informação, como parte do que hoje é chamado de conven setor quaternário da economia. Os dados, informação e conhecimento são elos de uma cadeia cíclica, onde o último elo da cadeia alimentados, enquanto o valor de recursos e contribuição e envolvimento humano estão aumentando. O objetivo desta revisão é fornecer uma compreensão de sistemas de informação e o foco atual como uma ferramenta para melhorar a competitividade da indústria ovina doméstica.

Breast radiation therapy guideline implementation in low- and middle-income countries.

Radiation therapy plays a critical role in the management of breast cancer and often is unavailable to patients in low- and middle-income countries (LMCs). There is a need to provide appropriate equipment and to improve the techniques of administration, quality assurance, and use of resources for radiation therapy in LMCs. Although the linear accelerator is the preferred equipment, telecobalt machines may be considered as an acceptable alternative in LMCs. Applying safe and effective treatment also requires well trained staff, support systems, geographic accessibility, and the initiation and completion of treatment without undue delay. In early-stage breast cancer, standard treatment includes the irradiation of the entire breast with an additional boost to the tumor site and should be delivered after treatment planning with at least 2-dimensional imaging. Although postmastectomy radiation therapy (PMRT) has demonstrated local control and overall survival advantages in all patients with axillary lymph node metastases, preference in limited resource settings could be reserved for patients who have >or=4 positive lymph nodes. The long-term risks of cardiac morbidity and mortality require special attention to the volume of heart and lungs exposed. Alternative treatment schedules like hypofractionated radiation and partial breast irradiation currently are investigational. Radiation therapy is an integral component for patients with locally advanced breast cancer after initial systemic treatment and surgery. For patients with distant metastases, radiation is an effective tool for palliation, especially for bone, brain, and soft tissue metastases. The implementation of quality-assurance programs applied to equipment, the planning process, and radiation treatment delivery must be instituted in all radiation therapy centers.

Assessment of heavy metal accumulation in two species of Tillandsia in relation to atmospheric emission sources in Argentina.

The ability of Tillandsia capillaris Ruiz and Pav. f. capillaris and Tillandsia permutata A. Cast. to accumulate heavy metals was evaluated in relation to potential atmospheric emission sources in Argentina. The sampling areas (n=38) were chosen in the province of Córdoba, located in the center of Argentina, and categorized according to land use, anthropogenic activities and/or distance to potential heavy metal emission sources. In each sampling site, pools of 40-50 individuals of each species were made from plants collected along the four cardinal directions. The concentrations of V, Mn, Fe, Co, Ni, Cu, Zn, Pb and Br of these samples were measured by Total Reflection X-Ray Fluorescence (TXRF) analysis with Synchrotron Radiation. Each species was submitted to a cluster analysis in order to discriminate different groups of heavy metals as tracers of natural or anthropogenic sources. A Contamination Factor (CF) was calculated using the concentrations of the elements in each sample compared to their concentrations in the control samples. Finally, the rank coefficients of correlation between the CFs and the categorical variables characteristic of each site (land use and anthropogenic load) were analyzed. A positive correlation was found for T. capillaris between the CFs of V, Mn, Co, Ni, Cu and Zn and the urban-industrial category, whereas the CF values for Zn and Pb were positively correlated with the road category. In T. permutata there was a positive correlation between the CF of Zn and the urban-industrial category and the CF of Pb with the road category. We therefore conclude that T. capillaris is a more efficient metal accumulator in passive biomonitoring studies.

Biological, physical factors in clinical assessment of outcome of cancer therapy.

Complex molecular and cellular biological phenomena influence the response of tumor and normal cell to cytotoxic agents, including irradiation. Innovative 3-D treatment planning and IGRT techniques allow more quantitative optmization of irradiation dose distribution in target volumes and OAR. More detailed reporting on radiation doses is required with incorporation of biological parameters in treatment planning and dose specification. TCP and NTCP models should be validate with actual clinical data. Quality assurance in radiation oncology is mandatory. Because of increasing concerns with health care costs, technology assessment and cost benefit studies should be an integral component of clinical outcome reporting.

Clinical assessment of outcome of prostate cancer (TCP, NTCP).

In the recent past there have been major advances in the management of patients with prostate cancer. New imaging procedures as 3-D CRT and IMRT have played a major role in the tretament of patients with localized prostate cancer. 3-D CRT allows higher doses to be delivered more precisely to the target volume with acceptable organs at risk morbidity. Improved tumor control results in lower incidence of distant metastases and better survival with an enhanced quality of life. This outcome yields a lower cost per treatment of patients over their life time.