Efficiency and Safety of CyberKnife Robotic Radiosurgery in the Multimodal Management of Patients with Acromegaly.

OBJECTIVE: To analyze, in a cohort of acromegalic patients, the results of the efficiency and safety of radiosurgery (CyberKnife), as well as the prognostic factors associated with disease remission. MATERIAL AND METHODS: Observational, retrospective, longitudinal, and analytical study that included acromegalic patients with persistent biochemical activity after initial medical-surgical treatment, who received treatment with CyberKnife radiosurgery. GH and IGF-1 levels at baseline after one year and at the end of follow-up were evaluated. RESULTS: 57 patients were included, with a median follow-up of four years (IQR, 2-7.2 years). The biochemical remission rate was 45.6%, 33.33% achieved biochemical control, and 12.28% attained biochemical cure at the end of follow-up. A progressive and statistically significant decrease was observed in the comparison of the concentrations of IGF-1, IFG-1 x ULN, and baseline GH at one year and at the end of follow-up. Both cavernous sinus invasion and elevated baseline IGF-1 x ULN concentrations were associated with an increased risk of biochemical non-remission. CONCLUSION: Radiosurgery (CyberKnife) is a safe and effective technique in the adjuvant treatment of GH-producing tumors. Elevated levels of IGF x ULN before radiosurgery and invasion of the cavernous sinus by the tumor could be predictors of biochemical non-remission of acromegaly.

Depresión posparto: prevalencia y factores de riesgo asociados en una muestra de población mexicana / Postpartum depression: prevalence and associated risk factors in a sample of the Mexican population

Resumen OBJETIVO: Determinar la prevalencia de depresión posparto en una muestra de población mexicana por medio de la Escala de Edimburgo y los factores de riesgo asociados con su inicio MATERIALES Y MÉTODOS: Estudio observacional, transversal, relacional y analítico efectuado en una muestra de población mexicana atendida entre los meses de marzo a julio del 2022 en cuatro hospitales de segundo y tercer nivel de cuatro entidades de la República Mexicana. Se aplicó la escala de Edimburgo a pacientes en el puerperio. Los datos obtenidos se procesaron con una técnica de regresión logística binaria ajustada para identificar los factores de riesgo más importantes de depresión posparto. RESULTADOS: De una muestra de 717 pacientes a quienes se aplicó la Escala de Edimburgo, 106 resultaron positivas a depresión posparto, lo que da una prevalencia del 14.9%. La edad promedio de las pacientes fue de 26 años (límites de 12 y 46). El estado civil soltera resultó un factor protector de depresión posparto y, en su contraparte, quienes estaban casadas tuvieron cierta predisposición a la depresión posparto. A mayor grado de escolaridad menor predisposición a la depresión posparto. CONCLUSIONES: Los principales factores de riesgo de depresión posparto fueron: el antecedente de trastornos psiquiátricos en la familia, depresión previa, dificultades económicas y ser soltera. Las pacientes pueden cursar con diversos factores de riesgo simultáneos, circunstancia que potencia el riesgo de depresión. Es primordial que el obstetra identifique los factores de riesgo desde el control prenatal, a fin de prevenir que el estado depresivo se agudice durante el puerperio.

Abstract OBJECTIVE: To determine the prevalence of postpartum depression in a Mexican population sample by means of the Edinburgh Scale and the risk factors associated with its onset. MATERIALS AND METHODS: Observational, cross-sectional, relational and analytical study carried out in a sample of Mexican population attended from March to July 2022 in four second and third level hospitals in four Mexican states. The Edinburgh scale was applied to postpartum patients. The data obtained were processed with a binary logistic regression technique adjusted to identify the most important risk factors for postpartum depression. RESULTS: From a sample of 717 patients to whom the Edinburgh Scale was applied, 106 were positive for postpartum depression, giving a prevalence of 14.9%. The average age of the patients was 26 years (range 12 and 46). Unmarried marital status was a protective factor for postpartum depression and, on the other hand, those who were married had a certain predisposition to postpartum depression. The higher the level of schooling the lower the predisposition to postpartum depression. CONCLUSIONS: The main risk factors for postpartum depression were: history of psychiatric disorders in the family, previous depression, economic difficulties and being single. Patients may have several simultaneous risk factors, a circumstance that increases the risk of depression. It is essential for the obstetrician to identify the risk factors from the prenatal check-up, to prevent the depressive state from worsening during the puerperium.

Risk Factors Associated with Mortality among Patients with COVID-19: Analysis of a Cohort of 1213 Patients in a Tertiary Healthcare Center.

The presence of cardio-metabolic and respiratory comorbidities, immunosuppression, and chronic kidney disease have been associated with an increase in mortality from COVID-19. The objective of this study is to establish the risk factors associated with 30-day mortality in a cohort of hospitalized patients with COVID-19. This paper conducts a retrospective and analytical study of patients hospitalized for COVID-19 in a tertiary care center. A Cox proportional hazard analysis was performed to estimate the association of comorbidities with 30-day mortality. A total of 1215 patients with a median age of 59 years were included. In the adjusted Cox proportional hazards regression model, hypothyroidism, D-dimer ≥ 0.8 µg/mL, LHD ≥ 430 IU/L, CRP ≥ 4.83 ng/mL, and triglycerides ≥ 214 mg/dL were associated with an increased risk of death. The presence of a history of hypothyroidism and biomarkers (D-dimer, lactic dehydrogenase, CRP, and triglycerides) were associated with an increase in mortality in the studied cohort.

Differential fetal growth rates mediated by sociodemographic factors in Yucatan, Mexico: an epidemiological study.

BACKGROUND: Fetal growth restriction (FGR) may be related to ethnicity. Additionally, ethnic groups experience adverse socioeconomic circumstances that increase FGR risk. However, the dearth of evidence of the interaction between socioeconomic factors and FGR highlights the need for additional research. OBJECTIVE: To analyze the association between socioeconomic factors and FGR in Maya and non-Maya populations in Yucatan, Mexico. METHODS: A total of 21,320 singleton births in 2017 in Yucatan were analyzed. The student's t-test and the chi-square test were used to compare the means and proportions of maternal and perinatal variables between the FGR group and the birthweight appropriate for gestational age (AGA) group. Path analysis was performed to identify the direct and indirect effects of socioeconomic factors on FGR and mediators between predictors and FGR. RESULTS: The prevalence of FGR at birth was 9.06%; this rate was higher in the Maya population (12.4, 95% CI 11.3-13.5), without differences between socioeconomic levels. Path analysis revealed sociostructural variables (ethnicity and poverty) are reliable predictors of FGR at birth mediated by maternal education (ß = -.152, p < .001) and teenage pregnancy (ß = .065, p = .037). The proposal path model had a good fit index CFI = .968, TLI = .920, RMSEA = .046. CONCLUSION: The prevalence of FGR was higher among Maya women than non-Maya women The socioeconomic conditions associated with FGR at birth were ethnicity, poverty, maternal education, and teenage pregnancy. Maternal education and teenage pregnancy act as mediators between sociostructural variables and FGR at birth.

[Methodology for the elaboration of prognosis studies]. / Metodología para la elaboración de los estudios sobre pronóstico.

Prognostic studies are investigations to estimate the risk or probability of future outcomes in people with established disease. Ideally based on cohort studies where it is established: the time of onset or analysis of the evolution of a disease, the follow-up period for the outcome of interest, the type of outcome and the prognostic factors or markers to investigate. Ultimately, the decision on how to run and analyze forecast studies will depend on their purpose: exploratory, explanatory, or predictive.

Los estudios pronósticos son investigaciones para estimar el riesgo o probabilidad de desenlaces futuros en las personas con una enfermedad establecida. Idealmente deben sustentarse en estudios de cohortes en los que se establece el momento de inicio o de análisis sobre la evolución de una enfermedad, el periodo de seguimiento al desenlace de interés, el tipo de desenlace y los factores o marcadores pronósticos por investigar. Finalmente, la decisión de la forma de ejecutar y analizar los estudios de pronóstico dependerá de su propósito: exploratorio, explicativo o predictivo.

Risk factors associated with thyroid nodular disease in acromegalic patients: A case-cohort study in a tertiary center.

INTRODUCTION: Goiter is very common in patients with acromegaly; its development is correlated to the duration of the disease. Thyroid cells express the IGF-1 receptor and the TSH/IGF-1 interaction has been demonstrated to have a synergistic effect in thyroid cell growth. There is a correlation between IGF-1 levels and the thyroid volume of patients with acromegaly. The aim of this study was to evaluate, in a retrospective case-cohort study of patients with acromegaly, the associated risk factors for thyroid nodules disease in this population. METHODS: This was a case-cohort study matched by age, gender, and growth hormone at diagnosis. Cases consisted of acromegalic patients that developed thyroid nodules during the follow up, and controls consisted in acromegalic patients without thyroid nodules. A Cox proportional hazard estimation was carried out for measure the associated risk factors for thyroid nodules disease in acromegalic patients. A nodular thyroid disease-free survival analysis was estimated using the Kaplan-Meier analysis. RESULTS: We recruited 49 cases and 56 controls. In a multivariate Cox proportional hazard analysis age and IGF-1 ≥ 2.2 x ULN were significantly related with the presence of thyroid nodules [HR of 2.21 (95% CI; 1.15-4.25, p = 0.01)]. Nodularity-free survival rates in patients who had an IGF-1 X ULN ≥ 2.2 was found to be lower in comparison to those who had IGF-1 X ULN < 2.2, according to a Kaplan-Meier survival analysis. CONCLUSIONS: Our findings support that exist more probability to develop thyroid nodular disease in patients with acromegaly that present IGF-1 X ULN ≥ 2.2, suggesting a possible direct effect between the time of exposure to the IGF-1 axis hyperactivity and the genesis of thyroid nodules.

[Statistical methods for effect size analysis]. / Métodos estadísticos para el análisis del tamaño del efecto.

Informing in the studies about the effect size of an intervention or the impact of the factor(s) about an outcome, allows better decision-making for the application of the results in clinical practice. This article presents different methods to analyze the effect size, which can be through direct or indirect statistical methods. Within the direct methods, there's the difference in means between groups and the difference of absolute or relative frequencies. Among the indirect methods, Cohen's "d" family (which are based on standard deviation values), the "r and R2" family, measures of association (e.g. OR, RR, HR), and impact measures (e.g. NNT) are shown. The decision to use any of these methods depends on the objectives of the study and the measuring scale that is used to assess the results, as well as the data distribution. In order to enhance the understanding of the methods described in this article, examples are included, and the need to include level of precision (e.g. confidence intervals) is highlighted, along with the clinical decision thresholds for a better interpretation.

Informar en los estudios sobre el tamaño del efecto de una intervención o del impacto de factor(es) sobre un desenlace, permite tomar mejores decisiones para la aplicación de los resultados a la práctica clínica. En este artículo se presenta la manera de analizar el tamaño del efecto, lo cual puede ser mediante métodos estadísticos directos o indirectos. Dentro de los métodos directos, se encuentra la diferencia de promedios entre grupos y la diferencia de frecuencias absolutas o relativas. Dentro de los métodos indirectos se muestran los índices de la familia de "d" de Cohen (que se basan en valores de desviación estándar), la familia de "r y R2", medidas de asociación (RM, RR, HR) e impacto (NNT). La decisión del uso de cualquiera de los métodos descritos, depende de los objetivos del estudio, la escala de medición usada para evaluar los resultados y la distribución de los datos. Para facilitar la comprensión, se incluyen ejemplos y se resalta la necesidad de incluir los diferentes estadísticos con su nivel de precisión (ej. intervalos de confianza), junto con los umbrales clínicos de decisión, a fin de mejorar su interpretación.

[Risk, association, and impact measures in clinical research studies. How to interpret them for their application in medical care]. / Medidas de riesgo, asociación e impacto en los estudios de investigación clínica. Cómo interpretarlas para su aplicación en la atención médica.

The practice of evidence-based medicine includes the critical analysis of clinical research studies, and, within it, the interpretation of the results reported. In addition, to statistical data, there are estimators that can help clinicians transfer research findings to routine clinical practice. These estimators are measures of risk, association, and impact. Risk measures report current uncertainty or probability (prevalence of a disease, sensitivity, specificity) or for future events (cumulative incidence, incidence density). Measures of association are related to the identification of the risk in order to determine whether certain factors increase or decrease the probability of development of a disease (relative risk, odds ratio, hazard ratio). While measures of impact allow, among other things, to estimate the effect of a treatment (relative risk reduction, absolute risk reduction, number needed to treat). In this review, each of these estimators is described, defined, and presented with examples.

Parte del ejercicio de la medicina basada en evidencia incluye el análisis crítico de los estudios de investigación clínica y dentro de este, la interpretación de los resultados presentados. Además de los datos estadísticos, existen estimadores que pueden ayudar a los clínicos a trasladar los hallazgos de las investigaciones a la práctica clínica habitual. Estos estimadores son las medidas de riesgo, asociación e impacto. Las medidas de riesgo informan sobre la incertidumbre o probabilidad en el presente (prevalencia de una enfermedad, sensibilidad, especificidad) o para eventos futuros (incidencia acumulada, densidad de incidencia). Las medidas de asociación se relacionan con la identificación del riesgo para determinar si ciertos factores aumentan o disminuyen la probabilidad del desarrollo de una enfermedad (riesgo relativo, razón de momios, cociente de riesgo). Mientras que las medidas de impacto permiten, entre otros, estimar el efecto de un tratamiento (reducción del riesgo relativo, reducción del riesgo absoluto, número necesario por tratar). En esta revisión se describen, definen y presentan ejemplos de cada uno de estos estimadores.

[Biases in diagnostic test studies: impact on estimating sensitivity and specificity]. / Sesgos en los estudios de pruebas de diagnóstico: implicación en la estimación de la sensibilidad y especificidad.

Diagnostic tests make it possible to determine whether a person has a disease or not. Before incorporating a new diagnostic test in the clinical setting, it is necessary to define its validity through its indicators of performance, sensitivity, and specificity. In these studies, like in any research, the results might not be reliable when there are biases during their execution. This article entails the discussion about the biases in diagnostic test studies that may cause inaccuracy in sensitivity and specificity. The main biases that affect the validity of these studies are: incorporation bias, partial and/or differential verification bias, an imperfect reference standard, a limited spectrum of the disease, and the ambiguous results of the test to be validated. In addition, examples of how these biases impact on the results of sensitivity and specificity are given in this paper.

Las pruebas de diagnóstico permiten determinar si una persona tiene o no una enfermedad. Para incorporar una nueva prueba de diagnóstico en el ámbito clínico primero es necesario definir su validez a través de sus indicadores de desempeño, sensibilidad y especificidad. Como en cualquier investigación, en este tipo de estudios es posible que los resultados no sean confiables cuando hay sesgos durante su ejecución. En este artículo se discuten los sesgos en estudios de prueba diagnóstica que pueden ocasionar que la sensibilidad y especificidad no sean correctas. Los principales sesgos que afectan la validez en estos estudios son el sesgo de incorporación, la verificación parcial o diferencial, un estándar de oro imperfecto, un espectro limitado de la enfermedad y los resultados ambiguos de la prueba por validar. Además, en este artículo se dan ejemplos de cómo impactan estos sesgos en la sensibilidad y especificidad.

Systematic review and meta-analysis as a support tools for research and clinical practice.

Systematic reviews are secondary investigations that compile published results that have been obtained from studies involving human subjects. Meta-analysis is the term used to describe the carrying out of statistical analysis of the combination of the results of two or more original studies, which had to be selected from a systematic review. In this way, a meta-analysis cannot exist without a systematic review. Systematic reviews arise due to the exponential increase in the information; to provide all health personnel with a study that critically analyzes the results and discriminates those that may be useful in clinical practice. Systematic reviews are one of the fundamental tools in evidence-based medicine, in which two of the main steps refer to both the search and the critical analysis of the studies, which shall support medical decisions on aspects that are mainly related to diagnosis, treatment, or prognosis. On the other hand, systematic reviews have been essential for some time now when developing evidence-based clinical practice guidelines and they can be used to make decisions on health policies. The methodology for performing and interpreting systematic reviews and meta-analysis is described in this article.

Las revisiones sistemáticas son investigaciones secundarias que compilan los resultados publicados obtenidos a partir de estudios en seres humanos. El término metaanálisis es utilizado para describir el análisis estadístico de la combinación de los resultados de dos o más estudios originales, los cuales debieron ser seleccionados a partir de una revisión sistemática. De esta forma, no puede haber metaanálisis sin una revisión sistemática. Las revisiones sistemáticas surgen debido al incremento exponencial de la información, para facilitar un estudio que analice críticamente los resultados y discrimine los que puedan ser útiles en la práctica clínica. Las revisiones sistemáticas son una de las herramientas fundamentales en la medicina basada en evidencia, en la cual dos de los pasos principales se refieren a la búsqueda y lectura crítica de los estudios, que apoyarán las decisiones médicas sobre aspectos relacionados principalmente con el diagnóstico, tratamiento o pronóstico. Por otro lado, desde hace tiempo, las revisiones sistemáticas son imprescindibles al elaborar guías de práctica clínica basadas en evidencia y pueden ser utilizadas para tomar decisiones en políticas de salud. En este artículo se describe la metodología para la realización e interpretación de revisiones sistemáticas y metaanálisis.

Neurological repercussions of changes in cerebral blood flow in neonates undergoing cardiovascular surgery.

INTRODUCTION: Surgery for congenital heart disease can generate cerebral perfusion-associated alterations with neurological repercussions. OBJECTIVE: To analyze the relationship of peri-surgical cerebrovascular resistance index (RI) with mediate neurological functions after congenital heart disease surgery. METHOD: Prospective cohort study of 34 neonates in whom basilar artery RI, serum oxygen, carbon dioxide and lactate levels were determined before and after palliative or corrective procedures. We related pre-surgical RI with post-surgical ability to initiate the enteral route or to restore unassisted spontaneous breathing. RESULTS: Three groups were formed: 79 neonates with high RI (> 0.73), 73 with normal RI (0.63 to 0.73) and eight with low RI (< 0.63). In the former group, high RI persisted in the postoperative period, with persistent hyperlactatemia and hypoxia; in 86 %, the enteral route could not be initiated, and neither could assisted ventilation be withdrawn. In the second group, RI remained within normal values. In the third group, although RI, serum lactate and arterial oxygen pressure tended to normalize, 71 % had severe neurological damage. CONCLUSIONS: RI changes were common, although neurological damage appears to occur more commonly when RI remains high, possibly associated with low cerebral blood flow.

INTRODUCCIÓN: La cirugía de cardiopatías congénitas puede generar alteraciones perfusorias cerebrales con repercusión neurológica. OBJETIVO: Analizar la relación del índice de resistencia (IR) vascular cerebral periquirúrgico con funciones neurológicas mediatas posteriores a cirugía de cardiopatía congénita. MÉTODO: Estudio de cohorte prospectivo de 34 neonatos en quienes se determinó IR de la arteria basilar, niveles séricos de oxígeno, dióxido de carbono y lactato, antes y después de procedimientos paliativos o correctivos. Relacionamos el IR prequirúrgico con la capacidad posquirúrgica para iniciar la vía enteral o restablecer la respiración espontánea no asistida. RESULTADOS: Se integraron tres grupos: 79 neonatos con IR alto > 0.73, 73 con IR normal de 0.63 a 0.73 y ocho con IR bajo < 0.63. En los primeros persistió IR elevado en el posquirúrgico, con hiperlactatemia e hipoxia persistentes; en 86 % no se logró iniciar la vía enteral ni retirar la ventilación asistida. En los segundos, el IR se mantuvo en valores normales. En los terceros, si bien el IR, el lactato sérico y la presión arterial de oxígeno tendieron a normalizarse, 71 % presentó daño neurológico grave. CONCLUSIONES: Los cambios en el IR fueron frecuentes, aunque el daño neurológico parece presentarse más cuando el IR se mantiene alto, posiblemente asociado con flujos cerebrales bajos.

Repercusión neurológica por cambios en el flujo sanguíneo cerebral en neonatos sometidos a cirugía cardiovascular / Neurological repercussions of changes in cerebral blood flow in neonates undergoing cardiovascular surgery

Resumen Introducción: La cirugía de cardiopatías congénitas puede generar alteraciones perfusorias cerebrales con repercusión neurológica. Objetivo: Analizar la relación del índice de resistencia (IR) vascular cerebral periquirúrgico con funciones neurológicas mediatas posteriores a cirugía de cardiopatía congénita. Método: Estudio de cohorte prospectivo de 34 neonatos en quienes se determinó IR de la arteria basilar, niveles séricos de oxígeno, dióxido de carbono y lactato, antes y después de procedimientos paliativos o correctivos. Relacionamos el IR prequirúrgico con la capacidad posquirúrgica para iniciar la vía enteral o restablecer la respiración espontánea no asistida. Resultados: Se integraron tres grupos: 17 neonatos con IR alto > 0.73, cinco con IR normal de 0.63 a 0.73 y seis con IR bajo < 0.63. En los primeros persistió IR alto en el posquirúrgico, con hiperlactatemia e hipoxia persistentes; en 86 % no se logró iniciar la vía enteral ni retirar la ventilación asistida. En los segundos, el IR se mantuvo en valores normales. En los terceros, si bien el IR, el lactato sérico y la presión arterial de oxígeno tendieron a normalizarse, 71 % presentó daño neurológico grave. Conclusiones: Los cambios en el IR fueron frecuentes, aunque el daño neurológico parece presentarse más cuando el IR se mantiene alto, posiblemente asociado a flujos cerebrales bajos.

Abstract Introduction: Surgery for congenital heart disease can generate cerebral perfusion-associated alterations with neurological repercussions. Objective: To analyze the relationship of peri-surgical cerebrovascular resistance index (RI) with mediate neurological functions after congenital heart disease surgery. Method: Prospective cohort study of 34 neonates in whom basilar artery RI, serum oxygen, carbon dioxide and lactate levels were determined before and after palliative or corrective procedures. We related pre-surgical RI with post-surgical ability to initiate the enteral route or to restore unassisted spontaneous breathing. Results: Three groups were formed: 17 neonates with high RI (> 0.73), five with normal RI (0.63-0.73) and six with low RI (< 0.63). In the former group, high RI persisted in the postoperative period, with persistent hyperlactatemia and hypoxia; in 86%, the enteral route could not be initiated, and neither could assisted ventilation be withdrawn. In the second group, IR remained within normal values. In the third group, although RI, serum lactate and arterial oxygen pressure tended to normalize, 71% had severe neurological damage. Conclusions: RI changes were common, although neurological damage appears to occur more commonly when RI remains high, possibly associated with low cerebral blood flow.

Information and Communication Technology, Mobile Devices, and Medical Education.

Information and communication technologies (ICT) are practical and highly available tools. In medical education, ICTs allow physicians to update their knowledge and remember the necessary information within reach of current mobile devices. ICTs as preparation tools for medical education have not been reported for medical students in Mexico. To assess the use of mobile devices as ICTs with medical education purposes, we distributed a questionnaire through an online survey management system to all the medical students (n = 180) from a private university in Mexico City, 100% agreed to participate. We developed a questionnaire based on previous surveys and adapted it to our university. All participants reported possession of an electronic mobile device, and 95% used it regularly for learning purposes. Regardless of the school year, the most frequent usage given to these devices was the search and reading of medical articles, the use of medical calculators, and taking notes. As the levels in career advances, there was a reduction in the use of electronic devices. According to the students, the main barriers towards using mobile devices for learning purposes were both the lack of access to the Internet and permission from the professor to use them. Most medical students use mobile devices for learning purposes, but usage changes during their education. It is convenient to encourage the use of mobile devices and the development of ICT skills as tools for educational purposes rather than banning their use in schools and hospitals.

Non-Hodgkin Lymphoma Epidemiology in Children From 2 Socioeconomic Regions in Mexico: 20-Year Registry (1996-2015).

PURPOSE: We analyzed the epidemiologic characteristics of different types of non-Hodgkin Lymphoma (NHL), excluding Burkitt Lymphoma, in 2 Mexican regions with different socioeconomic status. MATERIALS AND METHODS: In this surveillance study, we analyzed the incidence rates (cases per million children/year) of different types of NHL according to the ICCC3, registered in 1996-2015, from 2 different socioeconomic regions in Mexico: central and southern, with higher and lower status, respectively. RESULTS: The principal NHL subgroups were precursor (IIb1), mature B cell (IIb2), mature T/NK cell, and no other specification (NOS; 42.3%, 15.8%, 14.1%, and 27.8%, respectively). In both regions, the overall incidence rates were similar (central=5.3, 95% confidence interval [CI], 4.6-6.1 vs. southern=6.3, 95% CI, 4.6-8.4); also, there were no differences by types (precursor cell LNH, 2.3 vs. 2.5; mature B cell, 0.9 vs. 0.8; mature T/NK cells, 0.8 vs. 0.8; and NOS, 1.4 vs. 2.3). In both regions, a decreasing trend was found (central= -0.17%, 95% CI, -0.03 to -0.3, P=0.04; southern= -0.32%, 95% CI, -0.07 to -0.57, P=0.02), with major reduction of NHL NOS from 1996 to 2000. In both regions, men predominated (2.1:1). CONCLUSIONS: Socioeconomic status did not influence the incidence rates of NHL. In this study, we found a reduction of NHL NOS, possibly due to better typing.

[Phases to determine the clinical utility of diagnostic tests]. / Fases para determinar la utilidad clínica de las pruebas diagnósticas.

In general, diagnostic tests are the necessary tools to determine the presence or absence of illness, but they can be useful also for excluding other differential conditions, assessing severity, establishing specific treatments, and estimating possible prognosis results. In order to determine how much a new diagnostic test can contribute in the clinical setting, studies with different research designs and populations are required. Since it might be complex to understand the development process of a diagnostic test based on its initial stages, this article synthesizes and gives examples of the four phases that have been proposed to define this process. The goals of these four phases are: phase I, establishing reference values; phase II, analyzing the validity of the test; phase III, the impact of its incorporation in diagnostic-therapeutic plans; and phase IV, a long-term assessment after incorporating the diagnostic test.

Generalmente, las pruebas de diagnóstico son las herramientas necesarias para determinar la presencia o no de enfermedad, pero también pueden ser útiles para la exclusión de otras entidades diferenciales, evaluar la gravedad, establecer tratamientos específicos y estimar posibles resultados pronóstico. Para determinar cuánto puede contribuir una nueva prueba de diagnóstico en el ámbito clínico, se requieren estudios con diseños de investigación y poblaciones diferentes. Dado que puede resultar complejo entender el desarrollo de una prueba diagnóstica a partir de sus fases iniciales, en este artículo se sintetizan y se proporcionan ejemplos de las cuatro fases que se han propuesto para definir este proceso. Las metas de estas etapas son las siguientes: fase I, establecimiento de valores de referencia; fase II, análisis de la validez de la prueba; fase III, impacto de su incorporación en el plan diagnóstico; fase IV, evaluación a largo plazo de la incorporación de las prueba diagnóstica.

Accuracy of the 13C-glucose breath test to identify insulin resistance in non-diabetic adults.

AIMS: To assess the validity of the 13C-glucose breath test (13C-GBT) to identify insulin resistance (IR) in non-diabetic individuals, using hyperinsulinemic-euglycemic clamps as gold standard. This validity was compared with that of other IR surrogates. METHODOLOGY: Non-diabetic adults were studied in a cross-sectional design. In a first appointment, oral glucose tolerance tests were conducted simultaneously with 13C-GBTs. Oral 75 g glucose dissolved in 150 ml water, followed by 1.5 mg/Kg body weight U-13C-glucose dissolved in 50 ml water, was administered. Breath and blood samples were collected at baseline and at 30-min intervals. The percentages of glucose-oxidized dose at given periods were calculated. Clamps were conducted a week later. A clamp-derived M value ≤ 6.0 mg/kg*min was used as cut-off. ROC curves were constructed for 13C-GBT, fasting insulin, HOMA, and ISI-composite. RESULTS: Thirty-eight subjects completed the study protocol. The correlation coefficient between the 13C-GBT derived glucose-oxidized dose at 180 min and M values was 0.524 (p = 0.001). The optimal value to identify IR with the 13C-GBT was 4.23% (AUC 0.81; 95CI 0.66, 0.96; accuracy 0.82, 95CI 0.66, 0.92). The 13C-GBT sensitivity (0.88) was higher than HOMA and fasting insulin sensitivities (0.83 and 0.75 respectively), while their specificities were comparable (0.71, 0.71, and 0.79, respectively). The sensitivity of ISI-C was higher (0.92) than that of the 13C-GBT, but its specificity was poor (0.36). The accuracy of the 13C-GBT was superior to that of the other studied surrogates. CONCLUSIONS: The 13C-GBT is a valid and accurate method to detect IR in non-diabetic adults. Therefore, it is potentially useful in clinical and community settings.

[Bayesian analysis. Basic and practical concepts for its interpretation and use]. / Análisis bayesiano. Conceptos básicos y prácticos para su interpretación y uso.

Bayesian statistics is based on subjective probability. It works with evidence updating considering the knowledge acquired prior to an investigation, plus the evidence obtained thereof. Results' interpretation requires for the hypotheses to be tested to be specified and their a priori probability to be estimated before the study. Study evidence is measured with the Bayes factor (compatibility ratio of the data under the proposed hypotheses). The conjunction of hypotheses a priori probabilities with the Bayes factor allows calculating the a posteriori probability of each one of them. The hypothesis with the highest degree of certainty at its update is the one that is accepted for decision making. In this review, three examples of hypothesis to be tested are shown: difference of means, correlation and association.

La estadística bayesiana se basa en la probabilidad subjetiva, trabaja con la actualización de la evidencia considerando los conocimientos adquiridos previos a una investigación, más la evidencia obtenida con esta. La interpretación de los resultados requiere la especificación de las hipótesis por contrastar y su probabilidad a priori antes del estudio. La evidencia del estudio se mide con el factor Bayes (razón de la compatibilidad de los datos bajo las hipótesis propuestas). La conjunción de las probabilidades a priori de las hipótesis con el factor Bayes permite calcular la probabilidad a posteriori de cada una. La hipótesis con mayor grado de certidumbre en su actualización es la aceptada para la toma de la decisión. En esta revisión se muestran tres ejemplos de hipótesis por contrastar: diferencia de promedios, correlación y asociación.

Importancia del "diagnóstico temprano" en los niños con cáncer para mejorar el pronóstico: concepto con poco sustento científico.

La mortalidad por cáncer en niños mexicanos no ha disminuido a los niveles informados en países desarrollados. Una explicación frecuentemente declarada es el alto porcentaje (57.3 %) de pacientes diagnosticados en estadios avanzados (III/IV), atribuible a errores en la sospecha o en la metodología empleada, consideración dudosa si se toma en cuenta que el tiempo de diagnóstico y la proporción de estadios avanzados en México son semejantes a los de países desarrollados. En la mayoría de los niños con cáncer, los días transcurridos desde el primer síntoma a momento del diagnóstico oncológico no correlacionan con el estadio clínico y tampoco con la probabilidad de supervivencia. El éxito en la supervivencia depende en gran medida del tratamiento integral (específico y de la atención a las complicaciones). Esta visión obliga a estrategias dirigidas principalmente a invertir más recursos en opciones terapéuticas eficaces y eficientes, capacitación oncológica integral del equipo de salud (médicos, enfermeras, técnicos), tecnologías diagnósticas, fomento a la colaboración interinstitucional e internacional y apoyo socioeconómico a las familias durante el proceso terapéutico.Cancer mortality in Mexican children has not decreased to the levels reported in developed countries. A commonly proposed explanation is the high percentage (53.7%) of patients diagnosed at advanced stages (III/IV), which is attributed to erroneous assumptions or mistakes in the diagnostic approach ­a questionable consideration taking into account that both time to diagnosis and the proportion of advanced stage cases in Mexico are similar to those in developed countries. In most cancer cases in children, the number of days elapsed from the moment of the first symptom to the cancer diagnosis is not correlated with clinical stage, and neither with the probability of survival. Survival success largely depends on comprehensive treatment (specific and for the care of complications). This view calls for strategies mainly aimed at spending more resources on efficacious and efficient therapeutic strategies, comprehensive oncology training of healthcare personnel (physicians, nurses and technicians), diagnostic technologies, promotion of interinstitutional and international collaboration and socioeconomic support to families during the therapeutic process.

Tratamiento de esguince de tobillo grado II en adultos laboralmente activos: Inmovilización contra vendaje funcional / Grade II ankle sprain treatment in working adults: immobilization versus functional bandage

Resumen Introducción El esguince de tobillo es una patología frecuente y uno de los principales motivos de incapacidad laboral, a pesar de ello, no se cuenta con un tratamiento estandarizado y existe controversia con respecto a la inmovilización o una movilización temprana. Objetivo Determinar el mejor tratamiento para los esguinces de tobillo grado II, ofreciendo un resultado satisfactorio con periodos de incapacidad más cortos. Material y métodos Ensayo clínico-aleatorizado, ciego simple de enero a junio de 2016. Dos grupos: inmovilización y vendaje funcional. Se interrogó dolor inicial y al término del tratamiento con escala de EVA, ambos grupos con mismo manejo analgésico, antiinflamatorio y rehabilitación, se evaluó funcionalidad al mes del inicio del padecimiento con escala de Karlsson. Resultados Todos los pacientes con dolor inicial arriba de 70 (de moderado a severo), sin diferencia en media entre grupos (férula 86.3 ± 9.6 contra vendaje de 86.1 ± 8.5; p = 0.95), ambos con disminución del dolor; el grupo con vendaje obtuvo niveles más bajos (férula media 55.2 ± 15.5 contra vendaje 40.3 ± 12.8, p ≤ 0.001). Grupo con férula 24 (88.9%) al final calificaron su dolor como moderado y tres (11.1%) como leve contra el grupo con vendaje, de los cuales, 17 (73.1%) tuvieron dolor moderado y siete (26.9%) leve (p = 0.15). Conclusión El vendaje funcional es una excelente opción de manejo para esguince de tobillo grado II, ofrece buenos resultados con periodos de incapacidad y costos más reducidos.

Abstract Background The grade II ankle sprain it is one of the most frequent pathologies in the musculoskeletal system and one of the principal motives of laboral inability. Despite the fact this pathology is one of the most common reasons for ER visiting there is not a standard treatment for it, and exist controversy about the immobilization vs. an early mobilization. Objective Determine the best treatment for grade II ankle sprains, offering a satisfactory result with a minor time of labor inability. Material and methods Single-blind randomized controlled clinical trial with two groups immobilization versus functional bandage, both groups with VAS evaluation at the beginning and at the end of treatment, same AINES management and rehabilitation, 30 days after the injury we evaluate the functional outcome with Karlsson score. Results At the beginning all patients report pain over 70 (moderate-severe) without difference in the average of both groups (immobilization 86.3 ± 9.6 versus functional bandage treatment of 86.1 ± 8.5; p = 0.95). Both groups present less pain at the end of the treatment, the bandage group present lower values, (Immobilization average 55.2 ± 15.5 versus functional bandage treatment 40.3 ± 12.8, p ≤ 0.001). In the immobilization group 24 (88.9%) at the end of the treatment had moderate pain and 3 (11.1%) light pain against the functional treatment group where 17 (73.1%) had moderate pain and 7 (26.9%) light (p = 0.15). Conclusion Functional bandage is an excellent treatment option for grade II ankle sprain, offering good results with a lower time of inability and cost.

Use of Distraction to Reduce Pain in Venipunture when a Venoclysis Is Placed.

The use of a venoclysis in hospitalized pediatric patients is a necessity, a procedure perceived by children as painful, so that distraction techniques have been suggested to attenuate this suffering. Evaluating the implementation of a distraction method with an uncontrolled trial with pre and post maneuver evaluation without control group.