Practice Guidelines Website and Systematic Reviews Website

Clinical Practice Guidelines We Can Trust

Released:

March 23, 2011

Type:

Consensus Report

Topic:

Quality and Patient Safety

Activity:

Standards for Developing Trustworthy Clinical Practice Guidelines

Board:

Board on Health Care Services

When treating patients, doctors and other healthcare providers often are faced with difficult decisions and considerable uncertainty. They rely on the scientific literature, in addition to their knowledge, experience, and patient preferences, to inform their decisions. Clinical practice guidelines are statements that include recommendations intended to optimize patient care. They are informed by a systematic review of evidence and an assessment of the benefits and harms of alternative care options. Because of the large number of clinical practice guidelines available, practitioners and other guideline users find it challenging to determine which guidelines are of high quality. If guideline users had a mechanism to immediately identify high quality, trustworthy clinical practice guidelines, their health-related decision making would be improved—potentially improving both health care quality and health outcomes.

The U.S. Congress, through the Medicare Improvements for Patients and Providers Act of 2008, asked the IOM to undertake a study on the best methods used in developing clinical practice guidelines. The IOM developed eight standards for developing rigorous, trustworthy clinical practice guidelines (see the complete list of standards). To properly evaluate the effects of the standards on clinical practice guidelines development and health care quality and outcomes, the IOM encourages the Agency for Health Care Research and Quality to pilot-test the standards and assess their reliability and validity. While there always will be uncertainty in clinical practice, ensuring that clinicians have trustworthy guidelines will bring more evidence to bear on clinician and patient decision making.

Finding What Works in Health Care: Standards for Systematic Reviews

Released:

March 23, 2011

Type:

Consensus Report

Topics:

Biomedical and Health Research, Public Health, Quality and Patient Safety

Activity:

Standards for Systematic Reviews of Comparative Effectiveness Research

Board:

Board on Health Care Services

Healthcare decision makers—including clinicians and other healthcare providers—increasingly turn to systematic reviews for reliable, evidence-based comparisons of health interventions. Systematic reviews identify, select, assess, and synthesize the findings of similar but separate studies. They can help clarify what is known and not known about the potential benefits and harms of drugs, devices, and other healthcare services. But the quality of systematic reviews varies; often the scientific rigor of the collected literature is not scrutinized or there are errors in data extraction and meta-analysis.

In the Medicare Improvement for Patients and Providers Act of 2008, Congress directed the IOM to develop standards for conducting systematic reviews. In this report, the IOM recommends standards for systematic reviews of the comparative effectiveness of medical or surgical interventions (see the list of the standards). The standards are meant to assure objective, transparent, and scientifically valid systematic reviews. The evidence base for how best to conduct systematic reviews is limited, and no set of standards is generally accepted or consistently applied. For example, there is little research on how to manage bias for individuals providing input into the systematic review, or on who should screen and select studies for the review. In developing its standards, the IOM relied on the current methodological evidence and guidance from respected organizations that produce systematic reviews. The IOM's standards address the entire systematic review process, from locating, screening, and selecting studies for the review, to synthesizing the findings (including meta-analysis) and assessing the overall quality of the body of evidence, to producing the final review report.

Ilustration

Ilustration

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Finding What Works in Health Care: Standards for Systematic Reviews

Report Brief

Released:

3/23/2011

Download:

PDF

Finding What Works in Health Care: Standards for Systematic Reviews

Healthcare decision makers in search of reliable information comparing health interventions increasingly turn to systematic reviews for the best summary of the evidence. Systematic reviews identify, select, assess, and synthesize the findings of similar but separate studies and can help clarify what is known and not known about the potential benefits and harms of drugs, devices, and other healthcare services. Systematic reviews can be helpful for clinicians who want to integrate research findings into their daily practices, for patients to make well-informed choices about their own care, and for professional medical societies and other organizations that develop clinical practice guidelines.

In the Medicare Improvement for Patients and Providers Act of 2008, Congress directed the Institute of Medicine (IOM) to develop standards for conducting systematic reviews and to develop standards for clinical practice guidelines, which are evidence-based recommendations for clinicians to use when treating patients. The IOM formed two distinct committees to respond to this charge, and each committee assessed the relevant evidence and considered expert guidance to develop the standards. This report,Finding What Works in Health Care: Standards for Systematic Reviews, recommends standards for systematic reviews of the comparative effectiveness of medical or surgical interventions (see a list of the standards).

Importance of Setting Standards for Systematic Reviews

The quality of systematic reviews is variable. Too often, the scientific rigor of the collected literature is not scrutinized or there are errors in data extraction and meta-analysis. Reporting biases present the greatest obstacle to collecting all relevant information on the effectiveness of an intervention. Research is important to individual decision making, whether it reveals benefits, harms, or lack of effectiveness of a health intervention. Thus, the systematic review should identify all of the studies—and all of the relevant data from the studies—that may pertain to the research question.

The task of identifying relevant research data is challenging. Although hundreds of thousands of research articles are indexed in bibliographic databases each year, a substantial proportion of effectiveness data are never published or are not easy to access. Moreover, it is well documented that published data may not represent all of the findings on an intervention’s effectiveness. Positive findings are more likely to be published than null or negative results.

In many cases, the users cannot determine the quality of a systematic review because the details of the review are so poorly documented. Additionally, many systematic reviews do not focus on questions that are important for real-world healthcare decisions, such as determining whether the benefits of taking a specific medication outweigh the risks.

Standards can improve the quality of systematic reviews, which will minimize the likelihood of clinicians coming to the wrong conclusions and ultimately making the wrong recommendation for treatment. The standards presented in this report—developed by the authoring committee—are meant to ensure objective, transparent, and scientifically valid systematic reviews. The need for establishing standards for systematic reviews was underscored in the health reform legislation The Patient Protection and Affordable Care Act of 2010, which created the nation’s first nonprofit Patient-Centered Outcomes Research Institute (PCORI).

Developing Standards for Systematic Reviews

The committee defines a “standard” as “a process, action, or procedure for performing systematic reviews that is deemed essential to producing scientifically valid, transparent, and reproducible results.”

Systematic reviews of comparative effectiveness research—a type of research that compares different treatment options for the same disease—can be narrow in scope and consist of simple comparisons, such as the effectiveness of one drug versus another. They also can address more complex questions, such as the comparative effectiveness of drugs versus surgery for a specific condition. The committee’s standards apply principally to publicly funded systematic reviews of comparative effectiveness research that focus specifically on treatments.

The evidence base for how best to conduct systematic reviews is limited, and no set of standards is generally accepted or consistently applied. For example, there is little research on how to manage bias for individuals providing input into the systematic review, or on who should screen and select studies for the review. In developing its standards, the committee relied on the current methodological evidence and guidance from respected organizations that produce systematic reviews. The committee’s standards address the entire systematic review process, from locating, screening, and selecting studies for the review, to synthesizing the findings (including meta- analysis) and assessing the overall quality of the body of evidence, to producing the final review report.

The standards are current “best practices”; they are not the last word. All of the recommended standards must be considered provisional, pending better empirical evidence about their scientific validity, feasibility, efficiency, and ultimate usefulness in healthcare decision making. The standards will be especially valuable for systematic reviews of high-stakes clinical questions with broad population impact, where the use of public funds to get the right answer justifies careful attention to the rigor of the systematic review. Individuals involved in systematic reviews should be thoughtful about all of the recommended standards and elements, using their best judgment if resources are inadequate to implement all of them, or if some seem inappropriate for the particular task or question at hand. Transparency in reporting the methods actually used and the reasoning behind the choices are among the most important of the standards recommended by the committee.

Improving the Quality of Systematic Reviews

The committee proposes a framework for improving the quality of the research that supports systematic reviews, including strategies for involving the right people, methods for conducting the systematic review, methods for synthesizing and evaluating evidence, and methods for communicating and using the results. Successful execution and effective use of a systematic review requires improving the science supporting the steps in the systematic review process.

In addition, the committee finds that the environment surrounding the development of systematic reviews lacks adequate funding and coordination—both of which are needed to conduct high-quality systematic reviews. Many organizations conduct systematic reviews, but typically they do not work together. The committee emphasizes the need for greater collaboration among stakeholder groups, including PCORI, government agencies, medical professional societies, researchers, and patient interest groups. Together, these groups have the potential to improve the rigor and transparency of systematic reviews, encourage standardization of methods and processes, set priorities for selection of clinical topics of interest to clinicians and patients, reduce unintentional duplication of efforts, and more effectively manage conflicts of interest.

Recommendations

The committee recommends that PCORI provide oversight and encourage coordination among Department of Health and Human Services (HHS) agencies to improve the research base and support the environment for systematic reviews. Improved coordination should include:

• Developing training programs for researchers, users, consumers, and other stakeholders to encourage more effective and inclusive contributions to systematic reviews of comparative effectiveness research;
• Systematically supporting research that advances the methods for designing and conducting systematic reviews of comparative effectiveness research;
• Supporting research to improve the communication and use of systematic reviews of comparative effectiveness research in clinical decision making;
• Developing effective coordination and collaboration between U.S. and international partners;
• Developing a process to ensure that standards for systematic reviews of comparative effectiveness research are regularly updated to reflect current best practice; and
• Using systematic reviews to inform priorities and methods for primary comparative effectiveness research.

Conclusion

Systematic reviews should be used to inform healthcare decision makers about what is known and not known about the effectiveness of health interventions. Patients expect that their doctors and other healthcare providers know what type of treatment to recommend. Yet the reality is that the evidence that informs current healthcare decisions often is incomplete and may be biased, and there are no standards in place to ensure that systematic reviews of the evidence are objective, transparent, and scientifically valid. Better-quality systematic reviews have the potential to improve the decisions made by clinicians, to better inform patient choice, and to provide a more trustworthy basis for decisions by payers and policy makers.

Report Brief for Practice Guidelines

Report at a Glance

Report Brief

Released:

3/23/2011

Download:

PDF

Clinical Practice Guidelines We Can Trust

Healthcare providers often are faced with difficult decisions and considerable uncertainty when treating patients. They rely on the scientific literature, in addition to their knowledge, skills, experience, and patient preferences, to inform their decisions. Clinical practice guidelines are statements that include recommendations intended to optimize patient care that are informed by a systematic review of evidence and an assessment of the benefits and harms of alternative care options. Rather than dictating a one-size-fits-all approach to patient care, clinical practice guidelines offer an evaluation of the quality of the relevant scientific literature and an assessment of the likely benefits and harms of a particular treatment. This information enables healthcare providers to proceed accordingly, selecting the best care for a unique patient based on his or her preferences.

The U.S. Congress, through the Medicare Improvements for Patients and Providers Act of 2008, asked the Institute of Medicine (IOM) to undertake a study on the best methods used in developing clinical practice guidelines. To ensure that organizations developing such guidelines have information on approaches that are objective, scientifically valid, and consistent, the IOM formed an expert committee. The committee developed eight standards for developing rigorous, trustworthy clinical practice guidelines.

Developing Trustworthy Guidelines

The Guidelines International Network database currently contains more than 3,700 clinical practice guidelines from 39 countries. Additionally, there are nearly 2,700 guidelines in the National Guidelines Clearinghouse (NGC), part of the Agency for Healthcare Research and Quality (AHRQ). Because of the large number of clinical practice guidelines available, guideline users, including practitioners, find it challenging to determine which guidelines are of high quality. If guideline users had a mechanism to immediately identify high quality, trustworthy clinical practice guidelines, their health-related decision making would be improved, potentially resulting in enhanced health care quality and outcomes. Likewise, a set of standards for trustworthy clinical guidelines would help developers create such guidelines, which, in turn, has the potential to improve healthcare decision making and health care quality and outcomes.

Most guidelines used today suffer from shortcomings in development. Dubious trust in guidelines is the result of many factors, including failure to represent a variety of disciplines in guideline development groups, lack of transparency in how recommendations are derived and rated, and omission of a thorough external review process. To be trustworthy, clinical practice guidelines should:

• Be based on a systematic review of the existing evidence;
• Be developed by a knowledgeable, multidisciplinary panel of experts and representatives from key affected groups;
• Consider important patient subgroups and patient preferences, as appropriate;
• Be based on an explicit and transparent process that minimizes distortions, biases, and conflicts of interest;
• Provide a clear explanation of the logical relationships between alternative care options and health outcomes, and provide ratings of both the quality of evidence and the strength of recommendations; and
• Be reconsidered and revised as appropriate when important new evidence warrants modifications of recommendations.

Additionally, as reflected in the committee’s standards for developing trustworthy clinical practice guidelines, guideline development groups optimally comprise members without conflict of interest. The committee recognizes that in some circumstances, a guideline development group may not be able to perform its work without members who have conflicts of interest—for example, relevant clinical specialists who receive a substantial portion of their incomes from services pertinent to the guideline. Therefore, the committee specifies that members of the guideline development group who have a conflict of interest should not represent more than a minority of the group.

The committee standards also emphasize that in making guideline recommendations, the guideline development group should provide a summary of relevant available evidence that describes the quality, quantity, and consistency of that aggregate evidence.

Setting Standards for Trustworthy Guidelines

The committee proposes eight standards for developing trustworthy guidelines. These standards reflect the latest literature, expert consensus, and public input. The committee recommends that all guidelines comply with these standards (see Standards document for more detailed information). The standards reflect best practices across the entire guideline development process, including attention to:

• Establishing transparency;
• Management of conflict of interest;
• Guideline development group composition;
• Clinical practice guideline–systematic review intersection;
• Establishing evidence foundations for and rating strength of recommendations;
• Articulation of recommendations;
• External review; and
• Updating.

The committee’s proposed standards have yet to be tested by clinical practice guideline developers and users to determine whether the standards produce unbiased, scientifically valid, and trustworthy clinical practice guidelines, and whether implementation of the clinical practice guidelines based on the committee’s standards improve health outcomes.

Promoting Adoption

To promote adoption of the standards, the committee recommends that the U.S. Department of Health and Human Services (HHS) create a mechanism to identify trustworthy guidelines. Such identification will serve three purposes: promote wider adoption of the IOM standards by developers since there will be an advantage to clinical practice guidelines publicly identified as trustworthy, provide users of clinical practice guidelines with an easy guide to identify guidelines that are trustworthy, and promote adoption of trustworthy clinical practice guidelines.

To affect quality of care and patient outcomes, implementers should ensure that trustworthy guidelines are made available to clinicians and health systems. Therefore, the committee recommends that implementers employ effective, multi-faceted strategies targeting both individuals and healthcare systems to promote adherence to trustworthy clinical practice guidelines. Increased adoption of electronic health records and computer-aided clinical decision support (CDS) will open new opportunities to rapidly promote clinical practice guidelines to healthcare providers and patients. To advance this goal, guideline developers should structure the format, vocabulary, and content of clinical practice guidelines to help ease the implementation of computer-aided CDS by end-users.

Evaluating Trustworthy Guidelines

It is important that the committee’s standards are properly evaluated. The committee encourages AHRQ to direct a portion of its research funds to pilot-test the standards, to assess their reliability and validity, and to evaluate the effects of the standards on clinical practice guideline development and health care quality and outcomes. While AHRQ is not directly involved in clinical practice guideline development, it does play a vital role in disseminating guidelines through its NGC. The committee recommends that AHRQ require the NGC to discontinue the inclusion of guidelines whose development is not sufficiently documented, and to prominently identify guidelines that reflect the committee’s proposed standards for trustworthiness.

Conclusion

Patients rely on healthcare providers for quality care and expect that those providers have the knowledge and expertise to make health-related decisions. Clinical practice guidelines can aid clinicians and patients alike in determining the best treatment options for a particular disease or condition. While there always will be uncertainty in clinical practice, ensuring that clinicians have trustworthy guidelines will bring more evidence to bear on clinician and patient decision making. Trustworthy guidelines hold the promise of improving health care quality and outcomes.

Scrumblr: herramienta 2.0 para el trabajo colaborativo en línea

18 Mar, 2011

Scrumblr: herramienta 2.0 para el trabajo colaborativo en línea

Posted by: Leonardo Montenegro In: Aplicaciones Web|Didáctica de la Lengua|Herramientas 2.0|Lectura y escritura

Scrumblr es una aplicación Web 2.0 ideal para estimular –entre aprendices, compañeros de oficina, colegas, etc.-  el trabajo colaborativo en tiempo real.

Scrumblr simula una pizarra de notas como la mostrada en la figura 1.

Figura 1. Interfaz gráfica de scrumblr. Scrum significa: a crowd of people who are pushing each other (Oxford Dictionary)

Para acceder al demo de scrumblr haga clic en este enlace.

¿Cómo utilizar Scrumblr?

Siga los siguientes pasos:

1. Visite el enlace http://scrumblr.ca/ (Figura 2).

2. Escriba el nombre de la pizarra que desea generar. Por ejemplo, si escribe mi_pizarra será generada una pizarra que podrá acceder a través del enlace  http://scrumblr.ca/mi_pizarra (Figura 2)

Figura 2. Generando una pizarra de notas para situaciones de comunicación colaborativas.

3. Proponga la actividad y el propósito de su pizarra de notas y distribuya -entre los usuarios participantes- el enlace generadohttp://scrumblr.ca/mi_pizarra

La funcionalidad de scrumblr es bastante intuitiva. Siga las instrucciones mencionadas en las figuras 3, 4, 5 y 6.

.

Figura 3. Agregando y editando las notas de texto.

Figura 4. Agregando títulos a la pizarra de notas.

Figura 5. Asignando un nombre a la pizarra de notas.

Figura 6. Agregando puntos de atención a las notas de texto.

Observación

Aunque no parece claro por cuánto tiempo estará disponible el enlace generado las posibilidades educativas y de colaboración en línea son realmente intersantes.

Instalando scrumblr

Esta aplicación es distribuida en forma libre bajo la licencia GPL. Ha sido programada utilizando node.js, WebSockets (socket.io), CSS3 yjQuery bajo la conceptualización de Ali Asaria, fundador de Well.ca un sitio para la comercialización de productos de salud y belleza.

El código fuente puede ser descargado desde este enlace.

Los requerimientos de instalación han sido comentados en el enlace.

Recomendaciones

1. Utilice scrumblr para:

• Estimular el intercambio de ideas.
• Monitorear los avances de proyectos colaborativos y la toma de decisiones en grupos de trabajo.
• Evaluar conceptos y definiciones en contextos de formación en línea.
• Desarrollar actividades relacionadas con el aprendizaje de lenguas. Por ejemplo, la práctica de vocabulario.

2. Compare scrumblr con otras propuestas similares. Por ejemplo, listhings http://listhings.com/

3. Establezca ventajas y desventajas entre las aplicaciones Web 2.0 en contextos educativos.

Adolescentes, tabaco y mentol

Adolescentes, tabaco y mentol

El 65% de los menores de edad que fuman optan por los cigarrillos mentolados, que se han demostrado más adictivos y peligrosos para la salud
El mentol se ha utilizado de forma habitual como aditivo en los cigarrillos para proporcionar frescor. Sin embargo, el Comité Nacional para la Prevención del Tabaquismo pide que se retire de la venta al público este tipo de tabaco. La razón, apoyada por profesionales del sector sanitario de 40 asociaciones profesionales y sociedades científicas, es que esta sustancia, además de potenciar el hábito de fumar, provoca efectos más dañinos en el organismo humano y, más si cabe, cuando se está en pleno desarrollo.

El mentol está asociado a productos para la higiene dental o enjuagues bucales, golosinas y caramelos, medicamentos, pastillas para la tos, cremas para el dolor y lociones para tratar la picazón, entre otras. Se asocia a la menta, a su frescor y a su origen vegetal. Por estos motivos, pocas veces se tiene en cuenta que es un alcohol obtenido de forma sintética a partir de ésta (Menta arvensis) y que puede implicar intoxicación. Es el caso de los cigarrillos mentolados, entendidos como menos nocivos que el tabaco convencional, si bien tienen poco de naturales y mucho de peligrosos, como denuncian desde el Comité Nacional para la Prevención del Tabaquismo (CNPT).
Sustancia adictiva

Según profesionales y especialistas de hasta 40 asociaciones científicas, el mentol que incluyen algunos cigarrillos es todo menos inocuo. Aumenta la proporción libre de nicotina y potencia sus propiedades adictivas, además de ser broncodilatador, por lo que la nicotina penetra de manera más profunda en el árbol pulmonar y se inhalan más sustancias cancerígenas. A la vez, hace el producto menos desagradable en las primeras fases de consumo y enmascara el sabor del tabaco y los primeros signos nocivos.

Un estudio publicado en 2008 en "American Journal of Public Health" ya aseguraba entonces que esta sustancia oculta la sequedad e irritación que causa el humo del tabaco, si bien no se reduce la acción negativa de las sustancias dañinas, como la nicotina. Las cifras apuntaban que el 43,8% de los jóvenes de 12 a 17 años que empezaban a fumar lo hacía con cigarrillos mentolados, frente al 35,6% de los fumadores de 18 a 24 y del 30% con más de 30 años.

Desde la CNPT denuncian también que estos cigarrillos mentolados son más adictivos que otros sin esta sustancia, gustan más a la población más joven, igual que ocurre con los de sabores frutales frecuentes en países latinoamericanos. Por este motivo y para ayudar a retrasar la edad de inicio en este hábito, este comité exhorta al Estado que adopte acciones de control legal sobre la industria del tabaco.

Evidencian que las cajetillas no informan de manera veraz de los componentes de los cigarrillos, ya que solo anuncian el porcentaje de nicotina, alquitrán y monóxido de carbono, pero no de los otros aditivos, al acogerse a interpretaciones poco claras de las leyes del secreto y propiedad industrial. Se registra una situación, al menos, extraña: el tabaco es el único producto de venta legal no sujeto a la Directiva Europea de etiquetado, que obliga a comercializar todos los productos dirigidos al consumo humano, como alimentos, cosméticos o medicamentos, entre otros, con una etiqueta donde estén reflejados todos y cada uno de sus componentes. Para la CNPT, está situación es incomprensible.
¿Evidencia insuficiente o interés económico?

Asesores de la Administración de Alimentos y Medicamentos estadounidense (FDA) aseguran que la evidencia científica disponible es insuficiente para extraer conclusiones sobre la peligrosidad del tabaco mentolado. Aunque no niegan que sea más adictivo, señalan que no se puede determinar que los fumadores tengan un mayor riesgo de sufrir enfermedades relacionadas. No obstante, la FDA no está obligada a seguir las recomendaciones de los expertos de los paneles que la conforman. Un apunte: los cigarrillos mentolados suponen el 30% de más de 83.000 millones de dólares ingresados por la venta de tabaco. Lorillard Inc. y R.J. Reynolds Tobacco Company de Reynolds American Inc. (dos de las industrias más importantes dedicadas a la producción de tabaco) han presentado una demanda para impedir que la FDA considere la opinión de sus expertos en su decisión final.
Otros componentes nocivos

La nicotina es una sustancia adictiva que se absorbe de manera fácil y muy rápida al inhalar o fumar un producto de tabaco. Al agregarse al torrente sanguíneo, esta sustancia estimula las glándulas suprarrenales que, a su vez, aumentan la liberación de adrenalina, una sustancia que estimula el sistema nervioso central. La adrenalina hace incrementar la presión arterial, el ritmo respiratorio y la frecuencia cardiaca. También se libera más glucosa en sangre, pero la nicotina anula la producción de insulina del páncreas.
Aunque altamente adictiva y tóxica, la nicotina es la culpable de provocar cáncer. Los agentes peligrosos señalados como cancerígenos son los componentes que forman parte del humo del tabaco (con monóxido de carbono, alquitrán, acetaldehído, cianuro y amoniaco). El monóxido de carbono incrementa el riesgo de sufrir enfermedad cardiovascular y el alquitrán, cáncer de pulmón, enfisema y trastornos bronquiales.

Igual que sucede con sustancias como la cocaína, la heroína o la marihuana, la nicotina aumenta los niveles de un neurotransmisor (la dopamina) relacionado con la búsqueda del placer del cerebro y el desarrollo de adicciones. En el caso de muchos fumadores, la exposición persistente a la nicotina provoca un consumo compulsivo, aunque conozcan los resultados dañinos que tiene para la salud. Además, el acetaldehído del humo del tabaco incrementa el efecto que tiene la nicotina sobre el cerebro. Lo peor es que los adolescentes son más susceptibles a los efectos de esta sustancia y tienen una mayor probabilidad de desarrollar adicción al tabaco.
CIFRAS ALARMANTES

Si no se revierten las cifras, en 2020 se atribuirán diez millones de fallecimientos a este hábito

El tabaco es una de las principales causas prevenibles de enfermedades crónicas y se estima que cada año mueren por su causa alrededor de cinco millones de personas, unas 55.000 en España. El escenario futuro no se prevé mejor. Los expertos vaticinan que si no se revierten las cifras, en 2020 se atribuirán diez millones de fallecimientos a este hábito. En los países desarrollados es la primera causa de muerte prematura. Los expertos en tabaquismo la consideran una enfermedad pediátrica, ya que la edad de inicio se establece en la adolescencia: los últimos datos aseguran que el 90% de los fumadores dicen haber fumado su primer cigarrillo antes de los 18 años y el 60%, antes de los 14.

En España, la edad de inicio ronda los 13 años (ser hijo de un fumador aumenta la posibilidad de adicción al tabaco), la más temprana de todo el territorio europeo, y un 30% de los jóvenes de nuestro país ya se consideran adictos al tabaco, una cifra que ha aumentado de forma considerable los últimos años. El mayor número de fumadores noveles se concentra entre adolescentes con nivel de estudios bajo y el menor, entre quienes han cursado estudios universitarios.


www.mediczteam.blogspot.com

Cell Phone Exposure May Cause Bone Weakening, Study Suggests

Main Category: Bones / Orthopedics
Article Date: 25 Mar 2011 - 0:00 PDT


Electromagnetic radiation from cellular phones may adversely affect bone strength, suggests a study in the March Journal of Craniofacial Surgery. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.

Men who routinely wear their cell phone on their belt on the right side have reduced bone mineral content (BMC) and bone mineral density (BMD) in the right hip, according to the study by Dr. Fernando D. Sravi of National University of Cuyo, Mendoza, Argentina. He writes, "The different patterns of right-left asymmetry in femoral bone mineral found in mobile cell phone users and nonusers are consistent with a nonthermal effect of electromagnetic radiofrequency waves not previously described."

Carrying Cell Phone on Belt Linked to Lower Hip Bone Density

Dr. Sravi measured BMC and BMD at the left and right hip in two groups of healthy men: 24 men who did not use cell phones and 24 men who carried their cell phone in a belt pouch, on the right side, for at least one year. Measured using a test called dual-energy x-ray absorptiometry, BMC and BMD are standard markers of bone strength.

Average hip BMC and BMD measurements were not significantly different between groups. However, men who did not use cell phones had higher BMC in the right femoral neck (near the top of the thigh bone): a normal left-right difference that was absent in cell phone users. Thus men who wore their cell phones on the right side had a relative reduction in femoral neck BMC in that hip.

The cell phone users also had reduced BMD and BMC at the right trochanter an area at the outside top of the thigh bone, close to where the phone would be worn on the belt. The difference between the left and right trochanters was significantly related to the estimated total hours spent carrying a cell phone.

There are concerns about several potential harmful effects of cellular phones. However, few studies have looked at whether electromagnetic fields emitted by cell phones could affect bone mineralization. With the rapid growth in cell phone use, any significant effect on BMD could have a substantial effect on the osteoporosis rate in the population.

Although small, the new study raises the possibility that long-term exposure to electromagnetic radiation from cell phones could adversely affect bone mineralization. Larger follow-up studies will be needed to confirm or disprove this hypothesis, according to Dr Sravi. He suggests that studies may be warranted in women, who have higher rates of osteoporosis; and children, who would have longer expected lifetime exposure to cell phones.

Source: Lippincott Williams & Wilkins