Riesgo de recurrencia y factores de riesgo de invasión del cáncer diferenciado de tiroides / Risk of recurrence and risk factors for invasion of differentiated thyroid cancer

Introducción: El cáncer diferenciado de tiroides (CDT) se encuentra representado por el carcinoma papilar y el carcinoma folicular. Comprende la gran mayoría (>90%) de todos los cánceres de tiroides. Objetivos: Estratificar el riesgo de recurrencia inicial de los pacientes con CDT. Relacionar la edad, sexo y tamaño tumoral con el riesgo de recurrencia, invasión capsular, ganglionar, vascular y de tejido peritiroideo. Materiales y métodos: Estratificar el riesgo de recurrencia inicial de los pacientes con CDT. Relacionar la edad, sexo y tamaño tumoral con el riesgo de recurrencia, invasión capsular, ganglionar, vascular y de tejido peritiroideo. Resultados: El 87% fueron del sexo femenino. La edad media fue de 43±14 años. Predominó el riesgo de recurrencia bajo en el 49% de los pacientes, seguido del riesgo intermedio (33%) y riesgo alto (18%). El tamaño tumoral ˃1cm confiere mayor riesgo de ser estratificado como riesgo de recurrencia intermedio/alto (OR 5,7 IC 95% 3,6-9). El sexo masculino representó mayor riesgo de invasión ganglionar (OR 2,8 IC 95% 1,2-6,6); la edad ≥55 años lo fue en la invasión vascular (OR 2,1 IC 95% 1,1-4,1); el tamaño >1cm constituyó un mayor riesgo de manera significativa de invasión capsular (OR 10,5 IC 95% 6,5-17), invasión ganglionar (OR 10,2 IC 95% 3,8-26,9), invasión vascular (OR 30,7 IC 95% 4,2-224) e invasión de tejido peritiroideo (OR 5,2 IC 95% 3,3-8,2). Conclusión: El riesgo de recurrencia inicial más frecuente fue el riesgo bajo. El sexo masculino, la edad ≥55años y el tamaño >1cm constituyen factores de riesgo de invasión a estructuras vecinas.

Introduction: Differentiated thyroid cancer (DTC) is represented by papillary carcinoma and follicular carcinoma. It comprises the vast majority (> 90%) of all thyroid cancers. Objectives: Stratify the risk of initial recurrence of patients with DTC. Relate age, sex, and tumor size to the risk of recurrence, capsular, nodal, vascular, and perithyroid tissue invasion. Materials and methods: Observational, descriptive, retrospective, cross-sectional study with an analytical component. A total of 432 patients with a diagnosis of DTC from Hospital de Clínicas, Instituto de Previsión Social and Instituto Nacional del Cáncer between 2011 and 2015 were included. Results: 87% were female. The mean age was 43 ± 14 years. Low recurrence risk predominated in 49% of patients, followed by intermediate risk (33%) and high risk (18%). Male sex, age ≥55 years and tumor size ˃1cm confer a higher risk of being stratified as intermediate / high recurrence risk, but only size> 1cm was significantly (OR 5.7 95% CI 3.6-9). Male sex represented a higher risk of lymph node invasion (OR 3.1 95% CI 1.4-2.8) and vascular invasion (OR 2.3 95% CI 1.1-4.8); age ≥55 years was in the vascular invasion (OR 2.6 95% CI 1.4-4.9); size> 1cm constituted a significantly higher risk of capsular invasion (OR 10.7 95% CI 6.7-17.3), nodal invasion (OR 10.5 95% CI 4-27.7), vascular invasion (OR 33 95% CI 4.5-244) and invasion of perithyroid tissue (OR 5.1 95% CI 3.2-8.1). Conclusion: The most frequent initial recurrence risk was low risk. Male sex, age ≥55 years, and size> 1cm are risk factors for invasion of neighboring structures.

Quantitative Relationships Between Growth, Differentiation, and Shape That Control Drosophila Eye Development and Its Variation.

The size of organs is critical for their function and often a defining trait of a species. Still, how organs reach a species-specific size or how this size varies during evolution are problems not yet solved. Here, we have investigated the conditions that ensure growth termination, variation of final size and the stability of the process for developmental systems that grow and differentiate simultaneously. Specifically, we present a theoretical model for the development of the Drosophila eye, a system where a wave of differentiation sweeps across a growing primordium. This model, which describes the system in a simplified form, predicts universal relationships linking final eye size and developmental time to a single parameter which integrates genetically-controlled variables, the rates of cell proliferation and differentiation, with geometrical factors. We find that the predictions of the theoretical model show good agreement with previously published experimental results. We also develop a new computational model that recapitulates the process more realistically and find concordance between this model and theory as well, but only when the primordium is circular. However, when the primordium is elliptical both models show discrepancies. We explain this difference by the mechanical interactions between cells, an aspect that is not included in the theoretical model. Globally, our work defines the quantitative relationships between rates of growth and differentiation and organ primordium size that ensure growth termination (and, thereby, specify final eye size) and determine the duration of the process; identifies geometrical dependencies of both size and developmental time; and uncovers potential instabilities of the system which might constraint developmental strategies to evolve eyes of different size.

Psychosocial Correlates of Suicidal Behavior among Adolescents under Confinement Due to the COVID-19 Pandemic in Aguascalientes, Mexico: A Cross-Sectional Population Survey.

Background: Suicide and suicidal behaviors were already a global public health problem, producing preventable injuries and deaths. This issue may worsen due to the COVID-19 pandemic and may differentially affect vulnerable groups in the population, including children, adolescents, and young adults. The current study evaluated the association of affective variables (depression, hopelessness, and anxiety), drug use (alcohol, tobacco, and others), emotional intelligence, and attachment with suicidal behaviors. Methods: A state-wide survey included 8033 students (51% female, 49% male; mean age of 16 years) from science and technology high-schools using a standardized questionnaire that was distributed online. Multinomial logistic regression models tested associations between suicidal behaviors and several covariates. The analyses accommodated the complex structure of the sample. Results: Approximately 21% of all students reported a suicidal behavior (11% with a low-lethality suicide attempt, 6% with self-injuries, and 4% with a high-lethality suicide attempt). Variables associated with higher odds of suicidal behavior included: female sex, depression, hopelessness, anxiety, alcohol and tobacco use, childhood trauma, and having to self-rely as issues affecting attachment, and low self-esteem. Security of attachment was associated with lower odds of suicidal behavior. Conclusions: The complexity of suicidal behavior makes it clear that comprehensive programs need to be implemented.

Polymer-induced microcolony compaction in early biofilms: A computer simulation study.

Microscopic organisms, such as bacteria, have the ability of colonizing surfaces and developing biofilms that can determine diseases and infections. Most bacteria secrete a significant amount of extracellular polymer substances that are relevant for biofilm stabilization and growth. In this work, we apply computer simulation and perform experiments to investigate the impact of polymer size and concentration on early biofilm formation and growth. We observe as bacterial cells formed loose, disorganized clusters whenever the effect of diffusion exceeded that of cell growth and division. Addition of model polymeric molecules induced particle self-assembly and aggregation to form compact clusters in a polymer size- and concentration-dependent fashion. We also find that large polymer size or concentration lead to the development of intriguing stripe-like and dendritic colonies. The results obtained by Brownian dynamic simulation closely resemble the morphologies that we experimentally observe in biofilms of a Pseudomonas Putida strain with added polymers. The analysis of the Brownian dynamic simulation results suggests the existence of a threshold polymer concentration that distinguishes between two growth regimes. Below this threshold, the main force driving polymer-induced compaction is the hindrance of bacterial cell diffusion, while collective effects play a minor role. Above this threshold, especially for large polymers, polymer-induced compaction is a collective phenomenon driven by depletion forces. Well above this concentration threshold, severely limited diffusion drives the formation of filaments and dendritic colonies.

Prevalencia de Cáncer de Tiroides en Centros de Referencia del Paraguay / Prevalence of Thyroid Cancer in Reference Centers of Paraguay

Introducción: El Cáncer de tiroides es la neoplasia maligna más frecuente del sistema endócrino. Durante las últimas décadas se ha observado un aumento de su incidencia de forma progresiva en numerosos países y regiones del mundo. Objetivos: Determinar la prevalencia de Cáncer de tiroides y, los tipos histológicos, en 3 hospitales de referencia en Paraguay. Materiales y métodos: Estudio observacional, descriptivo, retrospectivo, de corte transversal. Se incluyó a todos los pacientes sometidos a tiroidectomía parcial o total en el Hospital de Clínicas, Instituto de Previsión Social e Instituto Nacional del Cáncer, entre los años 2011 y 2015. Resultados: La prevalencia de cáncer de tiroides fue de 23,7% de 1913 pacientes sometidos a tiroidectomía. El 85,7% fueron del sexo femenino. La edad media fue de 43±14 años. El 85,4 % de los pacientes presentó Carcinoma Papilar; el 9,5% Carcinoma Folicular; el 3,1% Carcinoma Medular; el 1,6% Carcinoma Anaplásico y el 0,4% Carcinoma Papilar + Carcinoma Folicular en el mismo paciente. El sexo femenino fue más frecuente en todos los tipos histológicos y, el Carcinoma Medular resultó igual en ambos sexos. La edad media de los pacientes con Carcinoma Papilar fue de 42±13 años, Carcinoma Medular 49±15 años, del Carcinoma Folicular 50±18 años y Carcinoma Anaplásico 69±11 años. El tamaño promedio del Carcinoma Papilar fue de 19±17 mm, del Carcinoma Folicular 53±24 mm, del Carcinoma Medular 40±22 mm, y el Carcinoma Anaplásico 50±35 mm. Conclusión: Aproximadamente 1 de cada 4 pacientes sometidos a tiroidectomía presentó cáncer de tiroides, siendo más frecuente en el sexo femenino y, el Carcinoma Papilar es el tipo histológico más frecuente.

Introduction: Thyroid cancer is the most frequent malignant neoplasm of the endocrine system. During the last decades, an increase in its incidence has been observed progressively in many countries and regions of the world. Objectives: To determine the prevalence of thyroid cancer and its histological types in thyroidectomies carried out in reference hospitals in Paraguay. Materials and methods: Observational, descriptive, retrospective, cross-sectional study. All patients undergoing partial or total thyroidectomy at the Hospital de Clínicas, Instituto de Previsión Social and Instituto Nacional del Cáncer between 2011 and 2015 were included. Results: The prevalence of thyroid cancer was 23.7% of 1913 patients undergoing thyroidectomy. 85.7% were female. The mean age was 43 ± 14 years. 85.4% of the patients presented Papillary Carcinoma; 9.5% Follicular Carcinoma; 3.1% Medullary Carcinoma; 1.6% Anaplastic Carcinoma and 0.4% Papillary Carcinoma + Follicular Carcinoma in the same patient. The mean age of the patients with Papillary Carcinoma was 42 ± 13 years, Medullary Carcinoma 49 ± 15 years, Follicular Carcinoma 50 ± 18 years, and Anaplastic Carcinoma 69 ± 11 years. The average size of Papillary Carcinoma was 19 ± 17 mm, Medullary Carcinoma 40 ± 22 mm, Anaplastic Carcinoma 50 ± 35 mm, and Follicular Carcinoma 53 ± 24 mm. Conclusion: About 1 in 4 patients undergoing thyroidectomy has thyroid cancer, it is more frequent in women, and the most frequent histological type is Papillary Carcinoma.

Validation of Health Behavior and Stages of Change Questionnaire.

BACKGROUND: The transtheoretical model (TTM) has been widely used to promote healthy behaviors in different groups. However, a questionnaire has not yet been developed to evaluate the health behaviors that medical practitioners often consider in individuals with cancer or at a high risk of developing cancer. PURPOSE: The aim of this study was to construct and validate the Health Behavior and Stages of Change Questionnaire (HBSCQ), which is based on the TTM and health recommendations related to risk and factors that protect against cancer. METHODS: Content validity was conducted in two phases (qualitative and quantitative). Item difficulty index, item discrimination index, and discrimination coefficient were obtained based on the classical test theory. Finally, Cronbach's alpha was used. RESULTS: Measure of concordance showed scores considered adequate and excellent. The item discrimination index obtained a rating of "excellent" and suggested the preservation of all items. The discrimination coefficient scores are >0.74. The global internal consistency of the HBSCQ was 0.384. HBSCQ specification between groups of internal consistency for the sample of men was 0.712 and that for the sample of women was 0.378. CONCLUSION/IMPLICATIONS FOR PRACTICE: The HBSCQ represents a proposal for a fast, simple, and innovative screening test, which aims to identify persons who may benefit from interventions to promote health behaviors delimited to the stage of change.

Bacterial flora in the sputum and comorbidity in patients with acute exacerbations of COPD.

OBJECTIVE: To determine in patients admitted with an acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) the association between the isolation of potential pathogens in a conventional sputum culture and comorbidities. PATIENTS AND METHODS: The ESMI study is a multicenter observational study. Patients with AE-COPD admitted to the Internal Medicine departments of 70 hospitals were included. The clinical characteristics, treatments, and comorbidities were gathered. The results of conventional sputum cultures were recorded. RESULTS: A total of 536 patients were included, of which 161 produced valid sputum and a potentially pathogenic microorganism was isolated from 88 subjects (16.4%). The isolation of Pseudomonas aeruginosa (30.7%) was associated with a greater severity of the lung disease (previous admissions [P= 0.026], dyspnea scale [P=0.047], post-broncodilator forced expiratory volume in 1 second (FEV1) [P=0.005], and the BODEx index [P=0.009]); also with higher prevalence of cor pulmonale (P=0.017), heart failure (P=0.048), and cerebrovascular disease (P=0.026). Streptococcus pneumoniae (26.1%) was associated with more comorbidity according to number of diseases (P=0.018); notably, peripheral artery disease (P=0.033), hypertension (P=0.029), dyslipidemia (P=0.039), osteoporosis (P=0.0001), and depression (P=0.005). CONCLUSION: Patients with AE-COPD and P. aeruginosa present higher severity of COPD, while those with S. pneumoniae present greater comorbidity. The potentially pathogenic microorganism obtained in the sputum culture depends on the associated comorbidities.

Relación de la Socialización Organizacional y el Compromiso Organizacional en Trabajadores Mexicanos / Relationship Between Mexican Workers' Organizational Socialization and Commitment

La socialización organizacional es el proceso por el que una persona adquiere competencias laborales en términos de un nivel de comprensión funcional de la organización, consigue el apoyo de sus compañeros de trabajo, y acepta las normas de una organización. El objetivo de la presente investigación fue determinar la relación entre la socialización organizacional y el compromiso organizacional en trabajadores mexicanos. Se analizaron los datos obtenidos de 169 participantes, que fueron evaluados con el Inventario de Socialización Organizacional y el Cuestionario de Compromiso Organizacional. Los resultados mostraron que la socialización organizacional correlacionó positiva y significativamente con el compromiso afectivo y normativo. Se concluyó que la socialización organizacional permite que los trabajadores desarrollen el compromiso con la organización a través de los vínculos afectivos con los compañeros y la creación de un sentido de lealtad hacia la organización.

This research focuses on the relationship between Mexican workers' organizational socialization and compromise. Organizational socialization is a process in which a person acquires labor skills, understands and accepts institutional rules, and gains the support of their co-workers. 169 participants were sampled using the Organizational Socialization Inventory and Organizational Compromise Questionnaire. The results showed that organizational socialization correlated positively and significantly with affective and normative commitment. As a conclusion, organizational socialization allows workers to develop a compromise with the organization through affective links with co-workers and a sense of loyalty to the institution.

Evaluación de un Programa de Intervención para Disminuir el Acoso Escolar y la Conducta Disruptiva / Evaluation of the Effectiveness of an Intervention Program in Reducing Bullying and Disruptive Behavior

Resumen: Existen pocos programas de intervención para disminuir las conductas infantiles de acoso escolar en el aula. El propósito del estudio fue conocer la eficacia de un programa de intervención basado en los principios del Análisis Conductual Aplicado para reducir las conductas infantiles de acoso en el ámbito escolar. El programa está diseñado para entrenar al profesor del grupo en el manejo de ocho técnicas conductuales (i.e., control de estímulos, costo de respuesta, entrenamiento en respuesta alternativa, auto-control de enojo, contingencia grupal, análisis de tareas, monitoreo y moldeamiento). Se entrenó a ocho profesores de tres escuelas primarias públicas para que implementaran el programa durante la jornada escolar. Participaron 223 alumnos, 28 de ellos identificados como acosadores y 28 identificados como víctimas. Se evaluó la conducta de acoso por parte de esos 28 niños y la conducta disruptiva de los 223 estudiantes pre, durante y post tratamiento. Los resultados mostraron que el programa de intervención redujo significativamente el acoso escolar por parte de los niños acosadores. El programa también fue exitoso para reducir las conductas disruptivas de los niños en todo el grupo, especialmente fue efectivo disminuyendo el comportamiento antisocial.

Abstract: There are few intervention programs designed for reducing bullying in the classrooms. The purpose of the study was to determine the effectiveness of an intervention program based on the principles of applied behavior analysis to reduce bullying in the classroom. The program was designed to train elementary school teachers in the application of eight behavioral techniques (i.e., stimuli control, cost of response, reinforcing alternative responses, self-control of anger, group contingencies, task analysis, monitoring, and shaping). Eight teachers from three public schools were trained and they implemented the program during a whole school year. Those teachers had 223 students. From that total 28 were identified as bullies and 28 as victims. The bullying behavior of those 28 children as well as the disruptive behaviors of the 223 students were measured pre, during and post treatment. Results showed that the intervention program was successful in reducing bullying as well as disruptive behaviors. The program was especially effective in reducing antisocial behavior.

COPD patients with and without metabolic syndrome: clinical and functional differences.

Chronic obstructive pulmonary disease (COPD) and the metabolic syndrome (MetS) are considered public health challenges of the 21st century. The coexistence of MetS in COPD patients and any clinical differences between COPD patients with and without MetS have not been extensively studied. We aimed to describe the clinical characteristics of patients with MetS and COPD. An observational, multicenter study of 375 patients hospitalized for a COPD exacerbation with spirometric confirmation was performed. We measured the components of the MetS and collected comorbidity information using the Charlson index and other conditions. Dyspnea, use of steroids, exacerbations, and hospitalizations were also investigated. The overall prevalence of MetS in COPD patients was 42.9 %, was more frequent in women (59.5 %) than men (40.8 %), p = 0.02, but with no differences in age and smoking history. COPD patients with MetS had greater % predicted FEV1, more dyspnea, and more comorbidity and used more inhaled steroids (all p < 0.05). Diabetes, osteoporosis, coronary artery disease, and heart failure were more frequent in patients with MetS. They had been hospitalized more frequently for any cause but not for COPD. In multivariate analysis, the presence of MetS was independently associated with greater FEV1, inhaled steroids use, osteoporosis, diabetes, and heart failure. MetS is a frequent condition in COPD patients, and it is associated with greater FEV1, more dyspnea, and more comorbidities.

Prácticas de Crianza Positiva: Entrenamiento a padres para reducir Bullying / Positive Child Rearing Practices: Parents training for reduce bullying

El estudio buscó evaluar la eficacia de un programa de prácticas de crianza positiva dirigido a padres para reducir el bullying y aumentar la conducta pro-social de sus hijos. Participaron ocho parejas y dos padres solteros de 10 niños identificados como bullies. La mitad de los padres conformó el grupo control y se entrenó a la otra mitad para identificar la conducta agresiva y pro-social de sus hijos, sus antecedentes y consecuentes. Durante ocho sesiones semanales se entrenó a los padres a establecer límites, reforzar la conducta pro-social y las alternas a las agresivas, a sobre-corregir, desaprobar levemente, castigar y extinguir la conducta agresiva. Padres y maestros registraron durante tres semanas de línea base y ocho de tratamiento, la frecuencia de emisión de conductas pro-sociales (hacer la tarea, ayudar con tareas domésticas y recoger sus juguetes) y de conducta agresiva física y verbal. Los resultados mostraron una reducción significativa de la conducta agresiva y un aumento de la pro-social respecto tanto a la línea base como a la frecuencia de emisión de esas conductas por los niños del grupo control. Notablemente, la conducta también cambió en la escuela. Se discute la efectividad de las intervenciones con padres para reducir la conducta de bullying en diferentes contextos.

The study aimed at assessing the effectiveness of a positive child rearing program with parents for reducing bullying and incrementing pro-social behavior of their children. Participants were eight couples and two single parents of 10 children identified as bullies. Half of the parents were assigned to a control group and the other half were trained to identify aggressive and pro-social behaviors of their children, as well as their antecedents and consequences. During eight weekly sessions parents were trained to set limits, reinforce both pro-social behavior and alternative responses to the aggressive ones, to correct, slightly disapprove, punish and extinguish aggressive behavior. Frequency of emission of specific pro-social behaviors (doing homework, helping in domestic chores and picking up toys) and of physical and verbal aggression was registered by parents and teachers during three weeks of base line and during eight weeks of treatment. Results showed a significant reduction of aggressive behavior and an increase of pro-social behavior compared both to base line and to the frequency of the same behaviors by children of the control group. Notably, behavior also changed at school. Results are discussed regarding the usefulness of interventions with parents in reducing bullying behavior by their children in different contexts.

Comorbidities and short-term prognosis in patients hospitalized for acute exacerbation of COPD: the EPOC en Servicios de medicina interna (ESMI) study.

BACKGROUND: Comorbidities are frequent in patients hospitalized for COPD exacerbation, but little is known about their relation with short-term mortality and hospital readmissions. Our hypothesis is that the frequency and type of comorbidities impair the prognosis within 12 weeks after discharge. METHODS: A longitudinal, observational, multicenter study of patients hospitalized for a COPD exacerbation with spirometric confirmation was performed. Comorbidity information was collected using the Charlson index and a questionnaire that included other common conditions not included in this index. Dyspnea, functional status, and previous hospitalization for COPD or other reasons among other variables were investigated. Information on mortality and readmissions for COPD or other causes was collected up to 3 months after discharge. RESULTS: We studied 606 patients, 594 men (89.9%), with a mean (SD) age of 72.6 (9.9) years and a postbronchodilator FEV1 of 43.2% (21.2). The mean Charlson index score was 3.1 (2.0). On admission, 63.4% of patients had arterial hypertension, 35.8% diabetes mellitus, 32.8% chronic heart failure, 20.8% ischemic heart disease, 19.3% anemia, and 34% dyslipemia. Twenty-seven patients (4.5%) died within 3 months. The Charlson index was an independent predictor of mortality (P < .003; OR,1.23; 95% CI, 1.07-1.40), even after adjustment for age, FEV1, and functional status measured with the Katz index. Comorbidity was also related with the need for hospitalization from the ED, length of stay, and hospital readmissions for COPD or other causes. CONCLUSIONS: Comorbidities are common in patients hospitalized for a COPD exacerbation, and they are related to short-term prognosis.

Intervenciones breves con adolescentes estudiantes rurales que consumen alcohol en exceso / Brief interventions with adolescent rural students who drink alcohol in excess

Debido a la falta de programas dirigidos a prevenir y tratar el consumo excesivo de alcohol en adolescentes de comunidades rurales, se evaluaron dos modalidades de corta intervención: a) programa breve de cinco sesiones y b) sesión de consejo breve. En una primera fase se realizó un estudio exploratorio, obteniendo un cuadro descriptivo del consumo de alcohol en adolescentes de tres comunidades rurales, mientras que en un segundo momento, mediante un diseño de grupos de comparación, se determinaron los efectos de ambas intervenciones sobre el patrón de consumo y otras variables psicosociales en 24 adolescentes rurales del estado de Aguascalientes (México). Se concluyó que ambas modalidades de intervención son efectivas para el trabajo con adolescentes rurales usuarios de alcohol.

Due to the lack of programs designed to prevent and treat problems related to alcohol consumption in adolescents in rural communities, two brief intervention modalities were evaluated: a) a brief program with five sessions and, b) a brief advice session. During the first stage, an exploratory study was undertaken, on the basis of which a descriptive chart of alcohol consumption among adolescents in three rural communities was obtained, while in the second stage, comparison groups were designed to determine the effects of both interventions on consumption patterns and other psychosocial variables in a sample of 24 rural adolescents of the state of Aguascalientes, Mexico. The conclusion was that both interventions are effective in working with rural adolescent alcohol users.

Resultados preliminares del Programa de Intervención Breve para Adolescentes que Inician el Consumo de Alcohol y otras Drogas / Preliminary study of a brief intervention program for adolescents who initiate alcohol and other drugs consumption

During the last two decades, alcohol, tobacco and illicit drug consumption among young people has come to be regarded as a serious public health problem, both in Mexico and internationally. This recognition has resulted from a trend toward higher levels of use, greater diversification of the types of drugs used and abused, and increased drug marketing. Epidemiological data show that most users initiate drug use when they are about 16 years old. However, the age of first drug experimentation appears to be decreasing, with recent reports indicating an average age 12 or 13 years at present. The societal costs of adolescent drug use cut across different domains including physical and mental health, car crashes, and morbidity and mortality related to substance misuse. The personal costs of teen drug use include school failure, drop-out, and truancy. Moreover, aggressive behavior and crime, risky sexual behaviour, and many other behavioural problems have been shown to be associated with adolescent drug use. Research from many different disciplines has increased knowledge about (a) important dimensions of adolescent substance use and (b) the processes and variables related to the origin and maintenance of addictive behavior among teenagers. Despite this growing body of knowledge, few current prevention and treatment programs are based on empirical investigation. Moreover, many current intervention programs have not been adequately evaluated in regard to effectiveness. A recent development in the addiction field is brief intervention (BI). BIs have been demonstrated to be effective in the treatment of addictive behavior among adult problem drinkers, with the most successful programs based on the Theory of the Social Learning. Only recently have BIs been tried with adolescent populations. While promising, little empirical research exists about the effectiveness of brief treatment with adolescents. The primary goals of BIs are to (a) reduce or eliminate substance consumption and (b) to mitigate the adverse effects of using alcohol or other drugs (i.e., harm reduction). While the goals of BIs are clear, the effectiveness of such programs with adolescents, despite their promise, is not well researched. For this reason, it is important to develop and empirically test BI programs for adolescents demonstrating problematic alcohol or other drug consumption. Schools represent a particularly good place to access adolescents who would benefit from BIs, and BIs represent an attractive alternative to the typical strategies used by school to address student substance use (i.e., suspension or expulsion). The main goal of this investigation was to develop and to evaluate a brief intervention program for teenagers with substance abuse (but who have not developed substance dependence) between 14 and 18 years old. The intervention program tries to: (a) promote a change in drug consumption through establishing consumption goals (in the case of the alcohol, moderation or abstinence; in the case of illegal drugs, abstinence); (b) identify high-risk situations in which use is probable; and (c) develop alternative strategies to these situations. The theorical bases of the intervention include Self-control Theory, Motivational Interviewing, Relapse Prevention and <>. Our brief intervention program consisted of six steps: 1. case detection, which involved the identification of adolescents who abuse alcohol or another drugs, by means of teacher's reports, legal and psychology personnel, trained by the investigators; 2. screening, which involved determining whether adolescents met inclusion criteria; 3. assessment, which addressed the frequency and amount of consumption and self-confidence to suitably face situation of probable drug; 4. induction to the program, the objective of which was to sensitize the adolescents about the importance of attending treatment; 5. intervention; and, 6. one, three and six months follow-up assessments. The intervention program consisted of four individual sessions with the participants in which they chose their own substance reduction goals, identified their high risk situations, developed coping plans for each high risk situation, and appraised the impact of their substance use on their own life-goals success. The researchers used a single-case design with 25 participants, 17 of whom had alcohol problems and eight of whom had marijuana problems. The age average of participants was 16 years (SD = 1.8), and 19 were male and six were female. The average age of first consumption was 14 years old (SD = 1.72); the average duration of substance use was 18 months. From the complete sample, 45% reported consumption one or twice per week, 22% reported daily consumption, and the remainder consumed once a month. Results indicated that from the 25 participants, 24 demonstrated changes from the baseline in their consumption pattern (measured by frequency and quantity) during intervention and at follow-up assessments. Self-efficacy levels (self-perceptions about the capability to abstain or use moderately in high risk situations) changed as well. Specifically, among the adolescents who consumed alcohol a one-way ANOVA revealed significant changes in average consumption between the baseline, treatment, and follow-up phases F(2.48) = 17.691, p < .001. Bonferroni's post-hoc tests showed differences between baseline ( = 8.89, SD = 3.55) and treatment ( = 4.46, SD = 3.27), and between baseline and the follow-up ( = 3.29, SD = 1.35). Student's t tests for each subject showed that 16 adolescents significantly reduced their alcohol consumption from the baseline to the follow-up. Only one participant demonstrated increased use (from five standard drinks per drinking occasion at the baseline to 5.90 standard drinks at the follow-up). Regarding consumers of marijuana, a one-way ANOVA showed significant changes in consumption across the baseline, treatment and follow-up phases F(2.21) = 8.219, p = .002. Bonferroni's post-hoc tests showed significant differences between the baseline ( = 18.23, SD = 16.62) treatment phases ( = 1.07, SD = 0.77), and between the baseline and the follow-up phases ( = 1.59, SD = 1.06). An additional one-way ANOVA revealed significant changes in self-efficacy. Specifically, participants demonstrated increased self-efficacy in situations including: Unpleasant emotions, Pleasant emotions, Testing personal control, Conflict with others, Social pressure, and Pleasant time with others (all p < .01), F(2.78) = 24.30, 12.47, 11.34, 11.02, 16.91 and 25.62, respectively. Self-efficacy in regard to Physical discomfort and Urges and temptations to drink also showed significant changes, but at p < .05 F(2.78) = 3.97 and 3.26, respectively. Finally, in order to evaluate the impact of the intervention on problems that participants associated with their alcohol use (or other drugs), seven areas were examined: School, Health, Cognitive, Interpersonal, Family, Legal and Economic. At the end of the treatment, there was a reduction in the number of problems related to these seven areas, compared with the baseline.

En las últimas décadas, el abuso de drogas legales e ilegales en los jóvenes ha sido considerado como un serio problema de salud pública, tanto en el ámbito internacional como en nuestro país. Los estudios epidemiológicos indican que la mayoría de los consumidores experimentan por primera vez con drogas alrededor de los 16 años, pero esta experimentación continúa disminuyendo presentándose en promedio a los 12 o 13 años. Esto representa altos costos para la sociedad y el individuo. Por ejemplo, en áreas de la salud se incrementan los costos de la atención médica, los servicios de salud mental y los tratamientos especializados, además de aumentar la probabilidad de accidentes y muertes relacionadas con el abuso; en el área escolar se presenta el fracaso y/o la deserción escolar, y la expulsión de los estudiantes por parte de las instituciones; y en el área social se pueden presentar conductas agresivas y/o delictivas, contacto sexual de riesgo y otros problemas de conducta relacionados con el consumo de sustancias. De los diferentes programas existentes, resaltan las intervenciones breves en el tratamiento de usuarios que abusan pero que no dependen de las sustancias. Este tipo de intervenciones se basan en la Teoría del Aprendizaje Social y están diseñadas para reducir los patrones de abuso de alcohol u otras drogas. Sin embargo, la aplicación de las intervenciones breves se ha realizado principalmente en adultos, y es hasta últimas fechas que éstas se han adaptado a población adolescente que abusa de las sustancias, sin tenerse todavía resultados concluyentes. Es por esto que es fundamental desarrollar programas de intervención breve como una alternativa para adolescentes que inician el abuso de alcohol u otras drogas. Otro punto que requiere atención es el desarrollo de estrategias para detectar los casos en las escuelas, con la finalidad de ofrecer los servicios de atención en las propias instituciones educativas sin que el adolescente tenga consecuencias como la suspensión o la expulsión. Ante este fenómeno se ha recomendado fortalecer acciones que se basan en la identificación temprana de patrones de consumo que ponen en riesgo al adolescente a diferentes problemas relacionados con el abuso de las drogas. Estos programas se deben caracterizar por ser costo-eficientes, breves y capaces de instrumentarse en una variedad de escenarios, así como de aplicarse a una variedad de culturas. Por lo tanto, el objetivo de esta investigación fue desarrollar y evaluar un programa de intervención breve para adolescentes de entre 14 y 18 años de edad, estudiantes de nivel medio y medio superior, que consumen alcohol en exceso u otras drogas, y que presentan problemas relacionados con este patrón de consumo pero sin cubrir los síntomas físicos de la dependencia. Para realizar la evaluación se utilizó un diseño de caso único con 25 réplicas, 17 casos de consumo de alcohol y 8 casos de consumo de mariguana. De los 25 adolescentes que participaron en el estudio, 24 mostraron una disminución en el patrón de consumo (cantidad y frecuencia de consumo), al comparar las mediciones de los datos recabados en las fases de línea base, tratamiento y seguimiento. Así mismo, se dieron cambios en el nivel de auto-eficacia (percepción de la capacidad de los sujetos para controlar sus situaciones de consumo), es decir, al finalizar el tratamiento los adolescentes se percibieron a sí mismos con mayor capacidad para controlar la cantidad de consumo en situaciones de riesgo. Además, al final del tratamiento los sujetos reportaron una reducción del número de problemas relacionados con su consumo. Esta investigación es uno de los primeros esfuerzos por demostrar el impacto de las intervenciones breves en el patrón de consumo de los adolescentes. Las limitaciones del estudio fueron que no se determinó el efecto específico de cada uno de los componentes del programa ni tampoco se evaluó la presencia de otras conductas problemáticas (comorbilidad). Sin embargo, esta investigación ofrece un apoyo empírico a los programas de intervención breve en población adolescente de nuestro país.