[Lung-cancer screening program in Mexico]. / Detección temprana de cáncer de pulmón en México.

La detección temprana de cáncer pulmonar (CP) en población de alto riesgo tiene el potencial de diagnosticar la enfermedad en estadios tempranos y facilitar el tratamiento oportuno con el fin de disminuir la tasa de mortalidad. En México, como en otros países en vías de desarrollo, además del tabaquismo, la exposición al humo de leña se posiciona como uno de los principales factores de riesgo para desarrollar CP, lo cual no se ha considerado en estudios de tamizaje previamente publicados. Distintas interrogantes surgen en relación con quiénes son las personas que presentan un alto riesgo de desarrollar CP en América Latina, cuál es el costo-beneficio de poner en marcha un programa de detección oportuna de CP en México y cuáles son los obstáculos que los países de la región enfrentan para su implementación.

Lung cancer screening has the potential to be diagnosed at an early stage which increases the possibility of curative treatment in order to decrease the mortality rate. In Mexico, as in other developing nations, along with wood smoke exposure is one of the main risk factors for developing lung cancer, not considered in previously published screening trials. Different questions arise concerning the population at higher risk to develop lung cancer in Latin America, the cost-benefit of implementing a lung cancer screening program and the obstacles facing developing countries when implementing a detection program. To knowledge, there are no lung cancer screening trials in Mexico.

Pediatric asthma treatment: What to do when international guideline recommendations do not agree.

BACKGROUND: There was a need for a solid asthma guideline in Mexico to update and unify asthma management. Because high-quality asthma guidelines exist worldwide, in which the latest evidence on asthma management is summarized, the ADAPTE approach allows for the development of a national asthma guideline based on evidence from already existing guidelines, adapted to national needs. OBJECTIVE: To fuse evidence from the best asthma guidelines and adapt it to local needs with the ADAPTE approach. METHODS: The Appraisal of Guidelines for Research and Evaluation (AGREE) II asthma guidelines were evaluated by a core group to select 3 primary guidelines. For each step of asthma management, clinical questions were formulated and replied according to (1) evidence in the primary guidelines, (2) safety, (3) Cost, and (4) patient preference. The Guidelines Development Group, composed of a broad range of experts from medical specialties, primary care physicians, and methodologists, adjusted the draft questions and replies in several rounds of a Delphi process and 3 face-to-face meetings, taking into account the reality of the situation in Mexico. We present the results of the pediatric asthma treatment part. RESULTS: Selected primary guidelines are from the British Thoracic Society and Scottish Intercollegiate Guidelines Network (BTS/SIGN), Global Initiative for Asthma (GINA), and Spanish Guidelines on the Management of Asthma (GEMA) 2015, with 2016 updates. Recommendations or suggestions were made for asthma treatment in Mexico. In this article, the detailed analysis of the evidence present in the BTS/SIGN, GINA, and GEMA sections on the (non) pharmacologic treatment of pediatric asthma, education, and devices are presented for 2 age groups: children 5 years or younger and children 6 to 11 years old with asthma. CONCLUSION: For the pediatric treatment and patient education sections, applying the AGREE II and Delphi methods is useful to develop a scientifically sustained document, adjusted to the Mexican situation, as is the Mexican Guideline on Asthma.

Diagnostic Value of the Morphometric Model and Adjusted Neck Circumference in Adults with Obstructive Sleep Apnea Syndrome.

BACKGROUND: Obstructive sleep apnea syndrome is a major public health problem. The morphometric model and the Sleep Apnea Clinical Score are widely used to evaluate adults; however, neither of these tools has been validated in a Mexican population. OBJECTIVE: To determine the diagnostic value of the morphometric model and the Sleep Apnea Clinical Score and compare them with conventional clinical instruments. METHODS: A total of 97 individuals were recruited prospectively. Initial screening excluded 36, of whom nine were subjects without apnea; the remaining 52 were consecutive patients with obstructive sleep apnea syndrome diagnosed by nocturnal polysomnography. Diagnostic values of each test were calculated. RESULTS: Obstructive sleep apnea syndrome patients had significantly higher scores with both instruments than controls: morphometric model: 61.3 (95% CI: 45.5-75.3) vs. 41.0 (95% CI: 35.6-45.6); Sleep Apnea Clinical Score: 45.3 (95% CI: 39.5-40.3) vs. 36 (95% CI: 34.0-36.5), respectively. For severe cases, the best cutoff point for morphometric model was 46, with a sensitivity of 81% (95% CI: 62.5-92.6) and specificity of 46.7% (95% CI: 66.4-100), while for Sleep Apnea Clinical Score it was > 48, with a sensitivity of 61% (95% CI: 46.1-74.2) and specificity of 80.4% (95% CI: 66-90.6). CONCLUSIONS: A morphometric model value of ≥ 46 or an adjusted neck circumference (Sleep Apnea Clinical Score) > 48 were adequate for diagnosing obstructive sleep apnea syndrome.

Altitude and Breathing during Sleep in Healthy Persons and Sleep Disordered Patients: A Systematic Review.

Objetive The aim of this systematic review is to analyze the recent scientific evidence of the clinical effects of altitude on breathing during sleep in healthy persons and sleep disordered patients. Material and Methods A search was carried out in PubMed and Scopus looking for articles published between January 1, 2010 and December 31, 2021, in English and Spanish, with the following search terms: "sleep disorders breathing and altitude". Investigations in adults and carried out at an altitude of 2000 meters above mean sea level (MAMSL) or higher were included. The correlation between altitude, apnea hypopnea index (AHI) and mean SpO2 during sleep was calculated. Results 18 articles of the 112 identified were included. A good correlation was found between altitude and AHI (Rs = 0.66 P = 0.001), at the expense of an increase in the central apnea index. Altitude is inversely proportional to oxygenation during sleep (Rs = -0.93 P = 0.001), and an increase in the desaturation index was observed (3% and 4%). On the treatment of respiratory disorders of sleeping at altitude, oxygen is better than servoventilation to correct oxygenation during sleep in healthy subjects and acetazolamide controlled respiratory events and oxygenation during sleep in patients with obstructive sleep apnea under treatment with CPAP. Conclusions Altitude increases AHI and decreases oxygenation during sleep; oxygen and acetazolamide could be an effective treatment for sleep-disordered breathing at altitude above 2000 MAMSL.

[Burnout syndrome among medical residents during the influenza A H1N1 sanitary contigency in Mexico]. / Síndrome de burnout en médicos mexicanos en entrenamiento durante una contingencia sanitaria por virus de influenza A H1N1.

OBJECTIVE: To measure the degree of stress among medical residents at a Third Level Hospital in Mexico City during the sanitary contingency caused by the AH1N1 influenza virus. METHODS: A transversal descriptive study with a non-probabilistic sample of 99 medical residents with different fields of specialization related to respiratory medicine. Researchers applied the Maslach Burnout Inventory questionnaire to evaluate three dimensions: emotional fatigue, depersonalization, and personal fulfillment. The survey was self-administered and anonymous, and the study was conducted during the first AH1N1 influenza virus outbreak (April 23 to May 10, 2009). During that period, the hospital underwent a process of reorganization that included cancelling vacation periods for all medical residents and adjusting duty rosters. RESULTS: The highest proportion of medical residents with burnout syndrome was those in their second year of specialization in the area of pneumology. Results also showed that medical residents under 30 years of age had a higher probability of presenting burnout syndrome. No significant differences were found regarding the residents' place of origin.

Spirometry quality-control strategies in a multinational study of the prevalence of chronic obstructive pulmonary disease.

UNLABELLED: We report the characteristics of a centralized spirometry quality-control program developed for a population-based survey of the prevalence of chronic obstructive pulmonary disease in 5 cities: São Paulo, Brazil; México City, México; Montevideo, Uruguay; Santiago, Chile; and Caracas, Venezuela (the Latin American Project for the Investigation of Obstructive Lung Diseases [PLATINO]). METHODS: We developed and used a 3-level quality-control system. Level 1: The spirometer used in the survey (EasyOne), gives quality-control messages to the user/clinician. All the spirometry technicians were trained by the same team, with the aim of meeting what became the 2005 spirometry quality criteria of the American Thoracic Society/European Respiratory Society (ATS/ERS). Level 2: In each of the 5 cities a local supervisor identified poor-quality spirometries that needed to be repeated. Level 3: Once a week during the survey, all spirometry results were sent via e-mail to the study's quality-control center in México City for review and feedback. RESULTS: In the overall totals at the end of the study, 94% of the 5,315 subjects had spirometries that met the 1994 ATS quality criteria, and 89% met the 2005 ATS/ERS criteria. In their overall totals at the end of the study, 90% of the 64 spirometry technicians were successful in getting 86% of their subjects to meet the 1994 ATS criteria, and got 75% of their subjects to meet the 2005 ATS/ERS criteria. In the first 10 subjects they tested, 90% of the 64 spirometry technicians were successful in getting 70% of their subjects to meet the 1994 ATS criteria, and got 60% of their subjects to meet the 2005 ATS/ERS criteria. CONCLUSIONS: Standardization of equipment, training, and supervision of spirometry is essential in a multinational spirometry survey. Centralized quality control can be done via e-mail with good reliability and low cost.

[Agreement between oxygen desaturation index and apnea-hypopnea index in adults with suspected obstructive sleep apnea at an altitude of 2240 m]. / Indice de desaturación de oxígeno frente a índice de apneas-hipopneas en adultos con sospecha de apnea obstructiva durante el sueño a 2.240 m de altitud.

OBJECTIVE: Altitude can affect the diagnostic accuracy of portable monitors used to diagnose suspected obstructive sleep apnea syndrome on the basis of oxygen desaturation measurements. The aim of this study was to determine agreement between the desaturation index measured by oximetry and the apnea-hypopnea index measured by polysomnography in Mexico City (2240 m above sea level). We also wished to determine agreement between the desaturation index and the respiratory disturbance index measured by monitoring airflow with a single-channel recording device. PATIENTS AND METHODS: We used standard polysomnography and nocturnal oximetry to simultaneously measure the apnea-hypopnea index and the desaturation index, respectively, in a group of 38 patients aged over 18 years with suspected obstructive sleep apnea syndrome. In a second group of 30 patients, we compared the desaturation index to the respiratory disturbance index, which we measured using a single-channel device monitoring nasal airflow. RESULTS: The mean (SD) intraclass correlation coefficient between the apnea-hypopnea index and the desaturation index was 0.89 (0.03) (95% confidence interval, 0.83-0.96), and the mean of the differences was -0.9 (14.2). The mean intraclass correlation coefficient for the desaturation index and the respiratory disturbance index was 0.93 (0.02) (95% confidence interval, 0.89-0.97), and the mean of the differences was -6.6 (8.3). CONCLUSIONS: Agreement was high between the desaturation index and both the apnea-hypopnea index and the respiratory disturbance index in adults with suspected obstructive sleep apnea syndrome in Mexico City.

[Continuous positive airway pressure used by adults with obstructive sleep apneas after prescription in a public referral hospital in Mexico City]. / Uso de CPAP en adultos con síndrome de apneas obstructivas durante el sueño después de prescripción en un hospital público de referencia de la Ciudad de México.

OBJECTIVE: The aim of this study was to analyze the frequency of initiation of continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea syndrome (OSAS) in a referral hospital in Mexico City serving mainly patients without public health insurance coverage and to assess their level of adherence. PATIENTS AND METHODS: Patients with OSAS diagnosed by polysomnography or by simplified respiratory polygraphy for whom nasal CPAP was prescribed were enrolled in the study. Titration of CPAP was performed during polysomnography or with an automatic CPAP device. Compliance with treatment was assessed during a medical visit or by telephone interview. RESULTS: A total of 304 patients were enrolled upon prescription of nasal CPAP; 169 (55.5%) either purchased a device or were provided with one by the social security system. The patients most seriously ill and who had public health insurance coverage were the ones who most often acquired a device. These patients took 1.5 months to obtain the equipment and had a compliance rate of 80% at a mean 34 months of follow-up. The respiratory events index was correlated with compliance, whereas excessive daytime sleepiness (Epworth scale score) and body mass index were predictors of therapeutic CPAP pressure. CONCLUSIONS: Nearly half the patients who were prescribed CPAP did not acquire the device. Most of those who acquired a device adhered to the treatment. In Mexico access to procedures for diagnosing OSAS is limited and access to treatment is also restricted for patients who do not have public health insurance coverage.

[Spirometry reference values after inhalation of 200 microg of salbutamol]. / Valores de referencia para la espirometría después de la inhalación de 200 microg de salbutamol.

OBJECTIVE: The criteria for disease severity established by the Global Initiative for Chronic Obstructive Lung Disease are based on forced expiratory volume in 1 second (FEV1) expressed as a percentage of the predicted value after application of a bronchodilator. This study aims to determine postbronchodilator spirometry reference values. SUBJECTS AND METHODS: A cluster sample of subjects aged 40 years or over was chosen to be representative of the metropolitan areas of 5 Latin American cities (São Paulo, Mexico City, Montevideo, Santiago, and Caracas). Spirometry was performed on 5183 subjects following the recommendations of the American Thoracic Society before and after inhalation of 200 microg of salbutamol. Multiple linear regression equations were fitted for the postbronchodilator spirometric values-FEV1, forced expiratory volume in 6 seconds (FEV6), peak expiratory flow rate, forced vital capacity (FVC), FEV1/FEV6, FEV1/FVC and forced expiratory flow between 25% and 75% of vital capacity (FEF25-75). These were adjusted for sex, age, and height in 887 asymptomatic subjects with no history of lung disease. RESULTS: The postbronchodilator reference values for FEV1, FEV1/FVC, and FEV1/FEV6 were on average 3% higher than those obtained before bronchodilation. This apparently small difference caused an upward shift in the 5th percentile (lower limit of normal) of the predicted values. When prebronchodilation instead of postbronchodilation reference values were used, 3.2% of the results for airflow obstruction in our population of over-40-year-olds were false negatives. CONCLUSIONS: The reported reference values are more appropriate for postbronchodilator spirometry and make it possible to reduce the number of misclassifications.

Long-Term Stability of a Portable Carbon Monoxide Single-Breath Diffusing Capacity Instrument.

BACKGROUND: The 2005 American Thoracic Society/European Respiratory Society guidelines for single-breath diffusing capacity of the lung for carbon monoxide (DLCO) recommend a weekly biological control test and/or DLCO simulator to detect instrument error drift. Very little has been published regarding the results of such a quality assurance program. Our aim was to analyze the long-term stability of a portable DLCO instrument. METHODS: We used a new EasyOne Pro system and checked its accuracy using a DLCO simulator with 2 reference gases (concentration A: carbon monoxide [CO] = 0.1% and helium = 6.52%; concentration B: CO = 0.08% and helium = 7.21%) during the first 3 y of use in our large clinical laboratory. To detect instrument drift, a healthy woman (MSC), age 43 y old at baseline, tested herself every week during this period of time. RESULTS: More than 6,000 spirometry and 5,000 DLCO maneuvers were done using this instrument for patients during these 3 y. There were no failures in the daily volume and flow checks or the CO and helium calibration checks performed automatically by the instrument. The differences between the simulator DLCO and the measured DLCO were -0.91 ± 1.33 mL/min/mm Hg and -0.61 ± 1.45 mL/min/mm Hg for concentration A and concentration B, respectively. The results of the 110 biological control tests were: mean 30.8 ± 1.7 mL/min/mm Hg (95% CI 30.5-31.1), coefficient of variation of 5.4% in DLCO, and repeatability of 2.5 mL/min/mm Hg. Only 4 measurements were outside ±3 mL/min/mm Hg (3.6%). Her mean alveolar volume was 4.2 ± 0.25 L with coefficient of variation of 6.2%; her inspired volume was 3.05 ± 0.14 L, and coefficient of variation = 4.5%. CONCLUSIONS: Measurements of DLCO were stable over the 3-y period without any need for manual recalibration of the instrument. The biological control was as good as the DLCO simulator to evaluate this kind of device in a long-term laboratory quality control program.

[Mexican Asthma Guidelines: GUIMA 2017]. / Guía Mexicana del Asma: GUIMA 2017.

BACKGROUND: The need for a national guideline, with a broad basis among specialists and primary care physicians was felt in Mexico, to try unifying asthma management. As several high-quality asthma guidelines exist worldwide, it was decided to select the best three for transculturation. METHODS: Following the internationally recommended methodology for guideline transculturation, ADAPTE, a literature search for asthma guidelines, published 1-1-2007 through 31-12-2015 was conducted. AGREE-II evaluations yielded 3/40 most suitable for transculturation. Their compound evidence was fused with local reality, patient preference, cost and safety considerations to draft the guideline document. Subsequently, this was adjusted by physicians from 12 national medical societies in several rounds of a Delphi process and 3 face-to-face meetings to reach the final version. RESULTS: Evidence was fused from British Thoracic Society Asthma Guideline 2014, Global Initiative on Asthma 2015, and Guía Española del Manejo del Asma 2015 (2016 updates included). After 3 Delphi-rounds we developed an evidence-based document taking into account patient characteristics, including age, treatment costs and safety and best locally available medication. CONCLUSIONS: In cooperation pulmonologists, allergists, ENT physicians, paediatricians and GPs were able to develop an evidence-based document for the prevention, diagnosis and treatment of asthma and its exacerbations in Mexico.

Antecedentes: Con el objetivo de unificar el manejo del asma en México se estructuró una guía clínica que conjunta el conocimiento de diversas especialidades y la atención en el primer nivel de contacto. Se seleccionaron 3 guías publicadas en el ámbito internacional para su transculturación. Métodos: Conforme a la metodología ADAPTE se usó AGREE II después de la búsqueda bibliográfica de guías sobre asma publicadas entre 2007 y 2015. Se fusionó la realidad local con la evidencia de 3/40 mejores guías. El documento inicial fue sometido a la revisión de representantes de 12 sociedades médicas en varias rondas Delphi hasta llegar a la versión final. Resultados: Las guías base fueron la British Thoracic Society Asthma Guideline 2014, la Global Initiative on Asthma 2015 y la Guía Española del Manejo del Asma 2015. Después de 3 rondas Delphi se desarrolló un documento en el que se consideraron las características de los pacientes según edad, costos de los tratamientos y perfiles de seguridad de los fármacos disponibles en México. Conclusión: Con la cooperación de neumólogos, alergólogos, otorrinolaringólogos, pediatras y médicos generales se llegó a un consenso basado en evidencia, en el que se incluyeron recomendaciones sobre prevención, diagnóstico y tratamiento del asma y sus crisis.

The long-term stability of portable spirometers used in a multinational study of the prevalence of chronic obstructive pulmonary disease.

BACKGROUND: We report the performance of an ultrasound-based portable spirometer (EasyOne) used in a population-based survey of the prevalence of chronic obstructive pulmonary disease, conducted in 5 Latin American cities: São Paulo, Brazil; México City, México; Montevideo, Uruguay; Santiago, Chile; and Caracas, Venezuela (the Latin American COPD Prevalence Study [PLATINO]). METHODS: During the survey period (which ranged from 3 months to 6 months in the various locations) we collected daily calibration data from the 70 EasyOne spirometers used in the 5 survey cities. The calibrations were conducted with a 3-L syringe, and the calibration data were stored in the spirometer's database. RESULTS: Ninety-seven percent of the calibration volumes were within +/- 64 mL (2.1%) of the 3-L calibration signal. Excluding data from the first city studied (São Paulo), where one calibration syringe had to be replaced, 98% of the calibration checks were within +/- 50 mL (1.7%). The measured volume was affected only minimally by the syringe's peak flow or emptying time. CONCLUSION: In these 70 EasyOne spirometers neither calibration nor linearity changed during the study. Such calibration stability is a valuable feature in spirometry surveys and in the clinical setting.

[Precision and accuracy of "a pocket" pulse oximeter in Mexico City]. / Precisión y exactitud de un oxímetro de pulso "de bolsillo" en la ciudad de México.

BACKGROUND: Pulse oximeters are frequently used in the clinical practice and we must known their precision and accuracy. The objective was to evaluate the precision and accuracy of a "pocket" pulse oximeter at an altitude of 2,240 m above sea level. METHODS: We tested miniature pulse oximeters (Onyx 9,500, Nonin Finger Pulse Oximeter) in 96 patients sent to the pulmonary laboratory for an arterial blood sample. Patients were tested with 5 pulse oximeters placed in each of the fingers of the hand oposite to that used for the arterial puncture. The gold standard was the oxygen saturation of the arterial blood sample. RESULTS: Blood samples had SaO2 of 87.2 +/- 11.0 (between 42.2 and 97.9%). Pulse oximeters had a mean error of 0.28 +/- 3.1%. SaO2 = (1.204 x SpO2) - 17.45966 (r = 0.92, p < 0.0001). Intraclass correlation coefficient between each of five pulse oximeters against the arterial blood standard ranged between 0.87 and 0.99. HbCO (2.4 +/- 0.6) did not affect the accuracy. CONCLUSIONS: The miniature oximeter Nonin is precise and accurate at 2,240 m of altitude. The observed levels of HbCO did not affect the performance of the equipment. The oximeter good performance, small size and low cost enhances its clinical usefulness.

Reference Values for the Diffusing Capacity Determined by the Single-Breath Technique at Different Altitudes: The Latin American Single-Breath Diffusing Capacity Reference Project.

BACKGROUND: The lung diffusion capacity (DLCO) determined by the single-breath technique greatly helps in the differential diagnosis and classification of severity of common lung diseases. However, widespread use of single-breath DLCO tests in Latin America has been limited, in part, by the lack of appropriate reference values. Our objective was to derive robust reference equations for single-breath DLCO from healthy Hispanic adults, using the most recent guidelines and taking into account altitude above sea level and hemoglobin. METHODS: We recruited healthy adults from Caracas (690 m), Santiago (650 m), Mexico City (2,240 m), and Bogota (2,640 m). DLCO testing was completed using an instrument that exceeds American Thoracic Society/European Respiratory Society 2005 guidelines for spirometry and single-breath DLCO and provided centralized training and a quality assurance program. RESULTS: We included 480 healthy Hispanic adults (58.3% women) with a mean age of 46 y (range 22-83 y). Their mean ± SD single-breath DLCO was 30.4 ± 9.2 mL/min/mm Hg. Results as a percentage of predicted by Crapo's reference values (the closest to obtained values) were 83 ± 10% (Caracas), 91 ± 10% (Santiago), 104 ± 17% (Mexico City), and 118 ± 19% (Bogota), and current suggested adjustments by hemoglobin or altitude did not correct differences, especially in Santiago and Caracas. CONCLUSIONS: We recommend these new single-breath DLCO reference equations to predict single-breath DLCO in Latin America performed with current instruments and procedures and including as a predictor altitude above sea level.

[Obesity and asthma]. / Obesidad y asma.

Obesity and asthma are two disorders of high and increasing worldwide prevalence. A consistent association between obesity and asthma has been recently found in case-control, cross-sectional and longitudinal studies. This association is more consistent in women after the puberty. Moreover, an improvement in the severity of asthma has been described after weight reduction in obese patients. A causal association between asthma and obesity may represent an additional respiratory work that could increase the morbidity and medical expenditures. The most striking studies which demonstrate association between obesity and asthma and the possible causal mechanisms are reviewed.

[Breathing during sleep in patients with chronic obstructive pulmonary disease at an altitude of 2,240 meters]. / Respiración durante el sueño en pacientes con enfermedad pulmonar obstructiva crónica a una altitud de 2,240 metros.

INTRODUCTION: Patients with chronic obstructive pulmonary disease (COPD) dwellers of Mexico City may present a significant hypoxemia as a consequence of the lung disease and the altitude (2,240 m). These patients usually show a poorer hypoxemia during sleep. OBJECTIVE: To describe breathing during sleep in COPD patients residing at the altitude of Mexico City and the effect of supplementary oxygen. METHODS: A total of thirteen patients with COPD underwent standard polysomnography during two consecutive nights breathing room air or oxygen. Nine normal non-obese subjects matched by age and gender were also studied during one night breathing room air. RESULTS: Mean SaO2 during sleep was significantly lower in patients than in controls (85 +/- 5 vs. 93 +/- 2, p < 0.001). Oxygen desaturation was reversed with supplementary oxygen in all patients. However, sleep parameters were not different in patients and controls and did not change with oxygen. COPD patients were thachypneic in all sleep stages (18-20 vs. 13-14; p < 0.001) and this tachypnea persisted with oxygen. CONCLUSION: A substantial nighttime desaturation was corrected with oxygen in all COPD patients studied at this altitude. Nonetheless, sleep quality was similar in patients and controls and did not change when patients breathed oxygen.

Detección temprana de cáncer de pulmón en México / Lung-cancer screening program in Mexico

Resumen: La detección temprana de cáncer pulmonar (CP) en población de alto riesgo tiene el potencial de diagnosticar la enfermedad en estadios tempranos y facilitar el tratamiento oportuno con el fin de disminuir la tasa de mortalidad. En México, como en otros países en vías de desarrollo, además del tabaquismo, la exposición al humo de leña se posiciona como uno de los principales factores de riesgo para desarrollar CP, lo cual no se ha considerado en estudios de tamizaje previamente publicados. Distintas interrogantes surgen en relación con quiénes son las personas que presentan un alto riesgo de desarrollar CP en América Latina, cuál es el costo-beneficio de poner en marcha un programa de detección oportuna de CP en México y cuáles son los obstáculos que los países de la región enfrentan para su implementación.

Abstract: Lung cancer screening has the potential to be diagnosed at an early stage which increases the possibility of curative treatment in order to decrease the mortality rate. In Mexico, as in other developing nations, along with wood smoke exposure is one of the main risk factors for developing lung cancer, not considered in previously published screening trials. Different questions arise concerning the population at higher risk to develop lung cancer in Latin America, the cost-benefit of implementing a lung cancer screening program and the obstacles facing developing countries when implementing a detection program. To knowledge, there are no lung cancer screening trials in Mexico.

Respiratory health in Latin America: number of specialists and human resources training.

Latin America is made up of a number of developing countries. Demographic changes are occurring in the close to 600 million inhabitants, in whom a significant growth in population is combined with the progressive ageing of the population. This part of the world poses great challenges for general and respiratory health. Most of the countries have significant, or even greater, rates of chronic respiratory diseases or exposure to risk. Human resources in healthcare are not readily available, particularly in the area of respiratory disease specialists. Academic training centers are few and even non-existent in the majority of the countries. The detailed analysis of these conditions provides a basis for reflection on the main challenges and proposals for the management and training of better human resources in this specialist area.