Quality of Pulmonary Function Tests in Participants with Down Syndrome / Calidad de los test de función pulmonar en participantes con síndrome de Down

Introduction: People with Down syndrome (DS) have high respiratory morbidity, evaluating their respiratory health with standardized, objective tests is desirable. Thus, the objective of this study was to evaluate the technical quality of Pulmonary Function Tests (PFTs) to determine which ones are most suitable for this population. Methods: Participants included children, teenagers and adults with DS, 5 years of age or older (n = 302). The technical quality of the impulse oscillometry system (IOS), forced spirometry, lung-diffusing capacity for carbon monoxide (DLCO), and 6-min walk test (6MWT) were analyzed by age group. Capnography and pulse oximetry were included in the study. Technical quality was determined on the basis of current international PFTs standards. Results: Fifty-one percent of participants were males. A total of 184 participants (71%) who completed the IOS fulfilled the quality criteria, while 210 (70%) completed the 6MWT. Performance on forced spirometry and DLCO was poor. All pulse oximetries and 96% percent heart rates obtained had good quality, but exhaled carbon dioxide (PetCO2) and respiratory rate (RR) showed deficient repeatability. Conclusions: IOS appears to be the most reliable instrument for evaluating lung mechanics in individuals with DS

Introducción: Las personas con síndrome de Down (SD) tienen una elevada morbilidad respiratoria, por lo que se recomienda evaluar su salud respiratoria con test objetivos estandarizados. El objetivo de este estudio fue evaluar la calidad técnica de los test de función pulmonar (TFP) para determinar cuáles son los más adecuados para este tipo de población. Métodos: Entre los participantes se incluyeron niños, adolescentes y adultos con SD y edad ≥ 5 años (n = 302). Se analizaron por grupos de edad la calidad técnica de la oscilometría de impulso (IOS), la oscilometría forzada, la capacidad pulmonar de difusión del monóxido de carbono (DLCO) y de la prueba de la marcha de 6 minutos (6MWT). Se incluyeron en el análisis la capnografía y la oximetría de pulso. La calidad técnica se determinó de acuerdo con los estándares internaciones actuales para los TFP. Resultados: El 51% de los pacientes eran varones. Un total de 184 participantes (71%) cumplieron los criterios de calidad de la IOS, mientras que 201 (70%) completaron la prueba 6MWT. El desempeño de la espirometría forzada y de la DLCO fue reducido. Todas las oximetrías de pulso que se obtuvieron, así como el 96% de las frecuencias de pulso presentaron buena calidad. Sin embargo, tanto el dióxido de carbono exhalado (PetCO2) como la frecuencia respiratoria (FR) presentaron una reproducibilidad deficiente. Conclusiones: La IOS parece ser la herramienta más fiable para la evaluación de la mecánica pulmonar en individuos con SD

Quality of Pulmonary Function Tests in Participants with Down Syndrome.

INTRODUCTION: People with Down syndrome (DS) have high respiratory morbidity, evaluating their respiratory health with standardized, objective tests is desirable. Thus, the objective of this study was to evaluate the technical quality of Pulmonary Function Tests (PFTs) to determine which ones are most suitable for this population. METHODS: Participants included children, teenagers and adults with DS, 5 years of age or older (n=302). The technical quality of the impulse oscillometry system (IOS), forced spirometry, lung-diffusing capacity for carbon monoxide (DLCO), and 6-min walk test (6MWT) were analyzed by age group. Capnography and pulse oximetry were included in the study. Technical quality was determined on the basis of current international PFTs standards. RESULTS: Fifty-one percent of participants were males. A total of 184 participants (71%) who completed the IOS fulfilled the quality criteria, while 210 (70%) completed the 6MWT. Performance on forced spirometry and DLCO was poor. All pulse oximetries and 96% percent heart rates obtained had good quality, but exhaled carbon dioxide (PetCO2) and respiratory rate (RR) showed deficient repeatability. CONCLUSIONS: IOS appears to be the most reliable instrument for evaluating lung mechanics in individuals with DS.

Diffusing Capacity of the Lung for Carbon Monoxide in Mexican/Latino Children. Quality Control and Reference Values.

RATIONALE: Single-breath diffusing capacity of the lung for carbon monoxide (DlCOsb) values are used to evaluate gas exchange; however, the quality of maneuvers performed by children has not been evaluated, and reference values for young people living at moderate altitudes are not well established. OBJECTIVES: Our objectives were 1) to determine whether DlCOsb maneuvers performed by a pediatric population would meet 2017 European Respiratory Society/American Thoracic Society (ERS/ATS) quality control standards; and 2) to report normal DlCOsb values for Mexican/Latino children and adolescents living at moderate altitudes. METHODS: This study involved healthy young people 4-20 years of age from the metropolitan area of Mexico City (2,240 m above sea level) who were recruited in schools from July 2014 to August 2017. DlCOsb testing was performed according to the 2005 ATS/ERS standards, and the quality control of each maneuver was analyzed according to the 2017 ERS/ATS standards. We constructed models for DlCOsb with linear and quadratic terms for weight, height, and age as independent variables using shrinkage statistics, variance inflation factors, the Akaike information criterion, and R2 to compare the results of different models. RESULTS: Results were obtained for 420 individuals (53% boys) with a mean age of 11.7 ± 4.5 standard deviation (SD) years; 47% of maneuvers from children age 4-6 years were grade A (13% grade B), and 90% of those in children older than 13 years were grade A or B. Forty-six percent of the subjects had a DlCOsb repeatability of <1 ml/min/mm Hg. The mean DlCOsb was higher for boys than for girls (32.4 ± 13.6 [SD] vs. 24.1 ± 7.5 ml/min/mm Hg, respectively). The reference equation for boys was DlCOsb = exp(1.63469 + [0.03251 × age] + [0.00846 × height] + [0.00304 × weight]), R2 = 0.87; for girls, the best equation was DlCOsb = exp(1.56516 + [0.0193 × age] + [0.00893 × height] + [0.00273 × weight]), R2 = 0.75. The single-breath transfer coefficient of the lung for carbon monoxide remained constant with age and height, with a lower limit of normal of 6.5 ml/min/mm Hg/L in boys and 5.4 ml/min/mm Hg/L in girls. Measured DlCOsb was higher than predicted by other authors (P < 0.001 by paired t test). CONCLUSIONS: Individuals 4-20 years of age can complete high-quality DlCOsb tests. Children and adolescents living at 2,240 m have higher DlCOsb values than those living at sea level. Reference equations for DlCOsb obtained at sea level are poor predictors of the values measured at moderate altitude.

Longitudinal Evaluation of Lung Function in Patients With Advanced Non-Small Cell Lung Cancer Treated With Concurrent Chemoradiation Therapy.

PURPOSE: In lung cancer patients, radiation therapy modifies lung architecture, resulting in functional deterioration, which worsens symptoms and reduces quality of life. METHODS AND MATERIALS: A multicenter, prospective, longitudinal study was conducted in a cohort of patients with locally advanced and oligometastatic non-small cell lung cancer treated with concurrent chemoradiation therapy (CCRT). A wide array of pulmonary function tests (forced spirometry, body plethysmography, impulse oscillometry, carbon monoxide diffusing capacity, fraction of exhaled nitric oxide, arterial blood gases, and 6-minute walk test) were used to evaluate lung function at baseline; after radiation therapy; and at 6, 12, 24, and 48 weeks after CCRT. Relative changes in test results (percentages) were estimated at the aforementioned intervals and compared with baseline results. RESULTS: Thirty-seven patients completed the follow-up and were included in the analysis. After CCRT, patients showed a maximum decline in lung volumes as follows: (1) 31% in forced expiratory volume in the first second after 24 weeks (P = .008), (2) 9.6% in forced vital capacity after 48 weeks (P = .04), and (3) 15.1% in total lung capacity after 48 weeks (P = .0015). Similarly, at 12 weeks after CCRT, patients showed a 21.8% decrease in carbon monoxide diffusing capacity (P = .002). Increases were found in total airway resistance (respiratory system resistance at 5 Hz), frequency dependence of resistance (change in respiratory system resistance at 5 Hz-respiratory system resistance at 20 Hz, P = .012), and reactance (P = .0003 for respiratory system reactance at 5 Hz and P = .001 for reactance area), which together indicate small-airway dysfunction. CONCLUSIONS: The longitudinal evaluation of lung function through pulmonary function tests detects CCRT-induced damage before the appearance of clinical symptoms associated with CCRT lung toxicity.

Th-17 cytokines are associated with severity of Trypanosoma cruzi chronic infection in pediatric patients from endemic areas of Mexico.

In Chagas disease the clinical, acute and chronic manifestations are the result of the interaction between the parasite and the host factors. The balance between inflammatory and anti-inflammatory immune responses is essential for the increase or resolution of the manifestations in individuals infected with T. cruzi. To identify if children with chronic Chagas disease and heart injury is related with non-regulated Th1, Th2 and Th17 responses. We included 31 children with T. cruzi confirmed chronic infection from endemic areas of Mexico. Subsequently, they were separated according to their ECHO and ECG results into three groups according to the severity of cardiac involvement. Circulating Th1, Th2 and Th17 cytokine profiles were performed by Luminex assays and the results were analyzed by bivariate and multivariable analysis. Patients were classified in asymptomatic chronic (group 1, N=12); individuals with IRBBB in ECG and incipient lesions in ECHO (Group 2, N=8) and Patients with severe chronic symptomatic disease (Group 3, N=11). The analysis of immune mediators revealed that patients with severe cardiac manifestations had significant higher levels (p <0.05) of Th17 related cytokines including IL-17 and IL-6 as well as IFN-γ and IL-2. Also patients with severe cardiomyopathy exhibit increased levels of IL-13 (p <0.05) after multivariate analysis. High levels of Th17 related cytokines including IL-17, IFN-γ, IL-6 and IL-2 and pro-fibrotic factors such as IL-13 could be associated to the severity of cardiac involvement in children with chronic T. cruzi infection. These cytokines could be useful as indicators for the early identification of cardiac damage associated to the T. cruzi infection.

Validating Reference Equations for Impulse Oscillometry in Healthy Mexican Children.

BACKGROUND: The impulse oscillometry system (IOS) measures the impedance (Z) of the respiratory system, but proper interpretation of its results requires adequate reference values. The objectives of this work were: (1) to validate the reference equations for the IOS published previously by our group and (2) to compare the adjustment of new available reference equations for the IOS from different countries in a sample of healthy children. METHODS: Subjects were healthy 4-15-y-old children from the metropolitan area of Mexico City, who performed an IOS test. The functional IOS parameters obtained were compared with the predicted values from 12 reference equations determined in studies of different ethnic groups. The validation methods applied were: analysis of the differences between measured and predicted values for each reference equation; correlation and concordance coefficients; adjustment by Z-score values; percentage of predicted value; and the percentage of patients below the lower limit of normality or above the upper limit of normality. RESULTS: Of the 224 participants, 117 (52.3%) were girls, and the mean age was 8.6 ± 2.3 y. The equations that showed the best adjustment for the different parameters were those from the studies by Nowowiejska et al (2008) and Gochicoa et al (2015). The equations proposed by Frei et al (2005), Hellinckx et al (1998), Kalhoff et al (2011), Klug and Bisgaard (1998), de Assumpção et al (2016), and Dencker et al (2006) overestimated the airway resistance of the children in our sample, whereas the equation of Amra et al (2008) underestimated it. In the analysis of the lower and upper limits of normality, Gochicoa et al equation was the closest, since 5% of subjects were below or above percentiles 5 and 95, respectively. The study found that, in general, all of the equations showed greater error at the extremes of the age distribution. CONCLUSIONS: Because of the robust adjustment of the present study reference equations for the IOS, it can be recommended for both clinical and research purposes in our population. The differential adjustment of other equations underlines the need to obtain local reference values.

La diabetes se asocia con reacciones adversas graves en la tuberculosis multirresistente / Diabetes is Associated with Severe Adverse Events in Multidrug-Resistant Tuberculosis

Introducción: La diabetes mellitus (DM), una enfermedad muy frecuente en México, es un factor de riesgo bien conocido para el desarrollo de tuberculosis (TB). Sin embargo, se desconoce en qué medida la DM predispone al desarrollo de reacciones adversas (RA) a los fármacos anti-tuberculosis y/o si predispone a un peor resultado en pacientes con pacientes con TB multirresistente (TB-MR) y TB extremadamente resistente (TB-XR). El objetivo principal de este estudio fue describir los resultados del tratamiento anti-tuberculosis, el impacto de la DM y la prevalencia de RA en una cohorte de pacientes con TB pulmonar MR/XR tratados en el centro de referencia nacional para TB, en la Ciudad de México. Resultados: Entre 2010 y 2015 se incluyeron 90 pacientes -73 con TB-MR (81,1%), 11 con TB pre-XR (12,2%) y 6 (6,7%) con TB-XR-, 49 (54,4%) de los cuales tenían DM y 3 con co-infección por el virus de la inmunodeficiencia humana (VIH) (3,3%). El diagnóstico se realizó mediante cultivo y pruebas de fármaco-sensibilidad (PFS) en el 98% de los pacientes y mediante prueba molecular en un caso. La presencia de DM se asoció con un mayor riesgo de RA graves, tales como nefrotoxicidad (odds ratio [OR] = 6,5; intervalo de confianza del 95% [IC 95%]: 1,9-21,8) e hipotiroidismo (OR = 8,8; IC 95%: 1,8-54,2), aunque no con peor resultado del tratamiento. onclusiones: Nuestros datos sugieren que la DM no tiene un impacto sobre los resultados del tratamiento anti-tuberculosis de segunda línea, pero los pacientes con DM tienen mayor riesgo de presentar RA graves secundarias al tratamiento, tales como nefrotoxicidad e hipotiroidismo

Introduction: Diabetes mellitus (DM), a very common disease in Mexico, is a well-known risk factor for tuberculosis (TB). However, it is not known by which extent DM predisposes to adverse events (AE) to anti-TB drugs and/or to worse outcomes in patients with multidrug-resistant (MDR-TB) and extensively drug-resistant TB (XDR-TB). The main objective of this study was to describe the outcomes of TB treatment, the impact of DM and the prevalence of AE in a cohort of patients with MDR-/XDR pulmonary TB treated at the national TB referral centre in Mexico City. Results: Ninety patients were enrolled between 2010 and 2015: 73 with MDR-TB (81.1%), 11 with pre-XDR-TB (12.2%) and 6 (6.7%) with XDR-TB, including 49 (54.4%) with DM, and 3 with Human Immunodeficiency Virus (HIV) co-infection (3.3%). In 98% of patients, diagnosis was made by culture and drug susceptibility testing, while in a single case the diagnosis was made by a molecular test. The presence of DM was associated with an increased risk of serious drug-related AEs, such as nephrotoxicity (Odds Ratio [OR] = 6.5; 95% Confidence Interval [95% CI]: 1.9-21.8) and hypothyroidism (OR = 8.8; 95% CI: 1.8-54.2), but not for a worse outcome. Conclusions: Our data suggest that DM does not impact second-line TB treatment outcomes, but patients with DM have a higher risk of developing serious AEs to drug-resistant TB treatment, such as nephrotoxicity and hypothyroidism

[Inpatients days in patients with respiratory diseases and periodontal disease]. / Días de estancia hospitalaria (DEH) en pacientes con enfermedades respiratorias (ER) y enfermedad periodontal (EP).

INTRODUCTION: Periodontal disease is a chronic inflammatory gingival process that has been associated with the severity of respiratory diseases. In Mexico a prevalence of 78% was found in population with social security and > 60 years old. The aim of this study is to establish the association between periodontal disease and respiratory diseases according to the inpatient days. MATERIAL AND METHODS: A cross-sectional study was conducted from January to December 2011. We included hospitalized patients, ≥ 18 years of age, without sedation or intubated. A dentist classified patients into two groups according to the severity of the periodontal disease: mild-to-moderate and severe. We estimated medians of inpatient days by disease and severity. Negative binomial models were adjusted to estimate incidence rate ratios and predicted inpatient days. RESULTS: 3,059 patients were enrolled. The median of observed and predicted inpatient days was higher in the group of severe periodontal disease (p < 0.05). Patients with chronic obstructive pulmonary disease, tuberculosis, and influenza had the highest incidence rates ratios of periodontal disease (p < 0.05). CONCLUSIONS: The severity of periodontal disease is positively -associated with inpatient days of patients with respiratory diseases.

Diabetes is Associated with Severe Adverse Events in Multidrug-Resistant Tuberculosis. / La diabetes se asocia con reacciones adversas graves en la tuberculosis multirresistente.

INTRODUCTION: Diabetes mellitus (DM), a very common disease in Mexico, is a well-known risk factor for tuberculosis (TB). However, it is not known by which extent DM predisposes to adverse events (AE) to anti-TB drugs and/or to worse outcomes in patients with multidrug-resistant (MDR-TB) and extensively drug-resistant TB (XDR-TB). The main objective of this study was to describe the outcomes of TB treatment, the impact of DM and the prevalence of AE in a cohort of patients with MDR-/XDR pulmonary TB treated at the national TB referral centre in Mexico City. RESULTS: Ninety patients were enrolled between 2010 and 2015: 73 with MDR-TB (81.1%), 11 with pre-XDR-TB (12.2%) and 6 (6.7%) with XDR-TB, including 49 (54.4%) with DM, and 3 with Human Immunodeficiency Virus (HIV) co-infection (3.3%). In 98% of patients, diagnosis was made by culture and drug susceptibility testing, while in a single case the diagnosis was made by a molecular test. The presence of DM was associated with an increased risk of serious drug-related AEs, such as nephrotoxicity (Odds Ratio [OR]=6.5; 95% Confidence Interval [95% CI]: 1.9-21.8) and hypothyroidism (OR=8.8; 95% CI: 1.8-54.2), but not for a worse outcome. CONCLUSIONS: Our data suggest that DM does not impact second-line TB treatment outcomes, but patients with DM have a higher risk of developing serious AEs to drug-resistant TB treatment, such as nephrotoxicity and hypothyroidism.

Effect of Passive Smoking on the Growth of Pulmonary Function and Respiratory Symptoms in Schoolchildren.

BACKGROUND: Environmental tobacco smoke affects the current and future health of children. OBJECTIVE: To determine whether schoolchildren aged 8-17 years old residing at an altitude of 2,240 m and exposed to tobacco smoke at home presented a reduction in the growth of pulmonary function and a greater problem of respiratory symptoms and infections compared with non-exposed children. MATERIALS AND METHODS: We followed, with questionnaires and spirometry, 1,632 boys and 1,555 girls from Mexico City and its metropolitan area (the Metropolitan Study to Evaluate the Chronic Effects of Pollution in School-age Children [EMPECE]) every six months for six years. The impact of passive smoking was estimated by mixed-effects models and Generalized Linear and Latent Mixed Models (GLLAMM), stratifying by gender and adjusting for age, height, weight, and ozone levels. RESULTS: Passive smoking (reported by one-half of participants) was associated with reduced spirometric lung function (log transformed or as Z-scores) and a higher frequency of self-reported respiratory symptoms and respiratory infections. Levels of forced expiratory volume in 1 second and forced vital capacity in individuals exposed to passive smoking were 6.8 and 14.1 ml, respectively, below those of non-exposed children, and these values decreased with increasing number of smokers at home and higher ozone levels. CONCLUSIONS: Passive smoking in children is a significant risk factor for respiratory disease and reduced lung function growth, which are additive with levels of air pollution, asthma, and the presence of respiratory symptoms.

[Prevalence of severe periodontal disease and its association with respiratory disease in hospitalized adult patients in a tertiary care center]. / Prevalencia de enfermedad periodontal grave (EPG) y su asociación con enfermedades respiratorias en pacientes adultos hospitalizados en un centro de tercer nivel.

BACKGROUND: Severe periodontal disease is a chronic inflammatory gingival process associated with systemic diseases. OBJECTIVE: To determine the prevalence of severe periodontal disease and its association with respiratory diseases among hospitalized patients at the Institute of Respiratory Diseases "Ismael Cosio Villegas" (INER) in 2011. MATERIAL AND METHODS: A cross-sectional study was developed. The severe periodontal disease was diagnosed by the Department of Stomatology. The International Classification of Diseases 10th revision was used. A multinomial logistic was fit to estimate relative-risk. RESULTS: Three thousand and fifty-nine patients were included; 772/3,059 (25.2%) had severe periodontal disease. After controlling for age, sex, inpatient days, death, and socioeconomic status, the infectious respiratory diseases that were significantly associated with severe periodontal disease were: HIV/AIDS (RR: 10.6; 95% CI: 9.1-23.3; p < 0.0001); pneumonia (RR: 2.6; 95% CI: 2.2-5.7; p < 0.0001); pulmonary tuberculosis and its sequels (RR: 2.1; 95% CI: 1.6-4.9; p < 0.0001); and lung abscess (RR: 2.6; 95% CI: 1.6-7.8; p = 0.002). Lung cancer and pleural diseases were also significantly associated with severe periodontal disease. CONCLUSIONS: High prevalence of severe periodontal disease was observed in the different respiratory diseases. Severe periodontal disease was associated with both infectious and non-infectious respiratory diseases. It is important to study an oral health intervention.

Socioeconomic Status and Longitudinal Lung Function of Healthy Mexican Children.

INTRODUCTION: Our aim was to estimate the longitudinal effect of Socioeconomic status (SES) on lung function growth of Mexican children and adolescents. MATERIALS AND METHODS: A cohort of Mexican children in third grade of primary school was followed with spirometry twice a year for 6 years through secondary school. Multilevel mixed-effects lineal models were fitted for the spirometric variables of 2,641 respiratory-healthy Mexican children. Monthly family income (in 2002 U.S. dollars [USD]) and parents' years completed at school were used as proxies of SES. RESULTS: Individuals with higher SES tended to have greater height for age, and smaller sitting height/standing height and crude lung function. For each 1-year increase of parents' schooling, Forced expiratory volume in 1 sec (FEV1) and Forced vital capacity (FVC) increased 8.5 (0.4%) and 10.6 mL (0.4%), respectively (p <0.05) when models were adjusted for gender. Impact of education on lung function was reduced drastically or abolished on adjusting by anthropometric variables and ozone. CONCLUSIONS: Higher parental schooling and higher monthly family income were associated with higher lung function in healthy Mexican children, with the majority of the effect likely due to the increase in height-for-age.

Efficient screening for COPD using three steps: a cross-sectional study in Mexico City.

BACKGROUND: Underdiagnosis of chronic obstructive pulmonary disease (COPD) in primary care can be improved by a more efficient screening strategy. AIMS: To evaluate a three-step method of screening for COPD consisting of an initial short questionnaire followed by measurement of forced expiratory volume in 1s/forced expiratory volume in 6s (FEV1/FEV6) using an inexpensive pocket spirometer in those with high risk, and diagnostic quality spirometry in those with a low FEV1/FEV6. METHODS: We analysed two related Mexico City cross-sectional samples. The 2003 Mexico City PLATINO survey (n=542) was used to develop a short questionnaire to determine the risk of COPD and a 2010 survey (n=737) additionally used a pocket spirometer. The discriminatory power of the two instruments was assessed with receiver operator characteristic (ROC) curves using three COPD definitions. RESULTS: The developed COPD scale included two variables from a simple questionnaire and, in ROC analysis, an area under the curve (AUC) between 0.64 and 0.77 was found to detect COPD. The pocket spirometer had an AUC between 0.85 and 0.88 to detect COPD. Using the COPD scale as a first screening step excluded 35-48% of the total population from further testing at the cost of not detecting 8-18% of those with COPD. Using the pocket spirometer and sending those with a FEV1/FEV6<0.80 for diagnostic quality spirometry is very efficient, and substantially improved the positive predictive value at the cost of not detecting one-third of COPD cases. CONCLUSIONS: A three-step screening strategy for COPD substantially reduces the need for spirometry testing when only a COPD scale is used for screening.

Longitudinal lung function growth of Mexican children compared with international studies.

INTRODUCTION: Our aim was to compare the longitudinal lung function growth of Mexican children and adolescents with the collated spirometric reference proposed for international use and with that of Mexican-Americans from the National Health State Examination Survey III (NHANES) III study. MATERIALS AND METHODS: A cohort of Mexican children in third year of primary school was followed with spirometry twice a year through secondary school. Multilevel mixed-effects lineal models separated by gender were fit for the spirometric variables of 2,641 respiratory-healthy Mexican children expressed as Z-scores of tested reference equations. Impact of adjustment by sitting height on differences with Mexican-American children was observed in a subsample of 1,987 children. RESULTS: At same gender, age, and height, Mexican children had increasingly higher forced expiratory volume in 1 s (FEV1) and Forced vital capacity (FVC) than the children from the collated reference study (mean Z-score, 0.68 for FEV1 and 0.51 for FVC) and than Mexican-American children (Z-score, 0.23 for FEV1 and 0.21 for FVC) respectively. Differences with Mexican-Americans were not reduced by adjusting by sitting height. CONCLUSIONS: For reasons that remain unclear, the gender-, age-, and height-adjusted lung function of children from Mexico City is higher than that reported by several international studies.

Perceptions of short and long sleep duration and comorbid conditions: the PLATINO study.

OBJECTIVES: We aimed to describe the distribution of self-reported sleep duration in adults over the age of 40 years and to analyze the associated risk factors, comorbid conditions, and quality of life (QoL). METHODS: Our study was constructed as a cross-sectional population-based study and is part of the PLATINO (Spanish acronym for the Latin American Project for Research in Pulmonary Obstruction) study. It includes data from Mexico City (Mexico), Montevideo (Uruguay), Santiago (Chile), and Caracas (Venezuela). Data from 4533 individuals were analyzed using a single questionnaire entitled, PLATINO, which was designed to collect data on self-reported sleep symptoms. Spirometry also was performed in accordance with international standards. All statistical analyses took the study design into consideration with adjustments for each city. RESULTS: The prevalence of subjects who reported sleeping <7h was 38.4%, ≥ 7 to <9h was 51.4%, and ≥ 9h was 10.2%. In the multivariate analysis, individuals with shorter sleep duration had higher frequencies of insomnia, increased forced expiratory volume in one second in liters and percentage/forced vital capacity in liters (FEV1/FVC) of predicted ratios, and a higher presence of coughing and phlegm. The main risk factor associated with longer duration of sleep was the number of comorbidities. CONCLUSIONS: Self-reported sleep duration discriminated among groups that differed in sleep-related symptoms, respiratory symptoms, QoL and comorbid conditions.

The impact of altitude on hospitalization and hospital mortality from pandemic 2009 influenza A (H1N1) virus pneumonia in Mexico.

OBJECTIVE: To determine the effect of altitude of residence on influenza A (H1N1). MATERIALS AND METHODS: We analyzed 207 135 officially notified of influenza-like illness (ILI) cases, 23 048 hospitalizations and 573 deaths during the first months of the novel pandemic influenza A H1N1 virus, to examine if residents of high altitude had more frequently these adverse outcomes. RESULTS: Adjusted rates for hospitalization and hospital mortality rates increased with altitude, probably due to hypoxemia.

The impact of altitude on hospitalization and hospital mortality from pandemic 2009 influenza A (H1N1) virus pneumonia in Mexico / El impacto de la altitud en las tasas de hospitalización y mortalidad por el virus de la influenza A (H1N1) pandémico en México

OBJECTIVE: To determine the effect of altitude of residence on influenza A (H1N1). MATERIALS AND METHODS: We analyzed 207 135 officially notified of influenza-like illness (ILI) cases, 23 048 hospitalizations and 573 deaths during the first months of the novel pandemic influenza A H1N1 virus, to examine if residents of high altitude had more frequently these adverse outcomes. RESULTS: Adjusted rates for hospitalization and hospital mortality rates increased with altitude, probably due to hypoxemia.

OBJETIVO: Determinar el efecto de la altitud del lugar de residencia sobre la epidemia de influenza A (H1N1). MATERIAL Y MÉTODOS: Se analizaron 207 135 casos notificados a la Secretaría de Salud, 23 048 hospitalizaciones y 573 muertes por enfermedad similar a la influenza (ILI, por sus siglas en inglés) durante los primeros meses de la pandemia del nuevo virus de la influenza A H1N1 durante 2009, para examinar si los residentes de zonas más altas presentaron tasas más altas de hospitalización y muerte. RESULTADOS: Las tasas ajustadas de hospitalización y mortalidad hospitalaria se incrementaron con la altitud probablemente por la presencia de hipoxemia.

Prevalencia y riesgos asociados con pacientes adultos con asma de 40 años o más de la Ciudad de México: estudio de base poblacional / Adult asthma in Mexico City: a population-based study

OBJETIVOS: Determinar la prevalencia de asma y la asociación entre características sociodemográficas, espirométricas, síntomas respiratorios, calidad de vida y sueño en adultos >40 años. MATERIAL Y MÉTODOS: Este informe es parte del estudio PLATINO (Proyecto Latinoamericano de Investigación en Obstrucción Pulmonar), llevado a cabo en la Ciudad de México y área metropolitana en 2003. Se utilizaron modelos de regresión logística ajustados por el diseño del estudio, donde asma fue la variable dependiente y las independientes síntomas respiratorios y características sociodemográficas y clínicas, entre otras. RESULTADOS: La prevalencia de asma diagnosticada por médico fue de 3.3% en hombres y 6.2% en mujeres. La función pulmonar disminuyó en asmáticos. En el análisis multivariado, después de ajustar por confusores potenciales, los asmáticos mostraron un mayor riesgo de ronquido más somnolencia excesiva diurna [RM=3.2 (IC95%1.4-7.4), p=0.008], y mayor frecuencia de inasistencias laborales por problemas respiratorios [RM=5.1 (IC95% 2.5-10.4), p<0.0001]. CONCLUSIONES: La prevalencia de asma fue de 5%. Los asmáticos mostraron menor calidad de vida y función pulmonar.

OBJECTIVES: To determine the prevalence of asthma and the association between sociodemographic characteristics, spirometry, respiratory symptoms, quality of life and sleep in adults > 40 years. MATERIALS AND METHODS: This report is part of our study (Latin American Research Project Obstructive Pulmonary), held in Mexico City and the metropolitan area in 2003. We used logistic regression models adjusted for study design, where asthma was the dependent and independent variable respiratory symptoms, sociodemographic and clinical characteristics among others. RESULTS: The prevalence of physician-diagnosed asthma was: 3.3% in men and 6.2% in women. Decreased lung function in asthmatics was observed. In multivariate analysis, after adjusting for potential confounders, asthmatics had a higher risk of excessive daytime sleepiness more snoring [OR = 3.2 (95% CI 1.4-7.4), p= 0.008], and more frequent work absences due to respiratory problems [OR = 5.1 (95% CI 2.5-10.4), p<0.0001]. CONCLUSIONS: The prevalence of asthma was 5%. Asthmatics showed lower quality of life and lung function.

[Adult asthma in Mexico City: a population-based study]. / Prevalencia y riesgos asociados con pacientes adultos con asma de 40 años o más de la Ciudad de México: estudio de base poblacional.

OBJECTIVES: To determine the prevalence of asthma and the association between sociodemographic characteristics, spirometry, respiratory symptoms, quality of life and sleep in adults > 40 years. MATERIALS AND METHODS: This report is part of our study (Latin American Research Project Obstructive Pulmonary), held in Mexico City and the metropolitan area in 2003. We used logistic regression models adjusted for study design, where asthma was the dependent and independent variable respiratory symptoms, sociodemographic and clinical characteristics among others. RESULTS: The prevalence of physician-diagnosed asthma was: 3.3% in men and 6.2% in women. Decreased lung function in asthmatics was observed. In multivariate analysis, after adjusting for potential confounders, asthmatics had a higher risk of excessive daytime sleepiness more snoring [OR = 3.2 (95% CI 1.4-7.4), p= 0.008], and more frequent work absences due to respiratory problems [OR = 5.1 (95% CI 2.5-10.4), p<0.0001]. CONCLUSIONS: The prevalence of asthma was 5%. Asthmatics showed lower quality of life and lung function.

Demand for care and nosocomial infection rate during the first influenza AH1N1 2009 virus outbreak at a referral hospital in Mexico City.

OBJECTIVE: Comparison of routine hospital indicators (consults at the Emergency Room (ER) and hospital admissions) during the 2009 pandemic of the influenza AH1N1 virus at the national referral hospital for respiratory diseases in Mexico City. MATERIAL AND METHODS: The outbreak was from April to mid-May 2009 and two control periods were used:2009 (before and after the outbreak),and during April-May from 2007 and 2008. RESULTS: During the outbreak total consultation at the ER increased six times compared with the 2007-2008 control period and 11 times compared with the 2009 control period. Pneumonia- or influenza-related ER consultations increased 23.2 and 15.3%, respectively. The rate of nosocomial infection during the outbreak was 13.6 and that of nosocomial pneumonia was 6 per/100 hospital discharges, a two-fold and three-fold increase compared to the control periods respectively. CONCLUSIONS: During the outbreak,mean severity of admitted patients increased,with a rise in in-hospital mortality and nosocomial infections rate, including nosocomial pneumonia.