Smoking exposure trajectories and pulmonary function in early adulthood in a Brazilian cohort.

OBJECTIVES: To investigate smoking trajectories and their association with pulmonary function (PF) and respiratory symptoms at age 22. METHODS: Data from a population-based cohort study of 3350 individuals and their spirometries were analysed. The outcomes were: forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), forced expiratory flow at the mid expiratory phase (FEF25-75 %), FEV1/FVC and FEF25-75/FVC ratio. Smoking data were collected at perinatal follow-up (gestational exposure) and 15, 18 and 22 years. Group-based trajectory model was applied. RESULTS: Four groups were identified: no exposure (NE), gestational (GE), gestational and adulthood (GAE) and continuous (CE) exposure. Both CE and GAE trajectories were associated with lower values of FEV1/FVC (-1.77pp; p = 0.01 and -1.58 pp; p<0.001 respectively) and FEF25-75/FVC ratio (-7.27pp; p = 0.019 and -6.04pp; p<0.001 respectively) compared to the NE trajectory. Lower FEV1 and FEF25-75 % values were also related to the GAE trajectory (-68 ml; p = 0.03 and -253 ml/s;p<0.001 respectively). Compared to those who never smoked, individuals who smoked 10 or more cigarettes daily presented a reduction in the FEV1/FVC ratio by 1.37pp (p<0.001), FEF25-75 % by 126 ml (p = 0.012) and FEF25-75 %/FVC ratio by 3.62pp (p = 0.011). CE trajectory showed higher odds of wheezing (OR 4.14; p<0.001) and cough (OR 2.39; p = 0.002) compared to the non-exposed group. CONCLUSIONS: The in-uterus exposure to maternal smoking reduces PF later in life. However, the perpetuation of smoking behaviour throughout adolescence and early adulthood is determinant for PF main reduction and the emergence of respiratory-related symptoms.

Household air pollution and COPD: cause and effect or confounding by other aspects of poverty?

SETTING: Household air pollution (HAP) and chronic obstructive pulmonary disease (COPD) are both major public health problems, reported to cause around 4 million and 3 million deaths every year, respectively. The great majority of these deaths, as well as the burden of disease during life is felt by people in low- and middle-income countries (LMICs).OBJECTIVE and DESIGN: The extent to which HAP causes COPD is controversial; we therefore undertook this review to offer a viewpoint on this from the Global Initiative for COPD (GOLD).RESULTS: We find that while COPD is well-defined in many studies on COPD and HAP, there are major limitations to the definition and measurement of HAP. It is thus difficult to disentangle HAP from other features of poverty that are themselves associated with COPD. We identify other limitations to primary research studies, including the use of cross-sectional designs that limit causal inference.CONCLUSION: There is substantial preventable morbidity and mortality associated with HAP, COPD and poverty, separately and together. Although it may not be possible to define clear causal links between HAP and COPD, there is a clear urgency to reduce the avoidable burden of disease these inflict on the world´s poor.

Functional impact of sequelae in drug-susceptible and multidrug-resistant tuberculosis.

BACKGROUND: Evidence on the impact of tuberculosis (TB) treatment on lung function is scarce. The aim of this study was to evaluate post-treatment sequelae in drug-susceptible and drug-resistant-TB (DR-TB) cases in Mexico and Italy.METHODS: At the end of TB treatment the patients underwent complete clinical assessment, functional evaluation of respiratory mechanics, gas exchange and a 6-minute walking test. Treatment regimens (and definitions) recommended by the World Health Organization were used throughout.RESULTS: Of 61 patients, 65.6% had functional impairment, with obstruction in 24/61 patients (39.4%), and 78% with no bronchodilator response. These effects were more prevalent among DR-TB cases (forced expiratory volume in 1 s/forced vital capacity [FEV1/FVC] < lower limit of normality, 14/24 vs. 10/34; P = 0.075). DR-TB patients showed moderately severe (FEV1 < 60%) and severe obstruction (FEV1 < 50%) (P = 0.008). Pre- and post-bronchodilator FEV1 and FEV1/FVC (% of predicted) were significantly lower among DR-TB cases. Plethysmography abnormalities (restriction, hyperinflation and/or air trapping) were more frequent among DR-TB cases (P = 0.001), along with abnormal carbon monoxide diffusing capacity (DLCO) (P = 0.003).CONCLUSION: The majority of TB patients suffer the consequences of post-treatment sequelae (of differing levels), which compromise quality of life, exercise tolerance and long-term prognosis. It is therefore important that lung function is comprehensively evaluated post-treatment to identify patient needs for future medication and pulmonary rehabilitation.

Comparison of bacteriological conversion and treatment outcomes among MDR-TB patients with and without diabetes in Mexico: Preliminary data.

Diabetes mellitus (DM) is a well-known risk factor for tuberculosis (TB). However, it is not known to what extent DM affects the outcome in patients with multidrug-resistant (MDR-TB) and extensively drug-resistant TB (XDR-TB) treated with second-line anti-TB drugs. The objective of this study was to compare the microbiological evolution (sputum smear and culture conversion) and final outcomes of MDR/XDR-TB patients with and without DM, managed at the national TB reference centre in Mexico City. RESULTS: Ninety patients were enrolled between 2010 and 2015: 73 with MDR-TB (81.1%), 11 with pre-XDR-TB (e.g. MDR-TB with additional resistance to one injectable drug or a fluoroquinolone, 12.2%) and 6 (6.7%) with XDR-TB. Out of these, 49 (54.4%) had DM and 42 (86%) were undergoing insulin treatment. No statistically significant differences were found in treatment outcomes comparing DM vs. non-DM MDR-TB cases: 18/32 (56.3%) of DM cases and 19/24 (79.2%) non DM patients achieved treatment success (p=0.07). The time to sputum smear and culture conversion was longer (although not statistically) in patients without DM, as follows: the mean (±SD) time to sputum smear conversion was 53.9 (±31.4) days in DM patients and 65.2 (±34.8) days in non-DM ones (p=0.15), while the time to culture conversion was 66.2 (±27.6) days for DM and 81.4 (±37.7) days for non-DM MDR-TB cases (p=0.06). CONCLUSIONS: The study results support the Mexican National TB programme to strengthen its collaboration with the DM programme, as an entry point for TB (and latent TB infection) screening and management.

The global burden of chronic respiratory disease in adults.

With an aging global population, chronic respiratory diseases are becoming a more prominent cause of death and disability. Age-standardised death rates from chronic obstructive pulmonary disease (COPD) are highest in low-income regions of the world, particularly South Asia and sub-Saharan Africa, although airflow obstruction is relatively uncommon in these areas. Airflow obstruction is, by contrast, more common in regions with a high prevalence of cigarette smoking. COPD mortality is much more closely related to the prevalence of a low forced vital capacity which is, in turn, associated with poverty. Mortality from asthma is less common than mortality from COPD, but it is also relatively more common in poorer areas, particularly Oceania, South and South-East Asia, the Middle East and Africa. Again this contrasts with the asthma prevalence among adults, which is highest in high-income regions. In high-income areas, mortality due to asthma, which is predominantly an adult problem, has fallen substantially in recent decades with the spread of new guidelines for treatment that emphasise the use of inhaled steroids to control the disease. Although mortality rates have been falling, the prevalence of atopy has been increasing between generations in Western Europe. Changes in the prevalence of wheeze among adults has been more varied and may have been influenced by the reduction in smoking and the increase in the use of inhaled steroids.

Summarising published results from spirometric surveys of COPD: the problem of inconsistent definitions.

SETTING: The use of different spirometric definitions for chronic obstructive pulmonary disease (COPD) has made an informative review of the available prevalence surveys impossible. OBJECTIVE: To derive adjustment factors that allow the comparison of studies using different spirometric criteria. METHODS: Pre- and post-bronchodilator one-second forced expiratory volume (FEV1) and forced vital capacity (FVC) values were taken from the Burden of Obstructive Lung Disease (BOLD) survey in 16 centres. Using a post-bronchodilator FEV1/FVC ratio less than the lower limit of normal (LLN) as our reference prevalence, we calculated simple multiplicative adjustments to transform other reported prevalence estimates to reference values. These adjustments were then tested on independent data sets from six further BOLD centres and five centres from the PLATINO study, a Latin American survey on obstructive lung disease. RESULTS: Prevalence estimates based on pre-bronchodilator fixed-ratio measurements were 5-25% higher than reference values, and were strongly positively biased with age and prevalence level. Applying simple adjustments provided prevalence estimates that were almost unbiased and within 5% of the reference values. CONCLUSIONS: Using the BOLD data, we have been able to estimate COPD prevalences based on post-bronchodilator FEV1/FVC < LLN by adjusting estimates based on other common definitions, enabling more meaningful comparisons of published findings.

Paid employment in subjects with and without chronic obstructive pulmonary disease in five Latin American cities: the PLATINO study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a costly condition that frequently causes permanent work disabilities. Little information exists regarding the impact of COPD on work force participation and the indirect costs of the disease in developing countries. OBJECTIVE: To examine the frequency of paid employment and factors influencing it in a Latin-American population-based study. METHODS: Post-bronchodilator FEV(1)/FVC < 0.70 (forced expiratory volume in 1 s/forced vital capacity) was used to define COPD. Information regarding paid work was assessed by the question 'At any time in the past year, have you worked for payment?' RESULTS: Interviews were conducted with 5571 subjects; 5314 (759 COPD and 4554 non-COPD) subjects underwent spirometry. Among the COPD subjects, 41.8% reported having paid work vs. 57.1% of non-COPD (P < 0.0001). The number of months with paid work was reduced in COPD patients (10.5 ± 0.17 vs. 10.9 ± 0.06, P < 0.05). The main factors associated with having paid work in COPD patients were male sex (OR 0.33, 95%CI 0.23-0.47), higher education level (OR 1.05, 95%CI 1.01-1.09) and younger age (OR 0.90, 95%CI 0.88-0.92). COPD was not a significant contributor to employment (OR 0.83, 95%CI 0.69-1.00, P = 0.054) in the entire population. CONCLUSIONS: Although the proportion of persons with paid work is lower in COPD, having COPD appears not to have a significant impact on obtaining paid employment in the overall population of developing countries.

Respiratory health effects of indoor air pollution.

Domestic pollution is relevant to health because people spend most of their time indoors. One half of the world's population is exposed to high concentrations of solid fuel smoke (biomass and coal) that are produced by inefficient open fires, mainly in the rural areas of developing countries. Concentrations of particulate matter in kitchens increase to the range of milligrams per cubic meter during cooking. Solid fuel smoke possesses the majority of the toxins found in tobacco smoke and has also been associated with a variety of diseases, such as chronic obstructive pulmonary disease in women, acute respiratory infection in children and lung cancer in women (if exposed to coal smoke). Other tobacco smoke-associated diseases, such as tuberculosis, asthma, respiratory tract cancer and interstitial lung diseases, may also be associated with solid fuel smoke inhalation, but evidence is limited. As the desirable change to clean fuels is unlikely, efforts have been made to use efficient, vented wood or coal stoves, with varied success due to inconsistent acceptance by the community.

Frequency of adverse events and mortality in patients with pleural empyema in a public referral hospital in Mexico City.

SETTING: Adverse events (AEs) that occur during medical treatment are a public health problem. OBJECTIVE: 1) To measure the prevalence of AEs, 2) to characterize those that occur in patients diagnosed with empyema and 3) to analyze the mortality rate associated with the presence of empyema. DESIGN: Retrospective case series based on a review of files of patient diagnosed with empyema. RESULTS: A total of 347 files were assessed, reporting 96.6% of the total number of patients diagnosed with empyema in that period. There were 176 AEs reported for 150 of the patients. The frequency of at least one AE was 43%, with prolonged hospitalization being the most frequent condition. In these cases, 97% of the AEs were considered preventable. Intrahospital mortality was 4.8%, with age (HR for every 5 years 1.21, 95%CI 1.08-1.35, P < 0.001) and the presence of diabetes mellitus (HR 2.26, 95%CI 1.0-5.0, P = 0.04) being significant associated factors. CONCLUSION: There was a high frequency of AEs in patients with empyema, but most were considered preventable, especially the length of hospitalization, which could be reduced through timely surgery.

Sex-related differences in COPD in five Latin American cities: the PLATINO study.

There is evidence to suggest sex differences exists in chronic obstructive pulmonary disease (COPD) clinical expression. We investigated sex differences in health status perception, dyspnoea and physical activity, and factors that explain these differences using an epidemiological sample of subjects with and without COPD. PLATINO is a cross-sectional, population-based study. We defined COPD as post-bronchodilator forced expiratory volume in 1 s/forced vital capacity ratio <0.70, and evaluated health status perception (Short Form (SF)-12 questionnaire) and dyspnoea (Medical Research Council scale). Among 5,314 subjects, 759 (362 females) had COPD and 4,555 (2,850 females) did not. In general, females reported more dyspnoea and physical limitation than males. 54% of females without COPD reported a dyspnoea score ≥ 2 versus 35% of males. A similar trend was observed in females with COPD (63% versus 44%). In the entire study population, female sex was a factor explaining dyspnoea (OR 1.60, 95%CI 1.40-1.84) and SF-12 physical score (OR -1.13, 95%CI -1.56- -0.71). 40% of females versus 28% of males without COPD reported their general health status as fair-to-poor. Females with COPD showed a similar trend (41% versus 34%). Distribution of COPD severity was similar between sexes, but currently smoking females had more severe COPD than currently smoking males. There are important sex differences in the impact that COPD has on the perception of dyspnoea, health status and physical activity limitation.

Changes in the FEV1/FVC ratio during childhood and adolescence: an intercontinental study.

In children, the ratio of forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) is reportedly constant or falls linearly with age, whereas the ratio of residual volume (RV) to total lung capacity (TLC) remains constant. This seems counter-intuitive given the changes in airway properties, body proportions, thoracic shape and respiratory muscle function that occur during growth. The age dependence of lung volumes, FEV1/FVC and RV/TLC were studied in children worldwide. Spirometric data were available for 22,412 healthy youths (51.4% male) aged 4-20 yrs from 15 centres, and RV and TLC data for 2,253 youths (56.7% male) from four centres; three sets included sitting height (SH). Data were fitted as a function of age, height and SH. In childhood, FVC outgrows TLC and FEV1, leading to falls in FEV1/FVC and RV/TLC; these trends are reversed in adolescence. Taking into account SH materially reduces differences in pulmonary function within and between ethnic groups. The highest FEV1/FVC ratios occur in those shortest for their age. When interpreting lung function test results, the changing pattern in FEV1/FVC and RV/TLC should be considered. Prediction equations for children and adolescents should take into account sex, height, age, ethnic group, and, ideally, also SH.

Gripe A pandémica en una unidad de cuidados intensivos: experiencia en España y Latinoamérica (Grupo Español de Trabajo de Gripe A Grave/Sociedad Española de Medicina Intensiva, Crítica y Unidades Coronarias) / Pandemic Influenza A in the ICU: Experience in Spain and Latin America GETGAG/SEMICYUC/(Spanish Work Group on Severe Pandemic Influenza A/SEMICYUC)

Introducción: La pandemia de gripe A (H1N1)v es la primera pandemia en la que las unidades de cuidados intensivos (UCI) desempeñan un papel fundamental. Su evolución ha sido muy rápida desde los primeros casos diagnosticados en México y la afectación posterior de países del cono sur hasta su llegada a Europa durante la época estival. Objetivo: Comparar las características clínicas y de evolución de los pacientes críticos ingresados hasta el 31 de julio de 2009 en España con algunas series de Latinoamérica. Material y método: Se consideraron 6 series de pacientes ingresados en la UCI. Se realizaron comparaciones de las características clínicas, complicaciones y evolución entre las series. Resultados: Los datos evidencian una población joven (35-45 años) con predominio de ingresos por neumonía viral con grave insuficiencia respiratoria y una elevada necesidad de ventilación mecánica (60-100%). Si bien algunas determinadas poblaciones, como los obesos, las embarazadas y los pacientes con enfermedad pulmonar crónica, parecen estar expuestas a un riesgo más elevado, la ausencia de comorbilidades alcanza un porcentaje considerable en casi todas las series (40-50%). La mortalidad superior en Latinoamérica osciló entre el 25 y el 50%, y demostró el particular potencial patogénico del nuevo virus. El uso del tratamiento antiviral es tardío (entre 3 y 6 días) y poco generalizado, con mayor retraso en Latinoamérica respecto de España. Conclusiones: Estos datos indican que una estrategia de tratamiento más intensivo con un acceso más precoz y fácil al antiviral podría reducir el número de pacientes que requieren UCI y su mortalidad (AU)

Introduction: Pandemic Influenza A (H1N1)v infection is the first pandemic in which intensive care units (ICU) play a fundamental role. It has spread very rapidly since the first cases were diagnosed in Mexico with the subsequent spread of the virus throughout the Southern Cone and Europe during the summer season. Objective: This study has aimed to compare the clinical presentation and outcome among the critical patients admitted to the ICU until July 31, 2009 in Spain with some series from Latin America. Material and method: Six series of critically ill patients admitted to the ICU were considered. Clinical characteristics, complications and outcome were compared between series. Results: Young patients (35-45 years) with viral pneumonia as a predominant ICU admission cause with severe respiratory failure and a high need of mechanical ventilation (60-100%) were affected. Obesity, pregnancy and chronic lung disease were risk factors associated with a worse outcome, however there was a high number of patients without comorbidities (40-50%). Mortality rate was between 25-50% and higher in the Latin America series, demonstrating the specific potential pathogenesis of the new virus. The use of antiviral treatment was delayed (between 3 and 6 days) and not generalized, with greater delay in Latin America in regards to Spain. Conclusions: These data suggest that a more aggressive treatment strategy, with earlier and easier access to the antiviral treatment might reduce the number of ICU admissions and mortality (AU)

[Pandemic influenza A in the ICU: experience in Spain and Latin America. GETGAG/SEMICYUC/(Spanish Working Group on Severe Pandemic Influenza A/SEMICYUC)]. / Gripe A pandémica en una unidad de cuidados intensivos: experiencia en España y Latinoamérica (Grupo Español de Trabajo de Gripe A Grave/Sociedad Española de Medicina Intensiva, Crítica y Unidades Coronarias).

INTRODUCTION: Pandemic Influenza A (H1N1)v infection is the first pandemic in which intensive care units (ICU) play a fundamental role. It has spread very rapidly since the first cases were diagnosed in Mexico with the subsequent spread of the virus throughout the Southern Cone and Europe during the summer season. OBJECTIVE: This study has aimed to compare the clinical presentation and outcome among the critical patients admitted to the ICU until July 31, 2009 in Spain with some series from Latin America. MATERIAL AND METHOD: Six series of critically ill patients admitted to the ICU were considered. Clinical characteristics, complications and outcome were compared between series. RESULTS: Young patients (35-45 years) with viral pneumonia as a predominant ICU admission cause with severe respiratory failure and a high need of mechanical ventilation (60-100%) were affected. Obesity, pregnancy and chronic lung disease were risk factors associated with a worse outcome, however there was a high number of patients without comorbidities (40-50%). Mortality rate was between 25-50% and higher in the Latin America series, demonstrating the specific potential pathogenesis of the new virus. The use of antiviral treatment was delayed (between 3 and 6 days) and not generalized, with greater delay in Latin America in regards to Spain. CONCLUSIONS: These data suggest that a more aggressive treatment strategy, with earlier and easier access to the antiviral treatment might reduce the number of ICU admissions and mortality.

Can a normal peak expiratory flow exclude severe chronic obstructive pulmonary disease?

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is underdiagnosed. One barrier to diagnosis is the limited availability of spirometry testing, but in adults at risk for COPD, a normal pre-bronchodilator (pre-BD) peak expiratory flow (PEF) may rule out clinically significant COPD. OBJECTIVE: To identify post-BD airway obstruction using data from 13 708 individuals aged >or=40 years from the PLATINO and BOLD studies. METHODS: We evaluated different cut-off points of pre-BD. The PEF was obtained from a diagnostic-quality spirometer (not a mechanical PEF meter). At least one of the following COPD risk factors was present in 77% of the subjects: chronic respiratory symptoms; exposure to tobacco smoke, biomass smoke or dust in the workplace; or a previous diagnosis of asthma, COPD, emphysema or chronic bronchitis. RESULTS: Although the positive predictive value was low as expected, a pre-BD PEF of >or=70% predicted effectively ruled out Stages III and IV COPD of the Global Initiative for Chronic Obstructive Lung Disease. Among those with at least one risk factor, only 12% would require confirmatory spirometry using this criterion. CONCLUSIONS: Adding PEF measurement to a screening questionnaire may rule out severe to very severe COPD without the need for pre- and post-BD spirometry testing. Confirmation is needed from a study using inexpensive PEF meters or pocket spirometers with a staged screening protocol.

Preoperative continuous positive airway pressure compliance in children with obstructive sleep apnea syndrome: assessed by a simplified approach.

INTRODUCTION: The frequency of diagnoses of obstructive sleep apnea syndrome (OSAS) in children is increasing and more and more adenotonsillectomies (A&T) are being performed on severely ill children who have a higher perioperatory risk. The objective of the present study was to describe preoperative compliance in the use of continuous positive airway pressure (CPAP) in children with OSAS, when this treatment was prescribed as a means of preventing complications. PATIENTS AND METHODS: We describe data from children with severe OSAS caused by hypertrophy of the adenoids and tonsils, but with no craniofacial abnormalities. CPAP pressure was adjusted either during diurnal polysomnography with sleep deprivation or by self-adjusting devices. Follow-up was conducted through weekly interviews and the downloading of data recorded by the equipment. RESULTS: 48 children were included; 73% of them used a CPAP machine > or =3h per night, and 31% used it for > or =6h per night. The variables associated with good equipment compliance included higher BMI, higher pressure levels in the devices, and a higher number of episodes of apneas and hypopneas. Children who weighed > or =30kg used CPAP for > or =3h per night more often (OR 16, 95% CI 1.9-137). Compliance levels with fixed and self-adjusting CPAP were similar, and side effects in both cases were slight and limited to those caused by the pressure of the masks on patients' skin. One case of excessive bleeding was the only complication reported during A&T. CONCLUSIONS: The mean preoperative use of CPAP equipment by children with severe OSAS was 4.5+/-2.6h. Seventy-three percent of subjects used the equipment for >/=3h.