Introdução: O teste de apneia respiratória tem sido testado e demonstrou ser de utilidade clínica. Objetivos: Determinar o tempo de apneia voluntária máxima em pacientes com distúrbios ventilatórios obstrutivos (DVO) e em indivíduos normais e correlacionar os tempos de apneia com os testes de função pulmonar. Métodos: Foi realizado um estudo caso-controle incluindo pacientes com DVO (casos) e um grupo controle, composto por voluntários com espirometria normal, recrutados no Hospital de Clínicas de Porto Alegre (HCPA). A espirometria foi realizada com espirômetro computadorizado e o teste de apneia respiratória utilizando-se um sistema eletrônico microprocessado e um pneumotacógrafo ((Hans Rudolph ® – Kansas OH, EUA)– Kansas OH, EUA) como transdutor de fluxo. As curvas de fluxo respiratório foram exibidas em tempo real em um computador portátil e os tempos máximos de apneia voluntária inspiratória e expiratória (TAVIM e TAVEM) foram determinados a partir do sinal adquirido. Resultados: Um total de 35 pacientes com DVO (casos) e 16 controles foram incluídos no estudo. O TAVIM foi significativamente menor nos casos (22,3 ± 11,8 s) do que no grupo controle (31,5 ± 15,7 s) com p = 0,025. O TAVEM também foi significativamente menor nos casos (16,9 ± 6,6 s) do que no grupo controle (22,1 ± 7,9 s) com p = 0,017. Foram encontradas correlações positivas moderadas entre TAVIM e CVF (r = 0,476, p = 0,004) e entre TAVIM e VEF1 (r = 0,383, p = 0,023). Conclusões: As medidas de TAVIM e TAVEM foram significativamente menores nos casos do que nos controles, e o TAVIM teve correlação moderada com a CVF e VEF1. Estes resultados fornecem uma evidência adicional da utilidade clínica do tempo de apneia como teste de função pulmonar. / Introduction: Breath-holding test has been tested in some clinical scenarios and has proved to be of clinical utility. Objectives: To determine the maximum voluntary breath-holding time in patients with obstructive ventilator defects and in normal subjects and to correlate the breathholding times with pulmonary function tests. Methods: We conducted a case-control study including patients with obstructive ventilator defects and a control group consisted of volunteers recruited in the same hospital, with normal spirometry. Spirometry was performed using a computerized spirometer. The Breath-holding test was conducted using an electronic microprocessor and a (Hans Rudolph ® – Kansas OH, EUA)pneumotachograph and flow transducer. Respiratory flow curves were displayed in real time on a portable computer. The maximal voluntary apnea inspiratory and expiratory times (MVAIT and MVAET) were determined from the acquired signal. Results: A total of 35 patients with obstructive ventilatory defects and 16 controls met the inclusion criteria and were included in the analysis. The MVAIT was lower in cases (22.3 ± 11.8 seconds) than in controls (31.5 ± 15.7 seconds) (p=0.025). MVAET was also lower in cases than in controls (16.9 ± 6.6 vs. 22.1 ± 7.9; p=0.017). We found positive and significant correlations between MVAIT and FVC (L) (r=0.476; p=0.004) and between MVAIT and FEV1 (L) (r=0.383; p=0.023). Conclusions: MVAIT and MVAET were significant lower in patients with obstructive ventilatory defects than in controls, and that MVAIT was correlated positively with FVC and FEV1 in cases. Our results provide additional evidence of usefulness of MVAIT as a pulmonary function test.

Introdução: O teste de apneia respiratória tem sido testado e demonstrou ser de utilidade clínica. Objetivos: Determinar o tempo de apneia voluntária máxima em pacientes com distúrbios ventilatórios obstrutivos (DVO) e em indivíduos normais e correlacionar os tempos de apneia com os testes de função pulmonar. Métodos: Foi realizado um estudo caso-controle incluindo pacientes com DVO (casos) e um grupo controle, composto por voluntários com espirometria normal, recrutados no Hospital de Clínicas de Porto Alegre (HCPA). A espirometria foi realizada com espirômetro computadorizado e o teste de apneia respiratória utilizando-se um sistema eletrônico microprocessado e um pneumotacógrafo ((Hans Rudolph ® – Kansas OH, EUA)– Kansas OH, EUA) como transdutor de fluxo. As curvas de fluxo respiratório foram exibidas em tempo real em um computador portátil e os tempos máximos de apneia voluntária inspiratória e expiratória (TAVIM e TAVEM) foram determinados a partir do sinal adquirido. Resultados: Um total de 35 pacientes com DVO (casos) e 16 controles foram incluídos no estudo. O TAVIM foi significativamente menor nos casos (22,3 ± 11,8 s) do que no grupo controle (31,5 ± 15,7 s) com p = 0,025. O TAVEM também foi significativamente menor nos casos (16,9 ± 6,6 s) do que no grupo controle (22,1 ± 7,9 s) com p = 0,017. Foram encontradas correlações positivas moderadas entre TAVIM e CVF (r = 0,476, p = 0,004) e entre TAVIM e VEF1 (r = 0,383, p = 0,023). Conclusões: As medidas de TAVIM e TAVEM foram significativamente menores nos casos do que nos controles, e o TAVIM teve correlação moderada com a CVF e VEF1. Estes resultados fornecem uma evidência adicional da utilidade clínica do tempo de apneia como teste de função pulmonar. / Introduction: Breath-holding test has been tested in some clinical scenarios and has proved to be of clinical utility. Objectives: To determine the maximum voluntary breath-holding time in patients with obstructive ventilator defects and in normal subjects and to correlate the breathholding times with pulmonary function tests. Methods: We conducted a case-control study including patients with obstructive ventilator defects and a control group consisted of volunteers recruited in the same hospital, with normal spirometry. Spirometry was performed using a computerized spirometer. The Breath-holding test was conducted using an electronic microprocessor and a (Hans Rudolph ® – Kansas OH, EUA)pneumotachograph and flow transducer. Respiratory flow curves were displayed in real time on a portable computer. The maximal voluntary apnea inspiratory and expiratory times (MVAIT and MVAET) were determined from the acquired signal. Results: A total of 35 patients with obstructive ventilatory defects and 16 controls met the inclusion criteria and were included in the analysis. The MVAIT was lower in cases (22.3 ± 11.8 seconds) than in controls (31.5 ± 15.7 seconds) (p=0.025). MVAET was also lower in cases than in controls (16.9 ± 6.6 vs. 22.1 ± 7.9; p=0.017). We found positive and significant correlations between MVAIT and FVC (L) (r=0.476; p=0.004) and between MVAIT and FEV1 (L) (r=0.383; p=0.023). Conclusions: MVAIT and MVAET were significant lower in patients with obstructive ventilatory defects than in controls, and that MVAIT was correlated positively with FVC and FEV1 in cases. Our results provide additional evidence of usefulness of MVAIT as a pulmonary function test.

Introdução: O teste de apneia respiratória tem sido testado e demonstrou ser de utilidade clínica. Objetivos: Determinar o tempo de apneia voluntária máxima em pacientes com distúrbios ventilatórios obstrutivos (DVO) e em indivíduos normais e correlacionar os tempos de apneia com os testes de função pulmonar. Métodos: Foi realizado um estudo caso-controle incluindo pacientes com DVO (casos) e um grupo controle, composto por voluntários com espirometria normal, recrutados no Hospital de Clínicas de Porto Alegre (HCPA). A espirometria foi realizada com espirômetro computadorizado e o teste de apneia respiratória utilizando-se um sistema eletrônico microprocessado e um pneumotacógrafo ((Hans Rudolph ® – Kansas OH, EUA)– Kansas OH, EUA) como transdutor de fluxo. As curvas de fluxo respiratório foram exibidas em tempo real em um computador portátil e os tempos máximos de apneia voluntária inspiratória e expiratória (TAVIM e TAVEM) foram determinados a partir do sinal adquirido. Resultados: Um total de 35 pacientes com DVO (casos) e 16 controles foram incluídos no estudo. O TAVIM foi significativamente menor nos casos (22,3 ± 11,8 s) do que no grupo controle (31,5 ± 15,7 s) com p = 0,025. O TAVEM também foi significativamente menor nos casos (16,9 ± 6,6 s) do que no grupo controle (22,1 ± 7,9 s) com p = 0,017. Foram encontradas correlações positivas moderadas entre TAVIM e CVF (r = 0,476, p = 0,004) e entre TAVIM e VEF1 (r = 0,383, p = 0,023). Conclusões: As medidas de TAVIM e TAVEM foram significativamente menores nos casos do que nos controles, e o TAVIM teve correlação moderada com a CVF e VEF1. Estes resultados fornecem uma evidência adicional da utilidade clínica do tempo de apneia como teste de função pulmonar. / Introduction: Breath-holding test has been tested in some clinical scenarios and has proved to be of clinical utility. Objectives: To determine the maximum voluntary breath-holding time in patients with obstructive ventilator defects and in normal subjects and to correlate the breathholding times with pulmonary function tests. Methods: We conducted a case-control study including patients with obstructive ventilator defects and a control group consisted of volunteers recruited in the same hospital, with normal spirometry. Spirometry was performed using a computerized spirometer. The Breath-holding test was conducted using an electronic microprocessor and a (Hans Rudolph ® – Kansas OH, EUA)pneumotachograph and flow transducer. Respiratory flow curves were displayed in real time on a portable computer. The maximal voluntary apnea inspiratory and expiratory times (MVAIT and MVAET) were determined from the acquired signal. Results: A total of 35 patients with obstructive ventilatory defects and 16 controls met the inclusion criteria and were included in the analysis. The MVAIT was lower in cases (22.3 ± 11.8 seconds) than in controls (31.5 ± 15.7 seconds) (p=0.025). MVAET was also lower in cases than in controls (16.9 ± 6.6 vs. 22.1 ± 7.9; p=0.017). We found positive and significant correlations between MVAIT and FVC (L) (r=0.476; p=0.004) and between MVAIT and FEV1 (L) (r=0.383; p=0.023). Conclusions: MVAIT and MVAET were significant lower in patients with obstructive ventilatory defects than in controls, and that MVAIT was correlated positively with FVC and FEV1 in cases. Our results provide additional evidence of usefulness of MVAIT as a pulmonary function test.

Orientador: Alberto Cliquet Junior / Tese (doutorado) - Universidade Estadual de Campinas. Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-15T13:59:53Z (GMT). No. of bitstreams: 1 Pithon_KarlaRocha_D.pdf: 2904510 bytes, checksum: 5e11e0764c499e8dce17f09bd0f6d191 (MD5) Previous issue date: 2010 / Resumo: Pacientes com lesão medular reconhecidamente desenvolvem muitas adaptações sistêmicas. Condições, como fraqueza da musculatura respiratória, paralisia e alterações na função pulmonar e conseqüentemente o aumento do índice de doenças pulmonares, são observadas. Recentemente, o aumento de doenças cardiovasculares também tem ocorrido entre esses pacientes, além das complicações provenientes da osteoporose que já são bem conhecidas. O objetivo deste trabalho foi avaliar as alterações do sistema cardiorrespiratório e esquelético de pacientes com lesão medular em 4 estudos. O estudo 1 avaliou a variabilidade da frequência cardíaca na posição supina e sentada e arritmia sinusal respiratória (ASR) de 37 homens com e sem lesão medular. Os pacientes tetraplégicos apresentaram uma redução dos valores máximos da frequência cardíaca durante ASR. O estudo 2 avaliou a função pulmonar de 23 pacientes com tetraplegia. Os valores de capacidade vital forçada, volume expiratório forçado 1s e ventilação voluntária máxima mostraram que a capacidade pulmonar dos pacientes com lesão medular foi reduzida. O estudo 3 propôs a adaptação do teste de caminhada de 6 minutos para 9 pacientes com paraplegia completa auxiliados por marcha artificial com eletroestimulação neuromuscular e andador. O estudo 4 investigou a densidade mineral óssea e fatores de risco cardiovascular de 44 homens com e sem lesão medular. Os pacientes com lesão medular apresentaram osteoporose e/ou osteopenia e o espessamento da camada íntima-média da carótida, porém os valores do lipidograma e triglicérides foram dentro da faixa de normalidade. A pressão arterial foi menor nos pacientes tetraplégicos. Análise estatística: Os dados foram apresentados em mediana (intervalo interquartil) e/ou média (±DP) e em Box-plot. Diferenças entre grupos foram demonstradas pelo intervalo de confiança da mediana, nível de significância em 5% ou teste t pareado. Conclusões: A atuação simpática e parassimpática no coração alcançou a homeostase, quando os pacientes foram mantidos nas posições supina ou sentada e o teste de ASR mostrou uma diminuição da atuação parassimpática no coração dos pacientes tetraplégicos, possivelmente para compensar uma diminuição ou ausência da atuação simpática, devido ao comprometimento do sistema autonômico pela lesão medular. O teste de caminhada de 6 minutos foi adaptado para avaliar os pacientes com lesão medular completa e se mostrou eficiente. Já a avaliação da função pulmonar dos pacientes mostrou a necessidade de novas equações de predição baseadas em uma população específica e suas características. Por último, os resultados obtidos através da densitometria mineral óssea comprovaram a presença de osteoporose e/ou osteopenia nos pacientes com lesão medular. E um aumento na espessura da camada intima-média da carótida foi observado através da ultrassonografia de carótida. Esses dados reforçam a hipótese de uma possível associação entre essas duas patologias. / Abstract: It is known that individuals with Spinal Cord Injury (SCI) present systemic adaptation. SCI causes respiratory muscle weakness, paralysis and abnormal pulmonary function. Cardiovascular disease is also increased in spinal cord injured subjects and osteoporosis as well. The aim of this study was to assess cardio respiratory and bone diseases in subjects with SCI. Four studies were performed. The first study assessed heart rate variability in supine and seated position and respiratory sinus arrhythmia (RSA) maneuver in 37 subjects with and without SCI. Tetraplegic subjects showed the lowest values of maximal heart rate during RSA. The second study assessed pulmonary function in 23 tetraplegic subjects. Forced vital capacity, maximal voluntary ventilation, forced expired volume showed that the SCI subjects' pulmonary capacity was reduced when compared with able body subjects. The third study adapted the "6 minutes' walk test" to assess complete patients with SCI during gait therapy. The fourth study investigated the clinical presence of osteoporosis and cardiovascular risk factors in 44 subjects with and without SCI. Subjects showed osteoporosis or osteopenia and increased intima-media thickness, although lipids and triglycerides were with normal ranges. Blood pressure in tetraplegic subjects was lower than in paraplegic and control groups. Statistical Analysis: Data are expressed as median (interquartile interval) and presented in box-plot (median, 1st and 3rd quartiles, minimum and maximum). Differences between groups were demonstrated by confidence interval of median, significance level set at ? = 0.05, or mean (±SD) and paired t test. Conclusions: Sympathetic and parasympathetic nervous system allow homeostasis when the subjects are kept in supine or seated position; RSA maneuver showed a reduction in parasympathetic system action in the heart of tetraplegic subjects to compensate a reduction or loss of sympathetic action in spinal cord lesion. "Six minutes walk test" was well adapted and efficient. Pulmonary function showed the necessity to create new predicts equations based on local population characteristics. Finally, bone mineral density showed osteoporosis or osteopenia in paraplegic and tetraplegic individuals as well as increased carotid intima-media thickness measured through ultrasound exam. / Doutorado / Pesquisa Experimental / Doutor em Cirurgia

Spirometry is the most important tool in diagnosing pulmonary disease and is the most frequently performed pulmonary function test. Respiratory disease is also one of the greatest causes for morbidity and mortality on the Hopi Nation, but no specific reference equations exist for this unique population. The purpose of this study was to determine if population reference equations were necessary for these children and, if needed, to create new age and race-specific pulmonary nomograms for Hopi children. Two hundred and ninety-two healthy children, ages 4-13 years, attending Hopi Nation elementary schools in Arizona, were asked to perform spirometry for a full battery of pulmonary volumes and capacities of which the following were analyzed: forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), FEV1 % (FEV1/FVC), FEF25-75% and peak expiratory flow rate (PEFR). Spirometric data from Navajo children living in the same geographical region as the Hopi children were compared as well as spirometric data from common reference values used for other ethnic groups in the USA. Spirometry tests from 165 girls and 127 boys met American Thoracic Society quality control standards. We found that the natural log of height, body mass and age were significant predictors of FEV1, FVC, and FEF25-75% in the gender-specific models and that lung function values all increased with height and age as expected. The predictions using the equations derived for Navajo, Caucasian, Mexican-American, African-American youth were significantly different (P ≤ 0.05) from the predictions derived from the Hopi equations for all of the variables across both genders, with the exceptions of Hopi versus Navajo FEV1/FVC in the males and Hopi versus Caucasians FEF25-75% in the females. Thus it would appear for this population important to have specific formulae to provide more accurate reference values.

Spirometry is the most important tool in diagnosing pulmonary disease and is the most frequently performed pulmonary function test. Since respiratory disease is the single greatest cause for morbidity and mortality on the Navajo Nation, the purpose of this study was to create newage and race-specific pulmonary nomograms for Navajo children. Five hundred fifty-eight healthy children, ages 6-14 years, attending Navajo Nation elementary schools in Arizona, were asked to perform spirometry to develop population-specific and tribe-specific nomograms for forced vitalcapacity (FVC), forced expiratory volume in 1 sec (FEV1), and FEV1 Ratio (FEV1/FVC). Spirometry tests from 284 girls and 274 boys met American Thoracic Society quality control standards. Lung function values, except for FEV1/FVC, all increased with height. The lower limit of the normal range for FEV1/FVC was 80%. The spirometry reference equations from the healthyboys and girls were developed. Height and the natural log of height were significant predictors of FEV1, FVC, and FEF25-75% in the gender-specific models. The resulting population-specific spirometry reference equations should be used when testing Navajo children ages 6-14 years. However, the use of the NHANES III spirometry reference equations for Caucasian children may not result in significant misclassification in clinical settings providing that a maximal effort is given by the Navajo child being tested.

Title: Verification of the effect of Ventolin Inhaler N in athletes without a diagnosis of asthma. Thesis' objective: The main objective of this Thesis is to determine whether the medicament Ventolin Inhaler N affects the performance of athletes without a diagnosis of asthma. Specifically, it is about how this medicament influences the parameters in aerobic and anaerobic zone, spirometric parameters and total performance. The other objective is to verify if any of the adverse events of Ventolin Inhaler N appears before the load. Methods: The descriptive analysis method for obtaining information about the issue is used in this Thesis. A test up to a vita maxima on a treadmill according to the protocol of Bunce, spirometric measurement and an answer sheet for the evaluation of subjective feelings immediately after the test is used for the research. Test was realized using a method repeated measurement, each tested person passed the test twice, once using the Ventolin Inhaler N and once without it. Results were recorded into tables and analyzed in SPSS programme using statistical methods. Results: The medicament Ventolin Inhaler N affects the performance of athletes without a diagnosis of asthma. The Ventolin influences the spirometric parameters measured before the test (FEV1, FVC), the spirometric...

Introdução: O uso de biomassa como combustível para aquecimento e preparação de alimentos vem sendo considerado como um importante fator associado à prevalência aumentada de sintomas respiratórios e à perda de função pulmonar. No presente estudo apresentamos os efeitos respiratórios da exposição crônica à combustão de biomassa (BM) dentro (BMD) ou fora (BMF) do domicílio em uma população do interior do Brasil e comparamos os resultados aos de indivíduos da mesma população que utilizam gás liquefeito de petróleo (GLP). Métodos: Foram incluídos 1402 indivíduos em 260 domicílios divididos em três grupos de acordo com a exposição (GLP, BMD, BMF). Os sintomas respiratórios foram avaliados utilizando questionários validados. O índice de refletância de filtros de papel foi utilizado para avaliar a exposição à biomassa. Em 48 domicílios a concentração de material particulado PM2,5 também foi quantificada. Provas de função pulmonar (PFP) foram realizadas em 120 indivíduos. Resultados: O índice de refletância correlacionou-se diretamente com a concentração de PM2,5 (r=0,92, p<0,001) e foi portanto utilizado para estimar a exposição (ePM2,5). Demonstramos aumento significativo do ePM2,5 no grupo BMD e BMF em comparação com o grupo GLP (p<0,001). Houve ainda aumento significativo da razão de chances (OR) para tosse produtiva, chiado e dispnéia nos adultos expostos à BMD (OR=2,93, 2,33, 2,59, respectivamente) e BMF (OR=1,78, 1,78, 1,80, respectivamente) em comparação com o grupo GLP. As PFP demonstraram que tanto o grupo BM-nãotabagista como GLP-tabagista apresentaram redução no % do VEF1 predito e na relação VEF1/CVF quando comparado com GLP-não-tabagista (p=0,002), o mesmo ocorrendo para o grupo BM-tabagista, em relação a todos os demais (p<0,05). A prevalência de obstrução de vias aéreas encontrada no grupo BM-não-tabagista e GLP-tabagista foi semelhante (20%) e menor do que a observada no grupo BM-tabagista (33%). A PFP correlacionou-se inversamente com o tempo de exposição e a concentração de ePM2,5 (p<0,001). Conclusões: A exposição crônica à combustão de biomassa está associada com o aumento da prevalência de sintomas respiratórios, redução da função pulmonar e desenvolvimento de doença pulmonar obstrutiva crônica. Esses efeitos estão associados com a duração e magnitude da exposição e são potencializadas pelo tabagismo. / Introduction: The use of biomass fuels for cooking and heating is considered an important factor associated with respiratory symptoms and loss of pulmonary function. We report the respiratory effects of chronic exposure to biomass (BM) combustion in a Brazilian population and compared the results with those of individuals from the same community using Liquefied Petroleum Gas (LPG). Methods: 1,402 individuals in 260 residences were divided into three groups according to exposure (LPG, indoor-BM, outside-BM). Respiratory symptoms were assessed using questionnaires. Reflectance of paper filters was used to assess BM. In 48 residences the amount of PM2.5 was also quantified. Pulmonary function tests (PFT) were performed in 120 individuals. Results: Reflectance-index correlated directly with PM2.5 (r=0.92, p<0.001) and was used to estimate exposure (ePM2.5). There was a significant increase in ePM2.5 in Indoor-BM and Outside-BM, compared to LPG (p<0.001). There was a significantly increased odds ratio (OR) for cough with sputum, sneezing and dyspnea in adults exposed to Indoor-BM (OR=2.93, 2.33, 2.59, respectively) and Outside-BM (OR=1.78, 1.78, 1.80, respectively) compared to LPG. PFTs revealed both non-smoker-BM and smoker-LPG individuals to have decreased %predicted-FEV1 and FEV1/FVC as compared to non-smoker-LPG (p=0.022). Reduction was also observed in both parameters between smoker-BM and other groups (p<0.05). The prevalence of chronic obstructive pulmonary disease was 20% for both non-smoker-BM and smoker-LPG and smaller than that observed for smoker-BM (33%). PFT data was inversely correlated with duration and ePM2.5 (p<0.001). The prevalence of airway obstruction was 20% in both non-smoker-BM and smoker-LPG subjects. Conclusions: Chronic exposure to BM is associated with increased prevalence of respiratory symptoms, reduced lung function and development of chronic obstructive pulmonary disease. These effects are associated with the duration and magnitude of exposure and are exacerbated by tobacco smoke.

Introdução: O uso de biomassa como combustível para aquecimento e preparação de alimentos vem sendo considerado como um importante fator associado à prevalência aumentada de sintomas respiratórios e à perda de função pulmonar. No presente estudo apresentamos os efeitos respiratórios da exposição crônica à combustão de biomassa (BM) dentro (BMD) ou fora (BMF) do domicílio em uma população do interior do Brasil e comparamos os resultados aos de indivíduos da mesma população que utilizam gás liquefeito de petróleo (GLP). Métodos: Foram incluídos 1402 indivíduos em 260 domicílios divididos em três grupos de acordo com a exposição (GLP, BMD, BMF). Os sintomas respiratórios foram avaliados utilizando questionários validados. O índice de refletância de filtros de papel foi utilizado para avaliar a exposição à biomassa. Em 48 domicílios a concentração de material particulado PM2,5 também foi quantificada. Provas de função pulmonar (PFP) foram realizadas em 120 indivíduos. Resultados: O índice de refletância correlacionou-se diretamente com a concentração de PM2,5 (r=0,92, p<0,001) e foi portanto utilizado para estimar a exposição (ePM2,5). Demonstramos aumento significativo do ePM2,5 no grupo BMD e BMF em comparação com o grupo GLP (p<0,001). Houve ainda aumento significativo da razão de chances (OR) para tosse produtiva, chiado e dispnéia nos adultos expostos à BMD (OR=2,93, 2,33, 2,59, respectivamente) e BMF (OR=1,78, 1,78, 1,80, respectivamente) em comparação com o grupo GLP. As PFP demonstraram que tanto o grupo BM-nãotabagista como GLP-tabagista apresentaram redução no % do VEF1 predito e na relação VEF1/CVF quando comparado com GLP-não-tabagista (p=0,002), o mesmo ocorrendo para o grupo BM-tabagista, em relação a todos os demais (p<0,05). A prevalência de obstrução de vias aéreas encontrada no grupo BM-não-tabagista e GLP-tabagista foi semelhante (20%) e menor do que a observada no grupo BM-tabagista (33%). A PFP correlacionou-se inversamente com o tempo de exposição e a concentração de ePM2,5 (p<0,001). Conclusões: A exposição crônica à combustão de biomassa está associada com o aumento da prevalência de sintomas respiratórios, redução da função pulmonar e desenvolvimento de doença pulmonar obstrutiva crônica. Esses efeitos estão associados com a duração e magnitude da exposição e são potencializadas pelo tabagismo. / Introduction: The use of biomass fuels for cooking and heating is considered an important factor associated with respiratory symptoms and loss of pulmonary function. We report the respiratory effects of chronic exposure to biomass (BM) combustion in a Brazilian population and compared the results with those of individuals from the same community using Liquefied Petroleum Gas (LPG). Methods: 1,402 individuals in 260 residences were divided into three groups according to exposure (LPG, indoor-BM, outside-BM). Respiratory symptoms were assessed using questionnaires. Reflectance of paper filters was used to assess BM. In 48 residences the amount of PM2.5 was also quantified. Pulmonary function tests (PFT) were performed in 120 individuals. Results: Reflectance-index correlated directly with PM2.5 (r=0.92, p<0.001) and was used to estimate exposure (ePM2.5). There was a significant increase in ePM2.5 in Indoor-BM and Outside-BM, compared to LPG (p<0.001). There was a significantly increased odds ratio (OR) for cough with sputum, sneezing and dyspnea in adults exposed to Indoor-BM (OR=2.93, 2.33, 2.59, respectively) and Outside-BM (OR=1.78, 1.78, 1.80, respectively) compared to LPG. PFTs revealed both non-smoker-BM and smoker-LPG individuals to have decreased %predicted-FEV1 and FEV1/FVC as compared to non-smoker-LPG (p=0.022). Reduction was also observed in both parameters between smoker-BM and other groups (p<0.05). The prevalence of chronic obstructive pulmonary disease was 20% for both non-smoker-BM and smoker-LPG and smaller than that observed for smoker-BM (33%). PFT data was inversely correlated with duration and ePM2.5 (p<0.001). The prevalence of airway obstruction was 20% in both non-smoker-BM and smoker-LPG subjects. Conclusions: Chronic exposure to BM is associated with increased prevalence of respiratory symptoms, reduced lung function and development of chronic obstructive pulmonary disease. These effects are associated with the duration and magnitude of exposure and are exacerbated by tobacco smoke.

The overall aim of the research described in this thesis was to evaluate the effect of vitamin A supplementation on respiratory health, assessed by lung function in children aged 6--9 years. It comprises three studies. / The first study determined the magnitude of vitamin A deficiency in the target population in Wukro wereda, Northern Ethiopia. Of the 1339 eligible children identified by house to house surveys, 824 had complete data for vitamin A indicators and anthropometry. Xerophthalmia was detected in 5.8% of the children, 8.4% had serum retinol levels <0.35 mumol/L and 51.1% between 0.35--0.70 mumol/L. Liver vitamin A reserve was also found to be low in 41.0% of the children using the Modified Relative Dose Response (MRDR) and in about 85% of the children, the daily vitamin A intake was below the FAO/WHO basal requirement (<250 RE/day). / The second study found that in comparison with children with adequate vitamin A reserve (MRDR < 0.06), those with low reserve (MRDR &ge; 0.06) had forced expiratory volume in one second (FEV1) 48.8 ml (p = 0.006) lower when unadjusted, 23.1 ml (p = 0.04) when partially adjusted for age, gender and height and 14.1 ml (p = 0.20) when fully adjusted for demographic, general health, lung function and household related characteristics. / The third study describes the results of a randomized controlled trial (RCT) to evaluate the impact of vitamin A supplementation on respiratory health as assessed by change in FEV1 at 4 months. The average change was 53.3 ml (n = 496) and 53.8 ml (n = 501) in the vitamin A and placebo groups respectively. After adjusting for baseline covariates, the difference between them was -3.6 ml (95%CI: -21.6, 14.4). In sub-analysis of the data, gender and vitamin A status subcategories were found to be effect modifiers. / In conclusion, high dose vitamin A supplementation did not show an effect on change in FEV1 at 4 months in children aged 6--9 years with high prevalence of vitamin A deficiency. Sub-analysis findings suggest that the benefits to vitamin A intervention in the study setting can probably be achieved if the other nutritional deficiencies such as zinc are addressed. Moreover, the results also suggest that the effects of vitamin A supplementation on respiratory health status are complex and these need to be taken into account in future studies to assess the clinical and public health implications of vitamin A supplementation in this age group.