RESUMEN
Patients with chronic obstructive pulmonary disease (COPD) usually complain of symptoms such as cough, sputum, wheezing, and dyspnea. Little is known about clinical symptoms in individuals with restrictive ventilatory impairment. The aim of this study was to compare the prevalence and type of respiratory symptoms in patients with COPD to those reported by individuals with restrictive ventilatory impairment in the Proyecto Latinoamericano de Investigacion en Obstruccion Pulmonar study. Between 2002 and 2004, individuals ≥40 years of age from five cities in Latin America performed pre and post-bronchodilator spirometry and had their respiratory symptoms recorded in a standardized questionnaire. Among the 5315 individuals evaluated, 260 (5.1%) had a restrictive spirometric diagnosis (forced vital capacity (FVC) < lower limit of normal (LLN) with forced expiratory volume in the first second to forced vital capacity ratio (FEV1/FVC) ≥ LLN; American Thoracic Society (ATS)/European Respiratory Society (ERS) 2005) and 610 (11.9%) were diagnosed with an obstructive pattern (FEV1/FVC < LLN; ATS/ERS 2005). Patients with mild restriction wheezed more ((30.8%) vs. (17.8%); p < 0.028). No difference was seen in dyspnea, cough, and sputum between the two groups after adjusting for severity stage. The health status scores for the short form 12 questionnaire were similar in restricted and obstructed patients for both physical (48.4 ± 9.4 vs. 48.3 ± 9.8) and mental (50.8 ± 10.6 vs. 50.0 ± 11.5) domains. Overall, respiratory symptoms are not frequently reported by patients with restricted and obstructed patterns as defined by spirometry. Wheezing was more frequent in patients with restricted pattern compared with those with obstructive ventilatory defect. However, the prevalence of cough, sputum production, and dyspnea are not different between the two groups when adjusted by the same severity stage.
Asunto(s)
Tos/epidemiología , Disnea/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Esputo/metabolismo , Adulto , Anciano , Tos/etiología , Disnea/etiología , Femenino , Volumen Espiratorio Forzado , Estado de Salud , Humanos , América Latina/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Ruidos Respiratorios/etiología , Espirometría , Encuestas y Cuestionarios , Capacidad VitalRESUMEN
Little information exists regarding the epidemiology of the chronic bronchitis phenotype in unselected chronic obstructive pulmonary disease (COPD) populations. We examined the prevalence of the chronic bronchitis phenotype in COPD and non-COPD subjects from the PLATINO study, and investigated how it is associated with important outcomes. Post-bronchodilator forced expiratory volume in 1 s/forced vital capacity <0.70 was used to define COPD. Chronic bronchitis was defined as phlegm on most days, at least 3 months per year for ≥ 2 yrs. We also analysed another definition: cough and phlegm on most days, at least 3 months per year for ≥ 2 yrs. Spirometry was performed in 5,314 subjects (759 with and 4,554 without COPD). The proportion of subjects with and without COPD with chronic bronchitis defined as phlegm on most days, at least 3 months per year for ≥ 2 yrs was 14.4 and 6.2%, respectively. Using the other definition the prevalence was lower: 7.4% with and 2.5% without COPD. Among subjects with COPD, those with chronic bronchitis had worse lung function and general health status, and had more respiratory symptoms, physical activity limitation and exacerbations. Our study helps to understand the prevalence of the chronic bronchitis phenotype in an unselected COPD population at a particular time-point and suggests that chronic bronchitis in COPD is possibly associated with worse outcomes.
Asunto(s)
Bronquitis Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Bronquitis Crónica/complicaciones , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , México/epidemiología , Fenotipo , Prevalencia , América del Sur/epidemiología , EspirometríaRESUMEN
BACKGROUND: Acute bronchodilator responsiveness is an area of discussion in COPD. No information exists regarding this aspect of the disease from an unselected COPD population. We assessed acute bronchodilator responsiveness and factors influencing it in subjects with and without airway obstruction in an epidemiologic sample. METHODS: COPD was defined by GOLD criteria (post-bronchodilator FEV(1)/FVC<0.70). In this analysis, subjects with pre-bronchodilator FEV(1)/FVC <0.70 but > or =0.70 post-bronchodilator were considered to have reversible obstruction. Bronchodilator responsiveness after albuterol 200microg was assessed using three definitions: a) FVC and/or FEV(1) increment > or =12% plus > or =200mL over baseline; b) FEV(1)> or =15% increase over baseline; and c) FEV(1) increase > or =10% of predicted value. RESULTS: There were 756 healthy respiratory subjects, 481 subjects with reversible obstruction and 759 COPD subjects. Depending on the criterion used the proportion of person with acute bronchodilator responsiveness ranged between 15.0-28.2% in COPD, 11.4-21.6% in reversible obstructed and 2.7-7.2% in respiratory healthy. FEV(1) changes were lower (110.6+/-7.40 vs. 164.7+/-11.8mL) and FVC higher (146.5+/-14.2mL vs. -131.0+/-19.6mL) in COPD subjects compared with reversible obstructed. Substantial overlap in FEV(1) and FVC changes was observed among the groups. Acute bronchodilator responsiveness in COPD persons was associated with less obstruction and never smoking. CONCLUSIONS: Over two-thirds of persons with COPD did not demonstrate acute bronchodilator responsiveness. The overall response was small and less than that considered as significant by ATS criteria. The overlap in FEV(1) and FVC changes after bronchodilator among the groups makes it difficult to determine a threshold for separating them.
Asunto(s)
Bronquios/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Anciano , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Análisis MultivarianteRESUMEN
BACKGROUND: The PLATINO project was launched in 2002 in order to study the prevalence of chronic obstructive pulmonary disease (COPD) in Latin America. Because smoking is the main risk factor for COPD, detailed data on it were obtained. The aim of this paper was to evaluate the prevalence of smoking and incidence of initiation among middle-aged and older adults (40 years or older). Special emphasis was given to the association between smoking and schooling. METHODS: PLATINO is a multicenter study comprising five cross-sectional population-based surveys of approximately 1,000 individuals per site in Sao Paulo (Brazil), Santiago (Chile), Mexico City (Mexico), Montevideo (Uruguay) and Caracas (Venezuela). The outcome variable was smoking status (never, former or current). Current smokers were those who reported to smoke within the previous 30 days. Former smokers were those who reported to quit smoking more than 30 days before the survey. Using information on year of birth and age of smoking onset and quitting, a retrospective cohort analysis was carried out. Smoking prevalence at each period was defined as the number of subjects who started to smoke during the period plus those who were already smokers at the beginning of the period, divided by the total number of subjects. Incidence of smoking initiation was calculated as the number of subjects who started to smoke during the period divided by the number of non-smokers at its beginning. The independent variables included were sex, age and schooling. RESULTS: Non-response rates ranged from 11.1% to 26.8%. The prevalence of smoking ranged from 23.9% (95%CI 21.3; 26.6) in Sao Paulo to 38.5% (95%CI 35.7; 41.2) in Santiago. Males and middle-aged adults were more likely to smoke in all sites. After adjustment for age, schooling was not associated with smoking. Using retrospective cohort analysis, it was possible to detect that the highest prevalence of smoking is found between 20-29 years, while the highest incidence is found between 10-19 years. Age of smoking onset tended to decline over time among females. CONCLUSION: The prevalence of smoking varied considerably across sites, but was lower among countries with national anti-smoking campaigns.
Asunto(s)
Fumar/epidemiología , Adulto , Edad de Inicio , Escolaridad , Femenino , Encuestas Epidemiológicas , Humanos , Incidencia , América Latina/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Factores Sexuales , Salud UrbanaRESUMEN
BACKGROUND: Although tobacco smoke is the main cause of COPD, relatively little attention has been paid to its potential damage to skeletal muscle. This article addresses the effect of smoking on skeletal muscle. METHODS: The vastus lateralis muscle was studied in 14 non-COPD smokers (FEV(1)/FVC, 78 +/- 5%) and 20 healthy control subjects (FEV(1)/FVC, 80 +/- 3%). Muscular structure, enzyme activity, constitutive and inducible nitric oxide (NO) synthases (endothelial NO oxide synthase [eNOS], neuronal NO synthase [nNOS] and inducible NO synthase [iNOS]), nitrites, nitrates, nitrotyrosine, and the presence of macrophages were analyzed. RESULTS: In smokers, type I muscle fibers cross-sectional area was decreased, and a similar trend was found in type IIa fibers. Lactate dehydrogenase levels and the percentage of fibers with low oxidative and high glycolytic capacity were increased in smokers. nNOS (96.9 +/- 11.7 vs 125.4 +/- 31.9 ng/mg protein; p < 0.01) and eNOS (38.9 +/- 11.0 vs 45.2 +/- 7.7 ng/mg protein [+/- SD]; p < 0.05) were lower in smokers, while fiber type distribution, capillarity measures, beta-hydroxy-acyl-CoA-dehydrogenase levels, iNOS, nitrite, nitrate, and nitrotyrosine levels, and macrophage number in the muscle tissue were similar to the nonsmoker subjects. CONCLUSIONS: Smokers presented some alterations of skeletal muscle such as oxidative fiber atrophy, increased glycolytic capacity, and reduced expression of the constitutive NO synthases (eNOS and nNOS). The findings support some muscular structural and metabolic damage but not the presence of local inflammation in the smokers. In addition, they suggest a possible effect of tobacco smoke impairing the normal process of NO generation.
Asunto(s)
Músculo Esquelético/enzimología , Músculo Esquelético/patología , Fumar/efectos adversos , Humanos , Persona de Mediana Edad , Óxido Nítrico Sintasa/metabolismoRESUMEN
BACKGROUND: The body mass index (BMI) is a prognostic factor for chronic obstructive pulmonary disease (COPD). Despite its importance, little information is available regarding BMI alteration in COPD from a population-based study. We examined characteristics by BMI categories in the total and COPD populations in five Latin-American cities, and explored the factors influencing BMI in COPD. METHODS: COPD was defined as a postbronchodilator forced expiratory volume in the first second/forced vital capacity (FEV(1)/FVC) <0.70. BMI was categorized as underweight (< 20 kg/m(2)), normal weight (20-24.9 kg/m(2)), overweight (25.0-29.9 kg/m(2)), and obese (> or = 30.0 kg/m(2)). RESULTS: Interviews were completed in 5571 subjects from 6711 eligible individuals, and spirometry was performed in 5314 subjects. There were 759 subjects with COPD and 4555 without COPD. Compared with the non-COPD group, there was a higher proportion of COPD subjects in the underweight and normal weight categories, and a lower proportion in the obese category. Over one-half COPD subjects had BMI over 25 kg/m(2). No differences in BMI strata among countries were found in COPD subjects. Factors associated with lower BMI in males with COPD were aging, current smoking, and global initiative for chronic obstructive lung disease (GOLD) stages III-IV, whereas wheeze and residing in Santiago and Montevideo were associated with higher BMI. In females with COPD, current smoking, lower education, and GOLD stages II-IV were associated with lower BMI, while dyspnea and wheeze were associated with higher BMI. CONCLUSIONS: BMI alterations are common in COPD with no significant differences among countries. Current smoking, age, GOLD stages, education level, residing in Santiago and Montevideo, dyspnea and wheeze were independently associated with BMI in COPD.
Asunto(s)
Índice de Masa Corporal , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Adulto , Anciano , Envejecimiento , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Ciudades , Disnea , Escolaridad , Femenino , Humanos , América Latina , Masculino , Persona de Mediana Edad , Análisis de Regresión , Ruidos Respiratorios , Riesgo , FumarRESUMEN
OBJECTIVE: PLATINO project is a population-based study designed to determine the prevalence of chronic obstructive pulmonary disease (COPD) in São Paulo, Brazil; Mexico City, Mexico; Montevideo, Uruguay; Santiago de Chile, Chile; and Caracas, Venezuela. The objective of this portion of PLATINO was to describe preventive and pharmacological treatment of COPD patients and factors associated with such treatment. PATIENTS AND METHODS: Eligible subjects completed a questionnaire and underwent postbronchodilator spirometry. RESULTS: Of the total of 5529 individuals who answered items referring to treatment, 758 had COPD (ratio of postbronchodilator forced expiratory volume in 1 second to forced vital capacity of <0.7), and 86 of them had been previously diagnosed by a physician. Among all COPD patients, only half of smokers or former smokers had been advised to quit and 24.7% had received some type of respiratory medication. Only 13.5% had used inhaled corticosteroids, and those were the patients with the most severe disease. In the group of patients who had a previous medical diagnosis of COPD, 69% of the smokers or former smokers had been advised to quit by a physician and 75.6% had received respiratory medication in the preceding year: 43% reported having used inhaled medication and 36% had used bronchodilators. Rates of vaccination against influenza and the use of mucolytic drugs and inhalers varied from one health care facility to another. All drug prescriptions were based on previous spirometry. CONCLUSIONS: Spirometry emerged not only as a diagnostic tool, but also as a factor associated with treatment, against a background of uneven use of available health care resources in these 5 Latin American cities.
Asunto(s)
Antiinflamatorios/uso terapéutico , Broncodilatadores/uso terapéutico , Expectorantes/uso terapéutico , Enfermedad Pulmonar Obstructiva Crónica/terapia , Espirometría/métodos , Vacunación/métodos , Adulto , Anciano , Femenino , Humanos , Gripe Humana/inmunología , Gripe Humana/prevención & control , América Latina , Masculino , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Índice de Severidad de la Enfermedad , Fumar/epidemiología , Encuestas y CuestionariosRESUMEN
BACKGROUND: COPD is a major worldwide problem with a rising prevalence. Despite its importance, there is a lack of information regarding underdiagnosis and misdiagnosis of COPD in different countries. As part of the Proyecto Latinoamericano de Investigación en Obstrucción Pulmonar study, we examined the relationship between prior diagnostic label and airway obstruction in the metropolitan areas of five Latin American cities (São Paulo, Santiago, Mexico City, Montevideo, and Caracas). METHODS: A two-stage sampling strategy was used in each of the five areas to obtain probability samples of adults aged >or= 40 years. Participants completed a questionnaire that included questions on prior diagnoses, and prebronchodilator and postbronchodilator spirometry. A study diagnosis of COPD was based on airway obstruction, defined as a postbronchodilator FEV(1)/FVC < 0.70. RESULTS: Valid spirometry and prior diagnosis information was obtained for 5,303 participants; 758 subjects had a study diagnosis of COPD, of which 672 cases (88.7%) had not been previously diagnosed. The prevalence of undiagnosed COPD was 12.7%, ranging from 6.9% in Mexico City to 18.2% in Montevideo. Among 237 subjects with a prior COPD diagnosis, only 86 subjects (36.3%) had postbronchodilator FEV(1)/FVC < 0.7, while 151 subjects (63.7%) had normal spirometric values. In the same group of 237 subjects, only 34% reported ever undergoing spirometry prior to our study. CONCLUSIONS: Inaccurate diagnostic labeling of COPD represents an important health problem in Latin America. One possible explanation is the low rate of spirometry for COPD diagnosis.
Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Adulto , Brasil/epidemiología , Chile/epidemiología , Femenino , Humanos , Modelos Logísticos , Masculino , México/epidemiología , Prevalencia , Factores de Riesgo , Muestreo , Espirometría , Población Urbana , Uruguay/epidemiología , Venezuela/epidemiologíaRESUMEN
OBJECTIVE: The criteria for disease severity established by the Global Initiative for Chronic Obstructive Lung Disease are based on forced expiratory volume in 1 second (FEV1) expressed as a percentage of the predicted value after application of a bronchodilator. This study aims to determine postbronchodilator spirometry reference values. SUBJECTS AND METHODS: A cluster sample of subjects aged 40 years or over was chosen to be representative of the metropolitan areas of 5 Latin American cities (São Paulo, Mexico City, Montevideo, Santiago, and Caracas). Spirometry was performed on 5183 subjects following the recommendations of the American Thoracic Society before and after inhalation of 200 microg of salbutamol. Multiple linear regression equations were fitted for the postbronchodilator spirometric values-FEV1, forced expiratory volume in 6 seconds (FEV6), peak expiratory flow rate, forced vital capacity (FVC), FEV1/FEV6, FEV1/FVC and forced expiratory flow between 25% and 75% of vital capacity (FEF25-75). These were adjusted for sex, age, and height in 887 asymptomatic subjects with no history of lung disease. RESULTS: The postbronchodilator reference values for FEV1, FEV1/FVC, and FEV1/FEV6 were on average 3% higher than those obtained before bronchodilation. This apparently small difference caused an upward shift in the 5th percentile (lower limit of normal) of the predicted values. When prebronchodilation instead of postbronchodilation reference values were used, 3.2% of the results for airflow obstruction in our population of over-40-year-olds were false negatives. CONCLUSIONS: The reported reference values are more appropriate for postbronchodilator spirometry and make it possible to reduce the number of misclassifications.
Asunto(s)
Albuterol/administración & dosificación , Broncodilatadores/administración & dosificación , Espirometría , Administración por Inhalación , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de ReferenciaRESUMEN
BACKGROUND: Both the prevalence and mortality attributable to chronic obstructive pulmonary disease (COPD) seem to be increasing in low-income and middle-income countries, but few data are available. The aim of the PLATINO study, launched in 2002, was to describe the epidemiology of COPD in five major Latin American cities: São Paulo (Brazil), Santiago (Chile), Mexico City (Mexico), Montevideo (Uruguay), and Caracas (Venezuela). METHODS: A two-stage sampling strategy was used in the five areas to obtain probability samples of adults aged 40 years or older. These individuals were invited to answer a questionnaire and undergo anthropometry, followed by prebronchodilator and postbronchodilator spirometry. We defined COPD as a ratio less than 0.7 of postbronchodilator forced expiratory volume in the first second over forced vital capacity. FINDINGS: Complete information, including spirometry, was obtained from 963 people in São Paulo, 1173 in Santiago, 1000 in Mexico City, 885 in Montevideo, and 1294 in Caracas. Crude rates of COPD ranged from 7.8% (78 of 1000; 95% CI 5.9-9.7) in Mexico City to 19.7% (174 of 885; 17.2-22.2) in Montevideo. After adjustment for key risk factors, the prevalence of COPD in Mexico City remained significantly lower than that in other cities. INTERPRETATION: These results suggest that COPD is a greater health problem in Latin America than previously realised. Altitude may explain part of the difference in prevalence. Given the high rates of tobacco use in the region, increasing public awareness of the burden of COPD is important.
Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica/etiología , Fumar/efectos adversos , Adulto , Femenino , Humanos , América Latina/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Pruebas de Función Respiratoria , Factores de Riesgo , Encuestas y Cuestionarios , Población UrbanaRESUMEN
STUDY OBJECTIVE: The present study evaluated the relationship between health status (HS) and peripheral muscle histochemical characteristics in chronic obstructive pulmonary disease (COPD), and identified selected independent respiratory and extrapulmonary variables that predicted the HS of these patients. DESIGN: Cross-sectional study. SETTING: Outpatient respiratory clinic of a university hospital. PATIENTS AND METHODS: We studied 29 patients (63+/-10 yrs) with a forced expiratory volume in 1s (FEV1) of 39+/-12%. All patients underwent vastus lateralis muscle biopsies for histochemical analysis. They also had spirometry, arterial blood gas analysis, body mass index (BMI), dyspnea determined with the MMRC scale and responded to the St. George's Respiratory Questionnaire (SGRQ) for HS assessment. RESULTS: SGRQ total score correlated with fiber type distribution. A stepwise multiple regression identified three independent predictors of SGRQ total score: type I fiber proportion, BMI, and FEV1; r = 0.78 and r2 = 0.61. CONCLUSIONS: These results indicate that impaired HS in COPD is related to the peripheral muscle changes characterized by less type I fibers proportion. The findings argue in favor of an important contribution of the systemic consequences on the HS in COPD independently from the airflow limitation severity, and help to explain the observation of the poor correlation between the degree of airflow limitation and SGRQ total score.
Asunto(s)
Estado de Salud , Enfermedad Pulmonar Obstructiva Crónica/patología , Músculo Cuádriceps/patología , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja , Análisis de los Gases de la Sangre , Índice de Masa Corporal , Disnea/patología , Volumen Espiratorio Forzado/fisiología , Humanos , Persona de Mediana Edad , Capacidad Vital/fisiologíaRESUMEN
BACKGROUND: We report the performance of an ultrasound-based portable spirometer (EasyOne) used in a population-based survey of the prevalence of chronic obstructive pulmonary disease, conducted in 5 Latin American cities: São Paulo, Brazil; México City, México; Montevideo, Uruguay; Santiago, Chile; and Caracas, Venezuela (the Latin American COPD Prevalence Study [PLATINO]). METHODS: During the survey period (which ranged from 3 months to 6 months in the various locations) we collected daily calibration data from the 70 EasyOne spirometers used in the 5 survey cities. The calibrations were conducted with a 3-L syringe, and the calibration data were stored in the spirometer's database. RESULTS: Ninety-seven percent of the calibration volumes were within +/- 64 mL (2.1%) of the 3-L calibration signal. Excluding data from the first city studied (São Paulo), where one calibration syringe had to be replaced, 98% of the calibration checks were within +/- 50 mL (1.7%). The measured volume was affected only minimally by the syringe's peak flow or emptying time. CONCLUSION: In these 70 EasyOne spirometers neither calibration nor linearity changed during the study. Such calibration stability is a valuable feature in spirometry surveys and in the clinical setting.
Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Espirometría/instrumentación , Brasil/epidemiología , Calibración , Chile/epidemiología , Humanos , México/epidemiología , Prevalencia , Uruguay/epidemiología , Venezuela/epidemiologíaRESUMEN
OBJECTIVE: In clinical practice, spirometry is a extremely useful test that requires strict quality control, an appropriate strategy for interpretation, and reliable reference values. The aim of this study was to report spirometric reference values for 5 cities in Latin America. PATIENTS AND METHODS: From data for 5315 subjects who had undergone spirometry in the PLATINO study in Caracas, Mexico City, Santiago, São Paulo, and Montevideo, we selected information for 906 (17%) individuals aged between 40 years and 90 years to provide reference values. The chosen subjects had never smoked, were asymptomatic, had not been diagnosed with lung disease, and were not obese. Multiple regression models were constructed with the following spirometric parameters: forced expiratory volume in 1 second (FEV1) and in 6 seconds (FEV6), peak expiratory flow, forced vital capacity (FVC), FEV1/FEV6, FEV1/FVC, and forced midexpiratory flow rate. Height, sex, and age were also included in the model. RESULTS: Average values for the subjects studied were similar to those for the white North American population and the Mexican-American population of the third National Health and Nutrition Examination Survey, but exceeded those of the black population of the same survey by 20%. CONCLUSIONS: The proposed reference values are an improvement on those currently available for Latin America because the participants were chosen by population sampling methods and standardized up-to-date methodology was used.
Asunto(s)
Espirometría/normas , Adulto , Negro o Afroamericano , Factores de Edad , Anciano , Anciano de 80 o más Años , Altitud , Antropometría , Brasil , Chile , Etnicidad , Europa (Continente) , Femenino , Volumen Espiratorio Forzado , Humanos , América Latina , Masculino , Americanos Mexicanos , México , Persona de Mediana Edad , Valores de Referencia , Muestreo , Factores Sexuales , Población Urbana , Uruguay , Venezuela , Capacidad Vital , Población BlancaRESUMEN
The pressure-time index (PTI = Pmouth/Pi max x Ti/Ttot) has been validated by Ramonatxo (J. Appl. Physiol. 78 (1995) 646 and by Jabour (Am. Rev. Respir. Dis. 144 (1991) 531 as a noninvasive tool for the assessment of inspiratory muscles load. Nobody until now has evaluated the correlation between the PTI and diaphragmatic activity. Further, the PTI has not been compared with another measures of respiratory muscle load such as the transdiaphragmatic pressure index or TTdi. The purpose of our study was to test the hypothesis that the PTI measured at the mouth (PTIm) is a noninvasive reflection of TTdf and electromyographic activity of the diaphragm (EMGdf). We studied 6 patients with COPD and 5 normal individuals at rest and during a CO2 rebreathing trial and simultaneously measured PTIm, TTdi and EMGdi. The curves of PTIm and EMGdi follows the same trend during the CO2 rebreathing trial with strong and significant correlation between these parameters (r = 0.89 P < 0.05 and r = 0.82 P < 0.05 for PaCO2 of 45 and 53 mmHg respectively). We conclude that PTIm measured as Pmouth/Pi max x Ti/Ttot is an adequate noninvasive method that reflect not only the diaphragmatic activity but also the inspiratory muscles load.
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Boca/fisiología , Músculos Respiratorios/fisiología , Anciano , Dióxido de Carbono/fisiología , Electromiografía , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Masculino , Persona de Mediana Edad , Presión , Intercambio Gaseoso Pulmonar/fisiología , Capacidad Vital/fisiologíaRESUMEN
BACKGROUND: The PLATINO baseline study, conducted from 2003-2005 in five Latin American cities (São Paulo, Mexico City, Montevideo, Santiago, Caracas), showed a high prevalence of chronic obstructive pulmonary disease (COPD). METHODS/DESIGN: A follow-up study was conducted in three out of the five centers (Montevideo, Santiago, and São Paulo) after a period of 5, 6 and 9years, respectively, aimed at verifying the stability of the COPD diagnosis over time, the evolution of the disease in terms of survival, morbidity and respiratory function, and the analyses of inflammatory and genetic biomarkers in the blood. Some questions were added to the original questionnaire and death certificates were obtained from the national official registries. RESULTS: The fieldwork has been concluded in the three centers. From the original samples in the PLATINO study phasei, we were able to locate and interview 85.6% of patients in Montevideo, 84.7% in Santiago and 77.7% in São Paulo. Individuals who could not be located had higher education levels in Brazil, and were more likely to be current smokers in Santiago and São Paulo than in Montevideo. The overall quality of spirometries was ≥80% according to American Thoracic Society criteria. The number of deaths was 71 (Montevideo), 95 (Santiago) and 135 (São Paulo), with death certificates obtained from the national mortality registries for 76.1%, 88.3% and 91.8% of cases in Montevideo, Santiago and São Paulo, respectively. CONCLUSIONS: This study shows that is possible to perform population-based longitudinal studies in Latin American with high follow-up rates and high-quality spirometry data. The adequacy of national mortality registries varies among centers in Latin America.
Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Adulto , Anciano , Recolección de Muestras de Sangre , Índice de Masa Corporal , Estudios de Cohortes , Certificado de Defunción , Femenino , Estudios de Seguimiento , Humanos , América Latina/epidemiología , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Sistema de Registros , Fumar/epidemiología , Factores Socioeconómicos , Espirometría , Encuestas y Cuestionarios , Población Urbana/estadística & datos numéricos , Circunferencia de la CinturaRESUMEN
BACKGROUND: Several COPD phenotypes have been described; the COPD-asthma overlap is one of the most recognized. The aim of this study was to evaluate the prevalence of three subgroups (asthma, COPD, and COPD-asthma overlap) in the Latin American Project for the Investigation of Obstructive Lung Disease (PLATINO) study population, to describe their main characteristics, and to determine the association of the COPD-asthma overlap group with exacerbations, hospitalizations, limitations due to physical health, and perception of general health status (GHS). METHODS: The PLATINO study is a multicenter population-based survey carried out in five Latin American cities. Outcomes were self-reported exacerbations (defined by deterioration of breathing symptoms that affected usual daily activities or caused missed work), hospitalizations due to exacerbations, physical health limitations, and patients' perception of their GHS obtained by questionnaire. Subjects were classified in three specific groups: COPD--a postbronchodilator (post-BD) FEV1/FVC ratio of < 0.70; asthma--presence of wheezing in the last year and a minimum post-BD increase in FEV1 or FVC of 12% and 200 mL; and overlap COPD-asthma--the combination of the two. RESULTS: Out of 5,044 subjects, 767 were classified as having COPD (12%), asthma (1.7%), and COPD-asthma overlap (1.8%). Subjects with COPD-asthma overlap had more respiratory symptoms, had worse lung function, used more respiratory medication, had more hospitalization and exacerbations, and had worse GHS. After adjusting for confounders, the COPD-asthma overlap was associated with higher risks for exacerbations (prevalence ratio [PR], 2.11; 95% CI, 1.08-4.12), hospitalizations (PR, 4.11; 95% CI, 1.45-11.67), and worse GHS (PR, 1.47; 95% CI, 1.18-1.85) compared with those with COPD. CONCLUSIONS: The coexisting COPD-asthma phenotype is possibly associated with increased disease severity.
Asunto(s)
Asma/epidemiología , Hospitalización/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Adulto , Anciano , Asma/fisiopatología , Comorbilidad , Femenino , Volumen Espiratorio Forzado/fisiología , Encuestas Epidemiológicas , Humanos , América Latina/epidemiología , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Fenotipo , Prevalencia , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Factores de Riesgo , Índice de Severidad de la Enfermedad , Capacidad Vital/fisiologíaRESUMEN
OBJECTIVE: To determine whether the presence of chronic obstructive lung disease (COPD) and reduction of lung function parameters were predictors of mortality in a cohort. MATERIALS/PATIENTS AND METHODS: Population based cohorts were followed in Montevideo, Santiago and Sao Paulo during 5, 6 and 9 years, respectively. Outcomes included all-cause, cardiovascular, respiratory and cancer mortality; exposures were COPD, forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). Cox regression was used for analyses. Sensitivity, specificity, positive and negative predictive values, receiver operator characteristics curves and Youden's index were calculated. RESULTS: Main causes of death were cardiovascular, respiratory and cancer. Baseline COPD was associated with overall mortality (HRâ=â1.43 for FEV1/FVCAsunto(s)
Volumen Espiratorio Forzado
, Enfermedad Pulmonar Obstructiva Crónica/mortalidad
, Enfermedad Pulmonar Obstructiva Crónica/fisiopatología
, Adulto
, Estudios de Cohortes
, Femenino
, Humanos
, Estimación de Kaplan-Meier
, Masculino
, Persona de Mediana Edad
, Valor Predictivo de las Pruebas
, Modelos de Riesgos Proporcionales
, Enfermedad Pulmonar Obstructiva Crónica/diagnóstico
, Enfermedad Pulmonar Obstructiva Crónica/epidemiología
, Curva ROC
, Espirometría
RESUMEN
BACKGROUND: Spirometry is the gold standard for diagnosing chronic obstructive pulmonary disease (COPD). Although there are a number of different guideline criteria for deciding who should be selected for spirometric screening, to date it is not known which criteria are the best based on sensitivity and specificity. AIMS: Firstly, to evaluate the proportion of subjects in the PLATINO Study that would be recommended for spirometry testing according to Global initiative for Obstructive Lung Disease (GOLD)-modified, American College of Chest Physicians (ACCP), National Lung Health Education Program (NLHEP), GOLD and American Thoracic Society/European Respiratory Society (ATS/ERS) criteria. Secondly, we aimed to compare the sensitivity, specificity, and positive predictive and negative predictive values, of these five different criteria. METHODS: Data from the PLATINO study included information on respiratory symptoms, smoking and previous spirometry testing. The GOLD-modified spirometry indication criteria are based on three positive answers out of five questions: the presence of cough, phlegm in the morning, dyspnoea, age over 40 years and smoking status. RESULTS: Data from 5,315 subjects were reviewed. Fewer people had an indication for spirometry (41.3%) according to the GOLD-modified criteria, and more people had an indication for spirometry (80.4%) by the GOLD and ATS/ERS criteria. A low percentage had previously had spirometry performed: GOLD-modified (14.5%); ACCP (13.2%); NLHEP (12.6%); and GOLD and ATS/ERS (12.3%). The GOLD-modified criteria showed the least sensitivity (54.9) and the highest specificity (61.0) for detecting COPD, whereas GOLD and ATS/ERS criteria showed the highest sensitivity (87.9) and the least specificity (20.8). CONCLUSION: There is a considerable difference in the indication for spirometry according to the five different guideline criteria. The GOLD-modified criteria recruit less people with the greatest sum of sensitivity and specificity.
Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Espirometría/normas , Femenino , Humanos , América Latina , Masculino , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: One of the gene polymorphisms often studied in asthmatic patients is the ß2 adrenergic receptor (ADRß2). Even though in the Venezuelan Mestizo population there is a high incidence of asthma, there are no direct reports of ADRß2 gene polymorphism, and treatment response. The aim of this study was to assess, in this population, the gene frequency of ADRß2 polymorphisms at codons 16 Arg/Gly and 27 Gln/Glu, allergen sensitization, and its relationship to bronchodilator response. METHODS: Purified genomic DNA was obtained form 105 Mestizo asthmatic and 100 Mestizo healthy individuals from Venezuela. The two polymorphisms were assessed by PCR-RFLP. Patient sensitization to aeroallergens and their response to bronchodilatation were correlated. RESULTS: Significant differences between patients and controls were recorded in: 1) the prevalence of Arg/Arg at codon 16 (28.6% in patients vs. 47% in controls, P<0.01), 2) the frequency of heterozygotes Arg/Gly (55% in patients vs. 35% in controls, P<0.01). Conversely, no differences in polymorphism frequencies were found at codon 27. The haplotypes Arg/Gly-Gln/Gln were more common in patients than controls (P <0.01), whereas the Arg/Arg-Gln/Glu combination prevailed in the control group (P<0.01). The Arg/Gly and Gln/Glu genotypes were associated with better responses after salbutamol. The asthmatic homozygotes Arg/Arg have higher sensitivity to aeroallergens. CONCLUSION: The difference in Arg/Arg frequency between groups suggests that this could be a protective genotype although the asthmatic group had a higher sensitivity to aeroallergens. The asthmatic heterozygotes had better bronchodilator responses than the homozygotes.
Asunto(s)
Asma/tratamiento farmacológico , Asma/genética , Broncodilatadores/uso terapéutico , Polimorfismo Genético , Receptores Adrenérgicos beta 2/genética , Adulto , Codón/genética , Femenino , Humanos , Masculino , VenezuelaRESUMEN
INTRODUCTION: Comorbidities are common in patients with chronic obstructive pulmonary disease (COPD), and have a significant impact on health status and prognosis. The PLATINO study provides data on self-reported comorbidities and perceived health status in COPD subjects. METHODS: PLATINO is a population-based study on COPD prevalence in five Latin American cities. COPD diagnosis was defined by GOLD criteria (FEV1/FVC<.70 post-bronchodilator). Information was collected on the following comorbidities: heart disease, hypertension, diabetes, cerebrovascular disease, peptic ulcer and asthma. Health status was evaluated using the SF-12 questionnaire, derived from the question: «In general, would you say your health is excellent, very good, good, fair or poor?¼. A simple comorbidity score was calculated by adding the total number of comorbid conditions. RESULTS: Of a total population of 5314individuals, 759 had COPD. Reported comorbidities by decreasing frequency were: any cardiovascular disease, hypertension, peptic ulcer, heart disease, diabetes, cerebrovascular disease, asthma and lung cancer. COPD patients had a higher comorbidity score and prevalence of lung cancer (P<.0001) and asthma (P<.0001), as well as a higher tendency to have hypertension (P=.0652) and cerebrovascular disease (P=.0750). Factors associated with comorbidities were age, body mass index (BMI) and female gender. The number of comorbidities increased as the health status deteriorated. CONCLUSIONS: In the PLATINO population-based study, COPD individuals had an increased number of comorbidities. Age, female gender and higher BMI were the factors associated with comorbidity in these patients. Comorbid conditions were associated with impaired health status, independently of the COPD status.