Gonzalo Valdivia

Chronic obstructive pulmonary disease in five Latin American cities (the PLATINO study): a prevalence study

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.

Tuberculosis and airflow obstruction: evidence from the PLATINO study in Latin America

The aim of the present study was to evaluate the association between history of tuberculosis and airflow obstruction. A population-based, multicentre study was carried out and included 5,571 subjects aged ≥40 yrs living in one of five Latin American metropolitan areas: Sao Paulo (Brazil); Montevideo (Uruguay); Mexico City (Mexico); Santiago (Chile); and Caracas (Venezuela). Subjects performed pre- and post-bronchodilator spirometry and were asked whether they had ever been diagnosed with tuberculosis by a physician. The overall prevalence of airflow obstruction (forced expiratory volume in one second/forced vital capacity post-bronchodilator <0.7) was 30.7% among those with a history of tuberculosis, compared with 13.9% among those without a history. Males with a medical history of tuberculosis were 4.1 times more likely to present airflow obstruction than those without such a diagnosis. This remained unchanged after adjustment for confounding by age, sex, schooling, ethnicity, smoking, exposure to dust and smoke, respiratory morbidity in childhood and current morbidity. Among females, the unadjusted and adjusted odds ratios were 2.3 and 1.7, respectively. In conclusion, history of tuberculosis is associated with airflow obstruction in Latin American middle-aged and older adults.

The chronic bronchitis phenotype in subjects with and without COPD: the PLATINO study

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.

Impact of delirium on short-term mortality in elderly inpatients: a prospective cohort study.

BACKGROUND Delirium is an important problem especially in older medical inpatients. OBJECTIVE The authors asked whether delirium and its duration are associated with higher mortality in a 3-month follow-up period. METHOD In this prospective cohort study, inpatients age 65 and older were assessed every 48 hours with the Confusion Assessment Method. RESULTS Of 542 patients enrolled, 192 (35.4%) developed delirium. After 3 months, mortality in the delirium cohort was 25.9%, and in the nondelirium cohort was 5.8%. Delirium was independently associated with mortality, and increased by 11% for every 48 hours of delirium. CONCLUSION Delirium and increased delirium durations are significantly associated with higher mortality.

Impact of Bronchodilator Use on the Prevalence of COPD in Population-Based Samples

The aim of this study was to describe the impact of using bronchodilators on the prevalence of Chronic Obstructive Pulmonary Disease in a population-based survey (Platino study). A cluster sampling of subjects 40 years of age or older, representative of the metropolitan areas of 5 Latin American cities (Sao Paulo, Mexico, Montevideo, Santiago and Caracas) was chosen. Spirometry according to ATS standards was done before and after inhalation of 200 micrograms of salbutamol in 5183 subjects. Prevalences of airflow obstruction were estimated using different criteria, in tests done before and after bronchodilator use, and with reference values for pre- or post-bronchodilator use. Bronchodilator testing reduced the overall prevalence of FEV1/FVC% < 0.70 from 21.7% to 14% (35%). In the group with FEV1/FVC < 0.70 after bronchodilator use, 21% were asymptomatic from the respiratory point of view, and lacked significant adverse exposures. Subjects below the 5th percentile for FEV1/FVC and FEV1/FEV6 were fewer than those with FEV1/FVC < 0.70, especially among the elderly. More subjects are below the 5th percentile of FEV1/FVC and FEV1/FEV6 using reference values for tests after bronchodilator use than using the reference values determined without bronchodilator testing. Testing after bronchodilator use reduces the prevalence of airflow obstruction from 32 to 39% depending on the definition used. In addition, the subjects who were still obstructed after bronchodilator use were the ones who showed more respiratory symptoms and exposure to tobacco and other smokes and dusts, than subjects with reversible obstruction, suggesting an increased specificity for COPD.

Valores de referencia espirométrica en 5 grandes ciudades de Latinoamérica para sujetos de 40 o más años de edad

Objetivo La espirometria es una prueba de gran utilidad clinica, que requiere un estricto control de calidad, una estrategia de interpretacion y valores de referencia adecuados. El proposito del presente trabajo es comunicar los valores de referencia para la espirometria en 5 ciudades de Latinoamerica. Pacientes y metodos El estudio PLATINO se llevo a cabo en Caracas, Mexico, Santiago, Sao Paulo y Montevideo e incluyo a un total de 5.315 sujetos con espirometria realizada. De ellos, se estudio a 906 (17%) que tenian entre 40 y 90 anos de edad para crear valores de referencia, porque nunca habian fumado, estaban asintomaticos y no tenian enfermedad pulmonar diagnosticada ni obesidad. Se efectuaron modelos de regresion multiple con los valores espirometricos –volumen espiratorio forzado en el primer segundo (FEV 1 ) y en 6 s (FEV 6 ), flujo espiratorio maximo, capacidad vital forzada (FVC), FEV 1 /FEV 6 , FEV 1 /FVC y flujo mesoespiratorio forzado–, la talla, el sexo y la edad. Resultados Los sujetos estudiados presentaron en promedio valores similares a los de la poblacion norteamericana blanca y americana de origen mexicano del estudio NHANES III, pero superiores a los de la poblacion negra en un 20%. Conclusiones Los valores de referencia propuestos representan una ventaja sobre los disponibles en la actualidad en Latinoamerica, ya que se eligio a los participantes por metodos de muestreo poblacional y el metodo empleado es estandarizado y actualizado.

Chronic obstructive pulmonary disease and body mass index in five Latin America cities: The PLATINO study

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.

Spirometric Reference Values in 5 Large Latin American Cities for Subjects Aged 40 Years or Over

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.

Prevalence of smoking and incidence of initiation in the Latin American adult population: the PLATINO study

BackgroundThe 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.MethodsPLATINO 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.ResultsNon-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.ConclusionThe prevalence of smoking varied considerably across sites, but was lower among countries with national anti-smoking campaigns.

Frequency of Self-Reported COPD Exacerbation and Airflow Obstruction in Five Latin American Cities: The Proyecto Latinoamericano de Investigación en Obstrucción Pulmonar (PLATINO) Study

BACKGROUND Recurrent exacerbations are common in COPD patients. Limited information exists regarding exacerbation frequency in COPD patients from epidemiologic studies. We examined the frequency of self-reported exacerbations and the factors influencing exacerbation frequency among COPD patients in a population-based study conducted in Latin America. METHODS We used a post-bronchodilator FEV(1)/FVC ratio of < 0.70 to define COPD. Exacerbation was self-reported and defined by symptoms (deterioration of breathing symptoms that affected usual daily activities or caused missed work). RESULTS Spirometry was performed in 5,314 subjects. There were 759 subjects with airflow limitation; of these, 18.2% reported ever having had an exacerbation, 7.9% reported having an exacerbation, and 6.2% reported having an exacerbation requiring at least a doctor visit within the past year. The proportion of individuals with an exacerbation significantly increased by Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages, from 4.2% in stage 1 to 28.9% in stages 3 and 4. The self-reported exacerbation rate was 0.58 exacerbations per year. The rate of exacerbations requiring at least a doctor visit and length of stay in hospital due to exacerbations also increased as COPD severity progressed. The factors associated with having an exacerbation in the past year were dyspnea, prior asthma diagnosis, receiving any respiratory therapy, and disease severity of GOLD stages 3 and 4. CONCLUSIONS The proportion of individuals with airflow limitation and self-reported exacerbation increases as the disease severity progresses. Dyspnea, prior asthma diagnosis, receiving any respiratory therapy, and more severe obstruction were significantly associated with having an exacerbation in the past year.