Screening tool for restrictive and obstructive ventilatory abnormalities in a population-based survey

Abstract Background: A 6 s spirometry with an inexpensive pocket spirometer efficiently selects individuals for a diagnostic-quality spirometry for airflow limitation, but could also be useful to identify individuals with a restrictive pattern. Objectives: We evaluated an inexpensive simplified spirometer (chronic obstructive pulmonary disease [COPD]-6) as a screening tool to identify spirometric abnormalities. Methods: A population-based survey in Mexico City, with 742 participants performing pre- and post-BD spirometry and a three-maneuver 6 s spirometry (pre-BD) with a COPD-6. We evaluated forced expiratory volume in 1 s (FEV1), FEV6, and FEV1/FEV6 from the COPD-6, crude and expressed as the percentage of predicted (%P), to discriminate post-bronchodilator airflow obstruction (FEV1/forced vital capacity [FVC] <5th percentile) or restriction (FVC or FEV1 <5th percentile with normal FEV1/FVC) through receiver operating characteristics and their area under the curve (AUC). Results: FEV1%P was the best predictor to identify pre- and post-BD ventilatory abnormalities (best cutoff point 87%P, AUC 92% for restrictive pattern, 89% for obstructive pattern, and 91% for any spirometric abnormality). Deriving to clinical spirometry only those with <87%P (26% of the sample) missed only 12% of spirometric abnormalities most of the latter mild. Conclusions: An FEV1 <87%P from a pre-BD 6 s spirometry correctly identified individuals with spirometric ventilatory defects, either obstructive or restrictive.

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

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

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