Prediction equations for spirometric parameters in Mexican adult population

BACKGROUND: Our objective was to develop prediction equations for spirometric parameters that included the following: forced vital capacity (FVC); 1st-sec forced expiratory volume (FEV1); FEV1/FVC ratio; peak expiratory flow (PEF); maximal expiratory flow 50% FVC (VF50) and maximal expiratory flow 75% FVC (VF75); maximal mid-expiratory flow (FEF25-75), and forced late expiratory flow rate (FEF75-85) in a sample of adult Mexican population of both sexes. Age and height variables were utilized. METHODS: Spirometric studies were carried out, observing the international recommendations and norms in force and effected under basal conditions and post-bronchodilator. Linear regression equations were generated based on gender, age, and height. For each spirometric parameter, we selected a linear model. Studies were carried out with spirometry that was in agreement with quality criteria recommended by the American Thoracic Society (ATS). Bronchodilatator administration allowed for elimination of subjects with subclinical bronchial hyperreactivity RESULTS: We studied 436 patients with normal clinical radiographic and pulmonary function, with negative smoking and age range between 17 and 63 years; 206 were females and 230, males. Linear regression equations obtained had direct linear correlation with height and inverse linear correlation with age; in addition, equations had a determination coefficient equal to or less than those reported by authors recommended by the ATS. CONCLUSIONS: Equations obtained in this study possessed the quality required for application in adult Mexican population exposed or not to occupational and environmental contaminants.