Limit of normal decline for FEV1.
Hnizdo-E; Yan-T; Sircar-K; Harber-P; Glindmeyer-HW
Proc Am Thorac Soc 2006 Apr; 3(Abstracts):A618
Spirometry monitoring programs often assess year-to-year declines in FEV1 in individuals. The American Thoracic Society (ATS) recommends that a year-to-year decline exceeding 15% be considered clinically important. The American College of Occupational and Environmental Medicine (ACOEM) proposed a limit for a significant decline based on the ATSs 15%. We are evaluating an alternative approach - longitudinal limit of normal decline (LND) based on a one-sided 95% confidence limit. We used data from four monitoring programs with varying data precision to evaluate how well LND agreed with 5th percentiles of observed year-to-year FEV1 declines. We also compared effectiveness of the LND and ACOEM methods for identification of "true" declines >60 mL and >90 mL. Figure shows good agreement between LND values for FEV1 by years of follow-up (lines) and the 5th percentiles for Programs 1-4 using five selected precision periods (large dots) and for Program 4 only (small dots) plotted against program-specific within-person SD. The LND method had higher sensitivity than the ACOEM method, with comparable specificity and predictive values. The LND method was found more effective than the other methods for identifying excessive declines in FEV1.
Spirometry; Monitoring-systems; Sensitivity-testing; Occupational-medicine; Occupational-medicine-programs; Occupational-health; Environmental-medicine; Environmental-health-monitoring; Surveillance
Abstract; Conference/Symposia Proceedings
Issue of Publication
Proceedings of the American Thoracic Society