title: Diagnosis of airway obstruction in the elderly: contribution of the SARA study.
abstract: BACKGROUND
  The choice between lower limit of normal or fixed value of forced expiratory volume in one second/forced vital capacity ratio (FEV(1)/FVC) < 0.70 as the criterion for confirming airway obstruction is an open issue. In this study, we compared the criteria of lower limit of normal and fixed FEV(1)/FVC for diagnosis of airway obstruction, with a focus on healthy elderly people.
  
  
  METHODS
  We selected 367 healthy nonsmoking subjects aged 65-93 years from 1971 participants in the population-based SARA (Salute Respiratoria nell'Anziano, Italian for "Respiratory Health in the Elderly") study, analyzed their spirometric data, and tested the relationship between spirometric indices and anthropometric variables. The lower limit of normal for FEV(1)/FVC was calculated as the fifth percentile of the normal distribution for selected subjects.
  
  
  RESULTS
  While FEV(1) and FVC decreased significantly with aging, the relationship between FEV(1)/FVC and age was not statistically significant in men or women. The lower limit of normal for FEV(1)/FVC was 0.65 in men and 0.67 in women. Fifty-five participants (15%) had FEV(1)/FVC < 0.70 and would have been inappropriately classified as obstructed according to the Global Initiative for Obstructive Lung Disease, American Thoracic Society/European Respiratory Society, and Canadian guidelines on chronic obstructive pulmonary disease. By applying different FEV(1)/FVC thresholds for the different age groups, as previously proposed in the literature, (0.70 for <70 years, 0.65 for 70-80 years, and 0.60 for >80 years) the percentage of patients classified as obstructed decreased to 6%. No subjects older than 80 years had an FEV(1)/FVC < 0.60.
  
  
  CONCLUSIONS
  The present results confirm the inadequacy of FEV(1)/FVC < 0.70 as a diagnostic criterion for airway obstruction after the age of 65 years. FEV(1)/FVC < 0.65 and <0.67 (for men and women, respectively) could identify subjects with airway obstruction in such a population. Further reduction of the threshold after 80 years is not justified.
authors: Biomedical Department of Internal and Specialist Medicine, Section of Pulmonology, University of Palermo, Italy. claudiosorino@libero.it
authors: Claudio
authors: C
authors: Sorino
authors: Salvatore
authors: S
authors: Battaglia
authors: Nicola
authors: N
authors: Scichilone
authors: Claudio
authors: C
authors: Pedone
authors: Raffaele
authors: R
authors: Antonelli-Incalzi
authors: Duane
authors: D
authors: Sherrill
authors: Vincenzo
authors: V
authors: Bellia
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007558:Italy; D008297:Male; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000503:physiopathology; D012129:Respiratory Function Tests / Q000379:methods; D014797:Vital Capacity