Expiratory flow limitation and obstruction in the elderly

Elderly people commonly suffer from dyspnoea, which may stem from expiratory flow limitation (EFL). The relationship between EFL, as assessed by the negative expiratory pressure method and spirometric indices, was investigated in an elderly French population. Subjects, aged 66-88 yrs, filled in socio-demographic and standardised questionnaires, which dealt with: medical history, smoking status and respiratory symptoms. EFL measurements and forced expiratory manoeuvres were performed. Validated measurements were obtained in 750 out of 1,318 subjects: 47% were EFL+ (EFL >0), with a higher prevalence in females than in males. EFL and forced expiratory volume in one second (FEV1) were correlated with age. A total of 116, from the 750 subjects, with no medical history and no symptoms, served as a healthy group. The prevalence of EFL+ subjects increased with the grade of dyspnoea and was highest in respiratory and cardiac patients when compared with the healthy subjects. EFL did not correlate with FEV1/forced vital capacity (FVC), the usual index of obstruction. Some elderly subjects (15%) with dyspnoea but with no medical history, mainly females with small FVC and normal FEV1/FVC, had a greater EFL than the healthy subjects. In elderly people, expiratory flow limitation measurements, along with the usual forced expiratory volume in one second/ forced vital capacity ratio, may be of value for the interpretation of dyspnoea.