[Respiration and aging].

Pulmonary aging is a term used to designate age-related alterations in pulmonary function. In includes both respiratory functions (ventilatory mechanics, gas exchange) and non-respiratory functions (immunity) of the lung. The age-related decline in respiratory function is not linear. Generally after 70 years, PaO2 no longer declines and, in elderly men, the FEV1/FVC ratio remains stable. Because of the wide variability of reference values, caution should be taken in interpreting changes in ventilatory mechanics (e.g. spirometry) in elderly people.