The clinical implications of spirometric impairment in the elderly

Spirometry is a test that measures the breathing capacity. This information is vital for the diagnosis of lung disease and in the assessment of lung health. Spirometry also provides important information on the likelihood of death, heart disease and strokes. The reason for this association is unclear. One possible explanation is that the spirometry measurements be sensitive to the changes of aging (or excessive aging), which is an important risk factor for the development of heart and circulatory diseases. We propose that spirometry can be used as an important marker for the underlying severity of the aging process, and the risks for chronic diseases. We plan to study this, by looking at spirometry measurements and relating it to other measurements of aging and health consequences. Also, we will be developing normal spirometric reference values for age, height and sex that will allow meaningful interpretation of spirometry data.

We looked at the associations between lung function with different measures of physical and cognitive function, self-reported symptoms and perceived health status. We found a consistent dose-response relationship between lower lung function with higher risks of self-reported moderate-severe respiratory symptoms, perceived poor health status and impaired cognition after adjusting extensively for potential confounders. A similar dose-response relationship was also observed between lower lung function with lower physical performance. These associations were invariant across sex, age groups, smoking status and different patterns of lung function impairment. This suggests that these associations are robust and generalizable to the wider population and are independent of lung disease. Furthermore, the close association with virtually all measures which invariably decline with age suggests that lung function may be a sensitive and important marker for excessive ageing.