Longitudinal analysis of peak expiratory flow (PEF) and cognition in 14 countries

Accelerated longitudinal model from 43 to 97 years

Lower PEF associated with reduced cognitive performance across multiple domains

PEF not associated with cognitive decline, indicating stable pre-existing differences

The number of older people with cognitive impairment is increasing worldwide. Impaired lung function might be associated with cognitive decline in older age; however, results from large longitudinal studies are lacking. In this study, we examined the longitudinal associations between pulmonary function and the trajectories of cognitive decline using prospective population-based SHARE data from 14 countries.

The analytic sample included N = 32,049 older adults (Mean age at baseline = 64.76 years). The dependent variable was cognitive performance, measured repeatedly across six waves in three domains: verbal fluency, memory, and numeracy. The main predictor of interest was peak expiratory flow (PEF). The data were analyzed in a multilevel accelerated longitudinal design, with models adjusted for a variety of covariates.

A lower PEF score was associated with lower cognitive performance for each domain as well as a lower global cognitive score. These associations remained statistically significant after adjusting for all covariates Q4 vs Q1 verbal fluency: unstandardized coefficient B = -3.15; numeracy: B = -0.52; memory: B = -0.64; global cognitive score B = −2.65, all p < .001). However, the PEF score was not found to be associated with the rate of decline for either of the cognitive outcomes.

In this large multi-national longitudinal study, the PEF score was independently associated with lower levels of cognitive functions, but it did not predict a future decline. The results suggest that pre-existing differences in lung functions are responsible for variability in cognitive functions and that these differences remained stable across aging.

Pulmonary function

Peak expiratory flow

Cognitive decline

Cross-cultural

Longitudinal

© 2024 The Authors. Published by Elsevier Inc.