Association Between Pulmonary Function, Respiratory Muscle Strength and Cognitive Function in Chinese...

Decline in pulmonary function (PF) and respiratory muscle strength (RMS) is influenced by environmental and genetic factors and is inconsistently linked to cognitive outcomes. This study explores the associations between PF, RMS, and cognitive function among community-dwelling older adults in China, analyzing interactions with APOE Ɛ4 and the mediating effect of serum total bilirubin.

About 1,081 Hubei Memory and Aging Cohort (HMACS) participants underwent PF (PEF, FEV1 and FVC), RMS (MIP and MEP) assessment, cognitive tests, APOE genotyping, and bilirubin measurement. Multivariate logistic regression and general linear regression were used to analyze associations.

Among 1,081 participants (mean age 70.52 ± 5.55 years), 26.1% had cognitive impairment. Lower PF and RMS scores were associated with cognitive impairment. Higher comprehensive PF (c-PF) and RMS indices protected against cognitive impairment (eg, c-PF: OR = 0.482-0.609, P < 0.05; MEP: OR = 0.464, P = 0.005). PF and RMS indices correlated positively with global cognition, memory, language, and executive function. Sex differences were noted, with males (n = 449, 41.5%) showing associations between MIP/MEP and global cognition, memory, and language, while females (n = 632, 58.5%) showed broader associations. APOE Ɛ4 status (n = 330) did not affect these associations. Serum total bilirubin levels (n = 977) correlated with pulmonary and cognitive function but did not mediate the associations.

PF (especially PEF) and RMS (especially MEP) indices are significantly associated with cognitive function and impairment in older adults, independent of APOE Ɛ4 status. These findings provide biomarkers for assessing cognitive health risk and a basis for interventions targeting PF and RMS to preserve cognitive function.