Citation

Sprague BN, Phillips CB, Ross LA. J. Gerontol. B Psychol. Sci. Soc. Sci. 2019; 74(5): 772-784.

Affiliation

Department of Human Development and Family Studies, The Pennsylvania State University, University Park.

Copyright

(Copyright © 2019, Gerontological Society of America, Publisher Oxford University Press)

DOI

10.1093/geronb/gbx126

PMID

29121330

Abstract

OBJECTIVES: There are positive relationships between physical and cognitive function in older adulthood; however, the strength of these relationships are inconsistent across studies. Although novel statistical tools provide flexibility to explore age-related differences in relationship magnitude, such methods have not been implemented in gerontological research. This study applied such methods to examine variations in relationship magnitude between physical function and cognition in healthy older adults (N = 2,783).

METHOD: Time-varying effects modeling (TVEM) is an extension of regression that models changes in relationships as a function of time-varying metrics like age. TVEM was used to examine if physical function (Turn 360, grip strength) predicted cognitive performance (memory, processing speed/attention, and reasoning) similarly across adults aged 65-90.

RESULTS: All associations between Turn 360 and all cognitive domains were significant and positive; however, speed of processing had significant magnitude variation across age such that the young-old and the old-old demonstrated the strongest relationships. Associations between grip strength and all cognitive domains significantly strengthened with increased age.

DISCUSSION: Results suggest that depending on the sample age, there may be inconsistencies in the relationships between physical and cognitive performance. Future research should explore these relationships longitudinally to better elucidate discrepant findings.

Language: en

Keywords

Balance; Cognitive aging; Strength; Time-varying effects modeling