Regional Gray Matter Volume Links Rest-Activity Rhythm Fragmentation With Past Cognitive Decline

Am J Geriatr Psychiatry. 2020 Feb;28(2):248-251. doi: 10.1016/j.jagp.2019.07.009. Epub 2019 Jul 19.

Abstract

Objectives: We examined the extent to which measures of neurodegeneration and cerebrovascular disease explain the rest-activity rhythm (RAR)-cognition link.

Methods: Seventy participants (mean age at MRI = 86, standard deviation (SD) = 2.6; 53% female) had cognitive, MRI, and accelerometer data. The slope of cognitive decline was defined applying a mixed model to 10 repeated Modified Mini Mental Status Test (3MS) measures over 14 years. Regional gray matter volume (GMV), white matter hyperintensities, and RARs were measured around year 12.

Results: Past 3MS decline was related to RAR fragmentation (per SD β = -0.43, 95% confidence interval: -0.73, -0.14) and lower posterior parietal GMV (per standard deviation β = 0.47, 95% confidence interval: 0.14, 0.79). Higher RAR fragmentation was related to lower posterior parietal GMV (Pearson r = -0.39, n = 70, p = 0.0007), which attenuated the association of RAR fragmentation and past cognitive decline by 17%.

Conclusions: Longitudinal studies are warranted to understand the temporal relations and mechanisms linking RAR fragmentation and neurodegeneration.

Keywords: Rest-activity rhythm; cerebrovascular; cognition; magnetic resonance imaging; neurodegenerative.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Accelerometry
  • Aged, 80 and over
  • Cognition*
  • Cognitive Dysfunction / pathology*
  • Cognitive Dysfunction / physiopathology*
  • Female
  • Gray Matter / pathology*
  • Humans
  • Linear Models
  • Longitudinal Studies
  • Magnetic Resonance Imaging
  • Male
  • Mental Status and Dementia Tests
  • Organ Size