Association of anterior cingulate glutathione with sleep apnea in older adults at-risk for dementia

Shantel L. Duffy*, Jim Lagopoulos, Zoe Terpening, Simon J G Lewis, Ron Grunstein, Loren Mowszowski, Nathan Cross, Daniel F. Hermens, Ian B. Hickie, Sharon L. Naismith

*Corresponding author for this work

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

Study Objectives: Sleep disordered breathing (SDB) is common in older adults and is strongly associated with cognitive decline, with increasing evidence suggesting that it may represent a risk factor for dementia. Given that SDB is characterized by intermittent episodes of hypoxemia during sleep, it is possible that cognitive impairment may relate to cerebral oxidative stress. This study aimed to examine the relationship between nocturnal markers of hypoxemia and proton magnetic resonance spectroscopy (1H-MRS) markers of oxidative stress within the anterior cingulate cortex (ACC) of the brain. Methods: Twenty-four older adults (mean age = 67.9 y) at-risk for dementia were recruited from our Healthy Brain Ageing Research Clinic. At-risk was defined as participants seeking help for assessment and/or intervention for cognitive decline, including those with subjective and/or objective cognitive complaints. This could occur in the context of prior depression or risk factors (e.g., vascular) for dementia. All participants underwent psychiatric, medical and neuropsychological assessment followed by overnight polysomnography. In addition, participants underwent 1H-MRS to derive levels of ACC metabolite glutathione (GSH) reported as a ratio to creatine (GSH/Cr). Results: Increased levels of GSH/Cr were associated with lower oxygen desaturation (r = -0.54, P = 0.007) and more severe apnea-hypopnea index scores during rapid eye movement sleep (r = 0.42, P = 0.050). In addition, ACC GSH/Cr correlated with poorer executive functioning (i.e., response inhibition: r = -0.49, P = 0.015; set shifting: r = -0.43, P = 0.037). Conclusions: Markers of nocturnal hypoxemia and SDB are associated with cerebral oxidative stress in older people at-risk for dementia, suggesting a potential mechanism by which SDB may contribute to brain degeneration, cognitive decline, and dementia. Further work focused on utilizing this biomarker for the early identification and treatment of this possible modifiable risk factor in older persons is now warranted.

Original languageEnglish
Pages (from-to)899-906
Number of pages8
JournalSleep
Volume39
Issue number4
DOIs
Publication statusPublished - 1 Apr 2016
Externally publishedYes

Keywords

  • Anterior cingulate cortex
  • Executive function
  • Glutathione
  • Oxidative stress
  • Oxygen desaturation
  • Proton magnetic resonance spectroscopy
  • Sleep apnea

Fingerprint Dive into the research topics of 'Association of anterior cingulate glutathione with sleep apnea in older adults at-risk for dementia'. Together they form a unique fingerprint.

Cite this