Obstructive sleep apnea (OSA) is prevalent among cognitively impaired patients and linked to reduced sleep quality and lowered cognitive capacities. David Colelli (University of Toronto, Canada) presented the results of his research at the virtual AAN 2021 meeting [1].


OSA is a temporary obstruction of the upper respiratory tract during sleep and has been linked to cognitive impairment [2]. The objective testing of OSA had not yet been performed in a population with a diverse range of aetiologies of cognitive impairment. In this study, prevalence of OSA was assessed in 67 cognitively impaired patients (mean age 72.8) in a tertiary care clinic with a home sleep apnea test (HSAT). The aetiologies of cognitive impairment included Alzheimer’s disease, vascular dementia, Parkinson’s disease, and mixed disease. The potential predictors age, sex, neck circumference, sleep quality (actigraphy-derived), and cognitive impairment (assessed through the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE)) were examined and possible associations with OSA severity (defined by the Apnoea-Hypopnoea Index (AHI)) were investigated. Within the study population, 52% of the patients was diagnosed with OSA (AHI ≥5) and 31.3% had moderate or severe OSA (AHI ≥15). Impaired cognitive status (MoCA) was a significant predictor for OSA (defined as an AHI score of ≥15). Pearson correlation analysis showed that more severe OSA was correlated with lower scores on the MoCA and the MMSE. Next to that, decreased sleep efficiency, reduced total sleep time, longer sleep onset latency, and more awakenings were correlated with more severe OSA. In conclusion, results showed that OSA is common among cognitively impaired patients and associated with reduced cognitive fitness and impaired sleep quality.


  1. Colelli DR, et al. Frequency and predictors of obstructive sleep apnea in a cognitively impaired clinic population. S9.003, AAN 2021 Virtual Congress, 17-22 April.
  2. Bradley TD, Floras, JS. Lancet. 2009 Jan 3;373(9657):82-93.