Mild Cognitive Impairment and Obstructive Sleep Apnea

In this prospective open label clinical trial, primary inclusions were age 55-89 years and
apnea-hypopnea index ≥ 10. Groups were: (1) MCI, OSA, and CPAP adherent (MCI+CPAP); (2) MCI,
OSA, CPAP nonadherent(MCI-CPAP). There were 68 MCI+OSA participants at baseline, and 14 (21%)
dropped out during the 1 year follow-up. At 1 year, n=54, with MCI+CPAP group n=29, and
MCI-CPAP group n=25. Statistically significant improvements in psychomotor/cognitive
processing speed in the MCI+CPAP group versus the MCI-CPAP group were observed at 1 year
after adjustment for age, race, and marital status. There were small to moderate effect sizes
(ES) for memory, attention, daytime sleepiness, and everyday function, favoring the MCI+CPAP
group versus the MCI-CPAP group.

Inclusion criteria

Participants are included in the study if all of the following criteria are met:

(1) Are able to provide written informed consent by self or legally authorized
representative. MacArthur Competency Assessment Tool for Clinical Research (MacCAT-CR) will
be used to assess decision making capacity; (2) OSA defined as an apnea-hypopnea index
(AHI) ≥10, using either a clinical split- or whole-night polysomnography. We chose an AHI
cut-off of ≥10 as opposed to ≥15, the conventional cut-off for moderate OSA because
split-night studies underestimate the AHI; (3) education-adjusted scores of 28-35 on the
modified Telephone Interview for Cognitive Status; (4) 0-0.5 on the Clinical Dementia
Rating (CDR); (5) 24-30 on the Mini-Mental State Examination (MMSE); (6) memory impairment
approximately 1.0-1.5 standard deviations below normal (adjusted for age and education),
determined by scores on the Logical Memory II test; (7) performance approximately 1.0-1.5
standard deviations below normal (adjusted for age and education) in no more than one
cognitive domain in addition to memory; (8) medications stable for at least 4 weeks;
washout from psychoactive medications (e.g., excluded anti-depressants, neuroleptics,
chronic anxiolytics, and sedative hypnotics) for 4 weeks; (9) score of ≤28 on the 21-item
Beck Depression Inventory II; (10) a study partner who spends at least 10 hours per week in
phone or in-person contact with participant; (11) visual and auditory acuity for testing;
(12) 6 or more grades of education completed, or a history to exclude intellectual
disability; and (13) English fluency.

Exclusion criteria

Patients are excluded from participating in this study if 1 or more of the following
criteria are met:

(1) significant neurologic disease other than MCI; (2) MRI exclusions, e.g. metal; (3)
psychiatric disorders, including uncontrolled major depression, bipolar disorder, or
schizophrenia; (4) history of alcohol dependence within 6 months; (5) current significant
unstable medical condition; (6) participation in studies involving neuropsychological
testing; (7) currently receiving CPAP; (8) requiring oxygen during CPAP; (9) dementia
indicated by impairment in 3-5 age and education adjusted cognitive domains.