Neuropsychological Test Pattern Associated With a High Percentage of Sleep Apnea Diagnosis

Obstructive sleep apnea (OSA), common in geriatric patients, has been associated with neurocognitive memory disorders such as Alzheimer's disease and other related dementias. An unusual pattern of memory testing has been found to be associated with OSA in a retrospective study (Dexter and Ebert, 2019). This atypical pattern is reported when immediate memory performance is lower than delayed memory performance on the repeatable battery for the assessment of neurological status (RBANS). The current study examines this cognitive testing results pattern coupled with snoring for predicting OSA in geriatric memory patients presenting to a university-based memory clinic.

A convenience sample of patients presenting to the University of Wisconsin Hospitals and Clinics geriatric memory clinic from 2016-2020 for cognitive assessments comprised the study population. Patients completed the mini-mental state examination (MMSE) and obtained a score of 25 out of 30 points or greater and the patients were given the RBANS. Patients were referred for a sleep evaluation if they snored and their immediate memory index score was one or more points lower than their delayed memory index score on the RBANS. No other test score requirements were utilized to trigger the referral.

Of the 251 patients (138 men; 113 women) referred based only on these two criteria to the associated sleep clinic, 158 (80%) were found to have OSA.

The prevalence of positive sleep studies suggests that memory clinic patients who snore and present this unusual pattern of results on the RBANS should be referred for a sleep evaluation for possible OSA.