Abstract
Introduction
Neuroprotection, early diagnosis, and behavioral intervention are national priorities for dementia research. Sleep duration is emerging as an important potential remediable risk factor. In this study, we examined the total sleep time derived from overnight polysomnography (PSG) studies in veterans with a current dementia diagnosis at the time of PSG study (dementia), future diagnosis of dementia following the PSG study (incipient dementia), and no diagnosis of dementia at any time point (no dementia) over a 19-year period.
Methods
We identified 69,847 PSG sleep studies using CPT code 95810 and all-cause dementia diagnosis using ICD 9/10 codes (e.g., F03.90) from 2000-19 in the US Department of Veteran Affairs (VA) national database. To be included patients must have ≥ 1 VA visits in 12 months leading up to PSG. Dementia diagnosis must be documented on two separate visits between 12 months prior to 6 months following PSG for current dementia group and anytime after the PSG for incipient dementia. We used natural language processing to extract TST values from the patient free-text notes. Analysis of variance was used to compare PSG TST of the three groups.
Results
Patients had a mean age of 55.4±13.8 at the time of PSG study, 91.5% were male, and 64% were Caucasian. TST of dementia patients (N=1,031) was m=257±110m (d=0.33, p<.05), incipient dementia (N=1,875) was m=253±116m (d=0.35, p<.05) versus no dementia (61,871) m=292±104mins.
Conclusion
Patients with a diagnosis of dementia at the time of PSG study and patients that went on to receive a diagnosis following their PSG study had a significantly lower total sleep time compared to patients that have never received a dementia diagnosis. This is an important study that compares sleep duration during overnight PSG studies and dementia diagnosis across 19 years in the largest integrated healthcare system in the US.
Support
This material is based upon work supported in part by the Department of Veteran Affairs, Veterans Health Administration, Office of Research and Development, and the Center for Innovations in Quality, Effectiveness and Safety (CIN 13-413). Dr. Nowakowski is also supported by a National Institutes of Health (NIH) Grant (R01NR018342).