Association of cognitive impairment in Multiple Sclerosis with polysomnographic measurement of sleep disorders (P1.416)

Objective: To investigate the association between cognitive impairment (CI) and sleep disorders (SDs) in a multiple sclerosis (MS) cohort who report fatigue. Background: CI is common in MS, with significant impact on quality of life measures. SDs are also common, and contribute to MS-related fatigue which occurs at a similar prevalence to CI in MS (40–70%). An association of CI with SDs could offer novel therapeutic strategies for CI in MS. Design/Methods: In a cross-sectional observational study, cognitive assessment with the Brief International Cognitive Assessment in MS (consisting of the Symbol Digit Modality test[SDMT], California Verbal Learning test[CVLT-2] and Brief Visuospatial Memory test[BVMT-R]), and 3-second Paced Auditory Serial Addition test (PASAT-3), was performed on the day of polysomnography. Results: 15 participants were recruited from MS clinic. Participants were 73% female, 87% with relapsing-remitting MS. Mean age was 43(range 25–59), and median expanded disability status scale 1.5(range 0–4.5). Average body mass index was 27.1(range 20.5–32.3). 4 participants (27%) had CI. 10 (67%) had abnormal polysomnography, 4 with more than one SD recorded. Mild or moderate obstructive sleep apnoea was observed in 6 (40%) of patients, mild periodic limb movement disorder (PLMD) in 5, and severe PLMD in 2 patients. All patients with a normal sleep-study were cognitively preserved. All those with CI had a SD, however an abnormal sleep study was not significantly associated with CI, likely due to very low levels of CI observed in this small group. SDMT negatively correlated with PLMD (Pearson’s R −0.522, p=0.04), and PASAT-3 with both total sleep time (R −0.6, p=0.02) and sleep efficiency (R=−0.79, p Conclusions: Significant relationships were observed between some sleep parameters and cognitive domains. A normal sleep study was highly predictive of cognitive preservation in this cohort. Disclosure: Dr. McNicholas has nothing to disclose. Dr. Russell has nothing to disclose. Dr. Nolan has nothing to disclose. Dr. Tubridy has nothing to disclose. Dr. Hutchinson has nothing to disclose. Dr. Garvey has nothing to disclose. Dr. McGuigan has nothing to disclose.