Nocturnal Limb Movements Are Correlated with Cerebral White Matter Hyperintensities (P05.001)

Abstract

Objective: To explore the association of nocturnal limb movements (LMs) and sleep quality with cerebral white matter hyperintensities (WMH). Background Nocturnal LMs are associated with transient but significant increases in night-time blood pressure and autonomic hyperactivity; emerging evidence suggests a link with vascular disease. While obstructive sleep apnea is linked with WMH, the relationship between nocturnal LMs and WMH remains to be clarified. Design/Methods: Patients evaluated in a tertiary care behavioral neurology clinic were assessed with polysomnography for various sleep problems. Polysomnography was scored according to criteria from the American Academy of Sleep Medicine. WMH were rated using the Age Related White Matter Changes Score (ARWMC) from FLAIR MRI. Polysomnographic (transformed where necessary) and ARWMC data were compared using Pearson correlations. Results: Forty-five participants were assessed (69% male, mean age 64 years) and vascular risk factors were as follows: hypertension (27%), hyperlipidemia (18%) and diabetes (9%). Prior cerebrovascular disease (7%), obstructive sleep apnea (49%) and restless legs syndrome (33%) were also present. The mean ARWMC score was 3.84 (range 0-25, standard deviation 4.73). When controlling for hypertension, the total ARWMC score was correlated with total LMs per hour of sleep (r=0.66, p=0.01). There were no differences in the ARWMC score between hemispheres, but more LMs were noted on the left side (66.3 vs. 24.1, p Conclusions: LM counts strongly correlated with the presence of WMH. In addition, sleep efficiency was negatively correlated with WMH. In keeping with developing evidence, our findings suggest that nocturnal LMs associated with poor quality sleep may contribute to episodes of nocturnal hypertension, which have been implicated in the development of WMH, even after controlling for the presence of daytime hypertension. Supported by: Dr. Mark Boulos is supported by a Focus on Stroke Research Fellowship, which is funded by the Canadian Institutes of Health Research, the Heart and Stroke Foundation of Canada, and the Canadian Stroke Network. Disclosure: Dr. Boulos has nothing to disclose. Dr. Pettersen has nothing to disclose. Dr. Jewell has nothing to disclose. Dr. Black has received personal compensation for activities with Novartis Pharmaceuticals, Pfizer, GlaxoSmithKline, Roche Pharmaceuticals, and Bristol-Myers Squibb. Dr. Black has received research support from Novartis Pharmaceuticals, Pfizer, Roche, and GlaxoSmithKline. Dr. Murray has received personal compensation for activities with Pfizer and Valeant as a consultant.