7.2 POOR SLEEP QUALITY RELATED TO WORSE VASCULAR FUNCTION IN INDIVIDUALS WITH MULTIPLE SCLEROSIS

Abstract

Background: Poor sleep quality has been related to poor vascular function and higher risk of cardiovascular disease in the general population. Persons with multiple sclerosis (MS) exhibit a high cardiovascular risk, and report poor sleep quality. To date, the association between sleep quality and vascular health in MS has not been investigated. Objective: To investigate differences in vascular health between good and poor quality sleepers with MS. Methods: After a 10 minute rest in the supine position, resting heart rate (HR) and brachial blood pressure (BP) were collected.Aortic SBP, augmentation index (AIX), HR normalized AIX (AIX@HR75), subendocardial viability ratio (SEVR), end systolic pressure (ESP), and central pulse wave velocity (PWVc) were measured with applanation tonometry in individuals with MS (n=49). Carotid intima-media thickness (IMT) and beta-stiffness were measured with carotid ultrasound, and peak forearm blood flow (FBF Peak) was measured with strain gauge plethysmography. Sleep quality was measured with the Pittsburgh Sleep Quality Index (>5 was categorized as poor sleep quality). Age was used as a covariate. Results: AIX@HR75 and SEVR were different between groups, even with age as a covariate, suggesting higher vascular risk for the poor quality sleepers with MS. Conclusions: This study shows that within the MS population, poor quality sleepers have a higher cardiovascular risk than good quality sleepers. Whether poor sleep raises their cardiovascular risk more than in the general population is an area of future investigation. Good quality sleepers with MS (n=23) Poor quality sleepers with MS (n=26) Effect of sleep quality Effect of age Mean (SD) Mean (SD) p Partial Eta2 p Partial Eta2 N Female (%) 18 (75%) 22 (82%) PSQI score 2.9 (1.5) 9.7 (3.1) Age 44 ±13 52 ±10 BMI 26.9 ±5.4 28.1± 5.6 .582 0.007 .584 0.007 HR 64 ±10 65± 8 .136 0.048 .014* 0.125 SBP 116 ±14 122 ±14 .384 0.017 .025* 0.105 DBP 72 ±9 74 ±10 .457 0.012 .559 0.007 MAP 86± 10 90 ±11 .403 0.015 .175 0.040 Aortic SBP 106 ±14 114 ±14 .223 0.032 .001** 0.200 AIX 21.1 ±13.7 30.0± 9.0 .082 0.064 <.001** 0.282 AIX@HR75 15.1± 12.0 25.5± 7.6 .007** 0.150 .001** 0.211 SEVR 158± 21 147 ±18 .026* 0.103 .160 0.042 ESP 96 ±12 103± 14 .213 0.034 .007** 0.148 PWVc 6.7± 1.4 7.5± 1.4 .200 0.036 .007** 0.146 PWVc/MAP 0.078± 0.014 0.084 ±0.016 .376 0.017 .063 0.073 IMT 0.51± 0.11 0.53 ±0.12 .571 0.007 <.001** 0.342 Beta 7.3 ±2.3 8.1± 2.7 .785 0.002 .002** 0.193 FBF Peak 17.8 4.4 17.2 6.6 .988 0.000 .185 0.038 *p<0.05 **p<0.01