UCLA

STUDY OBJECTIVES: Multiple sclerosis (MS) is an autoimmune disease impacting the central nervous system. A hallmark symptom of MS is fatigue, which impairs daytime function and quality of life (QOL). Sleep disorders and disturbances are common in persons with MS and exacerbate fatigue. We evaluated relationships between sleep-disordered breathing (SDB), insomnia symptoms, sleep quality, and daytime functioning in veterans with MS participating in a larger study. METHODS: Twenty-five veterans with clinically diagnosed MS were included (average age = 57 ± 11, 80% male). One had a co-occurring thoracic spinal cord injury. Twenty-four participants completed in-laboratory polysomnography (PSG) to measure apnea-hypopnea index (AHI) and sleep efficiency (PSG-SE). Insomnia Severity Index (ISI) and Pittsburg Sleep Quality Index (PSQI) were used to measure sleep subjectively. The Flinders Fatigue Scale (FFS), Epworth Sleepiness Scale (ESS), PHQ-9 depression scale, and GAD-7 anxiety scale assessed daytime symptoms. The World Health Organization Quality of Life (WHOQOL) was used to assess quality of life. Relationships between sleep (AHI, PSG-SE, ISI, PSQI), daytime symptoms (ESS, FFS, PHQ-9, and GAD-7), and quality of life (WHOQOL) were evaluated with bivariate correlations. RESULTS: Higher ISI (r = 0.78, 95% CI = [0.54, 0.90], p < .001), higher PSQI (r = 0.51, 95% CI = [0.10, 0.77], p = .017), and lower PSG-SE (r = -0.45, 95% CI = [-0.74, -0.02], p = .041) were associated with worse fatigue (FFS). Higher ISI was also associated with worse WHOQOL (Physical Domain; r = -0.64, 95% CI = [-0.82, -0.32], p = .001). There were no other significant relationships. CONCLUSION: In veterans with MS, more severe insomnia and worse sleep quality may be associated with more fatigue and lower quality of life. Recognition and management of insomnia should be considered in future studies of sleep in MS.