The Association between Symptoms of Autoimmune Diseases and Circadian Clock Disruption: A Pilot Study Using Only Healthy Controls

Abstract

Autoimmune disease occurs when the immune system attacks self-molecules. It ranges from organ-specific to systemic, including Rheumatoid Arthritis (RA), Multiple Sclerosis (MS), and Sjogren’s Syndrome (SS). Evidence indicates disturbances of the circadian clock to demonstrate detrimental effects on immunity, which may enhance susceptibility to autoimmune diseases. Moreover, prevalent symptoms experienced by RA, MS, SS patients include persistent pain and complaints of sleep and fatigue. Collectively, this thesis aims to validate emerging tools measuring circadian clock disruption as a means of early diagnosis and an accurate prediction of autoimmune disease trigger and progression. Validated surveys for disease-specific, symptomologies, circadian clock, chronotype and actigraphy were utilized to measure direct correlations. MS cognitive dysfunction was correlated with fatigue and sleep (r = 0.95, 0.93, 0.92). SS dryness was also correlated with fatigue and sleep (r = 0.89, 0.77, 0.82). SS fatigue had correlations with sleep (r = 0.90 and 0.72). However, no correlation was observed between SS dryness levels and amount of saliva collected (r = - 0.08). Sleep insomnia scores had correlations with fatigue and sleep (r = 0.95, 0.89, 0.87). Actigraphy-derived sleep minutes was correlated with each of the symptoms (r = - 0.87, - 0.81, - 0.87, - 0.81), while activity mean had a correlation with fatigue and pain (r = 0.90 and 0.95). Midpoint of sleep on free days measured by the Munich Chronotype Questionnaire (MCTQ) and actigraphy were not statistically different (t = - 0.95, p > 0.05). Evening chronotypes had a correlation with fatigue and sleep (r = - 0.92 and - 0.94), and morning chronotypes exhibited a correlation with pain (r = 0.96). Lastly, Morningness-Eveningness Questionnaire (MEQ) scores correlated well with the MCTQ midpoint on workdays (r = - 0.84). These findings demonstrate that the circadian clock and sleep is inextricably linked to autoimmune diseases, especially the exacerbation of symptoms. However, additional research is needed to establish pharmacological interventions that can improve the quality of life (QoL) of patients with severe autoimmune disease symptoms and reduce the effects of circadian clock disruption.