The Impact of Sleep Quality on Symptoms, Cognition, and Functioning in SCI
While sleep disruption and disorders are common in individuals with spinal cord injury (SCI), little is known about how these disturbances impact symptoms (fatigue and pain), cognition (subjective and objective), and functioning (physical activity and social participation) in these individuals. Because sleep disturbance has been shown to be associated with poor functional outcomes (i.e., worse symptoms, poorer cognition, less physical activity, and reduced social participation) in other clinical populations such as multiple sclerosis, and these disturbances are readily treatable, there is a need to better understand these relationships in individuals with SCI. Therefore, we will use five innovative measurement strategies to examine the role of sleep in day-to-day symptoms, cognition, and functioning in individuals with SCI. First, we will continuously monitor autonomic nervous system activity including heart rate variability and galvanic skin response to provide objective and reliable assessments of sleep quality. Next, we will use ecological momentary assessment to provide repeated, real-time assessments of sleep, symptoms (pain and fatigue), and functioning (physical activity) in the natural environment; these measures are not subject to recall bias or memory decay. Third, daily diaries will provide repeated daily measures of symptoms (fatigue, pain, depression, and anxiety), subjective cognition, and functioning (social participation) using validated measures to provide a more in-depth daily assessment. Fourth, we will employ accelerometer technology to objectively measure physical activity without reliance on self-report. Finally, we will administer a standardized neuropsychological assessment to provide an evaluation of the components of cognition that are commonly affected by sleep disturbance (e.g., processing speed, working memory, learning, memory, and executive function). We will engage 175 individuals with SCI in this study. Over the course of seven days, we will continuously assess objective autonomic nervous system and physical activity, and will collect self-reported symptom (sleep, fatigue, and pain) at five intervals throughout each day. In addition, participants will complete an internet-based daily diary each evening that consists of brief questionnaires on symptoms (sleep, pain, fatigue, depression, anxiety, and cognition) and functional outcomes (social participation). We will also conduct a standardized neuropsychological exam at the end of the study that evaluates cognitive domains known to be impacted by poor sleep. The use of these multiple methods will increase measurement reliability and elucidate the role that sleep quality plays in day to day functioning. Ultimately, this work is designed to inform the development of more efficient, effective, and individualized interventions designed to improve sleep quality and overall health-related quality of life for those with SCI.