Carol Everson, PhD

Specialties

• Sleep physiology
• Health consequences of chronic sleep restriction

Carol Everson is Professor of Medicine in the Division of Endocrinology and Molecular Medicine and holds a secondary appointment in the Department of Cell Biology, Neurobiology & Anatomy. She earned her PhD at the University of Chicago in the Division of Social Sciences. Her research provided new insight into the physiological consequences of severe sleep deprivation. She next completed a staff fellowship and senior staff fellowship at the National Institutes of Health in Bethesda, Maryland, where she established a basic science sleep research laboratory and conducted studies on the effects of sleep deprivation on cerebral metabolism, nutritional demands, and host defenses. Post fellowship, she joined the Department of Physiology in the University of Tennessee College of Medicine as an assistant professor. There she advanced her discoveries of sleep deprivation on the interplay between immune-related changes, endocrine abnormalities, and poor control over gut bacteria. Dr. Everson joined MCW as an associate professor in 2000 and was awarded the rank of professor in 2007. At MCW, she has demonstrated that chronic sleep restriction results in increased cell injury and metabolic consequences that accumulate, eventually resulting in observable pathology, not all of which is reversible. Her research provides inroads into the pathophysiology of long-term sleep restriction and its medical implications. Dr. Everson has served on numerous scientific peer review panels at local and national levels and as a charter member of the NIH study section, Neural Basis of Psychopathology, Addictions and Sleep Disorders. She is a member of MCW’s Neuroscience Research Center and Cardiovascular Center. She is a long-standing member of both the American Academy of Sleep Medicine and the Sleep Research Society. She previously served on the Board of Directors of the Sleep Research Society and as Board Liaison to the Research Committee of the Sleep Research Society Foundation.

Sleep as a basic biological requirement for health and life. Sleep is on par with other basic biological requirements, such as food and water, for which there are no known substitutes. While total deprivation of basic biological requirements can produce death, chronic deficiencies produce disease. Many years of chronic deficiency of a basic biological requirement may be required for morbidity to become sufficiently severe to be recognized as “disease.” Because basic biological requirements, such as sleep, are involved in nearly every physiological function, significant deficiencies result in several categories of disease. Sleep disturbances are major risk factors for cancer, cardiovascular disease, cerebrovascular disease, lung disease, osteoporosis, and autoimmune diseases, among others. Our laboratory is working to elucidate neural, immune, and hormonal mechanisms altered by chronically insufficient sleep that may lead directly to impaired health or secondarily to exacerbation of other diseases.

Sleep is restorative. A corresponding focus of the laboratory is to address the question, “What does sleep do at a cellular and systems level?” It is well accepted that sleep is “restorative.” However, what, specifically and biologically, is restored, and how might those processes be enhanced in circumstances where sleep is chronically deficient? Our laboratory has provided evidence that the properties of sleep after chronic sleep deprivation include restoration of a balance between DNA damage and repair, decreased turnover of intestinal epithelium, and decreased metabolic and inflammatory burdens. These properties appear to be biological mechanisms and functions that contribute to the restorative value of sleep.

Research initiatives include follow-up of our findings of chronic sleep restriction effects:

• Blood and bone marrow abnormalities point to inflammatory processes
• Bone remodeling abnormalities are consequential for healthy aging
• Oxidative damage to DNA poses a cancer risk
• Changed nutritional demands and increased workload of visceral organs indicate a high metabolic cost of postponed sleep functions
• Hormone imbalances contribute to health impairment by insidious means
• Uncoordinated body functions due to circadian rhythm misalignment may be synergistic with chronic sleep deficiency in producing pathology