Janet M. Mullington, Sabra M. Abbott, Judith E. Carroll, Christopher J. Davis, Derk-Jan Dijk, David F. Dinges, Philip R. Gehrman, Geoffrey S. Ginsburg, David Gozal, Monika Haack, Diane C. Lim, Madalina Macrea, Allan I. Pack, David T. Plante, Jennifer A. Teske, Phyllis C. Zee

The impact of advances in sleep and circadian sciences over the last 20 years on medicine, health, and public safety has been limited in part by the lack of availability of objective tools capable of quantifying sleep and circadian function in point-of-care settings. This whitepaper is a product of a workshop that was designed to bring together thought-leaders in biomarker development, experts in sleep circadian biology and sleep disorders to identify barriers and opportunities informing the future development of point-of-care diagnostic tools. The workshop entitled, "Developing Biomarker Arrays Predicting Sleep and Circadian-Coupled Risks to Health," was held in Bethesda April 27-28 2015, and was jointly sponsored by the National Heart Lung and Blood Institute, National Institute on Aging and the Sleep Research Society (hereafter referred to as the biomarker workshop, http://www.nhlbi.nih.gov/research/reports). The Sleep Research Society supported a number of early career investigators to attend the workshop. They contributed to the writing of this whitepaper. A biomarker is a "biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, condition or disease."1,2 For the purpose of this whitepaper, "biomarkers" include quantifiable molecules and chemical properties of easily accessible biological samples (e.g., blood, urine, saliva). An ultimate goal is the development of robust and practical approaches for point-of-contact/care (p-o-c) implementation in population-based research and most importantly, for clinical applications to enhance sleep and circadian health. Biomarkers to assess current alertness status, sleep health and circadian function are lacking for: research, p-o-c diagnosis of sleep and circadian disorders, for prognosis and to evaluate the risk of associated heart, lung, blood, and aging diseases and disorders, and to assess the adequacy of therapy. The ideal biomarker would show high specificity (correctly identify the absence of a sleep deficiency) and sensitivity (correctly identify the state and degree of sleep loss, and possibly even duration that such a status has been ongoing). However, currently the field is without any viable biomarkers based in easily accessible bio-specimens. The availability of objective platforms capable of quantifying sleep and circadian function will ultimately determine whether advances in understanding sleep and circadian biology can be applied to improve health and disease management and reduce risks to health and public safety. In parallel with the development of p-o-c biomarkers, there is urgent need to enhance and validate mobile and wearable technologies that can be used in population phenotyping to accurately track sleep and circadian physiology and behavior. Together these efforts will position the field for participation in the Million Vet Program (http://www.research.va.gov/MVP/) and the Precision Medicine Initiatives (http://www.nih.gov/precision-medicine-initiative-cohort-program). With diagnostic tools for p-o-c measurement of sleep and circadian function, medical care and physician practices addressing sleep and circadian disorders and risk for metabolic and other diseases, will be vastly improved, translating into lower health care costs and a healthier population.