Helen J. Burgess, PhD, discusses the results of a recent study with MedicalResearch.com that showed a home kit can assess a patient’s dim light melatonin onset.
Medical Research: What is the background for this study? What are the main findings?
Dr. Burgess: The 24 hour circadian clock in the brain has a profound influence on mental and physical health. Circadian rhythm sleep disorders occur when the internal circadian clock’s timing is out of synch with the external social world, which often dictates when we should eat, work and sleep. One such disorder, delayed sleep phase disorder, occurs when the circadian clock runs too late relative to social time.
Patients with delayed sleep phase disorder can appear to simply have insomnia, but careful measurement of their circadian timing can reveal the underlying circadian cause. Also, the treatment of delayed sleep phase disorder with either bright light and/or melatonin can be optimized by knowing a patient’s circadian timing, because the effect of these treatments can vary widely depending on when they are administered.
A problem in the sleep and circadian field is that the gold standard marker of circadian timing in humans, the dim light melatonin onset (DLMO), is typically only measured in the clinic or laboratory. Many clinics do not even measure the DLMO. Our group recently developed a home saliva collection kit to assist people in measuring their DLMO at home. Previously, we found the home DLMOs compared very well to laboratory DLMOs in healthy controls. In this paper, we extended this work to show the kit also works well in patients with delayed sleep phase disorder.