Clocks, Sleep and Mental Illness: Time to think again – Professor Russell Foster, CBE
Severe sleep and circadian rhythm disruption (SCRD) is a common feature of mental illness, yet its origins remain a mystery, its detection is frequently overlooked, and it is rarely treated. However the health consequences of SCRD are profound. SCRD promotes multiple illnesses ranging across abnormal metabolism; heart disease; reduced immunity; increased stress; and abnormal cognition and mood states. Significantly, these poor health states are common in psychiatric illness, yet SCRD is rarely identified as a cause or contributor of this poor health. So what are the possible mechanistic links between SCRD and mental illness?
We now appreciate that sleep and circadian timing systems are the product of a complex interaction between multiple brain regions and most brain neurotransmitter systems. Similarly, psychiatric illness arises from abnormalities in interacting brain circuits and neurotransmitter systems, many of which will overlap with those regulating sleep and circadian rhythms. In addition, SCRD itself will impact upon multiple aspects of brain function, including activation of the stress axis, which could further exacerbate mental health problems. In turn, medication, substance abuse, social isolation and/or activation of the stress axis associated with psychiatric illness will certainly impinge upon the sleep and circadian systems. In this presentation, these links will be considered along with how we might be able to use this new information for the development of new therapeutics for mental illness.