A new study has shed light on the crucial link between sleep, circadian rhythms, and psychiatric disorders. The research suggests that disturbances in sleep and internal body clocks can trigger or worsen mental health issues. The study emphasizes the prevalence of sleep-circadian disturbances across all psychiatric disorders and highlights the need for holistic treatments that address these factors.
Sleep and circadian rhythm disturbances are commonly found in psychiatric disorders such as insomnia, bipolar disorder, and early psychosis. These disturbances have significant impacts on individuals’ mental health. The review explores various mechanisms that contribute to the link between sleep-circadian disturbances and psychiatric disorders, including genetic predispositions, exposure to light, and changes in neuroplasticity.
The review also highlights the potential of new therapeutic approaches to improve mental health outcomes. Treatments like light therapy and Cognitive Behavioral Therapy for Insomnia (CBT-I) have shown effectiveness in targeting sleep and circadian factors. These innovative treatments have the potential to alleviate symptoms of psychiatric conditions.
The study was conducted by an international team of researchers from the University of Southampton, Kings College London, Stanford University, and other institutions. The researchers focused on adolescents and young adults with psychiatric disorders, as this is a critical period when individuals are most at risk of developing mental health disorders.
Insomnia is more prevalent in people with mental health disorders compared to the general population. It affects individuals during remission, acute episodes, and especially in early psychosis. Additionally, a significant proportion of individuals with mood disorders experience both insomnia and hypersomnia, where they find it hard to sleep at night but are sleepier during the daytime. Similar proportions of people with psychosis also experience this combination of sleep disorders.
Circadian rhythm sleep-wake disorders (CRSWD) have been studied less extensively but show that a considerable number of patients with bipolar disorder experience delayed sleep-wake phase disorder. During manic episodes, body clock processes run seven hours ahead, while during the depressive phase, they run four to five hours behind. Successful treatment normalizes the timing.
The researchers examined various mechanisms that contribute to sleep-circadian disturbances in psychiatric disorders. During adolescence, physiological changes in sleep patterns combine with behavioral changes, such as staying up later and getting less sleep on school nights. This misalignment between the body clock and sleep-wake rhythms increases the risk of sleep disturbances and adverse mental health outcomes.
Genetic predisposition, exposure to light, neuroplasticity, and other factors also play a role in sleep-circadian disturbances. Those with a genetic predisposition towards a reduced change in activity levels between rest and wake phases are more likely to experience depression, mood instability, and neuroticism. Time spent outdoors has been associated with a lower probability of mood disorders. Sleep is also crucial for the brain’s formation of new neural connections and processing emotional memories.
The study also highlights new treatments that target sleep and circadian risk factors. Cognitive Behavioral Therapy for Insomnia (CBT-I) has been shown to reduce anxiety, depressive symptoms, and trauma symptoms in individuals with PTSD. Light therapy has proven effective in treating unipolar and bipolar depression, as well as perinatal depression. The timing of medication, meals, and exercise can also impact circadian phases.
The review suggests that by targeting sleep and circadian factors, new preventative measures and therapies can be developed. This includes population-level considerations such as adjusting school and work schedules or optimizing light exposure in the built environment. Personalized interventions tailored to individual circadian parameters are also promising.
Innovative multicomponent interventions, such as Transdiagnostic Intervention for Sleep and Circadian dysfunction (Trans-C), combine modules that address different aspects of sleep and circadian rhythms into a sleep health framework applicable to a range of mental health disorders.
Dr. Sarah L. Chellappa from the University of Southampton, senior author of the review, emphasizes the importance of understanding how sleep and circadian factors interact to develop interventions that benefit both sleep and mental health symptoms.
The research was funded by the Alexander Von Humboldt Foundation, and the findings will be published in the Proceedings of the National Academy of Sciences (PNAS). This study marks a significant step forward in understanding and treating psychiatric conditions by focusing on sleep and circadian science. The research incorporates insights from an international team of experts, highlighting the potential for improved understanding and treatment of psychiatric disorders.
