Relationship Between Sleep, Body Clock and Mental Health

A fresh analysis of recent scientific findings suggests that sleep and internal body clock issues might cause or worsen a variety of mental health problems.

According to the review, published today in the Proceedings of the National Academy of Sciences, gaining better knowledge of the relationship between sleep, circadian rhythms, and mental health could lead to the development of novel holistic treatments for mental health issues.

“Sleep-circadian disturbances are the rule, rather than the exception, across every category of psychiatric disorders,” said Dr. Sarah L. Chellappa from the University of Southampton, senior author of the review. “Sleep disturbances, such as insomnia, are well understood in the development and maintenance of psychiatric disorders, but our understanding of circadian disturbances lags behind.

“It is important to understand how these factors interact so we can develop and apply sleep-circadian interventions that benefit the sleep and mental health symptoms of patients.”

An international team of researchers from the University of Southampton, Kings College London, Stanford University, and other institutions investigated new information on sleep and circadian aspects, with an emphasis on adolescents and young adults with psychiatric conditions. This is the time when people are most likely to acquire mental health illnesses, as well as disruptions in sleep and circadian cycles.

Insomnia is more common in people with mental health disorders than in the general population, particularly during remission, acute episodes, and early psychosis, where more than half of people have difficulties sleeping and staying asleep. Around a quarter to a third of people with mood disorders suffer from both insomnia and hypersomnia, which occurs when patients have difficulty sleeping at night but are more sleepy during the day. A similar proportion of patients with psychosis suffer from this mix of sleep difficulties.

Meanwhile, the few studies on circadian rhythm sleep-wake disorders (CRSWD) indicate that 32% of bipolar disorder patients sleep and wake later than typical (a condition known as Delayed Sleep-Wake Phase Disorder). Body clock processes (such as endogenous cortisol rhythms) have been shown to be seven hours ahead during manic episodes and four to five hours behind during depressive periods. After a successful therapy, timing returns to normal.

What are the mechanisms?

The researchers investigated the potential processes underlying sleep-circadian abnormalities in psychiatric illnesses. During adolescence, physiological changes in our sleep patterns combine with behavioral changes, such as staying up later, receiving less sleep on school nights, and sleeping in on weekends.

Dr. Nicholas Meyer of King’s College London, who co-led the review, stated, “This variability in the duration and timing of sleep can lead to a misalignment between our body clock and our sleep-wake rhythms, which increases the risk of sleep disturbances and negative mental health outcomes.”

Researchers also investigated the role of genes, exposure to light, neuroplasticity, and other potential factors. Those with a genetic propensity for a slower transition in activity levels between rest and wake phases are more likely to develop sadness, mood instability, and neuroticism.

According to population-level studies, self-reported time spent outside is associated with a lower risk of mood disorders. Sleep is thought to have an important role in how the brain makes new neural connections and processes emotional memories.

New treatments

Dr. Renske Lok, of Stanford University, who co-led the review, stated, “Targeting sleep and circadian risk factors presents the opportunity to develop new preventative measures and therapies. Some of these are population-level considerations, such as the timing of school and work days, or changes in the built environment to optimize light exposure. Others are personalized interventions tailored to individual circadian parameters.”

Cognitive Behavioral Therapy for Insomnia (CBT-I) has been found to alleviate anxiety, depression, and trauma symptoms in patients with PTSD.

In unipolar and bipolar depression, light treatment (given in the morning) proved more helpful than a placebo. Combining it with medication proved to be more beneficial than taking medication alone. Other research suggests that light is useful in alleviating prenatal depression.

The timing of medication, meals, and exercise may also have an affect on circadian phases. Taking melatonin in the evening can help people with delayed sleep-wake phase disorder adjust their body clock forward, allowing them to sleep more normally, and it may also benefit people with concomitant psychiatric problems.

Nightshift employment can have a negative impact on mental health, but eating during the day rather than at night may assist, as research has shown that daytime eating avoids mood impairment.

The review also highlights novel multicomponent therapies, such as Transdiagnostic Intervention for Sleep and Circadian Dysfunction (Trans-C). This combines modules that treat various components of sleep and circadian rhythms to create a sleep health framework that may be applied to a variety of mental health conditions.

Dr. Chellappa added, “Collectively, research into mental health is poised to take advantage of extraordinary advances in sleep and circadian science and translate these into improved understanding and treatment of psychiatric disorders.”

Source Link