Sleep is closely connected to mental and emotional health and poor sleep has demonstrated links to depression, anxiety, bipolar disorder, and other conditions. Brain activity during sleep has profound effects on emotional and mental health. Sufficient sleep, especially REM sleep, facilitates the brain’s processing of emotional information. During sleep, the brain works to evaluate and remember thoughts and memories, and it appears that a lack of sleep is especially harmful to the consolidation of positive emotional content. This can influence mood and emotional reactivity and is tied to mental health disorders and their severity, including the risk of suicidal ideas or behaviours.

Research indicates that there is a bidirectional relationship between sleep and mental health in which sleeping problems may be both a cause and consequence of mental health problems.

• Around 75% of depressed people show symptoms of insomnia, and many people with depression also suffer from excessive daytime sleepiness and hyper-somnia.

• Sleep and depression may have a bidirectional relationship in which sleep problems and depressive symptoms are mutually reinforcing.

• Research suggests that for some people, improving sleep may help reducing the symptoms of depression.

• People with seasonal affective disorder tend to sleep too much or too little or experience changes to their sleep cycles.

• Anxiety disorders have a strong association with sleeping problems. Worry and fear contribute to a state of hyper-arousal in which the mind is racing, and hyper-arousal is considered to be a central contributor to insomnia. Sleep problems may become an added source of worry, creating anticipatory anxiety at bedtime that makes it harder to fall asleep.

• Research has found an especially strong connection between Post Traumatic Stress Disorder (PTSD) and sleep. At least 90% of U.S. veterans with combat-related PTSD from recent wars have insomnia symptoms.

• With bipolar disorder, sleep patterns change considerably depending on emotional state. During manic periods, reduced sleep is common, but during depressed periods, excessive sleep is common. Sleep disruptions often continue between episodes. There is evidence that sleeping problems induce or worsen manic and depressive periods and that, because of the bidirectional relationship between bipolar disorder and sleep, treatment for insomnia can reduce the impact of bipolar disorder.

• People with schizophrenia are more likely to experience insomnia and circadian rhythm disorders. Sleeping problems may be exacerbated by medications that are used to treat schizophrenia. Poor sleep and symptoms of schizophrenia may be mutually reinforcing, so there are potential benefits to stabilising and normalising sleep patterns.

• Sleeping problems including difficulty falling asleep, frequent awakenings, and excessive daytime sleepiness are common in people with Attention Deficit Hyperactivity Disorder (ADHD). There is evidence of a bidirectional relationship between sleep and ADHD. In addition to being a consequence of ADHD, sleep problems may aggravate symptoms like reduced attention span or behaviour problems.

• Children and adolescents with Autism Spectrum Disorder (ASD) have a higher prevalence of sleep problems including insomnia and sleep-disordered breathing.

Sources: The Sleep Foundation | Wikipedia | National Library of Medicine