Mental Health Disorders and Insomnia

Insomnia is comorbid with mental health issues. This means that people often have both at the same time. Doctors think sleep issues can cause mental illness and vice versa. The relationship between the 2 is complex. Having problems with both your sleep and your mental health may affect your treatment plan.^1-4

What causes insomnia?

Hyperarousal is a feeling of being very anxious, distressed, or overly alert. A lot of people with insomnia describe feeling hyperaroused.⁵

It may be that when your nervous system is hyperaroused, that causes insomnia. A hyperaroused brain's daily sleep-wake cycle (also called circadian rhythm) is not normal. The brain spends too much time in the wake cycle.⁵

Hyperarousal can cause the brain to be overstimulated. This may impact sleep. It may also raise the risk for mental health issues caused by hyperarousal.⁵

Disruptions in the circadian rhythm and inflammation may cause insomnia. There are likely many causes.^6,7

Insomnia and mental health

Insomnia and mental health issues are often related conditions. When they are, both are harder to treat. Insomnia raises your risk for mental health issues. And mental health issues raise your risk for insomnia.^3,7,8

So which one causes the other? Experts think that the relationship between the 2 conditions may be more circular. This means they affect each other rather than one always causing the other.^2,7

A circular dynamic

Insomnia and mental health conditions feed off each other. Sometimes, changes in the brain that cause insomnia may raise the risk for mental illness. Other times, changes in the brain that cause mental illness may raise the risk for insomnia.^2,7

A better understanding of the causes of insomnia and mental health issues could explain why insomnia occurs both before a mental health issue and after it.^2,7

Here, we describe the links between mental health issues and insomnia and some possible causes for both.

Depression

A 2019 review showed that up to 90 percent of people with depression have sleep problems. Insomnia worsens depression. It raises the risk for depression to come back (relapse) and suicidal thinking. Doctors use poor sleep to predict when someone will have an episode of depression.²

The relationship between these conditions is complex. A 2018 review looked at people with both insomnia and depression. It found that:^2,7

• 41 percent had insomnia before the mood disorder
• 29 percent had the mood disorder before insomnia
• 29 percent started having symptoms for both at the same time

Schizophrenia and bipolar disorder

Insomnia happens during all phases of schizophrenic episodes. It even appears before the first episode. Doctors use insomnia to predict psychotic episodes. They also use it to identify people at risk for schizophrenia.^2,9

Bipolar disorder causes episodes of intense mood swings. Sleep problems worsen before an episode. They peak during an episode.^10-12

Anxiety disorders

Anxiety affects about 30 percent of adults. People with the following types of anxiety are likely to also have insomnia:^2,13

1. Generalized anxiety disorder
2. Panic disorder
3. Social anxiety
4. Fear of being away from home or in a space where you cannot get away (agoraphobia)

Attention deficit hyperactivity disorder (ADHD)

Trouble falling asleep in the first place occurs in some children with ADHD. This kind of sleep problem is called sleep-onset insomnia.²

Post-traumatic stress disorder (PTSD)

One study assessed the sleeping habits of military people before and after they were sent into service (deployed). Those with sleep disorders before they were deployed were more likely to get PTSD.⁴

What links these conditions?

The following causes may link depression and insomnia:⁷

• Inflammation in the cells
• Overly active immune system
• Abnormal circadian rhythm
• Genetics
• Abnormal chemical messengers (neurotransmitters) in the brain

An abnormal circadian rhythm may link insomnia and schizophrenia.²

Changes in the brain may be the link connecting many of these conditions. Yet, environmental factors also affect the likelihood of getting insomnia and mental disorders. This is why it is hard to determine what causes their relatedness.^2,14

Treating mental health and insomnia together

Doctors once thought that treating the mental disorder would cure sleep problems. But studies show that treating only depression and not insomnia leads to relapsing depression. Treatment works better if the mental health issue and insomnia are treated together.^2,3,7

The following treatments may help with insomnia:^4,7

• Cognitive behavioral therapy for insomnia (also called CBT-I)
• Bright light therapy
• Melatonin supplements

Some drugs that treat mental illness worsen sleep. If you have sleep and mental health issues, your doctor may switch your prescription or change your dosage.^4,7

Talk to your doctor before changing your treatment plan.