Insomnia as a Mental Illness?

If you've dealt with insomnia for any length of time, you've probably noticed it affects more than your energy levels. Your mood shifts. Your patience wears thin. Anxiety creeps in. At some point, you might wonder: is this a sleep problem, a mental health problem, or both?

The relationship between insomnia and mental illness is complicated. They often show up together, and each one can make the other worse. Understanding how they connect is the first step toward addressing either one.

Is insomnia considered a mental disorder?

Technically, yes. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5), which clinicians use to diagnose psychiatric conditions, now classifies insomnia as a standalone disorder. To meet the criteria, sleep difficulties must cause significant distress or impairment in daily functioning, occur at least three nights per week, and persist for at least three months.

This was a shift from earlier editions, which treated insomnia primarily as a symptom of other conditions rather than a disorder in its own right. The change reflects growing recognition that chronic insomnia can exist independently and cause serious problems on its own.

That said, insomnia rarely exists in isolation. Research suggests that 40-50% of people with psychiatric disorders also experience insomnia, with rates reaching 50-80% among those actively seeking psychiatric treatment. 

The connection runs deep, and it goes both ways.

Also Read: Understanding Insomnia: Complete Guide to Better Sleep

How are insomnia and mental health connected?

Insomnia and mental health conditions have a bidirectional relationship. This means each one can cause or worsen the other.

Poor sleep affects how your brain regulates emotions, processes stress, and handles daily challenges. Over time, chronic sleep deprivation can increase your risk of developing anxiety, depression, or other mental health issues.

At the same time, mental health conditions often disrupt sleep directly. Racing thoughts from anxiety can keep you awake. Depression can cause early morning waking or excessive sleeping. PTSD can bring nightmares that fragment your sleep. The mental health condition drives the insomnia, which then makes the mental health condition harder to manage.

In some cases, both insomnia and a mental health condition stem from a shared underlying cause, like chronic stress, a medical condition, or a major life change. Untangling cause and effect isn't always straightforward, which is why treatment often needs to address both sleep and mental health together.

Insomnia and depression

Depression is one of the most common conditions that co-occurs with insomnia. Studies have found that over 90% of people with major depressive disorder report some form of sleep disturbance, whether that's difficulty falling asleep, waking up too early, or sleeping too much.

The relationship works in both directions. People with insomnia are significantly more likely to develop depression than those who sleep well. And depression itself disrupts the sleep cycles that help regulate mood, creating a feedback loop that's hard to break without intervention.

Treating one condition often helps the other. Research has shown that addressing insomnia directly, through approaches like cognitive behavioral therapy for insomnia (CBT-I), can improve depressive symptoms even when depression isn't the primary treatment target.

Also Read: New York Times Suggests Sticking Your Head in the Freezer to Help with Insomnia—Here’s a Better Solution

Insomnia and anxiety

Anxiety is the second most common mental health condition linked to insomnia. Estimates suggest that anywhere from 24% to 36% of people with chronic insomnia also meet criteria for an anxiety disorder.

The connection makes intuitive sense. Anxiety activates your body's stress response, raising cortisol levels and keeping your nervous system on alert. That state of heightened arousal makes it difficult to relax enough to fall asleep or stay asleep through the night.

Worry about sleep itself can also become a source of anxiety. If you've had enough bad nights, you might start dreading bedtime, which only makes the problem worse. This pattern, sometimes called conditioned insomnia, is common in people who've dealt with sleep problems for a long time.

Also Read: What Is Sleep Anxiety? Signs, Causes, and Natural Ways to Find Relief

Insomnia and other mental health conditions

The link between insomnia and mental health extends beyond depression and anxiety.

Post-traumatic stress disorder (PTSD): Sleep disturbance is a core feature of PTSD. Nightmares, hyperarousal, and difficulty feeling safe enough to sleep are common. Poor sleep can also interfere with the brain's ability to process traumatic memories, which may slow recovery.

Obsessive-compulsive disorder (OCD): A 2020 Swedish study found that people with OCD are seven times more likely to be diagnosed with insomnia or prescribed sleep medication compared to the general population.

Bipolar disorder: Sleep disruption often precedes mood episodes in people with bipolar disorder. Changes in sleep patterns can be an early signal that a manic or depressive episode is developing.

Schizophrenia: Research indicates that up to 80% of people with schizophrenia experience disturbed sleep. Sleep problems may worsen symptoms like cognitive difficulties and social withdrawal.

Substance use disorders: Insomnia is common during both active substance use and withdrawal. Alcohol, in particular, fragments sleep architecture even though it may initially seem to help with falling asleep.

Does treating insomnia help mental health?

Often, yes. Improving sleep can have a measurable effect on mental health symptoms, even when mental illness is the underlying driver.

CBT-I is the first-line treatment for chronic insomnia and has been shown to reduce symptoms of depression and anxiety alongside improving sleep. Unlike sleep medications, CBT-I addresses the patterns and behaviors that perpetuate insomnia rather than just sedating you through the night.

For people whose insomnia is driven by an underlying mental health condition, treating that condition is also important. Sometimes both need to be addressed simultaneously for either one to improve meaningfully.

Lifestyle factors matter too. Regular exercise, consistent sleep schedules, limiting caffeine and alcohol, and managing stress can all support both sleep and mental health.

When should you get help?

Everyone has occasional nights of poor sleep, especially during stressful periods. But if sleep problems persist for weeks or months, or if you're noticing changes in your mood, energy, or ability to function during the day, it's worth talking to a doctor or mental health professional.

Consider seeking help if you:

• Have trouble falling or staying asleep most nights for a month or longer

• Feel exhausted during the day despite spending enough time in bed

• Notice increased anxiety, irritability, or low mood

• Find that sleep problems are affecting your work, relationships, or quality of life

• Use alcohol, medications, or other substances to help you sleep

A healthcare provider can help determine whether your insomnia is a standalone issue, part of a mental health condition, or both. From there, they can help you develop a treatment plan that addresses the full picture.

The bottom line

Insomnia and mental health are deeply connected. Chronic insomnia is now recognized as a disorder in its own right, but it frequently overlaps with conditions like depression, anxiety, and PTSD. Each can trigger or worsen the other, which is why effective treatment often needs to address both.

If you're struggling with sleep and your mental health, you're not imagining the connection. Start with good sleep habits and stress management. If those aren't enough, talk to a professional. And if you're looking for a natural sleep aid, Sip2Sleep® offers a melatonin-free option with Montmorency tart cherry extract and Rafuma Leaf (Venetron®) to help promote better sleep quality and reduce anxiety. Sleep and mental health are intertwined, and improving one often helps the other.

References:

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