What Causes Insomnia?

Insomnia is trouble falling asleep, staying asleep or waking too early, even when you have time to sleep. It usually starts with a trigger, such as stress, illness or a new medicine. It becomes long-lasting when habits and worries that form around poor sleep keep it going after the trigger fades.

What counts as insomnia?

Many people sleep poorly now and then. Insomnia is a sleep problem that also affects your day, such as tiredness, low energy, poor focus or a short temper. About one-third of adults report at least one insomnia symptom, and about 6% meet the full criteria for an insomnia diagnosis.^[1]

Insomnia is its own condition, not just a sign of something else. It can happen alongside other health problems, and it often needs its own treatment.

Acute vs chronic insomnia

Sleep doctors use the International Classification of Sleep Disorders (ICSD-3) to sort insomnia by how long it lasts. The psychiatric manual, DSM-5, uses the same time frame.^[2]

• Acute (short-term) insomnia — lasts less than 3 months. It often follows a clear trigger, like a move, a loss, a deadline or an illness, and often gets better on its own.
• Chronic insomnia — trouble sleeping at least 3 nights a week for at least 3 months, with daytime effects.^[2]

The 3 P's: why insomnia starts and why it stays

Many sleep doctors explain insomnia with the "3P" model, first described by sleep researcher Arthur Spielman and colleagues.^[3] It sorts causes into three groups:

• Predisposing factors — things that make some people more likely to sleep poorly, such as a tendency to worry, a light-sleeping family, being female or getting older.
• Precipitating factors — the trigger that starts the problem, such as stress, grief, a new baby, pain, illness, travel or a new medicine.
• Perpetuating factors — what keeps insomnia going after the trigger is gone, such as spending long hours in bed awake, napping, sleeping in, using more caffeine and worrying about sleep.

This is why treating only the first trigger often does not fix chronic insomnia. The perpetuating habits need attention too.

Common causes and triggers

• Stress and life changes — work, school, money, family or health worries can keep the brain on alert at bedtime.
• Medical conditions — chronic pain, heartburn (GERD), asthma, thyroid problems, menopause symptoms and needing to urinate at night can all break up sleep.
• Medicines — steroids, some decongestants, some antidepressants, stimulants and some asthma and blood pressure medicines can affect sleep. Never stop a prescribed medicine on your own; ask your doctor about timing or other options.
• Caffeine, alcohol and nicotine — caffeine late in the day can delay sleep. Alcohol may make you drowsy at first but tends to cause waking later in the night. Nicotine is a stimulant.
• Other sleep disorders — sleep apnea can cause frequent waking, and restless legs syndrome can make it hard to settle down. Learn the signs of sleep apnea and about restless legs syndrome.
• Body clock problems — shift work, jet lag or a naturally late body clock can make it hard to sleep at the times you need to.
• Mental health — anxiety, depression and PTSD often disturb sleep.

Insomnia and mental health

Sleep and mood affect each other. Anxiety and depression can cause insomnia, and insomnia can also come first. In a review of long-term studies, people with insomnia who were not depressed had about twice the risk of developing depression later.^[4]

If you have low mood, lose interest in things you enjoy or have thoughts of harming yourself, tell a doctor right away. In a crisis, call or text 988, the Suicide and Crisis Lifeline.

Why insomnia keeps going

After weeks of poor sleep, the bed can start to feel like a place to worry instead of rest. People often try to make up for lost sleep in ways that make it worse:

• Going to bed early or staying in bed late — more time awake in bed teaches the brain that bed is for being awake.
• Napping or sleeping in — this lowers your drive to sleep the next night.
• Clock watching and worry — checking the time and fearing the next day keeps the body on alert.
• Relying on alcohol or sleep aids — these can cause lighter, broken sleep and may not help for long.

Cognitive behavioral therapy for insomnia (CBT-I) targets these habits and thoughts directly. Doctor groups recommend it as the first treatment for chronic insomnia in adults.^[5][6] Our in-depth guide to CBT-I explains how it works and what to expect.

When to see a sleep specialist

Talk with a doctor if:

• Poor sleep lasts more than a few weeks — especially if it is affecting work, school, mood or relationships.
• You feel drowsy while driving — or doze off during the day when you don't mean to.
• You snore loudly, gasp or stop breathing in sleep — these can be signs of sleep apnea.
• Your legs feel restless or uncomfortable at night — and moving them brings relief.
• You rely on sleeping pills, alcohol or other aids — most nights to fall asleep.

More signs are in when to see a sleep specialist.

Insomnia care in Cedar Park

Dr. Minal Patel is board-certified in pediatrics and sleep medicine. Our practice treats insomnia, including with CBT-I, and can test for other sleep disorders, such as sleep apnea and restless legs. Read more about our insomnia treatment. We are accepting new patients. Office hours are Monday through Friday, 8:30 to 5:00. We accept Medicaid and CHIP for sleep patients. We do not take walk-ins.