How Sleep Doctors Diagnose Sleep Disorders

Sleep doctors diagnose sleep disorders in a set order: a detailed sleep history, a sleep diary and short questionnaires, a physical exam, and then the test that fits the problem they suspect. Not everyone needs an overnight sleep study. Some disorders, such as insomnia and restless legs syndrome, are usually diagnosed from your history alone, while others, such as sleep apnea and narcolepsy, need testing to confirm them.

Step 1: Your sleep history

The visit starts with questions about your nights and your days. Your answers point the doctor toward the right group of sleep disorders before any test is ordered.

• Your schedule — when you go to bed, fall asleep, wake up and nap, on work days and days off.
• Your main symptoms — snoring, gasping, trouble falling or staying asleep, daytime sleepiness, leg discomfort, or unusual movements at night.
• What others notice — a bed partner or parent may have seen breathing pauses, kicking, or acting out dreams.
• Health and medicines — medical and mental health conditions, medicines, caffeine and alcohol can all affect sleep.

To get ready for this conversation, see what to expect at your first sleep clinic visit.

Step 2: Sleep diary and questionnaires

Memory is not always accurate about sleep, so your doctor may ask you to track it and to fill out a few short forms. Each one answers a different question.

• Sleep diary — a daily log of bedtime, wake time and naps, usually for about two weeks.^[1] It shows real patterns, not just your worst nights.
• Epworth Sleepiness Scale — asks how likely you are to doze off in eight everyday situations.^[2] It measures how sleepy you are, not why.
• STOP-BANG — eight yes-or-no items, such as snoring, tiredness, blood pressure and neck size, that estimate the risk of obstructive sleep apnea.^[3]
• Insomnia Severity Index (ISI) — seven questions on how much trouble you have sleeping and how much it affects your day.^[4]

These tools help sort and track symptoms. They do not make a diagnosis on their own. For example, sleep medicine guidelines say a questionnaire should not be used to diagnose sleep apnea without a sleep test.^[5]

Step 3: The physical exam

The exam looks for clues that support or rule out what the history suggests. A sleep doctor will often check your weight and blood pressure, measure your neck, and look in your nose and mouth at the size of the tonsils, tongue and airway. In children, large tonsils and adenoids are a common reason for snoring and breathing pauses. The doctor may also check the heart, lungs and nerves, depending on your symptoms.

Step 4: Choosing the right test

There is no single sleep test for every problem. Your sleep doctor matches the test to the disorder they suspect.

• Obstructive sleep apnea — a home sleep apnea test or an in-lab sleep study (polysomnography). An in-lab study is often chosen for children and for adults with heart, lung or nerve conditions.^[5] Compare them in in-lab vs. home sleep study.
• Narcolepsy and other causes of heavy daytime sleepiness — an overnight in-lab study followed the next day by a nap test called the MSLT. Learn more about the MSLT and MWT.
• Body clock (circadian rhythm) disorders — a sleep diary, often with actigraphy, a watch-like device worn for several days up to two weeks.^[6] See how actigraphy works.
• Insomnia — usually diagnosed from your history and sleep diary. A sleep study is not routinely needed unless another sleep disorder, such as sleep apnea, is suspected.^[1]
• Restless legs syndrome — diagnosed from your description of the symptoms. A blood test for iron levels, including ferritin, is recommended because low iron can make restless legs worse.^[7]
• Acting out dreams and other unusual night behaviors — an in-lab sleep study with video. Confirming REM sleep behavior disorder requires this type of study.

Step 5: Diagnosis and a treatment plan

A sleep medicine physician reviews the test results together with your history and exam. Test numbers alone do not tell the whole story. For sleep apnea, a key number is the apnea-hypopnea index (AHI), the number of breathing pauses and shallow breaths per hour of sleep.

Your doctor then explains the diagnosis and the treatment options that fit it. That might be CPAP for sleep apnea, cognitive behavioral therapy for insomnia (CBT-I), iron or other treatment for restless legs, or changes to light and sleep timing for a body clock disorder. Follow-up visits check that the plan is working and adjust it if needed.

When to see a sleep specialist

Talk with your doctor about a sleep evaluation if you or your child:

• Snore loudly — especially with gasping or pauses in breathing that others notice.
• Feel very sleepy in the day — even after a full night in bed, or doze off while driving.
• Struggle to sleep — trouble falling or staying asleep on most nights for weeks or months.
• Have an urge to move the legs — in the evening or at night, eased by moving.
• Act out dreams — or have other movements or behaviors in sleep that could cause injury.

More warning signs are covered in when to see a sleep specialist.

Getting evaluated in Cedar Park

At Teddy Bear Pediatrics & Sleep Medicine, Dr. Minal Patel is board-certified in both Pediatrics and Sleep Medicine and sees children and adults for sleep problems. Services include in-lab sleep studies, home sleep apnea tests, CPAP and BiPAP titration, narcolepsy testing with the MSLT, and care for restless legs and insomnia, including CBT-I. The office is open Monday to Friday, 8:30 AM to 5:00 PM, and is accepting new patients by appointment (no walk-ins). Medicaid and CHIP are accepted for sleep medicine patients.