Assessing and diagnosing sleep disorders

Sleep problems and disorders can affect every part of daily life. It is important for a clinician to undertake a thorough assessment in order to understand what might be causing or contributing to a sleep disorder. The results of testing can help confirm (or exclude) a diagnosis, and inform treatment planning. There are many different types of assessment and diagnostic tools and ways to assess a patient’s sleep and circadian health concerns.

The process may include conversations, questionnaires, sleep diaries, wearable tracking devices, or special lab studies completed overnight or during the day. This page explains why different sleep assessment tools are used, what each type measures, and what to expect before, during, and after assessment.

The pathway to sleep disorder diagnosis is different for everyone, but the first step is to make an appointment with a medical professional.

• Talk to a doctor. Visit a primary care physician or sleep specialist to discuss symptoms and next steps. The clinician will take a detailed history and perform a physical exam.
• Screening and Information Gathering. The physician may have a person complete questionnaires, keep a sleep diary, or wear a health-monitoring device to collect data.
• Diagnostic Testings. The clinician will provide a referral for any necessary diagnostic testing, including various types of sleep studies or laboratory assessments. 

These screening and information gathering tools can help differentiate among sleep disorders and determine the need for further testing. 

Visit a primary care physician or sleep specialist to discuss symptoms and next steps. A clinician will review symptoms, sleep timing, daytime function, medical and mental health history, medications, substances, work or school schedules, and family observations. A physical examination may look for airway, neurologic, cardiovascular, or other relevant findings, because sometimes health conditions can cause sleep disorders. The opposite is also true – some sleep disorders can influence health outcomes. A physician will ask questions to join these dots and bridge the gap between day and night.

Because many sleep disorders have overlapping symptoms, it can help to bring along prepared information on:

• Symptoms a person is experiencing, including both nighttime and daytime effects
• Symptom onset (when it first happened), frequency (how often it happens), timing (when it happens), duration (how long the symptom lasts), and severity (how bad it is)
• Other diagnosed medical conditions and medications
• A person’s use of caffeine, alcohol, nicotine, marajuana, or other substances
• Any family history of sleep disorders or other medical conditions
• Any data available from wearable devices such as a smart watch or sleep ring

In addition to taking a history and performing a physical exam, the clinician may ask a person to 

complete validated sleep questionnaires during the visit. A validated questionnaire is a survey that has been tested by scientists to prove that it accurately measures a condition. These questionnaires can screen to see if further testing is warranted, and help measure symptom severity.

There are many validated questionnaires used to screen for sleep disorders.  A few of the most common are:

• Epworth Sleepiness Scale (ESS) — measures excessive daytime sleepiness
• Insomnia Severity Index (ISI) — measures insomnia severity
• STOP-Bang — measures risk-factors for obstructive sleep apnea
• Pittsburgh Sleep Quality Index (PSQI) — measures broad sleep quality
• BEARS — broad pediatric screening measuring Bedtime problems, Excessive daytime sleepiness, Awakenings, sleep Regularity and duration, and Snoring 
• Pediatric Sleep Questionnaire—Sleep-Related Breathing Disorder (PSQ-SRBD) — measures pediatric sleep-disordered breathing
• Morningness–Eveningness Questionnaire (MEQ) — measures circadian timing and chronotype
• REM Sleep Behavior Disorder Screening Questionnaire (RBDSQ) — suspected REM sleep behavior disorder

A sleep diary is a record kept over one or more weeks that shows the timing and duration of sleep, nighttime symptoms, awakenings, naps, and daytime symptoms. It is intended to track day to day variations in symptoms and establish a pattern that can be evaluated against the patterns of various sleep disorders. The clinician will often provide a worksheet or template to record the information.

Actigraphy refers to gathering biometric data from a wrist-worn clinical device similar to a smart watch. The device records rest and activity patterns over days or weeks to build a picture of a person’s lifestyle and sleep patterns. It can capture the amount of sleep, time to fall asleep, time spent in bed, and sleep efficiency of a person. Actigraphy can be useful for monitoring circadian rhythm concerns, insomnia evaluation, hypersomnolence disorders, and insufficient sleep syndrome.

Based on what the medical history, physical exam, questionnaires, actigraphy, and/or sleep diary show, the physician will recommend tests that can help provide a diagnosis. In some cases, a sleep disorder is diagnosed by ruling out other possible causes of a person’s symptoms. 

An overnight sleep study, also called polysomnography, is performed at a sleep center. During the study a person is connected to several different types of leads that record biometric data. The various instruments record brain activity, sleep phases, eye movements, muscle activity, heart rhythm, airflow, breathing effort, blood oxygen saturation, carbon dioxide expiration, and other signals. It can help identify sleep apnea, movement disorders, unusual behaviors, and sleep-stage patterns.

Selected adults with suspected obstructive sleep apnea may be able to use a simplified sleep apnea test at home, instead of having to go to a sleep center for a full sleep study. Eligibility is usually determined by a physician’s evaluation and insurance requirements. A home sleep apnea test measures airflow, breathing effort, blood oxygen saturation, heart rate, and sometimes body position or snoring. 

A home sleep apnea test can only test for sleep apnea, and does not evaluate other sleep disorders. Sometimes this test will need to be followed up with a sleep study at a sleep center. Other times it will be followed by a titration study, which is used to determine appropriate air pressure for a PAP device (commonly known as CPAP).

The multiple sleep latency test (MSLT) is generally used when narcolepsy or idiopathic hypersomnia is suspected. The test measures how quickly someone falls asleep during scheduled daytime naps, and whether rapid eye movement sleep appears unusually early. It is usually conducted the day after a sleep study is performed.

Depending on the suspected sleep disorder, a clinician may request blood tests, carbon dioxide monitoring, heart or lung testing, imaging, genetic testing, or referral to another specialist. Results from all screenings and diagnostic tests should be interpreted together with a person’s individual symptoms and goals. 

If there is concern about sleep or circadian health, or something is impacting overall health and quality of life – seeking help should be a priority. A person does not need to know the cause of problems before making an appointment with a clinician.

A two-way conversation with a health practitioner is an essential part of getting a clear diagnosis and treatment plan. Asking questions, setting goals, and committing to taking responsibility for things that can be managed are all part of a holistic approach to sleep and circadian health for both patient and clinician. Clear and effective communication between both parties helps achieve the best outcomes. 

If you are concerned about your sleep or circadian health – then take action and get help.

To learn more about diagnostic assessment for specific sleep problems and disorders, view our sleep problems & disorders page.