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Sleep Study Test

Understanding Your Sleep: A Simple Guide to the Sleep Study Test

Sleep Study (Polysomnography)

A sleep study, formally known as a polysomnogram, serves as a pivotal diagnostic tool for healthcare providers to gain insights into various physiological aspects during sleep study test . By employing a range of sensors, this non-invasive test records data on critical body systems, offering a comprehensive perspective on the quality of an individual’s sleep.

Conditions that a sleep study can diagnose include:

  • Sleep apnea (obstructive and central).
  • Narcolepsy.
  • Periodic limb movement disorder (including restless legs syndrome).
  • Insomnia.
  • Certain types of seizures and epilepsy.
  • Night terrors (also known as sleep terrors).
  • Nocturnal panic attacks.
  • Sleepwalking or other sleep behavior-related disorders.
  • Sleep paralysis.
  • Other types of parasomnias and disruptive sleep disorders.

Purpose and Diagnostic Scope:

Healthcare providers recommend a sleep study when individuals present symptoms indicative of sleep-related conditions affecting neurological, respiratory, and cardiovascular functions.

Conditions diagnosed through this method encompass a broad spectrum, including sleep apnea, narcolepsy, periodic limb movement disorder, insomnia, seizures, night terrors, sleepwalking, and other disruptive sleep disorders.

Components of a Sleep Study Test :

The complexity of sleep necessitates a multifaceted approach, involving various sensors and monitoring methods:

Electroencephalography (EEG): Detects and records brain wave activity during different sleep stages.

Electrocardiography (EKG or ECG): Monitors heart activity, identifying rhythm irregularities.

Electromyogram (EMG): Tracks muscle movement, contributing to the analysis of sleep-related behaviors.

Electro-oculography (EOG): Measures eye movement, aiding in identifying different sleep phases.

Breathing Sensors and Respiratory Inductive Plethysmography (RIP) Belt: Monitor air movement and chest/belly expansion during breathing cycles.

Pulse Oximeter: Measures pulse and blood oxygen levels.

Video and Audio Monitoring: Offers visual and auditory cues for additional context during the sleep study.

Sleep study test

At-Home Sleep Study Test:

Distinguished from a full polysomnogram, at-home sleep study test is a focused evaluation, often employed when sleep apnea is strongly suspected or for post-treatment assessments. It involves fewer sensors, focusing primarily on breathing patterns.

Test Preparation and Day of the Study:

Preparation for a sleep study involves adhering to guidelines such as bathing before the test, avoiding certain skincare products, and packing essentials for an overnight stay. On the day of the study, individuals are encouraged to maintain their regular routines and abstain from caffeine and alcohol to ensure the most natural sleep patterns.

During the Sleep Study:

Upon arrival at the sleep lab, individuals transition into sleepwear, and sensors are strategically attached. Calibration tasks ensure the accurate functioning of sensors, and individuals may be asked to perform simple movements to assess sensor responsiveness.

Throughout the night, sleep lab personnel closely monitor the study, intervening if necessary, such as in the case of sensor displacement or signs of potential medical emergencies.

Post-Study Procedures:

After a night of monitoring, the morning involves the removal of sensors, and individuals can change into their regular clothes. While minimal side effects like skin irritation are possible, a healthcare provider interprets the gathered data.

Within a few days, individuals receive a follow-up call to discuss the results, receive a diagnosis, and explore potential treatment options. This comprehensive approach ensures a thorough understanding of sleep-related conditions and facilitates appropriate medical interventions.

sleep apnea test

What Type Of Sleep Apnea Test Is Right For You?

Dr. JC Suri talks about, Complete awareness on what type of Sleep Test is better for you?

A common disorder called sleep apnea makes it such that you shortly stop breathing while you sleep. Long-term, it may have serious health consequences if untreated.

You will probably go through an overnight sleep apnea test that tracks your breathing if your doctor suspects that you may have sleep apnea.

Typically, sleep studies are conducted between the hours of 10 p.m. and 6 a.m. If you’re a morning or evening person, this time period might not be ideal for you. Instead, a home test can be suggested.

You’ll spend the night in a separate room, equipped in a manner reminiscent of a hotel room with your comfort in mind. Bring your usual nighttime items, such as pajamas.

Sleep Apnea Test is used for?

To identify sleep disorders, a sleep test is used. Typical sleep problems include:

Sleep apnea is a medical disease that causes brief breathing pauses while you’re asleep. Throughout a single night of sleep, you can experience multiple recurring instances of breathing disruptions. As many as 30 episodes can be there per hour.

You may have trouble falling asleep and/or staying asleep all through the night if you have insomnia.

Restless leg syndrome makes your legs feel uncomfortable and causes a strong need to move them when you’re trying to fall asleep.

An illness of the nervous system called narcolepsy. It causes tiredness during the day. Additionally, you can suddenly find yourself napping all day.

Studies on sleep are non-invasive. The donation of a blood sample is not required. But your body will be fitted with a number of wires. This makes it possible for the sleep specialist to keep an eye on your breathing, mental activity, and other vital indications while you’re sleeping.

The more at ease you are, the more accurately the technician can monitor your sleep.

After you nod off, the technician will keep an eye on the following:

  • Your brain waves and eye movements, which reveal your sleep pattern
  • Your blood pressure and heart rate
  • Your breathing, including snoring, breathing pauses, and oxygen levels
  • Your posture and any motions of your limbs
  • For sleep research, there are two formats: whole night and split night.

If you take part in a full-night sleep study, your sleep will be monitored all through the night. If sleep apnea is diagnosed, you might need to return to the lab later to set up a breathing machine.

The first half of the night is utilized to track your sleep during a split-night research. In the event that sleep apnea is identified, the treatment device is set up during the second half of the night.

Pros and cons of in-lab sleep study: 

In-lab sleep tests have advantages and disadvantages. Talk to your doctor about your test and preference.


Best test currently in use- The most accurate method of diagnosing sleep apnea is an in-lab sleep test.

Possibility of studying two nights in a row- Split-night studies, as opposed to full-night and at-home tests, enable diagnosis and treatment in a single night.

Best test for a particular kind of work- To achieve an accurate diagnosis, people who pose a major risk to themselves or others if they fall asleep at work should take part in an in-lab sleep study. This includes pilots, police officers, and anyone who drive for taxis, buses, or ride-sharing services.

Best choice for those who suffer from various issues or sleep disorders. People with additional medical issues, such as sleep difficulties and heart and lung ailments, are more suited for in-lab monitoring.


Costlier than an at-home test- Although not all insurance companies cover this test, if you have insurance, your insurer might pay all or part of the expense. Before you may take an in-lab exam, some providers demand the results of an at-home test..

Less accessible. In-lab research necessitates travel to and from a sleep lab. This can take a long time or cost a lot depending on where you reside.

Longer wait times. You could have to wait several weeks or even months to take the test, depending on where you reside and the demand for this kind of test.

Less convenient. It’s more likely that taking an in-lab sleep test will interfere with your everyday activities and obligations or interfere with your work schedule.

Set sleep study hours. Between the hours of 10 p.m. and 6 a.m., many sleep studies are conducted. An at-home test might be preferable if you have a diverse sleep schedule.

At-home sleep test 

The motions, posture, and sleep cycles that are monitored during an in-lab exam are not monitored during an at-home test.

You can go to bed at your usual time the night of the test. To ensure that you correctly connect the monitoring sensors, pay close attention to the kit’s instructions.

Most in-home sleep apnea monitors are straightforward to set up. Typically, they consist of the following elements:

  • A finger clip that gauges your heart rate and blood oxygen levels.
  • A nasal cannula to gauge airflow and oxygen levels.
  • Sensors that monitor your chest’s rise and fall.
  • An at-home test does not track your movements, position, or sleep cycles the way an in-lab test does.

Your doctor will receive the test findings after you complete it. If therapy is required, they will get in touch with you to discuss the findings and decide on it.

Pros and Cons of a sleep test at home

Sleep tests performed at home offer benefits and drawbacks. You should discuss your preferred test with your doctor.


More convenient-  Home testing is more practical than laboratory tests. You can continue with your regular bedtime routine, which may give a more accurate indication of how you breathe while you sleep than in-lab testing.

Less costly- The cost of testing taken at home is about lower.

More accessible- For those who reside a great distance from a sleep centre, at-home tests might be a more practical choice. The monitor can even be mailed to you if necessary.

Faster results-  As soon as you receive the portable breathing monitor, you can start the test. Compared to a lab test, this might yield quicker results.


Less accurate- Test errors are more likely to occur in the absence of a technician. All cases of sleep apnea cannot be reliably detected by at-home tests. If you have a high-risk profession or another medical condition, this could be dangerous.

May lead to an in-lab sleep study-  Regardless of the outcome of your test, your doctor can still advise an in-lab sleep test. Additionally, you might still need to spend the night in the lab to have a treatment device fitted if you are diagnosed with sleep apnea.

Doesn’t test for other sleep problems-  Only breathing, heart rate, and oxygen levels are assessed during at-home examinations. This test is unable to identify narcolepsy or other prevalent sleep disorders.

Test results

The outcomes of your in-lab or at-home sleep apnea test will be interpreted by a physician or sleep specialist.

The Apnea Hypopnea Index (AHI) is a scale that physicians use to identify sleep apnea. This scale contains a calculation of the number of apneas, or breath pauses, per hour of study-related sleep.

Less than five apneas per hour are typical in those without sleep apnea or with a moderate version of the condition. More than 30 sleep apneas per hour are possible in those with severe sleep apnea.

When determining whether you have sleep apnea, doctors also check your oxygen levels. Although there isn’t a set threshold for sleep apnea, if your blood oxygen levels are lower than normal, it could be an indication.

Your doctor might advise repeating the test if the results are uncertain. Your doctor might suggest an additional test if sleep apnea is not identified but your symptoms persist.


Treatment options

Your level of sleep apnea will determine your course of treatment. Sometimes all that is needed is a change in lifestyle. These may consist of:

  • Losing weight
  • Using a specific pillow for sleep apnea
  • Changing the location of your bed

Continuous positive airway pressure (CPAP)-  There are numerous efficient medical sleep apnea therapy alternatives. Among them are: Constant positive airway pressure (CPAP). The CPAP machine is the most widely used and efficient treatment for sleep apnea. With this tool, your airways are inflated with the aid of a little mask.

Oral devices- Your throat may not close when you breathe if you have a dental appliance that moves your lower jaw forward. In cases of mild to moderate sleep apnea, these may be helpful.

Nasal device-  Some people with mild to severe sleep apnea have been demonstrated to benefit from Provent Sleep Apnea Therapy, a tiny bandage-like device. It is positioned right inside the nostrils and exerts pressure to maintain your airways’ openness.

Oxygen delivery-  To raise blood oxygen levels, oxygen may occasionally be provided in addition to a CPAP machine.

Surgery- When conventional therapies fail to work, surgery may be a possibility to change the way your airways are built. There are numerous surgical procedures available to treat sleep apnea.

Vital functions, such as breathing patterns, pulse rate, and oxygen levels, are measured during both in-lab and at-home sleep apnea examinations. Your doctor can diagnose sleep apnea for you using the results of these tests.

The most precise test to identify sleep apnea is a polysomnography (PSG) performed in a lab. The accuracy of tests for sleep apnea done at home is adequate. Additionally, they are more practical and economical.


Note: Do not consider JC SURI Blogs as medical advice. Never delay or disregard seeking professional medical advice from your doctor or other qualified healthcare providers because of something you have read on JC Suri.

You should always speak with your doctor before you start, stop, or change any prescribed part of your care plan or treatment. If you think you may have a medical emergency, call your doctor immediately.


Comprehensive Sleep Study Test Insights for Better Rest

Sleep Study (Polysomnogram)

Seep Apnea Tests and Diagnosis

Sleep Study (Polysomnogram), also termed a sleep study, is a thorough examination performed to diagnose sleep disorders. Your blood oxygen levels, pulse rate, breathing rate, and brain waves are all monitored during a polysomnography test.

A sleep center or a hospital sleep disorder unit may perform polysomnography. In order to accommodate shift workers who generally sleep during the day, polysomnography is occasionally performed during the day.

Your doctor might request that you undergo a polysomnogram, or sleep apnea test if you exhibit sleep apnea symptoms (PSG). This could be carried out at home or in a facility for sleep disorders.

A polysomnogram, often known as a sleep study, is a multi-part examination that electronically transmits and records particular physical activities you engage in while you're sleeping. An experienced sleep specialist reviews the recordings to determine whether you have sleep apnea or another sort of sleep problem.

If the test reveals sleep apnea, other sleep tests may be required to determine the best course of action.

Polysomnography may be used to start or modify your treatment plan if you've already been diagnosed with a sleep problem, in addition to aiding in the diagnosis of sleep disorders.

You might occasionally be able to complete the sleep study at home. Obstructive sleep apnea is the main type of sleep apnea that is diagnosed by a minimum number of sensors used in home sleep testing (OSA).

What to Expect During a Sleep Study (Polysomnogram)

If you should continue taking your drugs or stop them altogether before the test, your doctor will advise you. On the day of the test, avoid caffeine and alcohol because they may affect the results. Bring cozy pajamas, a book or magazine, and, if you have a specific pillow, it.

If you're undergoing a sleep center lab, you'll be given a private sleep center or hospital room for the night of your sleep study. There will be a central monitoring station nearby where medical professionals may keep an eye on patients while they are sleeping.

You'll have access to a private restroom; just let the technicians know when you'll be using it so they can disconnect the wires that are connecting you to the monitoring system.

You'll be hooked to equipment that could seem uncomfortable. However, most people have minimal trouble falling asleep.

For home testing, there is also more portable equipment available, particularly for simpler cases or circumstances.

Equipment Frequently Used for a Sleep Study

Surface electrodes will be applied to your face and scalp during a sleep study to transmit recorded electrical signals to the measuring devices. These signals, which are produced by the activity of your muscles and brain, are digitally captured. Your breathing is measured by belts around your chest and abdomen.

Your finger is attached to an oximeter probe that gauges the amount of oxygen in your blood.

Why it's done

In order to determine if, when, and why your sleep patterns are disrupted, polysomnography tracks the stages and cycles of your sleep.

Home sleep apnea testing equipment comes in a variety of designs and configurations. They often keep track of your heart rate, oxygen saturation, breathing rate, and airflow. One technique additionally includes data on blood vessel tone.

Non-rapid eye movement (NREM) sleep is the first stage of the typical sleeping process. Your brain waves significantly slow down during this phase, as shown by electroencephalography (EEG).

In contrast to later stages of sleep, your eyes don't move back and forth rapidly during NREM. After an hour or two of NREM sleep, your brain activity picks up again, and rapid eye movement (REM) sleep begins. Most dreaming occurs during REM sleep.

You normally go through multiple sleep cycles a night, cycling between NREM and REM sleep in about 90 minutes. Sleep disorders can disturb this sleep process.

Your doctor may recommend polysomnography if he or she suspects you have:

Sleep apnea or another sleep-related breathing disorder: In this condition, your breathing repeatedly stops and starts during sleep.

Periodic limb movement disorder: In this sleep disorder, you involuntarily flex and extend your legs while sleeping. This condition is sometimes associated with restless legs syndrome.

Narcolepsy: You experience overwhelming daytime drowsiness and sudden attacks of sleep in this condition.
REM sleep behavior disorder. This sleep disorder involves acting out dreams as you sleep.

Unusual behaviors during sleep: Your doctor may perform this test if you do unusual activities during sleep, such as walking, moving around a lot, or rhythmic movements.

Unexplained chronic insomnia: If you consistently have trouble falling asleep or staying asleep, your doctor may recommend polysomnography.


Polysomnography is a noninvasive, painless test. The most common side effect is a skin irritation caused by the adhesive used to attach test sensors to your skin.

How you prepare

Before polysomnography, you can be instructed to abstain from alcoholic beverages and caffeinated foods during the afternoon and evening. Both caffeine and alcohol can alter your sleep patterns and may exacerbate the signs of some sleep problems.

It is not advised to take a nap in the afternoon before a sleep study. Before your sleep study, you could be requested to take a shower or a bath. However, avoid using any lotions, gels, colognes, or makeup prior to the test because these can prevent the electrodes from working properly.

You can either pick up the equipment at your doctor's office or have it brought to you for a home sleep apnea test. You'll receive instructions outlining how to operate the tools.

Do you find yourself waking up tired, or maybe with a headache or dry mouth? Obstructive sleep apnea could be to blame. This happens when your breathing is interrupted during sleep, often for more than ten seconds.

The Facts About At-home Sleep Tests

They monitor breathing, not actual sleep.

A sleep test measures respiratory characteristics rather than the actual sleep in order to assess a patient for sleep apnea. The duration of your light or deep sleep, for example, won't be measured during the sleep test.

Instead, it will gauge how long it takes you to breathe, how hard you have to work to breathe, and whether your breathing is shallow or deep.

Sleep Study (Polysomnogram)

Your doctor needs to prescribe it:

This isn’t an over-the-counter test. Your primary care physician or a physician at a sleep clinic can order it for you to use at home.

It uses sensors to detect breathing patterns:

One of the sensors has a tiny probe that you wear over your finger to assess oxygen levels. Another mask with tubes will be placed over your ears and placed in your nostrils; it will resemble an oxygen mask.

To measure the rise and fall of your chest and belly while you breathe, additional sensors are attached to them.

It’s a small commitment:

Most at-home sleep tests are used just for one night. It’s also less expensive than a sleep study conducted in a clinic ― anywhere from a third to a fifth of the cost of doing an in-lab study and often covered by insurance.

It’s convenient:

With an at-home study, you’ll be in the comfort of your surroundings, which can mean a more accurate reading of how you sleep.

It doesn’t completely rule out apnea:

Your results will be submitted to your doctor after a sleep technologist has examined them after the test. If your symptoms don't go away, your doctor can suggest an in-lab experiment.

Home tests can occasionally be wrong because, for example, your sensors might stop working in the middle of the night. In a lab, a doctor is present to keep an eye on you.

You might have other sleep issues:

Breathing issues are not a sign of all sleep disorders. You might not have apnea if your symptoms continue to exist. Movement disorders that cause nocturnal restlessness and narcolepsy, a neurological illness that interferes with the body's sleep-wake cycles and results in excessive sleepiness, are two more prevalent sleep problems that do not impact the airways.

Together, you and your doctor can determine the cause.

Other Tests for Sleep Apnea

  • EEG (electroencephalogram) to measure and record brain wave activity
  • EMG (electromyogram) to record muscle activity such as face twitches, teeth grinding, and leg movements, and to look for REM stage sleep. During REM sleep, intense dreams often happen as the brain has heightened activity.
  • EOG (electrooculogram) to record eye movements. These movements are important in determining the different sleep stages, particularly REM stage sleep.
  • EKG (electrocardiogram) to record heart rate and rhythm
  • Nasal airflow sensor to record airflow
  • Snore microphone to record snoring activity

After a Sleep Study

In the morning, the technicians take off the sensors attached to your skin, and you go back to your everyday activities.
It takes the sleep specialist some time to review the study's hundreds of pages of data. They’ll send the results to your doctor. Once your doctor reviews them, you’ll meet to talk about the findings and next steps.

Sleep Study Results

  • The data will include information about your sleep, such as:
  • How long do you spend in each sleep stage
  • How often do you wake up
  • Whether you stop breathing or have trouble breathing
  • Whether you snore
  • Body position
  • Limb movements
  • Unusual brain activity patterns

Note: Do not consider JC SURI Blogs as medical advice. Never delay or disregard seeking professional medical advice from your doctor or other qualified healthcare providers because of something you have read on JC Suri. You should always speak with your doctor before you start, stop, or change any prescribed part of your care plan or treatment. If you think you may have a medical emergency, call your doctor immediately.