Daytime Sleep Studies: Are They Effective?

Sleep studies are typically conducted overnight to monitor brain and body activity while the patient sleeps. However, sleep studies can also be performed during the day to gain insight into a person's daytime sleepiness and diagnose sleep disorders such as narcolepsy. Daytime sleep studies are usually preceded by an overnight sleep study and involve similar sensors attached to the scalp and face to monitor brain activity, eye movement, heart rate, and breathing patterns. Two common tests conducted during daytime sleep studies are the Multiple Sleep Latency Test (MSLT) and the Maintenance of Wakefulness Test (MWT).

Daytime sleep studies are preceded by overnight sleep studies

Sleep studies are typically performed overnight, with the patient staying in a hospital sleep laboratory, an outpatient sleep clinic, or a standalone sleep lab or sleep centre. However, daytime sleep studies are also sometimes conducted, and these are usually preceded by an overnight sleep study.

An overnight sleep study involves the patient being hooked up to several types of monitors that track their brain and body activity while they sleep. Electrodes are attached to the patient's body to monitor their brain waves, eye movements, breathing, movement, heart rate, blood oxygen levels, and body positioning. The data from the sleep study is then evaluated by a doctor, who will discuss the results with the patient.

Daytime sleep studies are helpful in gaining insight into a person's daytime sleepiness. They use many of the same sensors as a nighttime study, except those used to monitor breathing. There are two types of tests conducted during the day: the Multiple Sleep Latency Test (MSLT) and the Maintenance of Wakefulness Test (MWT).

The MSLT is the most common way to objectively quantify sleepiness and is a key test in diagnosing narcolepsy. It involves 4-5 trials or "naps" spaced throughout the day, during which the patient is asked to relax and try to fall asleep. The MWT, on the other hand, measures the patient's ability to stay awake for a defined period under sleep-inducing circumstances.

Daytime sleep studies use sensors on the scalp and face to monitor sleepiness

Sleep studies are typically performed overnight, but they can also be done during the day. Daytime sleep studies are often preceded by an overnight sleep study and are used to gain insight into a person's daytime sleepiness.

Daytime sleep studies use many of the same sensors as nighttime studies, including sensors on the scalp and face. These sensors are used to monitor brain activity, eye movements, heart rate, and breathing patterns. The data collected during a daytime sleep study can help diagnose sleep disorders such as sleep apnea, restless leg syndrome, and narcolepsy.

One type of daytime sleep study is the Multiple Sleep Latency Test (MSLT), which is used to objectively quantify sleepiness and is a key test in diagnosing narcolepsy. The MSLT consists of 4-5 trials or "naps" spaced throughout the day, during which the individual is asked to relax and try to fall asleep. The data collected during an MSLT includes the mean sleep latency (the average time it took the person to fall asleep) and the number of REM periods.

Another type of daytime sleep study is the Maintenance of Wakefulness Test (MWT), which measures an individual's ability to stay awake for a defined period under sleep-inducing circumstances. This test is often used for individuals who work in professions that require sustained alertness, such as truck drivers or airline pilots.

Multiple Sleep Latency Tests (MSLT) are used to diagnose narcolepsy

Sleep studies are often carried out during the day to monitor a person's daytime sleepiness and are usually preceded by an overnight sleep study. Multiple Sleep Latency Tests (MSLT) are used to diagnose narcolepsy and are a key test for doing so. The MSLT measures excessive daytime sleepiness by evaluating how quickly a person falls asleep during the day in a quiet environment. This is done through a series of four to five scheduled naps, with each nap trial beginning two hours after the start of the previous one. The test is conducted in a dark and quiet room, with sensors placed on the patient's head, face and chin to measure whether they are asleep and to determine their sleep stage.

The MSLT is used to diagnose narcolepsy and hypersomnia, two sleep disorders characterised by excessive daytime sleepiness and sometimes oversleeping. Excessive daytime sleepiness is defined as feeling sleepy when you should be awake and alert. A sleep doctor may recommend an MSLT if they suspect you have excessive daytime sleepiness related to narcolepsy or a hypersomnia.

The MSLT is a full-day test that usually follows a sleep study that measures sleep quality and duration. The test measures how long it takes for a patient to fall asleep and how quickly they reach REM sleep. A positive MSLT is obtained when the patient falls asleep with a mean sleep latency of below eight minutes in the naps, and had at least two naps where REM sleep was reached. Narcolepsy is indicated when two or more REM sleep stages are recorded during the MSLT.

The MSLT is a useful test to objectively quantify sleepiness and is often used to diagnose narcolepsy.

Maintenance of Wakefulness Tests (MWT) measure the ability to stay awake

The Maintenance of Wakefulness Test (MWT) is a test that measures an individual's ability to stay awake during the day. It is a daytime test that is often conducted after an overnight sleep study. The MWT is designed to evaluate a person's alertness and wakefulness during their normal waking hours, rather than monitoring their sleep at night.

The MWT is typically administered within one-and-a-half to three hours after a person wakes up from their main sleep period. It involves four separate trials, during which the individual is monitored to assess their ability to stay awake. The test is conducted in a quiet, dark room, free from external factors that might influence the individual's ability to fall asleep, such as temperature or noise.

During each trial, the participant is asked to remain still and try to stay awake for as long as possible, usually for a maximum duration of 40 minutes. They are instructed to look straight ahead and are not allowed to engage in activities that might help them stay awake, such as singing or fidgeting. Electrodes are attached to their scalp to measure electrical activity in the brain and determine whether they are asleep or awake.

The MWT is particularly useful for individuals with certain sleep disorders, such as narcolepsy and obstructive sleep apnea. It helps sleep specialists understand the severity of their symptoms and evaluate the effectiveness of their treatment. Additionally, the MWT can be used to assess an individual's ability to perform certain occupations or activities safely, such as driving or operating public transportation.

To prepare for the MWT, individuals are advised to maintain adequate sleep habits and share information about their sleep patterns, medications, and caffeine consumption with their sleep specialist. It is important to follow the sleep specialist's instructions regarding sleep, medication, and caffeine consumption in the weeks leading up to the test.

Sleep studies can be performed at home or in specialised centres

Sleep studies are tests used to help diagnose sleep disorders such as sleep apnea, restless legs syndrome, insomnia, narcolepsy, and circadian rhythm disorders. They monitor brain and body activity while the patient sleeps. Sleep studies can be performed in specialised centres or at home, depending on the situation.

Specialised sleep centres are often set up in hospitals, clinics, or even hotels. They are designed to be as comfortable and homey as possible, with regular bedroom furniture, a television, and a private bathroom. The staff at these centres are trained in sleep medicine and may also practice related disciplines such as neurology, psychiatry, and pulmonary medicine.

When a patient visits a sleep centre for a sleep study, they are assigned a private room. Before bedtime, a technologist attaches sensors to the patient's head and body to record various data points, including brainwaves, eye movements, muscle activity, respiratory effort, airflow, blood oxygen levels, body positioning, snoring, and heart rate. The technologist monitors the patient throughout the night and assists with any issues. The study ends when the patient wakes up in the morning and has the sensors removed.

Home sleep studies, on the other hand, are typically used only for evaluating obstructive sleep apnea (OSA). They are more convenient and affordable than in-lab studies and allow patients to sleep in the comfort of their own beds. Home sleep studies use a device provided by the doctor, which the patient sets up at home following provided instructions. The device collects data on the patient's breathing, oxygen levels, and breathing effort throughout the night. However, home sleep studies are less effective at detecting OSA than in-lab polysomnography, and they do not capture as many signals.

The choice between an in-lab or at-home sleep study depends on the patient's situation and the specific sleep disorder being evaluated. For example, patients with certain heart, breathing, or neuromuscular problems may be better suited to an overnight sleep study at a specialised centre.

Frequently asked questions