Do you often fall asleep during the day? Let's learn about the MSLT test (Multiple Sleep Latency Test)

Do you also suddenly feel sleepy and close your eyes during the day, while working or talking? Even though you sleep well at night, do you feel extremely tired and sleepy during the day without any energy? If this excessive daytime sleepiness is interfering with your daily activities, today we are talking about a special test that can be done to find the cause.

What is MSLT?

Simply put, the `MSLT` (Multiple Sleep Latency Test) is a test that measures how long it takes you to fall asleep during the day. It also shows what sleep stages you go through during that short period of sleep. Doctors use this test to find the cause of your excessive daytime sleepiness and to diagnose sleep disorders related to it.

What kind of diseases does this test detect?

The `MSLT` test mainly helps to diagnose two medical conditions.

This test is done during the day, but it is always done after another overnight sleep study the previous night.

Who needs this MSLT test?

If you have a hard time staying awake during the day, your doctor may recommend this test. Imagine you're in an important meeting at the office, or driving a car. What can happen if you suddenly fall asleep at a time like this... If this sleepiness has been affecting your daily activities, work, and studies for months, it's important to get it checked out.

Usually, the doctor will first ask you a few questions, or have you fill out a short questionnaire like the Epworth sleepiness scale. This is to assess how much this sleepiness is affecting your daily life.

How is this test done?

The MSLT involves giving you five naps every two hours throughout the day. Each time you nap, you have small sensors attached to your body. These sensors monitor things like your brain activity and eye movements.

Doctors are mainly looking at two things here:

1. How early do you fall asleep?

2. Do you enter a special sleep stage called `REM` (Rapid Eye Movement) during that short nap?

How should you prepare before the test?

Your doctor will give you clear instructions on what to do before the test, which may include:

• Keep a sleep diary: Write down the time you go to bed and the time you wake up every day for about two weeks.
• Follow a specific sleep pattern: Try to go to bed and wake up at the same time every day for a few weeks before the test.
• Wearing an actigraph device: Your doctor may give you a small device, like a watch, that you wear on your wrist to measure your sleep and wake patterns.
• Changing Medications: You should inform your doctor about any medications you are currently taking. Some medications may affect the results of this test, so your doctor may need to temporarily stop or change them. Never stop taking any medications without your doctor's approval.

After a sleep study (polysomnography) the night before the MSLT test, you may also have a blood or urine sample (drug screening) taken in the morning to check for certain drugs or medications that can affect sleep.

What happens on the day of the test?

On the day of the test, something like this happens:

1. You will lie down on a bed and a technician will attach sensors to your skin.

2. After checking that they are working properly, he turns off the lights in the room and leaves.

3. You are advised to sleep.

4. You will be woken up after a set time (about 20 minutes).

5. Then you will be given a two-hour break. During this time, you can eat, drink (no caffeine - coffee, tea, chocolate, some soft drinks), look at your phone, or read a book. But you cannot sleep during this time. You must stay awake.

6. After two hours, give yourself another chance to sleep as described above.

This process is repeated 5 times throughout the day. If you have any questions, there is a microphone to talk to the technician outside the room.

What to do if you don't fall asleep during the MSLT?

This is a problem for many people. It's not easy to fall asleep in a new place with a lot of sensors on your body. This is normal. If you don't fall asleep within the allotted time (20 minutes), the technician will record it as "It took 20 minutes to fall asleep" and start your two-hour rest period. So don't worry about it.

You can also bring something from home, such as a pillow, bed sheet, or book, to help you sleep comfortably.

How to view test results?

After the test, your doctor will analyze your results, using things like your average time to fall asleep and the number of times you enter REM sleep.

It usually takes a healthy person about 11 minutes to fall asleep during the day. The doctor will not only look at these `MSLT` results, but also at your sleep diary, the report of the previous night's sleep test, and everything else to come to a final conclusion.

When should I see the doctor?

If you are experiencing excessive daytime sleepiness that is preventing you from functioning, don't ignore it. Be sure to talk to your doctor about it. He or she can perform the MSLT test or other tests to determine the exact cause and prescribe the appropriate treatment.

If the test results indicate that you have a medical condition, your doctor will advise you on the medications or lifestyle changes needed to manage those symptoms.

MSLT test, Multiple Sleep Latency Test, Daytime sleepiness, Excessive sleepiness, Narcolepsy, Hypersomnia, Sleep tests