Diagnosing sleep disorders
Many factors can cause short-term sleep disturbances. This includes work stress, relationship problems, financial difficulties, and temporary health problems. These sleep problems usually resolve themselves when the reason for the anxiety or sleeplessness goes away.
A sleep disorder, however, disrupts your life – and not just for a few days. Sleep disorders are serious and can affect your cognitive and physical functioning. They also increase your chances of becoming obese, having a heart attack or stroke, or becoming diabetic.
The main symptoms of sleep disorders include difficulty falling and staying asleep, excessive tiredness during the day, and sleep disruptions.
Insomnia causes people to struggle with initiating or maintaining sleep. Excessive tiredness during the day could also point to a condition such as narcolepsy, and sleep disruptions could be caused by sleep apnoea, excessive snoring, night terrors, sleepwalking and the grinding of teeth (bruxism). It’s important for sleep disorders, which are neurological disorders, to be diagnosed and treated correctly.
Here are some ways in which doctors and sleep specialists diagnose sleep disorders:
Your doctor will ask you detailed questions about your medical history, any conditions you may have, and any medication you’re taking. You may also be asked about your lifestyle choices, as these could contribute to sleep difficulties.
Many conditions can affect your sleep: heartburn, diabetes, heart failure, arthritis, kidney disease, nocturia (the need to get up to urinate constantly during the night), thyroid disease, and breathing problems.
Some medications that could contribute to sleeping difficulties include diuretics, medication containing alcohol or caffeine, corticosteroids, beta blockers, antihistamines, and certain antidepressants, to name but a few.
Your doctor will try to establish if any of the above-mentioned factors are at play.
Your doctor might ask you to put together a sleep diary over a number of weeks. You may have to included information on how many hours you sleep each night, how long you take to fall asleep, how often you wake up and for how long, how rested you feel in the morning, and how sleepy you feel during the day.
You may have to ask you partner for some details, such as whether you snore or gasp during sleep, or whether you jerk your limbs.
Your doctor may suggest that you stay overnight in a sleep laboratory while a sleep specialist does a polysomnogram (PSG). Monitors and electrodes will be placed on your face, chest, limbs, scalp and finger.
While you’re sleeping, these different devices will measure the level of oxygen in your blood, how much air moves in and out of your lungs, your eye movements, brain activity, your heart rate, and your rhythm and muscle activity.
A variety of sleep disorders can be detected in a sleep laboratory. It isn’t a painful process, but it could be uncomfortable to try and sleep in a strange place while being observed.
Multiple sleep latency test (MSLT)
This test (also called a “nap study”) is often used to diagnose narcolepsy and is usually done after you’ve spent a night being evaluated in a sleep laboratory.
You’ll be asked to nap for 20 minutes, 4 or 5 times during the day. Monitoring devices on your scalp and face will be used to record how long it takes you to fall asleep, and when you reach the various stages of sleep, especially REM.
If you fall asleep very easily and reach a stage of deep sleep within minutes, you could be suffering from narcolepsy. Daytime sleepiness could also point to sleep apnoea.
Treating sleep disorders
Reviewed by Dr Irshaad Ebrahim, specialist neuropsychiatrist in sleep disorders at The London Sleep Centre and The Constantia Sleep Centre. FRCPsych. April 2018.