A sleep study (called a polysomnogram or PSG for short) is a comprehensive diagnostic test that records your physical state during various stages of sleep and wakefulness. By monitoring key physiological parameters such as brain activity (EEG), eye movements (EOG), muscle activity (EMG), heart rate (ECG), breathing patterns, blood oxygen levels (SpO2), and body movements, a sleep study provides a detailed understanding of how your body functions during sleep. This information is crucial for identifying disruptions that may indicate a physical sleep disorder.
A sleep study is commonly recommended for individuals experiencing symptoms that interfere with their ability to achieve restful and restorative sleep. The following symptoms often point to underlying sleep disorders, and a PSG is the gold standard for diagnosing them. By addressing these issues, individuals can significantly improve their overall quality of life, as proper sleep is essential for physical and mental health.
Sleep Study
A sleep study is commonly performed to investigate the following symptoms:
Poor Sleep Quality
Many people wake up feeling as though they haven’t slept at all, even after a full night in bed. This could be due to interruptions in deep or REM sleep, which are critical for restorative rest. Conditions like sleep apnea or periodic limb movement disorder often disrupt these stages, leaving individuals feeling drained despite spending hours asleep.
Poor Sleep Quality
Sleep quality goes beyond the number of hours slept. Fragmented sleep, frequent awakenings, or difficulty reaching deeper stages of sleep can result in poor sleep quality. PSG can identify patterns such as micro-arousals caused by breathing issues or involuntary muscle movements.
Daytime Sleepiness or Fatigue
Excessive daytime sleepiness can interfere with daily life, making it difficult to stay awake, focus, or perform tasks. This may result from conditions like narcolepsy, sleep apnea, or insufficient restorative sleep. A sleep study pinpoints the cause of these issues.
Breathing Disruption Episodes During Sleep
Episodes of stopped or shallow breathing during sleep, known as apneas or hypopneas, are hallmark signs of sleep apnea. These disruptions can lead to oxygen deprivation, strain on the cardiovascular system, and poor sleep quality. PSG monitors your breathing and oxygen levels to confirm the presence of sleep-disordered breathing.
Waking Up at Night to Use the Bathroom (Nocturia)
Frequent night time urination may disrupt sleep and result from conditions like sleep apnea, restless legs syndrome, or other nocturnal issues. A PSG can reveal whether nocturia is related to interruptions in your sleep cycle.
Difficulty with Concentration and Memory
Poor sleep can impair cognitive functions such as focus, problem-solving, and memory retention. Sleep disorders like insomnia, apnea, or fragmented sleep patterns may contribute to these issues. PSG provides insight into whether sleep quality is affecting brain function.
Morning Headaches
Waking up with headaches is often linked to poor sleep, sleep apnea, or teeth grinding (bruxism). Oxygen deprivation or strain from disrupted breathing may be responsible. PSG helps diagnose these underlying causes by tracking oxygen saturation and breathing irregularities.
Snoring
Snoring is not just a nuisance; it can be a sign of obstructed airways during sleep. Persistent and loud snoring is often associated with obstructive sleep apnea, a condition that affects breathing and overall health. A sleep study can determine whether snoring is benign or indicative of a more serious issue.
Waking Up with a Dry Mouth
Dry mouth upon waking often indicates mouth breathing, which is commonly associated with sleep apnea. A sleep study can uncover patterns of disrupted breathing or snoring that contribute to this symptom.
Insomnia and Unexplained Awakenings
Insomnia can manifest as difficulty falling asleep, staying asleep, or waking up too early. PSG evaluates whether physical factors like restless legs syndrome, apnea, or other disturbances are contributing to sleeplessness.
Leg Jerks / Restless Legs at Night
Involuntary leg movements during sleep, known as periodic limb movements (PLMs), can disrupt sleep continuity. Restless legs syndrome (RLS) often coincides with PLMs, making sleep uncomfortable. A sleep study monitors leg muscle activity to diagnose these conditions.
Abnormal Behaviors at Night (e.g., Sleepwalking)
Parasomnias, such as sleepwalking, night terrors, or REM sleep behavior disorder (acting out dreams), can be distressing for both individuals and their families. PSG captures brain and muscle activity to identify the triggers for these unusual behaviors.