🌙 When Sleep Disorders Masquerade as Mental Health Conditions

Idiopathic Hypersomnia vs. Narcolepsy and Why They’re Often Misunderstood

As psychiatrists, we often meet patients who describe persistent fatigue, poor concentration, low mood, or emotional instability. It’s natural to think of depression, anxiety, or even ADHD, but sometimes, the real issue is happening while they sleep.

Two sleep disorders that frequently overlap with psychiatric presentations are Idiopathic Hypersomnia (IH) and Narcolepsy. Both cause excessive daytime sleepiness, yet they differ in key ways, and both are often misdiagnosed as mental health conditions.

💤 What Is Idiopathic Hypersomnia?

Idiopathic Hypersomnia (IH) is characterized by chronic, overwhelming daytime sleepiness despite getting adequate (or even excessive) nighttime sleep.

Key features:

• Long, unrefreshing sleep periods (often >10 hours)

• Difficulty waking up (“sleep drunkenness”)

• Foggy thinking or “brain fog”

• No cataplexy (sudden loss of muscle tone)

Because patients with IH appear tired, unmotivated, or cognitively slowed, they’re sometimes misdiagnosed with major depressive disorder or bipolar II disorder, especially when mood symptoms stem from sleep deprivation rather than primary psychiatric illness.

😴 What Is Narcolepsy?

Narcolepsy, on the other hand, involves instability of the brain’s sleep-wake regulation. It has two main types:

• Narcolepsy Type 1: Includes cataplexy and low hypocretin levels

• Narcolepsy Type 2: Similar excessive sleepiness, but without cataplexy

Typical symptoms:

• Sudden sleep attacks during the day

• Cataplexy (sudden muscle weakness triggered by emotion)

• Sleep paralysis or vivid hallucinations when falling asleep or waking up

• Fragmented nighttime sleep

These symptoms can mimic panic attacks, psychosis, or dissociative episodes, leading patients to psychiatric care before a sleep disorder is considered.

🧠 Where the Confusion Happens

Sleep and mental health are deeply intertwined. Fatigue, poor focus, irritability, and low motivation are nonspecific symptoms that appear in both sleep disorders and psychiatric conditions.

Common misinterpretations include:

• IH mistaken for depression: “I sleep all the time, and I can’t get anything done.”

• Narcolepsy mistaken for anxiety or trauma responses: “I freeze or collapse when I get emotional.”

• Daytime sleepiness mistaken for ADHD: “I can’t focus or stay awake during meetings.”

Without careful assessment, and sometimes a referral for a sleep study, (polysomnography and MSLT), the real cause can be missed.

🔍 Why This Matters

Misdiagnosis delays proper treatment and can lead to frustration for both patients and clinicians. Effective management may involve:

• Optimizing sleep hygiene

• Considering wake-promoting agents (e.g., modafinil)

• Coordinating care with a sleep medicine specialist

• Providing psychoeducation to reduce stigma and misunderstanding

🌞 Takeaway

When a patient’s “fatigue” or “low mood” doesn’t fit the usual psychiatric pattern, or when medications fail to help, it’s worth asking: Could this be a sleep disorder?

Sleep and mental health are partners, not competitors. Recognizing that connection can change lives. and help our patients finally wake up feeling rested. 😌