What Is Nocturnal Panic Disorder?

It's 2 a.m. and suddenly you're awakened by a tightness in your throat so you can't breathe. Your heart races and you are covered with sweat. Heart attack, or nocturnal panic attack?

If you have had daytime panic attacks, you may be somewhat familiar with the feelings of terror and disorientation. If not, you may think you are having a heart attack and become convinced you are dying.

Because the symptoms of heart attack and nocturnal panic attack mimic each other, it may be hard at first to know the difference. The good news is that nocturnal panic attacks don't kill sufferers, although they are certainly terrifying.

Signs and symptoms

• Nocturnal panic attacks are usually associated with shortness of breath or choking sensations, sweating, racing heartbeat, trembling or shaking, dizziness and a palpable fear of dying. Because some of the signs of nocturnal panic attack mimic those of a heart attack, the experience of panic itself may raise the level of anxiety and exacerbate the attack.

  Most people who experience nocturnal panic attacks also have attacks during the day, according to the Mayo Clinic. Nighttime panic attacks are less common than daytime attacks, but can be far more disturbing because the sufferer awakens suddenly without contextual or environmental cues.

Causes

• Differential diagnosis of nocturnal panic attack is made by ruling out hyperthyroidism (overactive thyroid), hypoglycemia (low blood sugar) and post-traumatic stress disorder (PTSD).

  Other sleep disorders may have signs that mimic panic attacks, and can even trigger an attack. These include obstructive sleep apnea, gastrointestinal reflux disease (GERD), laryngospasm (sudden contraction of the vocal cords) and nocturnal seizures.

  Sleep research points to a specific area of the brain (medulla) that is sensitive to fluctuations in blood levels of carbon dioxide. When oxygen levels are low because of shallow breathing and higher levels of carbon dioxide, the brain triggers more rapid respiration (hyperventilation) to raise oxygen levels. This can also initiate a panic attack.

Paradoxical response

• Paradoxically, in some people the relaxation that comes with sleep triggers their overactive vigilance mechanism to cause a panic attack. In other words, these people experience a fear of loss of vigilance over threats and can not allow themselves to really relax.

Behavioral treatment

• In a research paper presented at a meeting of the Association for Advancement of Behavior Therapy (Hsu A, Sandbrand D, Nazarian M, Hurtado M, Yocum M, Craske MG, "Does cognitive behavior change predict treatment outcome for noctrurnal panic?"), scientists found that cognitive behavior therapy can be used effectively to treat nocturnal panic disorder.

  Investigators modified a standard 11-session cognitive behavioral program for panic disorder to include education about nocturnal panic attacks, sleep hygiene, cognitive alteration of sleep phobias, breathing exercises and relaxation practices. Of the small sample of 22 patients, 76 percent reported no more nocturnal panic attacks after the source, 56 percent had no daytime panic attacks, and 60 percent no longer could be classified as having a panic disorder.

Other therapies

• Other treatments for nocturnal panic attacks include administration of anti-anxiety medications, meditation and relaxation practices, listening to soothing music before bedtime, eliminating nighttime consumption of caffeine and chocolate, breathing exercises and control of any disruptive breathing disorders (parasomnias), as well as medications to control gastrointestinal reflux (GERD).