FASPS

Familial Advanced Sleep Phase Syndrome (FASPS) is a rare circadian rhythm sleep disorder characterized by a significantly advanced sleep-wake cycle. Individuals with FASPS typically experience early evening sleepiness and early morning awakening. This condition is often inherited in an autosomal dominant manner.

Symptoms

The primary symptom of FASPS is an advanced sleep phase, where individuals feel the need to go to sleep and wake up much earlier than the societal norm. This can lead to difficulties in social and occupational functioning due to the misalignment with typical schedules. Other symptoms may include:

• Early evening sleepiness, often around 7-9 PM.
• Early morning awakening, typically between 2-5 AM.
• Difficulty staying awake in the evening and staying asleep in the early morning.

Causes

FASPS is primarily caused by mutations in genes that regulate the circadian clock. The most commonly implicated genes include:

• PER2 (Period Circadian Regulator 2)
• CSNK1D (Casein Kinase 1 Delta)

These genetic mutations lead to alterations in the proteins that control the timing of the circadian clock, resulting in an advanced sleep phase.

Diagnosis

Diagnosis of FASPS typically involves a combination of:

• Detailed sleep history and sleep diary.
• Actigraphy to monitor sleep-wake patterns.
• Polysomnography to rule out other sleep disorders.
• Genetic testing to identify mutations in circadian clock genes.

Treatment

There is no cure for FASPS, but several strategies can help manage the symptoms:

• Chronotherapy: Gradually delaying sleep time to align with a more conventional schedule.
• Light therapy: Exposure to bright light in the evening to delay the circadian phase.
• Melatonin: Administration in the early morning to help shift the sleep phase.

Related Conditions

FASPS is part of a broader category of circadian rhythm sleep disorders, which also includes:

• Delayed Sleep Phase Disorder (DSPD)
• Non-24-Hour Sleep-Wake Disorder
• Irregular Sleep-Wake Rhythm Disorder

See Also

• Circadian rhythm
• Sleep disorder
• Genetic disorder
• Chronotherapy
• Light therapy