The use of pharmacological approaches to treatment are less successful due to the risks of administering sleep-promoting agents early in the morning. Additional methods of treatment, like timed melatonin administration or hypnotics have been proposed, but determining their safety and efficacy will require further research. Unlike other sleep disorders, ASPD does not necessarily disrupt normal functioning at work during the day and some patients may not complain of excessive daytime sleepiness. Social obligations may cause an individual to stay up later than their circadian rhythm requires, however, they will still wake up very early. If this cycle continues, it can lead to chronic sleep deprivation and other sleep disorders. Epidemiology
ASPD is more common among middle and older adults. The estimated prevalence of ASPD is about 1% in middle-age adults, and is believed to affect men and women equally. The disorder has a strong familial tendency, with 40-50% of affected individuals having relatives with ASPD. A genetic basis has been demonstrated in one form of ASPD, familial advanced sleep phase disorder (FASPS), which implicates missense mutations in genes hPER2 and CKIdelta in producing the advanced sleep phase phenotype. The identification of two different genetic mutations suggests that there is heterogeneity of this disorder. Familial advanced sleep phase syndrome
FASPS symptoms
While advanced sleep and wake times are relatively common, especially among older adults, the extreme phase advance characteristic of familial advanced sleep phase syndrome (also known as familial advanced sleep phase disorder) is rare.
Treatment with sleep and wake scheduling and bright light therapy can be used to try to delay sleep phase to a more conventional time frame, however treatment of FASPS has proven largely unsuccessful. Bright light exposure in the evening (between 7:00 and 9:00), during the delay zone as indicated by the phase response curve to light, has been shown to delay circadian rhythms, resulting in later sleep onset and offset in patients with FASPS or other advanced sleep phase disorders. Discovery
In 1999, Louis Ptáček conducted a study at the University of Utah in which he coined the term familial advanced sleep phase disorder after identifying individuals with a genetic basis for an advanced sleep phase. The first patient evaluated during the study reported "disabling early evening sleepiness" and "early morning awakening"; similar symptoms were also reported in her family members. Consenting relatives of the initial patient were evaluated, as well as those from two additional families. The clinical histories, sleep logs and actigraphy patterns of subject families were used to define a hereditary circadian rhythm variant associated with a short endogenous (i.e. internally-derived) period. The subjects demonstrated a phase advance of sleep-wake rhythms that was distinct not only from control subjects, but also to sleep-wake schedules widely considered to be conventional. The subjects were also evaluated using the Horne-Östberg questionnaire, a structured self-assessment questionnaire used to determine morningness-eveningness in human circadian rhythms. The Horne-Östberg scores of first-degree relatives of affected individuals were higher than those of marry-in spouses and unrelated control subjects.