What are the risk factors for advanced sleep phase disorder (ASPD)?
As with DSPD, the etiology of ASPD is unknown. Studies suggest a contribution of physiologic (e.g., a shortened free-running period) and genetic (circadian clock gene polymorphism) factors.30
Autosomal-dominant inheritance of ASPD has been demonstrated in familial cases.31 32
30. Toh KL, Jones CR, He Y, et al. An hPer2 phosphorylation site mutation in familial advanced sleep phase syndrome. Science. 2001;291:1040-1043
31. Reid KJ, Chang AM, Dubocovich ML, et al. Familial advanced sleep phase syndrome. Arch Neurol. 2001;58:1089-1094.
32. Satoh K, Mishima K, Inoue Y, Ebisawa T, Shimizu T. Two pedigrees of familial advanced sleep phase syndrome in Japan. Sleep. 2003;26:416-417.