There are an estimated 140,000 people with<unk> -24—both sighted and blind—in the European Union, a total prevalence of approximately 3 per 10,000, or 0.03%. It is unknown how many individuals with this disorder do not seek medical attention, so incidence may be higher. The European portal for rare diseases, Orphanet, lists<unk> -24 as a rare disease by their definition: fewer than 1 affected person for every 2000 population. The US National Organization for Rare Disorders (NORD) lists<unk> -24 as a rare disease by its definition. Blind While both sighted and blind people are diagnosed with<unk> -24, the disorder is believed to affect up to 70% of totally blind individuals. It is estimated by researchers that of the 1.3 million blind people in the U.S., 10% have no light perception at all. Of that group, it is estimated that approximately half to three-quarters, or 65,000 to 95,000 Americans, suffer from<unk> -24.
Non-24-hour sleep–wake disorder
Circadian rhythm sleep disorder
Delayed sleep phase disorder
Irregular sleep–wake rhythm
Advanced sleep phase disorder
Shift work sleep disorder
Excessive daytime sleepiness
Sleep state misperception