Who does narcolepsy affect?

• Narcolepsy affects both men and women equally
• The initial symptoms of narcolepsy can occur in early adolescence but the most common age of diagnosis is between 20 and 40 years old
• Narcolepsy affects approximately 0.05% of the population worldwide (1 in 2000)
• It has been estimated that at least 25,000 people in the UK suffer from narcolepsy with 80% of those currently being untreated
• Narcolepsy appears throughout the world in every racial and ethnic group. But occurrence rates vary among populations. Compared to the U.K. population, for example, the occurrence rate of narcolepsy is substantially lower in Israel (about 1 per 500,000 people) and considerably higher in Japan (about 1 per 600).

Age at onset of Narcolepsy

(Adapted from Narcolepsy Eds: Guilleminault C et al, New York:Spectrum Publications, 1976)

The above graph shows that most patients experience the onset of symptoms of narcolepy between the ages of 15 and 30. However, onset at young childhood and middle age does sometimes occur. Studies have shown that it may take up to 12 years from the development of the first symptom to a definitive diagnosis of the condition.