Walsh & Hoyt: Pseudotumor Cerebri: Epidemiology

PTC affects infants, children and young adults but rarely has onset over age 45 years. The idiopathic form (IIH) is typically a disorder of obese females of childbearing age. The incidence of PTC varies throughout the world. Two studies in the United States estimated the incidence at approximately 0.9 per 100,000 in the general population with a female male ratio of 8 1. The incidence rises to 3.5 per 100,000 in women aged 20 to 44 years, and further increases to 13 per 100,000 in women who are 10% over ideal weight, and 19 per 100,000 in women who are 20% over ideal weight. The incidence in Benghazi, Libya was 2.2 per 100,000 in the general population, 4.3 per 100,000 in women, and 21.4 per 100,000 in women aged 15-44 years who were 20% over ideal weight. In Israel, whose population is a mixture of people originating from various Eastern and Western countries, the incidence was similar to that in western populations with a preponderance of obese women.