The number of new cases per year of<unk>  is strongly determined by sex and body weight. The figures in females are in women between 20 and 45 years old. On average,<unk>  occurs in about one per 100,000 people, and can occur in children and adults. The median age at diagnosis is 30.<unk>  occurs predominantly in women, especially in the ages 20 to 45, who are four to eight times more likely than men to be affected. Overweight and obesity strongly predispose a person to<unk> : women who are more than ten percent over their ideal body weight are thirteen times more likely to develop<unk> , and this figure goes up to nineteen times in women who are more than twenty percent over their ideal body weight. In men this relationship also exists, but the increase is only five-fold in those over 20 percent above their ideal body weight. Despite several reports of<unk>  in families, there is no known genetic cause for<unk> . People from all ethnicities may develop<unk> . In children, there is no difference in incidence between males and females. From national hospital admission databases it appears that the need for neurosurgical intervention for<unk>  has increased markedly over the period between 1988 and 2002. This has been attributed at least in part to the rising prevalence of obesity, although some of this increase may be explained by the increased popularity of shunting over optic nerve sheath fenestration.
Idiopathic intracranial hypertension
Brain tumor
Intracranial hypertension syndrome
Arachnoiditis
Meningitis
Subarachnoid hemorrhage
Migraine
Infectious intracranial aneurysm