The incidence of idiopathic intracranial hypertension in Israel from 2005 to 2007: results of a nationwide survey

Background and purpose: Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is a disorder related to increased intracranial pressure without clinical, laboratory or radiological evidence of an intracranial space occupying lesion or cerebral sinus vein thrombosis, predominantly affecting obese women of childbearing age. Our aim was to determine the incidence and clinical features of IIH in Israel. Methods: In a cross-sectional study, all medical records of patients discharged from the hospital with a primary diagnosis of IIH during 2005-2007 were reviewed. Results: Four hundred and twenty-eight patients with a new onset of IIH were diagnosed. The average annual incidence rate was 2.02 per 100 000 with an incidence of 3.17 per 100 000 for women and 0.85 per 100 000 for men. The incidence rate in females of childbearing age (18-45) was 5.49 per 100 000. The female to male ratio for >17 years old was 6.1:1 (252 females and 41 males) and 2.1: 1 (60 females and 28 males) for ages 11-17. Obesity was documented in 83.4% of patients. Body mass index (BMI) data were available for 159 (37.1%) patients; of these, 59.1% had a BMI >= 30. Conclusion: The incidence of IIH in Israel has increased during the last decade. This finding could be related to the increasing rates of obesity. The association of IIH and obesity should be further explored especially with regard to the effect of weight reduction for primary prevention.