The obesity pattern of idiopathic intracranial hypertension in men

Background: Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is a disorder of unknown etiology, predominantly affecting obese women of childbearing age. IIH is uncommon in men, with a reported female-to-male ratio of 8:1. The pathogenesis of IIH is poorly understood. Several mechanisms have been suggested, but no one mechanism has been able to account for all manifestations of the disease. This research aims to characterize the obesity phenotype(s) of men with IIH in order to find potential inducers for this disease. Methods: This is a cross-sectional study based on subjects' medical records. It compared anthropometric parameters between 22 men with IIH, 60 healthy men, and 44 females with IIH. One-way analysis with age and body mass index included as covariates was applied for the assessment of the difference in fat distribution among the three groups. Results: No significant differences were observed between the male IIH cohort and healthy males for age, BMI, and waist measurements, whereas hip circumference was significantly larger in the IIH cohort (114 ± 13 vs. 104 ± 16 cm; respectively, p < 0.001). Consequently, waist-to-hip ratio (WHR) was significantly lower in the male IIH cohort (0.88 ± 0.08 vs. 0.95 ± 0.12; p < 0.001). While no significant differences were observed for age and hip measurements between male IIH and female IIH cohorts, waist circumference and waist-to-hip ratio (WHR) were significantly larger in the male cohort (102 ± 19 cm vs. 95 ± 13 cm, p < 0.001; 0.88 ± 0.08 vs. 0.78 ± 0.06, p < 0.001, respectively). All these results maintained after adjustment for age and BMI. Conclusions: This is the first report of body fat distribution patterns in men with IIH. Whereas male IIH have larger central fat deposition than female IIH patients, abdominal fatness is less accentuated in IIH men compared to normal obese men. The later observation is in agreement with similar results regarding female IIH patients. We believe that these findings justify further investigation into the involvement of various fat depots in the pathogenesis of IIH in men and women alike.