Comparison of Idiopathic Intracranial Hypertension Patients With and Without Anemia

Background: Idiopathic intracranial hypertension (IIH) is a condition of elevated intracranial pressure without an identifiable cause. It mostly affects young obese women but has been reported in individuals newly diagnosed with anemia or with chronic anemia. The relationship between anemia and IIH is not well elucidated. This study aims to characterize the course of IIH in anemic patients.Methods: Consecutive patients with IIH were recruited from neuro-ophthalmology clinics. Subsequent retrospective chart review obtained information on symptoms, complete blood counts (CBCs), visual acuity, visual fields, and optic disc edema at baseline and follow-up. Anemia was diagnosed by hemoglobin <120 g/L (women) and <130 g/L (men).Results: One hundred twenty-three patients with IIH were recruited for this study, and 22.8% (28/123) had anemia. More anemic individuals had mild-to-moderate visual acuity impairment (logarithm of minimum angle of resolution 0.3-1, P = 0.01) and worse automated mean deviation (P = 0.048). The median follow-up time was 47.4 weeks (interquartile range:20.1-91.8). Fifteen of 28 patients with anemia received anemia treatment and showed a trend toward increased hemoglobin. At follow-up, there were no differences in the visual acuity, but patients with anemia had worse automated mean deviation on visual fields (P = 0.045).Conclusions: IIH patients with anemia had worse visual function at presentation and worse final visual field parameters. This suggests that CBCs should be obtained for patients with papilledema because it may influence final visual outcome.