Longitudinal visual outcomes in idiopathic intracranial hypertension: the role of early prognostic indicators and risk stratification in disease management.

Background: Idiopathic intracranial hypertension (IIH) is increasingly prevalent, yet longitudinal outcome data are scarce. This study aimed to characterise demographic and longitudinal clinical changes in a cohort of patients with IIH.

Methods: Retrospective cohort analysis on adult patients diagnosed with IIH (Friedman criteria) enrolled in the neuro-ophthalmology database (NODE) across two tertiary centres. Baseline demographic data was obtained at first assessment, with clinical and paraclinical outcomes collected longitudinally. Multivariable statistical analysis identified factors associated with poorer visual outcomes.

Results: A total of 221 patients were included. 91.8% were female (ratio 11:1). Mean age at presentation was 29.2 ± 8.1 years with mean body mass index (kg/m) at diagnosis of 38.7 ± 9.4. Headache was the most common symptom. Papilloedema was found in 95.5% of patients at baseline. Mean CSF opening pressure was 32.67 ± 6.85cmCSF (range 25-76). Visual outcomes remained stable over time. Trajectory plots showed no deviations in visual acuity, while regression models found no associations with sex, site or age. A higher retinal nerve fibre layer thickness and greater baseline Frisen grade were associated with worse outcomes. Baseline papilloedema grade and CSF opening pressure emerged as early prognostic indicators, aiding risk stratification for those with a greater probability of persistent optic nerve abnormalities including higher retinal nerve fibre layer elevation and sustained atrophic changes over time.

Conclusions: This study offers insights into visual outcomes in IIH, emphasising the importance of early recognition, risk stratification, and intervention in those with a more severe clinical phenotype at presentation.