Predictors of admission and shunt revision during emergency department visits for shunt-treated adult patients with idiopathic intracranial hypertension

OBJECTIVE Factors associated with emergency department admission and/or shunt revision for idiopathic intracranial hypertension (IIH) are unclear. In this study, the associations of several factors with emergency department admission and shunt revision for IIH were explored. METHODS The authors performed a retrospective review of 31 patients (169 total emergency department visits) who presented to the emergency department for IIH-related symptoms between 2003 and 2015. Demographics, comorbidities, symptoms, IIH diagnosis and treatment history, ophthalmological examination, diagnostic lumbar puncture (LP), imaging findings, and data regarding admission and management decisions were collected. Multivariable general linear models regression analysis was performed to assess the predictive factors associated with admission and shunt revision. RESULTS Thirty-one adult patients with a history of shunt placement for IIH visited the emergency department a total of 169 times for IIH-related symptoms, with a median of 3 visits (interquartile range 2-7 visits) per patient. Five patients had more than 10 emergency department visits. Baseline factors associated with admission included male sex (OR 10.47, 95% CI 2.13-51.56; p = 0.004) and performance of an LP (OR 3.10, 95% CI 1.31-7.31; p = 0.01). Contrastingly, older age at presentation (OR 0.94, 95% CI 0.90-0.99; p = 0.01), and a greater number of prior emergency department visits (OR 0.94, 95% CI 0.89-0.99; p = 0.02) were slightly protective against admission. The presence of papilledema (OR 11.62, 95% CI 3.20-42.16; p < 0.001), Caucasian race (OR 40.53, 95% CI 2.49-660.09 p = 0.009), and systemic hypertension (OR 7.73, 95% CI 1.11-53.62; p = 0.03) were independent risk factors for shunt revision. In addition, a greater number of prior emergency department visits (OR 0.86, 95% CI 0.77-0.96; p = 0.009) and older age at presentation (OR 0.93, 95% CI 0.87-0.99; p = 0.02) were slightly protective against shunt revision, while there was suggestive evidence that presence of a programmable shunt (OR 0.23, 95% CI 0.05-1.14; p = 0.07) was a protective factor against shunt revision. Of note, location of the proximal catheter in the ventricle or lumbar subarachnoid space was not significantly associated with admission or shunt revision in the multivariable analyses. CONCLUSIONS The decision to admit a shunt-treated patient from the emergency department for symptoms related to IIH is challenging. Knowledge of factors associated with the need for admission and/or shunt revision is required. In this study, factors such as male sex, younger age at presentation, lower number of prior emergency department visits, and performance of a diagnostic LP were independent predictors of admission. In addition, papilledema was strongly predictive of the need for shunt revision, highlighting the importance of an ophthalmological examination for shunt-treated adults with IIH who present to the emergency department.