Prediction of Outcomes for Ruptured Aneurysm Surgery: The Southwestern Aneurysm Severity Index. Issue 3 (March 2019) - Ban, Vin Shen
Abstract : Background and Purpose—: Predicting long-term functional outcomes after intracranial aneurysmal rupture can be challenging. We developed and validated a scoring system—the Southwestern Aneurysm Severity Index—that would predict functional outcomes at 1 year after clipping of ruptured aneurysms. Methods—: Ruptured aneurysms treated microsurgically between 2000 and 2014 were included. Outcome was defined as Glasgow Outcome Score (ranging from 1, death, to 5, good recovery) at 1 year. The Southwestern Aneurysm Severity Index is composed of multiple prospectively recorded patient demographic, clinical, radiographic, and aneurysm-specific variables. Multivariable analyses were used to construct the best predictive models for patient outcomes in a random 50% of the cohort and validated in the remaining 50%. A scoring system was created using the best model. Results—: We identified 527 eligible patients. The Glasgow Outcome Score at 1 year was 4 to 5 in 375 patients (71.2%). In the multivariable logistic regression, the best predictive model for unfavorable outcome included intracerebral hemorrhage (odds ratio [OR], 2.53; 95% CI, 1.55−4.13), aneurysmal size ≥20 mm (OR, 6.07; 95% CI, 1.92−19.2), intraventricular hemorrhage (OR, 2.56; 95% CI, 1.15−5.67), age >64 (OR, 3.53; 95% CI, 1.70−7.35), location (OR, 1.82; 95% CI, 1.10−3.03), and hydrocephalus (OR, 2.39; 95% CI, 1.07−5.35). The Southwestern Aneurysm Severity Index predicts Glasgow Outcome Score at 1 year with good discrimination (area under the receiver operating characteristic curve, derivation: 0.816, 95% CI, 0.759−0.873; validation: 0.803, 95% CI, 0.746−0.861) and accurate calibration ( R 2 =0.939). Conclusions—: The Southwestern Aneurysm Severity Index has been internally validated to predict 1 year Glasgow Outcome Scores at initial presentation, thus optimizing patient or family counseling and possibly guiding therapeutic efforts. Abstract : Supplemental Digital Content is available in the text.