Abstract 1122‐000130: Prediction of Risk of Rupture of Intracranial Aneurysms in a Latin‐American Population: A Restrospective Study
Authors: Calienes Aaron Rodriguez , Rodriguez‐Calienes Aaron , Saal‐Zapata Giancarlo , Malaga Marco , Rodriguez‐Varela Rodolfo 
Published: December 2021

Introduction
: The Population, Hypertension, Age, Size, Earlier Subarachnoid Hemorrhage (SAH), Site (PHASES) score was developed in North America, Europe, and Japan and it is a widely used model in day‐to‐day clinical practice for intracranial aneurysm (IA) rupture risk stratification. Here, we aimed to determine the predictors of aneurysm rupture and assess the components of the PHASES score in a Latin American population.

Methods
: Four hundred eighty‐six Peruvian patients presented at our institution with ruptured IAs between 2010 and 2020. We retrospectively collected the following variables: age, sex, a hypertension or diabetes mellitus history, previous SAH, the aneurysm size in millimeters (<5, 5–6.9, 7–9.9, 10–19.9, and ≥20), aneurysm morphology (saccular or non‐saccular), neck diameter (≤4 and >4), presence of a pseudoaneurysm, and aneurysm location. We then performed two separate multivariate analysis. For the first one, we included variables using a stepwise approach with a cut‐off p‐value of 0.2 in univariate logistic regression. For the second one, we evaluated the PHASES score components. A p‐value of 0.05 was considered statistically significant.

Results
: The median age was 56 years old, and 114 females were included. One hundred seventy‐five patients had a hypertension history, 21 had a diabetes history, and 11 had a previous SAH. Seventy‐eight patients had an aneurysm with <5mm, 118 with 5–6.9mm, 125 with 7–9.9mm, 85 with 10–19.9, and 10 patients with an aneurysm >20mm. There were 372 patients with a saccular aneurysm and an associated pseudoaneurysm was found in 197 patients. The most common location was posterior communicating artery (n = 219), followed by the anterior cerebral artery (n = 125), the middle cerebral artery (MCA) (n = 58), branches from the posterior circulation (n = 33), and finally by a paraclinoid aneurysm (n = 33). In our initial multivariate analysis, only the presence of an associated pseudoaneurysm was an independent predictor for aneurysm rupture (OR 7.93; 95% CI 3.45 – 18.25). An age >70 years (OR 1.12; 95% CI 0.3 – 4.12), the male sex (OR 1.39; 95% CI 0.54 – 3.62), a hypertension history (OR 1.14; 95% CI 0.53 – 2.44), a size of 10–20mm (OR 1.46; 95% CI 0.46‐ 4.64), and location in the MCA (OR 1.07; 95% CI 0.25 – 4.57) also predicted a higher rupture risk but without statistical significance. When we performed a multivariate logistic regression of the factors making up the PHASES score, we found that only the age (OR 1.79; 95% CI 1.11‐ 2.88) and a hypertension history (OR 1.61; 95% CI 1.14 – 2.27) were independent predictors of aneurysm rupture.

Conclusions
: Based on our findings and its limitations, we observed that the presence of an associated pseudoaneurysm was a predictor for aneurysm rupture. Moreover, we found that only two of the five components of the PHASES score were predictors of the event in our population: the age and a hypertension history. Therefore, new research should be carried out in the Latin American population to establish predictors for the development of clinical predictive models in this field.