Influence of comorbidities on treatment of unruptured intracranial aneurysms in the elderly

Current evidence does not conclusively justify conservative management of unruptured intracranial aneurysms (UIA) in the elderly (age ≥ 65 years). To rationalise intervention, the authors investigated the role of age and comorbidity burden on treatment outcomes. A retrospective chart review for consecutive cases of UIAs treated in the elderly between 2007 and 2018 was performed. Preoperative Charlson Comorbidity Index (CCI) and Neurovascular Comorbidities Index (NCI) were calculated. Standard statistical methods with univariate and multiple logistic regression were used. A total of 123 patients (46 surgery, 77 endovascular) with 131 UIAs were treated. The mean age was 70.6 ± 4.1 years, and 90 patients were female (73.1%). The mean aneurysm size was 8.6 ± 5.0 mm, and the mean follow up period was 22.9 ± 21.3 months. The rates of poor outcome (mRS > 1) at discharge, 6 weeks and 6 months were 9.8%, 5.8% and 3.6%, respectively. There was no difference in outcomes between surgical and endovascular treatment. Correlation and regression analyses revealed that aneurysm size, higher preoperative comorbidity index (CCI > 4), and endovascular treatment with a stent or flow diverter (p = 0.009, 0.02, and 0.005, respectively) were associated with a poor outcome. When adjusted in a multivariate analysis, only high comorbidity burden (CCI > 4) predicted unfavourable outcome (p = 0.01). Elderly patients who undergo treatment for UIAs are at high risk of postoperative deterioration. Careful preoperative case selection based on comorbidity burden, rather than chronological age, would be useful for improved risk stratification.