Background The prospective single-arm non-randomized SCENT trial on flow diverter (FD) treatment for intracranial aneurysms (IA) was analyzed for patients? age and IA characteristics impacting stroke and occlusion rates over 5 years. Methods The impact on major ipsilateral stroke and IA occlusion was studied by stratifying age as ≤ 65 versus >65. Kaplan-Meier estimates of time to both endpoints, stratified by age group, were created. Univariate predictors of time-to-stroke were identified by including candidate variables in univariable proportional hazards regression models. Those variables found to be significant at the univariate level were entered into a multivariable survival model to identify independent predictors. The stepwise selection produced a final reduced model with a significance level to both enter and stay set at 0.05. Results Of 180 patients with large or giant IA enrolled, 119 subjects were ≤ 65, while 61 were > 65. When parent-artery stenosis and IA size were entered into a multiple-stepwise survival model, only stenosis remained as an independently significant predictor of time-to-stroke. At 3-year follow-up, there were 23 strokes (12.8%), 11 occurring in subjects ≤ 65; seniors were at greater risk (HR1.96, 95% CI 0.83-4.78). Four patients (4/180; 2.2%) experienced aneurysm rupture within the first week post-treatment, with 3 being ≤ 65 and the fourth aged 66. No new strokes were reported between 3 and 5 years. In seniors, a complete IA occlusion was documented in 60.0%(33/55), 67.6%(25/37), and 85.7%(18/21) at 12, 36, and 60 months, respectively, as compared to 79.1%(87/110), 82.5%(66/80), and 91.8%(56/61) for younger subjects. The time to complete IA occlusion was shorter in younger patients (HR1.53, 95% CI 1.07-2.19). Conclusions Age > 65 and parent artery stenosis are related to an increased risk of stroke in patients treated with an FD for IA and predictive of incomplete and increased time to healing. With demographic shifts, future treatments need to address expedited and improved healing.

The authors have declared no competing interest.

https://www.clinicaltrials.gov NCT01716117

Stryker NV funded the SCENT study. No funds or grants were received for manuscript preparation or statistical analysis or the subgroup analysis.

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