Introduction: Numerous previous studies have discussed the correlation between patient age and aneurysm rupture. However, the existing base of knowledge regarding the relationship between patient age and aneurysm growth, specifically growth rate, is significantly smaller. The objective of this study is to examine the correlation between patient age and aneurysm growth in order to help devise better clinical management strategies.
Hypothesis: Growing aneurysms in older patients will exhibit a higher mean growth rate relative to those in younger patients.
Methods: In this study, the records of 361 patients between the age of 40 and 97 at the time of initial diagnosis with unruptured intracranial aneurysms in the UCLA Medical Center between January 2005 and December 2015 were reviewed. These patients were continuously followed using CTA neurovascular imaging, ending when the patient either received surgical or endovascular treatment or discontinued follow-up visits.
Results: A total of 496 UIA in the 361 patients were classified into four groups by patient age (40-49, n=56; 50-59, n=120; 60-69, n=145; 70+, n=175). Incidence of growth was 14.29%, 11.67%, 8.28%, and 12.57% for the 40-49, 50-59, 60-69, and 70+ groups, respectively. Growth rates were 0.30±0.12, 0.58±0.42, 0.90±0.72, and 0.78±0.75 mm/yr for the 40-49, 50-59, 60-69, and 70+ groups, respectively. Differences in growth rates were not significant between the four groups (ANOVA, p=0.15). However, when patients were divided by age 50 years, growth rates were significantly higher in the 50+ group (p<0.05).
Conclusion: Although there was a high level of variation in growth rate between individual cases, this study found that patients with growing aneurysms over the age of 50 are at a higher risk for rapid aneurysm growth compared to younger patients, a finding that may prove helpful in developing clinical management protocols.