Object: Recent prospective studies have shown that the rupture rate of small unruptured intracranial aneurysms is very low. However, awareness of harboring an aneurysm often provokes anxiety and depression, which may reduce the quality of life (QOL).
Methods: This cross-sectional study enrolled 52 patients who had previously been notified of the presence of untreated unruptured aneurysms. A Markov model was constructed to simulate the natural history over time, and the age- and size-specific loss of quality-adjusted life year (QALY) caused by the aneurysms was calculated. Preference-based subjective QALY losses (PSG and PTTO) were assessed using the standard gamble (SG) and time trade-off (TTO) according to patient's own perceptions.
Results: Calculated theoretical QALY losses were relatively small with median values of 0.4 years (interquartile range [IQR] 0.1-1.0 years) and 1.9 % (IQR 1.1-3.7 %) of expected lifetime. The median values of PSG and PTTO were 10.0 % (IQR 5.0-14.3 %) and 19.5 % (IQR 9.0-25.0 %), respectively. Although theoretical QALY losses were smaller in the patients with small aneurysms (<5 mm) than in patients with medium ∼ large aneurysms (≥5 mm), the PSG and PTTO were almost the same in both groups. The discrepancy between theoretical and subjective QALY losses was prominent in patients with small aneurysms.
Conclusions: Notification of unruptured aneurysms exerts a significant psychological burden, and excessively reduces the QOL relative to the theoretical risks. The present study suggests that neurosurgeons should reconsider the method used to inform patients of small lesions with low risk of severe consequences.