CLINICAL QUESTION: Should we screen for intracranial aneurysms in first-degree relatives of patients with subarachnoid hemorrhage?
BACKGROUND: A subarachnoid hemorrhage from a ruptured intracranial aneurysm is often a devastating event, with approximately 70% of affected patients dying or becoming functionally dependent. A family history of subarachnoid hemorrhage is a significant risk factor, associated with a 3- to 7-fold higher incidence. Previous studies have reported that intracranial aneurysms are found in 8% of persons with 2 relatives who have hemorrhaged. The investigators studied the risks and benefits of screening first-degree relatives (parents, siblings, or children) for aneurysms with magnetic resonance angiography (MRA).
POPULATION STUDIED: Index patients admitted for subarachnoid hemorrhage were consecutively identified at one of 2 Dutch academic health centers. The mean age of the index patients was 52 years, and 69% were women. One hundred seventy-two of 193 had living first-degree relatives and agreed to participate. Six hundred twenty-six of the 980 known relatives were screened; they were aged 20 to 70 years (mean = 41 years), and none had contraindications to MRA or surgery. The vast majority of screened relatives were either siblings or children of the index patients, and 52% were women.
STUDY DESIGN AND VALIDITY: If a definite aneurysm was seen with MRA, conventional angiography with neurosurgical consultation was recommended. Possible aneurysms were screened again with MRA 6 to 12 months later. The investigators reported the outcome of screening and surgical intervention in those that underwent surgery. No follow-up assessments were performed in relatives with normal findings or those with aneurysms who did not undergo surgery; this complicates the interpretation of the results. On the basis of previous studies, the authors also attempted to estimate the risk of rupture, disability, and mortality if the aneurysms had not been detected. There was no control group that did not undergo screening. This also weakens the interpretation of the reported functional changes.
OUTCOMES MEASURED: The authors of the article report the prevalence of intracranial aneurysms, and for those who underwent surgery it outlines the intervention performed, neurologic disability 6 months postoperatively estimated risk of hemorrhage without surgery, and estimated life expectancy with and without surgery.
RESULTS: Among screened relatives, 25 of 626 (4.0%) had unruptured aneurysms, and 18 of these 25 underwent conventional angiography and surgery. Surgery was not indicated in 4 relatives, and the other 3 refused intervention. In 11 of the 18 subjects who underwent conventional angiography and surgery, disability was higher 6 months postoperatively than before angiography. One of these 11 had severe complications from conventional angiography. Four patients had specific postoperative sequelae of partial hemianopia, unilateral visual loss, or anosmia. The remaining 6 had nonspecific symptoms such as headache, fatigue, impaired concentration, or emotional problems.
The authors of this study do not support a general MRA screening policy for all first-degree relatives of patients with subarachnoid hemorrhage. The 2.5 years of added life expectancy for those who undergo surgery (or approximately 4 weeks per person screened) often comes with a price of prolonged neurologic impairment. This study provides concrete information for discussion between doctors and relatives of patients with subarachnoid hemorrhage. For every 1000 patients screened, 40 would have an aneurysm, 30 would have surgery, 10 to 20 would have neurologic sequelae from screening and intervention, and 7 would avoid a subarachnoid hemorrhage.