Endovascular Treatment of Ruptured Intracranial Aneurysms in Patients Aged 65 Years and Older
Follow-Up of 52 Patients After 1 Year
Background and Purpose— We sought to describe the clinical outcome and results obtained in the endovascular therapy of ruptured cerebral aneurysms in the elderly over an 8-year period. We compared endovascular therapy results in patients aged ≥65 and <65 years.
Methods— During 1993–1999, 52 patients aged 65 to 85 years (mean age, 71.5±4.7 years) were embolized with the use of Guglielmi detachable coils (group I). During the same period, 143 patients aged <65 years (mean age, 47±11 years) with ruptured cerebral aneurysm were treated with the same technique (group II). A clinical assessment was made on admission with the Hunt and Hess (HH) classification and again in the 12th month with the Glasgow Outcome Scale (GOS), with arteriographic control in months 3 and 12.
Results— In group I, clinical grades on admission were as follows: HH 1, 9.5%; HH 2, 33%; HH 3, 21%; HH 4, 34.5%; HH 5, 2%. Outcome was favorable in 48% of patients (GOS 1 or 2); the mortality rate was 23%. No rebleeding was observed. Patients presenting lesions ≥10 mm had an unfavorable outcome in >77% of cases. Thromboembolic complications were present in 13% of cases. In group II, clinical grades on admission were as follows: HH 1, 14.5%; HH 2, 47%; HH 3, 11%; HH 4, 24%; HH 5, 3.5%. Favorable outcome (GOS 1 or 2) was observed in 77% of cases, with 14% mortality. Complications due to the endovascular procedure were present in 4.2% of cases. Patients with HH grades 1 or 2 on admission showed a positive outcome (GOS 1 or 2) in 77% of cases in group I and in 88.5% of cases in group II. Mortality was 9% in the first subgroup compared with 2.8% in the second. Patients who had a high clinical grade on admission (HH 4 or 5) showed a favorable outcome (GOS 1 or 2) in 16% of cases in group I compared with 41% in group II.
Conclusions— Endovascular treatment of ruptured intracranial aneurysms in patients aged ≥65 years appears to be effective against rebleeding and represents an alternative to surgery. However, perioperative thromboembolic complications are more frequent in the elderly population.
The International Cooperative Study on the Timing of Aneurysm Surgery1 named the following as risk factors for death after subarachnoid hemorrhage (SAH): position of the aneurysm, thickness of subarachnoid clot on CT scan, clinical grade on admission, arterial hypertension, associated diseases, and increased age. As a result of the aging population in the West and the increased incidence of SAH in elderly patients, ruptured intracranial aneurysm is an increasingly frequent pathology in elderly people.
Different studies concerning SAH of aneurysmal origin in the elderly report clinical results after surgical treatment.2–8⇓⇓⇓⇓⇓⇓ However, endovascular treatment is now recognized as an alternative to surgical treatment, especially for patients in poor general health and for lesions of the posterior circulation. Nevertheless, no study assessing the results of endovascular treatment in relation to age have been undertaken, and the effectiveness of embolization in elderly patients is yet to be determined.
Subjects and Methods
During 1993–2000, 82 patients aged ≥65 years were hospitalized for SAH resulting from aneurysmal rupture. In each case, SAH was confirmed by CT scan or lumbar puncture. The intracranial aneurysm responsible for hemorrhage was revealed by cerebral angiography. Patients with fusiform, traumatic, or mycotic aneurysm were excluded from the study. On admission, clinical grade according to the Hunt and Hess classification,9 preexisting medical conditions, and tomodensitometric grade according to the Fisher classification were recorded.
Endovascular treatment (selective endovascular occlusion) of the aneurysm responsible for the hemorrhage was performed in 52 cases (group I). During the same period, 143 patients aged 4 to 64 years (mean age, 47±11 years) suffering from SAH resulting from ruptured aneurysm (group II) received the same endovascular treatment.
The clinical state of all patients treated by embolization was assessed 12 months after treatment with the use of the Glasgow Outcome Scale (GOS).10 Angiographic examinations were performed in months 3 and 12 after endovascular treatment. Aneurysms were divided into 3 groups according to the degree of occlusion: 0% to <90%, 90% to 99%, and total occlusion.
A logistic regression analysis and a χ2 test were performed for statistical evaluation. A probability value of 0.05 was used as the level of significance.
Characteristics of Patients Aged ≥65 Years
Ages of patients in this group ranged from 65 to 85 years (mean age, 71.5±4.75 years); approximately 70% of the patients were women (Table 1).
The main associated risk factors and preexisting illnesses were high blood pressure, smoking, and heart failure with or without irregularities of rhythm. Arterial hypertension was present in 27 patients (52%); 8 patients were smokers (15%), and 6 patients (11.5%) had a heart disorder. Other related pathologies were diabetes, migraine, and obesity (Table 2).
The aneurysm responsible for SAH was situated in the anterior circulation in 94.5% of cases; aneurysms of the anterior communicating artery represented 44.2% (Table 3). Aneurysms <10 mm represented 75% of treated lesions (Table 4). Patients presenting large and giant aneurysms had unfavorable outcome in >70% of cases (Table 5). Multiple aneurysms were revealed in 8 patients (15%).
Only aneurysms resulting in bleeding were treated. Embolization was not complicated by ruptured aneurysms, but thromboembolic complications were present in 7 cases (13%). Among these, 2 were totally regressive, 2 resulted in definitive neurological impairment, and 3 resulted in massive cerebral infarct causing the death of the patient despite arterial thrombolysis during the procedure.
Embolization resulted in ≥95% occlusion of the lesion in 81% of cases and a complete occlusion in 48.5% of cases. There was no recurrent hemorrhage after treatment. Aneurysmal repermeability by coil compaction was shown on angiographic control in 4 patients (7.5%). Three patients received 1 additional embolization, and 1 was treated surgically with clip placement.
Characteristics of Patients Aged <65 Years
The age of these patients ranged from 4 to 64 years (mean age, 47±11 years); unlike the older group, there was no predominance of 1 sex (Table 1).
Smoking was the most frequently encountered risk factor (21.7%), followed by arterial hypertension, which was present in 14.7% of cases (Table 2). The most frequent aneurysmal sites were the anterior communicating artery and the internal carotid artery (Table 3). Twenty-four patients (16.8%) presented multiple aneurysms. Aneurysms ≥10 mm were found in 18% of cases (Table 4); these lesions were associated with a favorable outcome in >80% of cases (Table 5). No giant aneurysm was present in this group. There were 6 complications due to the endovascular procedure (4.2% of patients): 2 cases of SAH after aneurysmal rupture when the first coil was placed, 3 patients with transitory neurological deficit, and 1 case of femoral pseudoaneurysm at the point of entry.
Repermeability because of coil compaction was observed on follow-up angiograms in 13 patients (9%): 3 were treated surgically with clip placement, and 10 were reembolized; After the second embolization, regrowth of the neck was observed in 2 patients; these 2 patients were treated surgically with clip placement.
Clinical and CT Grades on Admission in the 2 Groups
On admission, the clinical grade (Hunt and Hess) of patients in group I was higher than that in group II. More severe grades (Hunt and Hess 4 and 5) represented 36.6% of cases in group I compared with 27.3% in group II, while low grades (Hunt and Hess 1 and 2) represented 42.2% of cases in group I compared with 61.6% in group II (Table 6).
The CT scan on admission showed more abundant bleeding in patients aged ≥65 years; Fisher grade 4 cases represented 46% of group I, while they represented approximately 33% of group II (Table 7).
Clinical Outcome in the 2 Groups
There was a favorable outcome (GOS 1 and 2) in 48% of patients in group I and in 77% of patients in group II (Table 8). Global mortality in the first year was 23% in group I and 14% in group II. An analysis of clinical outcome in relation to clinical grade on admission showed important differences between the 2 groups (Table 9): a return to normal life (GOS 1) in patients showing good general health on admission (Hunt and Hess 1 and 2) was observed in 83% of cases in group II and only 54% of cases in group I.
For patients with a high clinical grade on admission (Hunt and Hess 4 and 5), an unfavorable outcome (GOS 3, 4, and 5) was shown in 84% in group I, with 42% mortality, while in group II unfavorable outcomes were observed in <60% of cases, and mortality was 33%. Similarly, in patients with a high clinical grade on admission, there was no patient with GOS 1 in group I, while GOS 1 represented 20% of cases in group II.
In both groups the clinical outcome of patients was correlated to the Fisher grade (Table 10). However, apart from patients classified as grade 1 in the Fisher classification who had a favorable outcome irrespective of age, with CT scores being equal, patients in group I showed a less positive clinical outcome than those in group II (Table 10).
To assess the influence of age (≥65 or <65 years), Hunt and Hess grade (from 1 to 5 [severe]), male sex, size of aneurysm, Fisher grade, number of aneurysms, and medical history on poor outcome (GOS ≥3), a logistic regression analysis was performed. With this statistical test, 4 variables were found to be discriminant for poor outcome, as shown in Table 11: age ≥65 years, severe Hunt and Hess grades, Fisher grades, and positive medical history.
The frequency of SAH increases with age.11–14⇓⇓⇓ This frequency, assessed at 2.8 per 100 000 inhabitants in the overall population, appears to be 7.8 per 100 000 inhabitants for those aged >70 years, according to Sacco et al,15 in the Framingham Study. Other epidemiological studies12–14⇓⇓ have also shown a frequency of SAH 3- to 4-fold higher in elderly patients. This increased incidence of SAH, associated with a similar increase in the prevalence of intracranial aneurysms in elderly populations16–18⇓⇓ and with an aging population in the West, makes ruptured aneurysm after the age of 65 years an increasingly frequent pathology in developed countries.
In the literature, chronic arterial hypertension is associated with SAH caused by aneurysm in 28% to 65% of cases.1,3⇓ In our series arterial hypertension was found in 52% of patients in group I and in 14.7% of patients in group II. In both groups arterial hypertension was not a prognostic factor because, in those patients affected, a favorable outcome (GOS 1 or 2) was noted in 50% of cases in group I and 61% in group II.
The different published series that have compared size of ruptured aneurysms in relation to age have not found any significant differences.3,6⇓ A comparable result was obtained in our study, with the number of aneurysms ≥10 mm in group I (21%) not significantly higher than in group II (18%) (P>0.25). In our study the size of the aneurysm responsible for bleeding was a prognostic factor in an elderly population because, for patients in group I, aneurysmal lesions ≥10 mm were associated with a negative outcome (GOS 3, 4, and 5) in 77% of cases, while smaller lesions showed a negative outcome in only 43.5% of cases (P<0.05). Similar results were found by Chung et al,4 who reported that an aneurysmal diameter >9 mm was a negative prognostic factor in SAH after age 70 years. In group II, however, clinical outcome of patients with aneurysms ≥10 mm was not significantly different from that of patients with smaller lesions (P>0.5).
Endovascular treatment appears to be effective against recurrent aneurysmal hemorrhage, since no patient in either group presented recurrent bleeding. These results were obtained in the oldest patients studied despite the high rate of partial occlusion after embolization in our series and despite clinical monitoring of patients up to a maximum of 8 years. However, we observed a percentage of perioperative thromboembolic complications in the group of oldest patients that was higher than that obtained in group II patients and higher than those reported in previous studies.19,20⇓ This high incidence of complications in the oldest patients is probably related, on the one hand, to atheromatous degeneration of the cerebral and cervical arteries and, on the other hand, to the sinuous nature of these arteries, which makes catheterization more difficult and the risk of embolism greater. Endovascular surgery in such circumstances requires greater precaution when catheterizing and a different anticoagulation protocol. In our department, the greater frequency of this type of complications led to an increase in the doses of anticoagulants during embolization in patients aged ≥65 years.
Clinical results after surgery of ruptured internal carotid artery have improved considerably over the past 20 years.1,7,8⇓⇓ This improvement was confirmed in elderly people by Inagawa,21 who, by comparing the results between 2 periods (1980–1985 and 1986–1990), observed an improvement in the outcomes of patients aged >70 years treated by surgery. Similarly, Swedish authors reported 74% good results in patients whose initial Hunt and Hess clinical grade was 1 or 2, with these results very close to those obtained in younger populations.22 For Stachniak et al,2 mortality after surgery was the only variable that differentiated populations aged ≥65 years from those aged <65 years, with 17% and 3% mortality, respectively. Such good results have not been reported by all investigators. In 1998 Yamashita et al14 reported a study of 3100 patients with internal carotid artery rupture treated surgically, in which 598 were aged >70 years; they found only 39% with favorable outcomes and a mortality >30% in this group. In our series 48% of patients aged ≥65 years had a GOS score of 1 and 2 at 1 year, and mortality was 23%. These results are comparable to those of the main recent surgical series, for which the favorable outcome rate (GOS 1 and 2) varies from 37% to 48%, and mortality varies from 16% to 35%.1–3,5,8,14⇓⇓⇓⇓⇓ A positive outcome (GOS 1 and 2) was shown for 77% of patients in good clinical condition on admission (Hunt and Hess grades 1 and 2) for patients in our series aged ≥65 years. A study involving 26 patients aged >70 years treated by embolization23 reported better results, with almost 85% positive outcome among patients with grades 1, 2, or 3 in the World Federation of Neurological Surgeons classification. In different published series and in our study, the long-term clinical condition of patients was evaluated with the GOS. Nevertheless, this type of classification does not enable us to assess the existence of certain cognitive disorders,24 and it is probable that a certain number of patients classified GOS 1 in our series and the literature present neuropsychological disorders that are handicapping to a greater or lesser extent. This problem of evaluation, which applies to all populations studied, is probably accentuated in an elderly population because neuropsychological problems after SAH seem to predominate in this age group.25,26⇓
Patients with a high clinical and CT grade on admission are more numerous in those aged 65 to 70 years.5,6,14⇓⇓ In our study patients in Hunt and Hess grades 4 and 5 were significantly more numerous in group I (P=0.05). This difference may partly explain the divergence in mortality between the 2 groups and the lower clinical results at 1 year in group I.
The clinical outcome of both groups was statistically different between the 2 groups: a favorable outcome (GOS 1 and 2) was observed in 48% of patients in group I and in 77% of patients in group II (P<0.001).
Similarly, if we study the clinical outcome of patients in relation to their clinical and CT grades on admission, clinical results at 1 year appear less good in group I than in group II for equivalent initial clinical and CT grades, and age ≥65 years is considered an independent risk factor associated with poor outcome (P<0.009). This difference in results between elderly and younger populations is observed equally in most surgical series published1,3,6⇓⇓; it is evidence of the negative role of old age in the prognosis for SAH, whatever the technique used for aneurysmal occlusion. Such increased morbidity, independent in our series of initial clinical grade, of initial volume of bleeding, and of the existence of preexisting pathological condition, appears to be linked to a decreased neuroplasticity of the aging brain and its reduced defenses in dealing with SAH. This “weakness” of the aging brain has similarly been observed in SAH of traumatic origin.27
Endovascular treatment seems to be effective in preventing recurrent aneurysmal bleeding and represents an alternative to surgery in the treatment of ruptured intracranial aneurysms in patients aged ≥65 years. The clinical results observed at 1 year after embolization are comparable to those obtained in the best surgical series and depend mainly on clinical and CT grades on admission. Endovascular treatment of intracranial aneurysms in patients aged ≥65 years presents more risks than in a younger population because of a greater frequency of thromboembolic complications.
- Received March 4, 2002.
- Revision received May 27, 2002.
- Accepted June 17, 2002.
- ↵Stachniak JB, Layon AJ, Day Al, Gallagher TJ. Craniotomy for intracranial aneurysm and subarachnoid hemorrhage. Stroke. 1996; 27: 276–281.
- ↵Martindale BV, Garfield J. Subarachnoid haemorrhage above the age of 59: are intracranial investigations justified? BMJ. 1978; 1: 465–466.
- ↵Sarti C, Tuomilehto J, Salomaa V, Sivenius J, Kaarsalo E, Narva EV, Salmi K, Torppa J. Epidemiology of subarachnoid hemorrhage in Finland from 1983 to 1985. Stroke. 1991; 22: 848–853.
- ↵Phillips LH, Whistnant JP, O’Fallon WM, Sundt TM. The unchanging pattern of subarachnoid hemorrhage in a community. Neurology. 1980; 30: 1034–1040.
- ↵Yamashita K, Kashiwagi S, Kato S, Takasago T, Ito H. Cerebral aneurysms in the elderly in Yamaguchi, Japan: analysis of the Yamaguchi Data Bank of cerebral aneurysm from 1985 to 1995. Stroke. 1998; 28: 1926–1933.
- ↵Sacco RL, Wolf PA, Bharucha NA, Meeks SL, Kannel WB, Charrette LJ, McNamara PM, Palmer EP. Subarachnoid and intracranial hemorrhage: natural history, prognosis, and precursive factors in the Framingham Study. Neurology. 1984; 34: 847–854.
- ↵Iwamoto H, Kiyohara Y, Fujishima M, Kato I, Nakayama K, Sueishi K, Tsuneyoshi M. Prevalence of intracranial aneurysms in a Japanese community based on a consecutive autopsy series during a 30-year observation period: the Hisayama study. Stroke. 1999; 30: 1390–1395.
- ↵Brilstra EH, Rinkel GJ, Van der Graaf Y, Van Rooij WJ, Algra A. Treatment of intracranial aneurysms by embolization with coils. Stroke. 1999; 30: 470–476.
- ↵Sawada M, Kaku Y, Hayashi K, Ueda T, Yoshimura S, Sakai N. Endovascular treatment of ruptured intracranial aneurysms using platinum coils in patients over 70 years of age. Intervent Neuroradiol. 2000; 6: 85–88.
- ↵Vollmer DG, Torner JC, Jane JA, Sadvonic B, Charlebios D, Eisenberg H, Foulkes M, Marmarou A, Marshall L. Age and outcome following traumatic coma: why do older patients fare worse? J Neurosurg. 1971; 75 (suppl): S37–S39.