Spontaneous Regression of a Symptomatic Intramedullary Spinal Cord Lesion

Intramedullary spinal cord tumors and cavernous malformations are rare lesions that can lead to progressive neurologic deficits, impaired quality of life, and even death. Early diagnosis and surgical resection of spinal cord tumors and cavernous malformations are often quoted as essential to optimizing a patient’s functional outcome. Unfortunately, these are high-risk operations, with many patients having worse neurological deficits after surgery - sometimes permanent.

We present a case of a patient with a cervical intramedullary spinal cord lesion that almost completely resolved spontaneously at short-term follow-up and remained stable at longe-term follow up. Conservative management with careful observation and sequential imaging should be considered in patients with intramedullary spinal cord lesions presenting with acute onset, stable symptoms, especially if the lesion has a hemorrhagic component.

Association of Intravitreal Anti-Vascular Endothelial Growth Factor Therapy With Risk of Stroke, Myocardial Infarction, and Death in Patients With Exudative Age-Related Macular Degeneration

Importance

Current studies assessing the risk of stroke, myocardial infarction (MI), and death in patients undergoing intravitreal anti-vascular endothelial growth factor (VEGF) therapy are inconclusive. To our knowledge, no population-based studies have been performed to examine these potential risks.

Objective

To examine whether patients with exudative age-related macular degeneration (AMD) receiving intravitreal anti-VEGF injections have a higher incidence of MI, stroke, or death compared with control populations.

Design, Setting, and Participants

This population-based, retrospective cohort study included 504 patients from Olmsted County, Minnesota, identified through the Rochester Epidemiology Project (REP) database as receiving at least 1 intravitreal anti-VEGF injection for exudative AMD from January 1, 2004, to December 31, 2013. Three age- and sex-matched control groups of individuals who did not receive anti-VEGF treatment and were derived from the REP database were also studied: control individuals with exudative AMD in the era before anti-VEGF (January 1, 1990, to December 31, 2003), controls with dry AMD, and controls without AMD. Data analysis was performed from September 1, 2016, to September 1, 2017.

Main Outcomes and Measures

Five-year risk of stroke, MI, and death were assessed in patients compared with controls using Kaplan-Meier and multivariate analysis with Cox proportional hazards regression models.

Results

The study included 504 patients (321 female [63.7%]; mean [SD] age, 76.5 [10.0] years) who received at least 1 intravitreal anti-VEGF injection for exudative AMD during the study period. Kaplan-Meier analysis revealed a 5-year risk of 7.2% for stroke, 6.1% for MI, and 30.0% for death. Patients who received anti-VEGF had no increased risk of stroke or MI compared with controls with dry AMD (n = 504), controls with exudative AMD (n = 473), or controls without AMD (n = 504). There was an increased risk of mortality compared with controls with exudative AMD in the era prior to anti-VEGF therapy but not the other control groups on multivariate analysis (hazard ratio, 1.63; 95% CI, 1.30-2.04; P < .001).

Conclusions and Relevance

This population-based study revealed that intravitreal anti-VEGF therapy for exudative AMD was not associated with consistent increases in the risk of stroke, MI, or death compared with no therapy in patients with or without AMD. It appears to be likely the cardiac events these patients experience are not attributable to their anti-VEGF therapy.

Classification of Strokes in Patients Receiving Intravitreal Anti-Vascular Endothelial Growth Factor

BACKGROUND AND OBJECTIVE

The purpose of this study was to identify the differences in the types of strokes seen in patients receiving intravitreal anti-vascular endothelial growth factor (VEGF) compared with normal control populations.

PATIENTS AND METHODS

We performed a retrospective consecutive review of all patients receiving intravitreal anti-VEGF injections in Olmsted County, Minnesota, from January 1, 2004, to December 31, 2013, for exudative age-related macular degeneration (AMD), diabetic macular edema (DME), proliferative diabetic retinopathy (PDR), or retinal vein occlusion (RVO). A 2-year follow-up period was required for study inclusion. Three age- and sex-matched cohorts were identified.

RESULTS

A total of 2,541 patients were examined. There were 690 patients identified during the study period as receiving an intravitreal injection for AMD, DME, PDR, or RVO. Of these patients, 38 (5.8%) suffered a stroke after starting intravitreal injection therapy. Of these strokes, 27 (71.1%) were ischemic, six (15.8%) were embolic, and five (13.2%) were hemorrhagic. There were no differences in the types of strokes identified among the patients receiving intravitreal injections between the case cohort and the control cohorts (P > .05 for all).

CONCLUSION

The authors' data suggest there is no predilection to the development of ischemic infarcts or hemorrhagic strokes in those patients receiving intravitreal anti-VEGF compared with control populations. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e140-e157.].

Aneurysm Morphology and Prediction of Rupture: An International Study of Unruptured Intracranial Aneurysms Analysis

BACKGROUND

There are conflicting data between natural history studies suggesting a very low risk of rupture for small, unruptured intracranial aneurysms and retrospective studies that have identified a much higher frequency of small, ruptured aneurysms than expected.

OBJECTIVE

To use the prospective International Study of Unruptured Intracranial Aneurysms cohort to identify morphological characteristics predictive of unruptured intracranial aneurysm rupture.

METHODS

A case-control design was used to analyze morphological characteristics associated with aneurysm rupture in the International Study of Unruptured Intracranial Aneurysms database. Fifty-seven patients with ruptured aneurysms during follow-up were matched (by size and location) with 198 patients with unruptured intracranial aneurysms without rupture during follow-up. Twelve morphological metrics were measured from cerebral angiograms in a blinded fashion.

RESULTS

Perpendicular height (P = .008) and size ratio (ratio of maximum diameter to the parent vessel diameter; P = .01) were predictors of aneurysm rupture on univariate analysis. Aspect ratio, daughter sacs, multiple lobes, aneurysm angle, neck diameter, parent vessel diameter, and calculated aneurysm volume were not statistically significant predictors of rupture. On multivariate analysis, perpendicular height was the only significant predictor of rupture (Chi-square 7.1, P-value .008).

CONCLUSION

This study underscores the importance of other morphological factors, such as perpendicular height and size ratio, that may influence unruptured intracranial aneurysm rupture risk in addition to greatest diameter and anterior vs posterior location.

Abstract 108: Long-Term Outcome of Giant Unruptured Intracranial Aneurysms

Introduction: Giant intracranial aneurysms are uncommon, have a high risk for rupture and are difficult to treat. The International Study of Unruptured Intracranial Aneurysms (ISUIA) prospective cohort included 187 patients with maximal diameter of 25 mm or greater. This analysis was to determine the long-term prognosis of these aneurysms both treated and untreated.

Methods: Patients were enrolled into ISUIA at 61 centers from 1991-1998. A prospective cohort included the managed with observation, surgery or endovascular treatment. Patients were followed for a median of 9.2 years. Aneurysms were measured using a central reading of bi-planar cerebral angiography. Outcomes were determined prospectively and with central review.

Results: 187 patients with a maximum diameter of 25 mm were followed. The mean size was 30.3 mm, ranging from 25 to 63 mm. 39% of the aneurysms were surgically treated at baseline, 27% were endovascularly treated, and 32% were managed conservatively;3% had subsequent endovascular treatment and 5% surgical treatment. Patients with giant aneurysms were predominantly women (83%), had a baseline Rankin Score of in 93%, were located predominantly in the anterior circulation (internal carotid 44%, cavernous ICA 28%, middle cerebral 12%). 80% of the patients were symptomatic with cranial nerve deficit in 47% (III and VI nerves), mass effect in 16%, headaches in 44%, orbital pain in 21%, and vision loss in 25%. Smoking history was present in 67%, hypertension in 44%, vascular headaches in 29% and family history in 10%. 70 patients (39%) died during follow-up however 59% were still Rankin 1 or 2. Both surgical and endovascular treated patients had 60-64% good outcome and 34-36% mortality. Untreated patients had a 57% mortality. Subarachnoid hemorrhage occurred in 11 untreated patients and 12 treated patients with most occurring in the first year.

Conclusions: Giant intracranial aneurysms are typically symptomatic, and have a high risk of rupture early after diagnosis. Outcome was similar with surgical and endovascular treatment but post-procedure hemorrhage did occur.

Affected twins in the familial intracranial aneurysm study

BACKGROUND AND PURPOSE

Very few cases of intracranial aneurysms (IAs) in twins have been reported. Previous work has suggested that vulnerability to IA formation is heritable. Twin studies provide an opportunity to evaluate the impact of genetics on IA characteristics, including IA location. We therefore sought to examine IA location concordance, multiplicity, and rupture status within affected twin-pairs.

METHODS

The Familial Intracranial Aneurysm study was a multicenter study whose goal was to identify genetic and other risk factors for formation and rupture of IAs. The study required at least three affected family members or an affected sibling pair for inclusion. Subjects with fusiform aneurysms, an IA associated with an AVM, or a family history of conditions known to predispose to IA formation, such as polycystic kidney disease, Ehlers-Danlos syndrome, Marfan syndrome, fibromuscular dysplasia, or moyamoya syndrome were excluded. Twin-pairs were identified by birth date and were classified as monozygotic (MZ) or dizygotic (DZ) through DNA marker genotypes. In addition to zygosity, we evaluated twin-pairs by smoking status, major arterial territory of IAs, and rupture status. Location concordance was defined as the presence of an IA in the same arterial distribution (ICA, MCA, ACA, and vertebrobasilar), irrespective of laterality, in both members of a twin-pair. The Fisher exact test was used for comparisons between MZ and DZ twin-pairs.

RESULTS

A total of 16 affected twin-pairs were identified. Location concordance was observed in 8 of 11 MZ twin-pairs but in only 1 of 5 DZ twin-pairs (p = 0.08). Three MZ subjects had unknown IA locations and comprised the three instances of MZ discordance. Six of the 11 MZ twin-pairs and none of the 5 DZ twin-pairs had IAs in the ICA distribution (p = 0.03). Multiple IAs were observed in 11 of 22 MZ and 5 of 10 DZ twin-pairs. Thirteen (13) of the 32 subjects had an IA rupture, including 10 of 22 MZ twins.

CONCLUSIONS

We found that arterial location concordance was greater in MZ than DZ twins, which suggests a genetic influence upon aneurysm location. The 16 twin-pairs in the present study are nearly the total of affected twin-pairs that have been reported in the literature to date. Further studies are needed to determine the impact of genetics in the formation and rupture of IAs.

Age-related differences in unruptured intracranial aneurysms: 1-year outcomes

Object

The aim of this study was to determine age-related differences in short-term (1-year) outcomes in patients with unruptured intracranial aneurysms (UIAs).

Methods

Four thousand fifty-nine patients prospectively enrolled in the International Study of Unruptured Intracranial Aneurysms were categorized into 3 groups by age at enrollment: < 50, 50–65, and > 65 years old. Outcomes assessed at 1 year included aneurysm rupture rates, combined morbidity and mortality from aneurysm procedure or hemorrhage, and all-cause mortality. Periprocedural morbidity, in-hospital morbidity, and poor neurological outcome on discharge (Rankin scale score of 3 or greater) were assessed in surgically and endovascularly treated groups. Univariate and multivariate associations of each outcome with age were tested.

Results

The risk of aneurysmal hemorrhage did not increase significantly with age. Procedural and in-hospital morbidity and mortality increased with age in patients treated with surgery, but remained relatively constant with increasing age with endovascular treatment. Poor neurological outcome from aneurysm- or procedure-related morbidity and mortality did not differ between management groups for patients 65 years old and younger, but was significantly higher in the surgical group for patients older than 65 years: 19.0% (95% confidence interval [CI] 13.9%–24.4%), compared with 8.0% (95% CI 2.3%–13.6%) in the endovascular group and 4.2% (95% CI 2.3%–6.2%) in the observation group. All-cause mortality increased steadily with increasing age, but differed between treatment groups only in patients < 50 years of age, with the surgical group showing a survival advantage at 1 year.

Conclusions

Surgical treatment of UIAs appears to be safe, prevents 1-year hemorrhage, and may confer a survival benefit in patients < 50 years of age. However, surgery poses a significant risk of morbidity and death in patients > 65 years of age. Risk of endovascular treatment does not appear to increase with age. Risks and benefits of treatment in older patients should be carefully considered, and if treatment is deemed necessary for patients older than 65 years, endovascular treatment may be the best option.

Genome-wide association study of intracranial aneurysm identifies a new association on chromosome 7

BACKGROUND AND PURPOSE

Common variants have been identified using genome-wide association studies which contribute to intracranial aneurysms (IA) susceptibility. However, it is clear that the variants identified to date do not account for the estimated genetic contribution to disease risk.

METHODS

Initial analysis was performed in a discovery sample of 2617 IA cases and 2548 controls of white ancestry. Novel chromosomal regions meeting genome-wide significance were further tested for association in 2 independent replication samples: Dutch (717 cases; 3004 controls) and Finnish (799 cases; 2317 controls). A meta-analysis was performed to combine the results from the 3 studies for key chromosomal regions of interest.

RESULTS

Genome-wide evidence of association was detected in the discovery sample on chromosome 9 (CDKN2BAS; rs10733376: P<1.0×10(-11)), in a gene previously associated with IA. A novel region on chromosome 7, near HDAC9, was associated with IA (rs10230207; P=4.14×10(-8)). This association replicated in the Dutch sample (P=0.01) but failed to show association in the Finnish sample (P=0.25). Meta-analysis results of the 3 cohorts reached statistical significant (P=9.91×10(-10)).

CONCLUSIONS

We detected a novel region associated with IA susceptibility that was replicated in an independent Dutch sample. This region on chromosome 7 has been previously associated with ischemic stroke and the large vessel stroke occlusive subtype (including HDAC9), suggesting a possible genetic link between this stroke subtype and IA.

Aneurysm shape reconstruction from biplane angiograms in the ISUIA collection

The International Study of Unruptured Intracranial Aneurysms (ISUIA) is an epidemiologic international study of the natural history of unruptured intracranial aneurysms that enrolled 4,060 subjects. A conventional biplane cerebral angiogram available for central review was required for enrollment resulting in a large database. Data on aneurysms that ruptured during follow-up of the 1,692 untreated subjects provides an opportunity to investigate the anatomic features that may be predictive of future rupture. The objective of the study is to develop and test a method for three-dimensional (3D) shape reconstruction of aneurysms using biplane angiographic data in the ISUIA for retrospective morphometric assessment. Beginning with the two boundaries of the biplane views, curve morphing techniques were employed to estimate a number of intermediate boundaries around the aneurysm sac resulting in the creation of a 3D sac surface. The method was tested using simulated biplane "angiograms" of pre-reconstructed 3D models of patient-specific aneurysms. An algorithm to perform the image analysis was developed, and the morphometric indices of 150 intracranial aneurysms in the ISUIA database were estimated. Simultaneously, experienced neuroradiologists made manual measurements of key dimensions in the sac from the biplane angiograms for all cases. 3D reconstructions using our proposed method matched well with the original pre-reconstructed 3D geometries and were consistent with manual measurements of the neuroradiologists for the ISUIA aneurysms. A method for reconstructing the 3D geometry of the intracranial aneurysm sac from biplane angiograms in the ISUIA database with reasonable fidelity has been developed.

The durability of carotid endarterectomy: long-term results for restenosis and stroke

BACKGROUND

Carotid endarterectomy is a low-risk treatment for carotid occlusive disease. Recent clinical trials have suggested that carotid angioplasty may be a viable alternative. One important issue that has not been evaluated is the long-term recurrent stenosis rate after either intervention.

OBJECTIVE

To examine the risk of recurrent stenosis after carotid endarterectomy and to provide long-term data on the durability of carotid endarterectomy.

METHODS

A total of 1335 sequential patients were followed up prospectively with annual carotid ultrasonography. All patients were maintained on antiplatelet therapy, and arteriotomies were closed with a patch graft. Operations were performed under general anesthesia with electroencephalographic monitoring and selective shunting. There were no changes in surgical technique during this study.

RESULTS

Two-thirds of the patients were men; the mean age was 70 years. Approximately 60% were symptomatic. The 90-day perioperative morbidity and mortality rate was 0.9% (0.4% stroke and 0.5% death). Five patients (0.4%) developed recurrent stenosis >70% over a mean follow-up of 15.8 years. Twelve patients (0.9%) had documentation of late stroke in the ipsilateral carotid distribution. The mean follow-up was 15.8 years.

CONCLUSION

Carotid endarterectomy is an extremely safe treatment for carotid stenosis with very low perioperative complications and low rates of recurrent stenosis or late stroke. When endarterectomy is compared with angioplasty, in addition to periprocedural complications, the durability of both interventions needs to be considered, given the risks and costs of repeat interventions.

Abstract 242: Long-term Outcome Of Quality Of Life Related To Treatment And Observation In Unruptured Intracranial Aneurysms

Introduction: Quality of life changes can occur following procedural interventions and subarachnoid hemorrhage in unruptured intracranial aneurysms (UIA). The International Study of Unruptured Intracranial Aneurysms conducted quality of life assessment using the Mini-Mental State Exam, Rankin Score, and Barthel Index at baseline and the Telephone Interview Cognitive Status Exam (TICS), Rankin Score, and Barthel Index at follow-up.

Hypothesis: The purpose of this analysis was to compare the 1 year and 5 year outcome in the treatment cohorts (surgery and endovascular) with those of the untreated subgroup.

Methods: Patients were subdivided into the initial treated and untreated cohorts based upon observation or treatment practices in 61 centers from 1991-1998. 1691 patients were in the observational cohort and 2388 in the treated cohort. The cohorts were followed annually with measures of neurological status, Rankin Scale, Barthel Index and cognition (TICS). Outcomes were determined prospectively. Comparison of outcomes was done using continuous and categorical data. Covariate adjustment was done using general linear models. Stratified analysis was done by Rankin Score at the time of follow-up.

Results: The percent of patients with a Barthel Index score of less than 60 at 1 year in the cohort was 9.4% (treated patients, 9.7%; untreated patients, 9.2%). The percent of patients at year 1 with a score of greater than 90 was 87.6%, 87.4% for treated patients and 87.8% for untreated patients. The percent of patients with a Barthel Index score of less than 60 at 5 years in the cohort was 41.4% (treated patients, 41.4%; untreated patients, 41.4%). The percent of patients at year 5 with a score of greater than 90 was 56.3%, 56.1% for treated patients and 56.5% for untreated patients.

TICS and Barthel Index scores were significantly associated with each other for patients with Rankin Scores 0-2 (P<0.0001). This was seen at both year 1 and year 5 follow-up, but not for patients with Rankin Score 3-5. At both 1 year and 5 year follow-up, after controlling for Rankin Score, the distribution of Barthel Index scores of untreated patients and treated patients did not significantly differ. At both the 1 year follow-up, baseline Rankin Score, TICS and follow-up Rankin Score were significant predictors of Barthel Score (P<0.0001). At 5 years, only the follow-up Rankin Score was associated with Barthel Score (P<0.0001).

Conclusions: Barthel Index Score decreased over time, but does not differ with treatment. The Rankin Score was the main predictor at follow-up of Barthel Index Score distribution.

Abstract WP79: Choice Of Treatment And Effect On Hemorrhage Rates Of Unruptured Intracranial Aneurysms

INTRODUCTION: The decision regarding whether to perform an interventional procedure as a strategy to prevent hemorrhage of an unruptured intracranial aneurysm (UIA) requires careful consideration of procedural risk and the UIA natural history. No randomized trial data are available. The International Study of Unruptured Intracranial Aneurysms (ISUIA) included a prospective cohort, examining hemorrhage risk and treatment risk.

Hypothesis: The purpose of this analysis was to compare the factors related to treatment selection and determination of the number of hemorrhages prevented.

Methods: Patients were allocated into the initial treatment and untreated cohorts based upon observation or treatment practices in 61 centers from 1991-1998. 1691 patients were in the observational cohort, 471 were in the endovascular cohort and 1917 patients were in the surgical cohort. The cohorts were followed for a median follow-up of 9.2 years. Outcomes were determined prospectively and with central review. The data were grouped together and analyzed to determine treatment decisions. A Cox proportional hazards model predicting hemorrhage developed in the observation cohort and was applied to the surgery and endovascular cohorts across the follow-up period.

Results: Significant baseline variable differences between treated and observed patients were aneurysm size, symptoms, age, prior SAH group, geographical region, treatment percentage, aneurysm daughter sacs or multiple lobes, and history of hypertension, smoking and myocardial infarction. Aneurysm site and family history were not significant. Site, size, and aspirin use were significant predictors of hemorrhage.

Long-term the predicted hemorrhage rates were 6.7% at 5 years and 8.0% at 10 years in the surgery group and 8.1% and 9.6% for the endovascular group, respectively. For comparison the rates in the observed cohort were 4.1% and 4.8%, respectively.

Conclusions: Decisions for treatment are influenced by patient characteristics such as age and medical history, aneurysm characteristics such as size and morphology and center and regional practices. Patients in the treated cohorts were at moderately increased risk for hemorrhage compared to those in the observed cohort.

Abstract WP74: Long-term Outcome Of Cognition Related To Treatment And Observation In Unruptured Intracranial Aneurysms

INTRODUCTION: Cognitive changes can occur following procedural interventions and subarachnoid hemorrhage in unruptured intracranial aneurysms (UIA). The International Study of Unruptured Intracranial Aneurysms conducted cognitive assessment using the Mini-Mental State Exam at baseline and the Telephone Interview Cognitive Status Exam (TICS) at follow-up.

Hypothesis: The purpose of this analysis was to compare the 1 year and 5 year outcome in the treatment cohorts (surgery and endovascular) with those of the untreated subgroup.

Methods: Patients were subdivided into the initial treatment and untreated cohorts based upon observation or treatment practices in 61 centers from 1991-1998. 1691 patients were in the observational cohort and 2388 in the treated cohort. The cohorts were followed annually with measures of neurological status, Rankin Scale and cognition (TICS). Outcomes were determined prospectively. Comparison of outcomes was done using continuous data and by categories. Covariate adjustment was done using general linear models. Stratified analysis was done by Rankin Score at the time of follow-up.

Results: The mean TICS score at 1 year in the cohort was 33.4 with a median of 34 (maximum is 40). In the treated patients the mean was 33.5 and in the untreated patients it was 33.3 (P=0.644). However, Rankin Score at 1 year was significant with a higher percentage of 3-5 scores in the treated group (P=0.003) Categorical analysis of the TICS Score when stratified by Rankin Score at 1 year showed small but significant differences, P=0.03 for Rankin 0-2, and P=0.07 for Rankin 3-5. However after adjustment for baseline variables treatment TICS Score was no longer significant.. The 5 year results showed that the untreated patients did worse than the treated group in TICS. However after adjustment no differences were apparent.

Conclusions: Cognitive changes associated with treatment may be minor source of disability post-treatment compared to observation and patient outcomes may be worse in the observation group over time. Differences in outcome also were better explained through the Rankin Score at follow-up than by cognitive deficits.

Abstract TMP27: Aneurysm Morphology And Prediction Of Rupture In Unruptured Intracranial Aneurysms

Introduction: There is ongoing debate regarding the rupture risk of an unruptured intracranial aneurysm (UIA), and the predictors of rupture.

Hypothesis: There are aneurysm morphology characteristics which predict rupture in patients with an UIA. The purpose of this analysis was to assess for such characteristics utilizing the International Study of Unruptured Intracranial Aneurysms (ISUIA) cohort.

Methods: Patients were entered prospectively at 61 centers. Patients must have had at least one UIA, which may or may not have been symptomatic. Patients were followed for a median of 9 years and all potential hemorrhages were carefully adjudicated. A case-control design was used. The cases were 57 patients with aneurysmal rupture during followup for whom detailed radiology data were available from arteriography. Controls were 198 size- (+/- 2 mm maximum diameter) and location- (parent artery) matched patients without rupture during followup. Numerous aneurysm morphology characteristics were assessed on arteriogram review. Multivariable condition logistic regression modeling was performed.

Results: A total of 57 cases and 198 controls were included. Most (76%) of the 255 cases were women, and 20% had a prior history of SAH from some other aneurysm. There were no differences between cases and controls in aneurysm maximum diameter, aneurysm location, patient age, gender, reason for presentation, or prior medical history. Multivariate analysis identified that only perpendicular height of the aneurysm--the measurement of the aneurysm height at a perpendicular to the center of the aneurysm neck to the aneurysm dome-was an independent predictor of aneurysm rupture. Aspect ratio, size ratio, parent vessel diameter, presence of daughter sac, and aneurysm angle were not independent predictors of rupture.

Conclusions: After controlling for aneurysm size and location, the aneurysm perpendicular height remained a predictor of UIA rupture during long-term followup. The assessment of perpendicular height may be helpful in clinical practice, in addition to the other key predictors of UIA rupture, aneurysm maximum diameter and location. Further investigation into the use of perpendicular height as a predictor of rupture in patients with UIA is indicated.

Familial intracranial aneurysms: is anatomic vulnerability heritable?

BACKGROUND AND PURPOSE

Previous studies have suggested that family members with intracranial aneurysms (IAs) often harbor IAs in similar anatomic locations. IA location is important because of its association with rupture. We tested the hypothesis that anatomic susceptibility to IA location exists using a family-based IA study.

METHODS

We identified all affected probands and first-degree relatives (FDRs) with a definite or probable phenotype in each family. We stratified each IA of the probands by major arterial territory and calculated each family's proband-FDR territory concordance and overall contribution to the concordance analysis. We then matched each family unit to an unrelated family unit selected randomly with replacement and performed 1001 simulations. The median concordance proportions, odds ratios (ORs), and P values from the 1001 logistic regression analyses were used to represent the final results of the analysis.

RESULTS

There were 323 family units available for analysis, including 323 probands and 448 FDRs, with a total of 1176 IAs. IA territorial concordance was higher in the internal carotid artery (55.4% versus 45.6%; OR, 1.54 [1.04-2.27]; P=0.032), middle cerebral artery (45.8% versus 30.5%; OR, 1.99 [1.22-3.22]; P=0.006), and vertebrobasilar system (26.6% versus 11.3%; OR, 2.90 [1.05-8.24], P=0.04) distributions in the true family compared with the comparison family. Concordance was also higher when any location was considered (53.0% versus 40.7%; OR, 1.82 [1.34-2.46]; P<0.001).

CONCLUSIONS

In a highly enriched sample with familial predisposition to IA development, we found that IA territorial concordance was higher when probands were compared with their own affected FDRs than with comparison FDRs, which suggests that anatomic vulnerability to IA formation exists. Future studies of IA genetics should consider stratifying cases by IA location.

Genome-wide association study of intracranial aneurysms confirms role of Anril and SOX17 in disease risk

BACKGROUND

Genomewide association studies have identified novel genetic factors that contribute to intracranial aneurysm (IA) susceptibility. We sought to confirm previously reported loci, to identify novel risk factors, and to evaluate the contribution of these factors to familial and sporadic IA.

METHOD

We utilized 2 complementary samples, one recruited on the basis of a dense family history of IA (discovery sample 1: 388 IA cases and 397 controls) and the other without regard to family history (discovery sample 2: 1095 IA cases and 1286 controls). Imputation was used to generate a common set of single nucleotide polymorphisms (SNP) across samples, and a logistic regression model was used to test for association in each sample. Results from each sample were then combined in a metaanalysis.

RESULTS

There was only modest overlap in the association results obtained in the 2 samples. In neither sample did results reach genomewide significance. However, the metaanalysis yielded genomewide significance for SNP on chromosome 9p (CDKN2BAS; rs6475606; P=3.6×10(-8)) and provided further evidence to support the previously reported association of IA with SNP in SOX17 on chromosome 8q (rs1072737; P=8.7×10(-5)). Analyses suggest that the effect of smoking acts multiplicatively with the SNP genotype, and smoking has a greater effect on risk than SNP genotype.

CONCLUSIONS

In addition to replicating several previously reported loci, we provide further evidence that the association on chromosome 9p is attributable to variants in CDKN2BAS (also known as ANRIL, an antisense noncoding RNA).

Unruptured intracranial aneurysms in the Familial Intracranial Aneurysm and International Study of Unruptured Intracranial Aneurysms cohorts: differences in multiplicity and location

OBJECT

Familial predisposition is a recognized nonmodifiable risk factor for the formation and rupture of intracranial aneurysms (IAs). However, data regarding the characteristics of familial IAs are limited. The authors sought to describe familial IAs more fully, and to compare their characteristics with a large cohort of nonfamilial IAs.

METHODS

The Familial Intracranial Aneurysm (FIA) study is a multicenter international study with the goal of identifying genetic and other risk factors for formation and rupture of IAs in a highly enriched population. The authors compared the FIA study cohort with the International Study of Unruptured Intracranial Aneurysms (ISUIA) cohort with regard to patient demographic data, IA location, and IA multiplicity. To improve comparability, all patients in the ISUIA who had a family history of IAs or subarachnoid hemorrhage were excluded, as well as all patients in both cohorts who had a ruptured IA prior to study entry.

RESULTS

Of 983 patients enrolled in the FIA study with definite or probable IAs, 511 met the inclusion criteria for this analysis. Of the 4059 patients in the ISUIA study, 983 had a previous IA rupture and 657 of the remainder had a positive family history, leaving 2419 individuals in the analysis. Multiplicity was more common in the FIA patients (35.6% vs 27.9%, p<0.001). The FIA patients had a higher proportion of IAs located in the middle cerebral artery (28.6% vs 24.9%), whereas ISUIA patients had a higher proportion of posterior communicating artery IAs (13.7% vs 8.2%, p=0.016).

CONCLUSIONS

Heritable structural vulnerability may account for differences in IA multiplicity and location. Important investigations into the underlying genetic mechanisms of IA formation are ongoing.

Clinical features and racial/ethnic differences among the 3020 participants in the Secondary Prevention of Small Subcortical Strokes (SPS3) trial

This study examined the baseline characteristics, racial/ethnic differences, and geographic differences among participants in the Secondary Prevention of Small Subcortical Strokes (SPS3) study. The SPS3 trial enrolled patients who experienced a symptomatic small subcortical stroke (lacunar stroke) within the previous 6 months and an eligible lesion on detected on magnetic resonance imaging. The patients were randomized, in a factorial design, to antiplatelet therapy (aspirin 325 mg daily plus clopidogrel 75 mg daily vs aspirin 325 mg daily plus placebo) and to one of two levels of systolic blood pressure targets ("intensive" [<130 mmHg] or "usual" [130-149 mmHg]). A total of 3020 participants were recruited from 81 clinical sites in 8 countries. In this cohort, the mean age was 63 years, 63% were men, 75% had a history of hypertension, and 37% had diabetes. The racial distribution was 51% white, 30% Hispanic, and 16% black. Compared with white subjects, black subjects were younger (mean age, 58 years vs 64 years; P <.001) and had a higher prevalence of hypertension (87% vs 70%; P <.001). The prevalence of diabetes was higher in the Hispanic and black subjects compared with the white subjects (42% and 40% vs 32%; both P <.001). Tobacco smoking at the time of qualifying stroke was much more frequent in the Spanish participants than in subjects from North America and from Latin America (32%, 22%, and 9%, respectively; P <.001). Mean systolic blood pressure at study entry was 4 mmHg lower in the Spanish subjects compared with the North American subjects (P <.01). The SPS3 cohort is the largest magnetic resonance imaging-defined series of patients with S3. Among the racially/ethnically diverse SPS3 participants, important differences in patient features and vascular risk factors could influence prognosis for recurrent stroke and response to interventions.

Mirror aneurysms: a reflection on natural history

OBJECT

Investigators conducting the International Study of Unruptured Intracranial Aneurysms, sponsored by the National Institutes of Health, sought to evaluate predictors of future hemorrhage in patients who had unruptured mirror aneurysms. These paired aneurysms in bilateral arterial positions mirror each other; their natural history is unknown.

METHODS

Centers in the US, Canada, and Europe enrolled patients for prospective assessment of unruptured intracranial aneurysms. Central radiological review confirmed the presence or absence of mirror aneurysms in patients without a history of prior subarachnoid hemorrhage (SAH) (Group 1). Outcome at 1 and 5 years and aneurysm characteristics are compared.

RESULTS

Of 3120 patients with aneurysms treated in 61 centers, 376 (12%) had mirror aneurysms, which are more common in women than men (82% [n = 308] vs 73% [n = 1992], respectively; p <0.001) and in patients with a family history of aneurysm or SAH (p <0.001). Compared with patients with nonmirror saccular aneurysms, a greater percentage of patients with mirror aneurysms had larger (>10 mm) aneurysms (mean maximum diameter 11.7 vs 10.4 mm, respectively; p <0.001). The most common distribution for mirror aneurysms was the middle cerebral artery (34% [126 patients]) followed by noncavernous internal carotid artery (32% [121]), posterior communicating artery (16% [60]), cavernous internal carotid artery (13% [48]), anterior cerebral artery/anterior communicating artery (3% [13]), and vertebrobasilar circulation (2% [8]). When these patients were compared with patients without mirror aneurysms, no statistically significant differences were found in age (mean age 54 years in both groups), blood pressure, smoking history, or cardiac disease. Aneurysm rupture rates were similar (3.0% for patients with mirror aneurysms vs 2.8% for those without).

CONCLUSIONS

Overall, patients with mirror aneurysms were more likely to be women, to report a family history of aneurysmal SAH, and to have larger aneurysms. The presence of a mirror aneurysm was not an independent predictor of future SAHs.

Abstract 3906: Comparative Effectiveness of Long-Term Outcomes of Treatment of Unruptured Intracranial Aneurysms

Introduction: The long term effectiveness of preventive intracranial treatment of unruptured aneurysms for hemorrhage and aneurysm-related morbidity and mortality has been hypothesized. No randomized trial has been done. Propensity adjusted comparison within The International Study of Unruptured Intracranial Aneurysms was undertaken to compare long-term effectiveness.

Hypothesis: The purpose of this analysis was to compare the long-term outcome in the treatment cohorts (surgery and endovascular) with those of the untreated subgroup.

Methods: Patients were subdivided into the initial treatment and untreated cohorts based upon observation or treatment practices in 61 centers from 1991-1998. 1691 patients were in the observational cohort, 471 were in the endovascular cohort and 1917 patients were in the surgical cohort. The cohorts were followed for a median follow-up of 9.2 years. Outcomes were determined prospectively and with central review. The data were grouped together and analyzed to determine treatment decisions. Comparison of outcomes was done using covariate adjustment and using propensity analysis where equivalent probability groups were constructed. Similar main predictors of treatment and outcome were observed. Analysis of hemorrhage, mortality and short-term and long-term morbidity and mortality were assessed. Risk-benefit ratios were also calculated.

Results: Significant differences in baseline variables between treatment and observed patients were aneurysm size, symptoms, age, prior SAH or not group, geographical region, family history, hypertension and myocardial infarction history. The results show comparability of groups using the patient propensity-based score subset. Using the propensity score method, the results showed a benefit in prevention of hemorrhage by surgery and endovascular treatment versus observation (p<.01). No difference was found between endovascular versus surgery. However when procedure-related outcomes are included, no significant difference at 1 year, 5 years or 10 years in the combined aneurysm or procedure related endpoint was evident between cohorts.

Conclusions: Propensity score matching to achieve comparability resulted in balanced groups. Comparison of long-term results showed that intervention demonstrated a benefit in reducing hemorrhage risk. However, peri-procedural risk negates any short-term benefit for 10 years.

Abstract 3694: Competing Risk for Long-Term Mortality in Patients with Unruptured Intracranial Aneurysm

Introduction: Mortality in patients with unruptured intracranial aneurysm (UIA) is significantly higher than the general population. However a minority of the deaths are due to subarachnoid hemorrhage.

Hypothesis: There are differential characteristics of patients that might predict specific causes of death that would be informative in counseling patients about aneurysm risk.

Methods: 4059 patients with UIA who were enrolled prospectively between 1991 and 1998 were followed by 61 medical centers in North America, Canada, and Europe. Patients have at least one UIA, which may or may not be symptomatic. Patients were Rankin grade 1 or 2 at enrollment. Patients were followed annually from enrollment to 2007. For patients who died a death certificate search was done and information was requested from local physicians and other contacts. A National Death Index search in 2008 determined cases who died and cause of death. Foreign centers also did a national search where possible. Patients who died before 30 days post treatment or lost to follow up before 30 days post enrollment were excluded.

Results: Twenty-five percent of patients died during follow-up. The life expectancy was significantly less than age-, sex-, and country-matched expected estimates. Among the total of 4004 patients with UIA who survived 30 days after enrollment, 2331 were treated and 1673 were not. There were 965 deaths after 30 days after treatment, of which 320 died from vascular disease (252 died from non-SAH vascular disease), 114 died from respiratory tract disease, 255 died from cancer, and the rest died of other or unknown reasons. Predictors of SAH death were aneurysm size, site, age and convulsive disorders at enrollment. Factors related to vascular death were UIA treatment, age, gender, race, hypertension, Rankin at discharge and diminishing influence of aneurysm characteristics over time. Respiratory deaths were related to treatment, race, smoking, age, initial Rankin and presentation with convulsive disorder. Cancer deaths were related to gender, race, smoking and age.

Conclusions: In patients with UIA, an assessment of risk for death underscores the importance of age, race and gender and several modifiable risk factors. Patient management should include not only aneurysm rupture prevention but also modification of smoking and hypertension.

Aspirin as a promising agent for decreasing incidence of cerebral aneurysm rupture

BACKGROUND AND PURPOSE

Chronic inflammation is postulated as an important phenomenon in intracranial aneurysm wall pathophysiology. This study was conducted to determine if aspirin use impacts the occurrence of intracranial aneurysm rupture.

METHODS

Subjects enrolled in the International Study of Unruptured Intracranial Aneurysms (ISUIA) were selected from the prospective untreated cohort (n=1691) in a nested case-control study. Cases were subjects who subsequently had a proven aneurysmal subarachnoid hemorrhage during a 5-year follow-up period. Four control subjects were matched to each case by site and size of aneurysm (58 cases, 213 control subjects). Frequency of aspirin use was determined at baseline interview. Aspirin frequency groups were analyzed for risk of aneurysmal hemorrhage. Bivariable and multivariable analyses were performed using conditional logistic regression.

RESULTS

A trend of a protective effect for risk of unruptured intracranial aneurysm rupture was observed. Patients who used aspirin 3× weekly to daily had an OR for hemorrhage of 0.40 (95% CI, 0.18-0.87); reference group, no use of aspirin), patients in the "< once a month" group had an OR of 0.80 (95% CI, 0.31-2.05), and patients in the "> once a month to 2×/week" group had an OR of 0.87 (95% CI, 0.27-2.81; P=0.025). In multivariable risk factor analyses, patients who used aspirin 3 times weekly to daily had a significantly lower odds of hemorrhage (adjusted OR, 0.27; 95% CI, 0.11-0.67; P=0.03) compared with those who never take aspirin.

CONCLUSIONS

Frequent aspirin use may confer a protective effect for risk of intracranial aneurysm rupture. Future investigation in animal models and clinical studies is needed.

The relationship between smoking and replicated sequence variants on chromosomes 8 and 9 with familial intracranial aneurysm

BACKGROUND AND PURPOSE

The purpose of this study was to replicate the previous association of single nucleotide polymorphisms (SNPs) with risk of intracranial aneurysm (IA) and to examine the relationship of smoking with these variants and the risk of IA.

METHODS

White probands with an IA from families with multiple affected members were identified by 26 clinical centers located throughout North America, New Zealand, and Australia. White control subjects free of stroke and IA were selected by random digit dialing from the Greater Cincinnati population. SNPs previously associated with IA on chromosomes 2, 8, and 9 were genotyped using a TaqMan assay or were included in the Affymetrix 6.0 array that was part of a genomewide association study of 406 IA cases and 392 control subjects. Logistic regression modeling tested whether the association of replicated SNPs with IA was modulated by smoking.

RESULTS

The strongest evidence of association with IA was found with the 8q SNP rs10958409 (genotypic P=9.2x10(-5); allelic P=1.3x10(-5); OR=1.86, 95% CI: 1.40 to 2.47). We also replicated the association with both SNPs on chromosome 9p, rs1333040 and rs10757278, but were not able to replicate the previously reported association of the 2 SNPs on chromosome 2q. Statistical testing showed a multiplicative relationship between the risk alleles and smoking with regard to the risk of IA.

CONCLUSIONS

Our data provide complementary evidence that the variants on chromosomes 8q and 9p are associated with IA and that the risk of IA in patients with these variants is greatly increased with cigarette smoking.

Age at intracranial aneurysm rupture among generations: Familial Intracranial Aneurysm Study

BACKGROUND

Previous studies have reported intracranial aneurysm (IA) occurring at young ages in subsequent generations. These studies did not correct for duration of follow-up. Second-generation members who would have their ruptured IA late in life may not be detected due to shorter follow-up time than the first generation. We examined families in which ruptured IA occurred in two consecutive generations for the hypothesis that the second generation (F1) was more likely to have a rupture at a younger age than the older generation (F0).

METHODS

The Familial Intracranial Aneurysm (FIA) Study is a multicenter, international study recruiting families of ruptured and unruptured IA. All available family members are interviewed. Cox proportional hazards regression models and Kaplan-Meier curves were used to examine differences by generation.

RESULTS

Although we found that the F1 generation was more likely to have an aneurysm rupture at a younger age than the F0 generation, we found that this was largely because of a lack of follow-up time in the F1 generation. The F1 generation had 50% the rupture rate of the prior generation. When analyzed by Kaplan-Meier curves, we found a tendency to have a slightly later rupture rate in the F1 generation once time to follow-up was included in the analysis model.

CONCLUSIONS

Families of ruptured intracranial aneurysm (IA) do not appear to demonstrate "anticipation." Our finding suggests that genetic epidemiology of ruptured IA should examine all types of variations such as single base-pair changes, deletions, insertions, and other variations that do not demonstrate anticipation.

Greater rupture risk for familial as compared to sporadic unruptured intracranial aneurysms

BACKGROUND AND PURPOSE

The risk of intracranial aneurysm (IA) rupture in asymptomatic members of families who have multiple affected individuals is not known.

METHODS

First-degree unaffected relatives of those with a familial history of IA who had a history of smoking or hypertension but no known IA were offered cerebral MR angiography (MRA) and followed yearly as part of a National Institute of Neurological Diseases and Stroke-funded study of familial IA (Familial Intracranial Aneurysm [FIA] Study).

RESULTS

A total of 2874 subjects from 542 FIA Study families were enrolled. After study enrollment, MRAs were performed in 548 FIA Study family members with no known history of IA. Of these 548 subjects, 113 subjects (20.6%) had 148 IAs by MRA of whom 5 subjects had IA >or=7 mm. Two subjects with an unruptured IA by MRA/CT angiography (3-mm and 4-mm anterior communicating artery) subsequently had rupture of their IA. This represents an annual rate of 1.2 ruptures per 100 subjects (1.2% per year; 95% CI, 0.14% to 4.3% per year). None of the 435 subjects with a negative MRA have had a ruptured IA. Survival curves between the MRA-positive and -negative cohorts were significantly different (P=0.004). This rupture rate of unruptured IA in the FIA Study cohort of 1.2% per year is approximately 17 times higher than the rupture rate for subjects with an unruptured IA in the International Study of Unruptured Aneurysm Study with a matched distribution of IA size and location 0.069% per year.

CONCLUSIONS

Small unruptured IAs in patients from FIA Study families may have a higher risk of rupture than sporadic unruptured IAs of similar size, which should be considered in the management of these patients.

Genome screen in familial intracranial aneurysm

Background

Individuals with 1st degree relatives harboring an intracranial aneurysm (IA) are at an increased risk of IA, suggesting genetic variation is an important risk factor.

Methods

Families with multiple members having ruptured or unruptured IA were recruited and all available medical records and imaging data were reviewed to classify possible IA subjects as definite, probable or possible IA or not a case. A 6 K SNP genome screen was performed in 333 families, representing the largest linkage study of IA reported to date. A 'narrow' (n = 705 definite IA cases) and 'broad' (n = 866 definite or probable IA) disease definition were used in multipoint model-free linkage analysis and parametric linkage analysis, maximizing disease parameters. Ordered subset analysis (OSA) was used to detect gene × smoking interaction.

Results

Model-free linkage analyses detected modest evidence of possible linkage (all LOD < 1.5). Parametric analyses yielded an unadjusted LOD score of 2.6 on chromosome 4q (162 cM) and 3.1 on chromosome 12p (50 cM). Significant evidence for a gene × smoking interaction was detected using both disease models on chromosome 7p (60 cM; p ≤ 0.01). Our study provides modest evidence of possible linkage to several chromosomes.

Conclusion

These data suggest it is unlikely that there is a single common variant with a strong effect in the majority of the IA families. Rather, it is likely that multiple genetic and environmental risk factors contribute to the susceptibility for intracranial aneurysms.

Increased left atrial volume index: potent biomarker for first-ever ischemic stroke

OBJECTIVE

To establish the incidence and correlation of increased left atrial volume index (LAVI) in patients with first-ever ischemic stroke.

PARTICIPANTS AND METHODS

Using our institution's epidemiological database, we defined a cohort of 432 patients (cases) who underwent transthoracic echocardiography within 60 days of first ischemic stroke between January 1, 1985, and December 31, 1994. Left atrial volume was measured with the biplane area-length method, indexed to body surface area (LAVI, expressed as mL/m(2)). The control group consisted of 416 community residents who underwent transthoracic echocardiography as participants in a stroke risk factor study. Increased LAVI was defined as 28 mL/m(2) or higher. Survival in patients was compared with expected survival among white Minnesotans and was further modeled as a function of age, sex, LAVI, and clinical risk factors.

RESULTS

Among the included 306 patients, 230 (75%) had increased LAVI (mean+/-SD, 49+/-21 mL/m(2)). Patients with increased LAVI were older than those with normal LAVI (mean+/-SD age, 76+/-11 vs 71+/-13 years; P=.003) and had more cardiovascular risk factors (mean+/-SD number, 1.8+/-0.07 vs 1.3+/-0.89; P<.001). Mean LAVI was higher in cases than in age- and sex-matched controls (P<.001). At 5-year follow-up, cases showed excess mortality compared with age-matched controls (P=.001). After variables were adjusted for age, sex, and clinical risk factors, LAVI was independently associated with mortality.

CONCLUSION

A useful index for prediction of adverse cardiovascular events, LAVI might also predict first ischemic stroke and subsequent mortality.

Screening for brain aneurysm in the Familial Intracranial Aneurysm study: frequency and predictors of lesion detection

OBJECT

Approximately 20% of patients with an intracranial saccular aneurysm report a family history of intracranial aneurysm (IA) or subarachnoid hemorrhage. A better understanding of predictors of aneurysm detection in familial IA may allow more targeted aneurysm screening strategies.

METHODS

The Familial Intracranial Aneurysm (FIA) study is a multicenter study, in which the primary objective is to define the susceptibility genes related to the formation of IA. First-degree relatives (FDRs) of those affected with IA are offered screening with magnetic resonance (MR) angiography if they were previously unaffected, are > or = 30 years of age, and have a history of smoking and/or hypertension. Independent predictors of aneurysm detection on MR angiography were determined using the generalized estimating equation version of logistic regression.

RESULTS

Among the first 303 patients screened with MR angiography, 58 (19.1%) had at least 1 IA, including 24% of women and 11.7% of men. Ten (17.2%) of 58 affected patients had multiple aneurysms. Independent predictors of aneurysm detection included female sex (odds ratio [OR] 2.46, p = 0.001), pack-years of cigarette smoking (OR 3.24 for 20 pack-years of cigarette smoking compared with never having smoked, p < 0.001), and duration of hypertension (OR 1.26 comparing those with 10 years of hypertension to those with no hypertension, p = 0.006).

CONCLUSIONS

In the FIA study, among the affected patients' FDRs who are > 30 years of age, those who are women or who have a history of smoking or hypertension are at increased risk of suffering an IA and should be strongly considered for screening.

Genome screen to detect linkage to intracranial aneurysm susceptibility genes: the Familial Intracranial Aneurysm (FIA) study

BACKGROUND AND PURPOSE

Evidence supports a substantial genetic contribution to the risk of intracranial aneurysm (IA). The purpose of this study was to identify chromosomal regions likely to harbor genes that contribute to the risk of IA.

METHODS

Multiplex families having at least 2 individuals with "definite" or "probable" IA were ascertained through an international consortium. First-degree relatives of individuals with IA who were at increased risk of an IA because of a history of hypertension or present smoking were offered cerebral magnetic resonance angiography. A genome screen was completed using the Illumina 6K SNP system, and the resulting data from 192 families, containing 1155 genotyped individuals, were analyzed. Narrow and broad disease definitions were used when testing for linkage using multipoint model-independent methods. Ordered subset analysis was performed to test for a gene x smoking (pack-years) interaction.

RESULTS

The greatest evidence of linkage was found on chromosomes 4 (LOD=2.5; 156 cM), 7 (LOD=1.7; 183 cM), 8 (LOD=1.9; 70 cM), and 12 (LOD=1.6; 102 cM) using the broad disease definition. Using the average pack-years for the affected individuals in each family, the genes on chromosomes 4 (LOD=3.5; P=0.03), 7 (LOD=4.1; P=0.01) and 12 (LOD=3.6; P=0.02) all appear to be modulated by the degree of smoking in the affected members of the family. On chromosome 8, inclusion of smoking as a covariate did not significantly strengthen the linkage evidence, suggesting no interaction between the loci in this region and smoking.

CONCLUSIONS

We have detected possible evidence of linkage to 4 chromosomal regions. There is potential evidence for a gene x smoking interaction with 3 of the loci.

Awareness of stroke risk factors, symptoms, and treatment is poor in people at highest risk

We designed this study to determine factors associated with community stroke knowledge that could be used to improve education strategies. A survey was mailed to random adult residents of Olmsted County, Minnesota. The questions assessed knowledge of stroke (definition, treatment, symptoms, and risk factors) and access to and attitudes toward health care. Background information was obtained from medical records for responders and non-responders. Chi square and multivariate logistic regression analyses were used to identify predictors of stroke. Three hundred and sixty four (36%) of 1086 written surveys were returned. The mean age of respondents was 51.6 years. "Stroke" was incorrectly defined by 40% of respondents. Only 67% of respondents correctly identified stroke risk factors. Paralysis was commonly recognized as a symptom of stroke; only 42% of persons, however, would first call 911 if having a stroke. The thrombolytic treatment window was not known by 32%. Participants concerned about health care cost and access were less likely to correctly answer questions about symptoms or treatment. People with stroke risk factors or a personal or family history of stroke or transient ischemic attack were no more knowledgeable about stroke than those without. We concluded that knowledge of stroke is poor, even among persons with a previous stroke or risk factors for stroke. There is a lack of awareness that acute ischemic stroke therapy exists and that it must be used in an urgent fashion. Structured education programs for stroke awareness must be multi-faceted, targeting those persons at high risk while at the same time accounting for health care cost concerns, confidence in the medical community, and the needs of the elderly.

Reprint of: SYMPOSIUM ON CEREBROVASCULAR DISEASES. Pathogenesis, Natural History, and Treatment of Unruptured Intracranial Aneurysms

Unruptured intracranial aneurysms (UIAs) are a major public health issue. These lesions have become increasingly recognized in recent years with the advent of advanced cerebral imaging techniques. Epidemiological evidence from multiple sources suggests that most intracranial aneurysms do not rupture. Therefore, it is desirable to identify which UIAs are at greatest risk of rupture when considering which to repair. It is important to compare size-, site-, and group-specific natural history rates with size-, site-, and age-specific morbidity and mortality associated with UIA repair because increased natural history risk often is associated with increased risk of aneurysm repair. Patient age is crucial in decision making because of its major effect on operative morbidity and mortality; however, it does not substantially affect natural history. The effect of age is most notable in patients about 50 years of age and older for open surgery and about 70 years of age and older for endovascular procedures. In general, rupture risk is lowest for patients in asymptomatic group 1 (no history of subarachnoid hemorrhage) with UIAs less than 7 mm in diameter in the anterior circulation. Surgical morbidity and mortality are most favorable for asymptomatic patients younger than 50 years who have UIAs less than 24 mm in diameter in the anterior circulation and no history of ischemic cerebrovascular disease. Endovascular morbidity and mortality may be less age dependent, and this could favor endovascular procedures, particularly in patients aged 50 to 70 years. An important issue is determining immediate vs long-term risk regarding treatment effectiveness and durability. This issue emphasizes the importance of long-term follow-up in patients after surgical and endovascular procedures.

Clinical, laboratory, and transesophageal echocardiographic correlates of interatrial septal thickness: a population-based transesophageal echocardiographic study

BACKGROUND

The determinants of interatrial septal (IAS) thickening ("lipomatous hypertrophy"), a common echocardiographic finding in the elderly, are poorly defined. The objective of this study was to determine the clinical, laboratory, and transesophageal echocardiographic correlates of IAS thickening in the general population.

METHODS

The thickness of the IAS was measured by transesophageal echocardiography in 384 patients (median age: 66 years; range: 51-101 years; 53% men) participating in a population-based study (Stroke Prevention: Assessment of Risk in a Community). The associations between atherosclerosis risk factors, clinical cardiovascular disease, aortic atherosclerotic plaques, and IAS thickness were examined.

RESULTS

Age and body surface area (BSA) were significantly associated with IAS thickness (median: 6 mm; range: 2-17 mm). IAS thickness increased by 12.6% per 10 years of age (95% confidence interval: 9.0-16.4%) adjusting for sex and BSA, and increased by 7.0% per 0.1 m 2 BSA (confidence interval: 5.0-9.2%) adjusting for age and sex. Overall, age, sex, and BSA accounted for 22.5% of the variability in IAS thickness. Current smoking (20.4% increase in IAS thickness in current smokers) and hypertension treatment (8.5% increase in treated patients) were associated with increased IAS thickness, adjusting for age, sex, and BSA ( P < .05), but these two risk factor variables jointly explained only an additional 2.3% of the variability in IAS thickness beyond the variability explained by age, sex, and BSA. Clinical coronary artery and cerebrovascular disease, atrial arrhythmias, and aortic atherosclerotic plaques were not associated with IAS thickness, adjusting for age, sex, and BSA ( P > .3).

CONCLUSIONS

IAS thickening is an age-associated process. Atherosclerosis risk factors are weakly associated with IAS thickening, whereas atherosclerotic vascular disease is not.

Update on evidence for a genetic predisposition to cerebral vasospasm

✓ Considerable evidence links cerebral vasospasm to the decreased bioavailability of endothelial nitric oxide synthase (eNOS) after aneurysmal subarachnoid hemorrhage (SAH). In recent studies from the cardiology literature, researchers have suggested that a genetic predisposition to coronary vasospasm might develop as the result of a T-786C single nucleotide polymorphism (SNP) in the eNOS gene. The authors of this study attempted to determine if there may be a similar genetic predisposition toward cerebral vasospasm.

The authors prospectively identified 28 patients with Fisher Grade 3 SAH from a group of 51 consecutive patients with ruptured intracranial saccular aneurysms. Genomic DNA was isolated from a peripheral blood sample obtained with permission from each patient. Gene microarray technology was used to assay the samples for the presence and distribution of certain key eNOS gene polymorphisms. Clinical, radiological, and genomic data were analyzed. The finding of eNOS T-786C SNP could be used to significantly differentiate between the presence and severity of cerebral vasospasm (p = 0.04).

The findings from this preliminary study support similar findings in the coronary vasospasm literature as well as the hypothesis that a predisposition toward cerebral vasospasm may be related partially to genetic factors, which needs to be confirmed in a larger study. Such gene-based information may be important in rapidly identifying patients at increased risk of vasospasm after SAH, independent of their Fisher grade. In this article, the authors review key studies in this area.

Population-based study of the relationship between atherosclerotic aortic debris and cerebrovascular ischemic events

OBJECTIVE

To assess the validity of the suggestion that protruding atheromatous material in the thoracic aorta is an important cause of cerebrovascular ischemic events (CIEs) (ie, transient ischemic attack or ischemic stroke).

METHODS

This case-control study of Olmsted County, Minnesota, residents who underwent transesophageal echocardiography (TEE) from 1993 to 1997 included controls without CIE randomly selected from the population, controls without CIE referred for TEE because of cardiac disease, cases with incident CIE of obvious cause (noncryptogenic), and cases with incident CIE of uncertain cause (cryptogenic).

RESULTS

Of the 1135 subjects, 520 were randomly selected controls without CIE, 329 were controls without CIE referred for TEE, 159 were noncryptogenic CIE cases, and 127 were cryptogenic CIE cases. Complex atherosclerotic aortic debris in ascending and transverse segments of the arch was detected in 8 randomly selected controls (1.5%), 13 referred controls (4.0%), and 15 noncryptogenic (9.4%) and 4 cryptogenic (3.1%) CIE cases. After adjusting for age, sex, hypertension, smoking, atrial fibrillation, valvular heart disease, congestive heart failure, and atherosclerosis other than in the thoracic aorta, complex atherosclerotic aortic debris was not significantly associated with group status. With randomly selected controls as the referent group, odds ratios (95% confidence intervals) were 1.72 (0.61-4.87) for referred controls, 3.16 (1.18-8.51) for noncryptogenic CIE cases, and 1.39 (0.39-4.88) for cryptogenic CIE cases.

CONCLUSIONS

Complex atherosclerotic aortic debris is not a risk factor for cryptogenic ischemic stroke or transient ischemic attack but is a marker for generalized atherosclerosis and well-established atherosclerotic and cardioembolic mechanisms of cerebral ischemia. Embolization from the aorta is not a common mechanism of ischemic stroke or transient ischemic attack.

Population-based study of the relationship between patent foramen ovale and cerebrovascular ischemic events

OBJECTIVE

To determine whether patent foramen ovale (PFO) is a risk factor for a cryptogenic cerebrovascular ischemic event (CIE).

METHODS

This case-control study of 1072 residents of Olmsted County, Minnesota, who underwent contrast transesophageal echocardiography between 1993 and 1997 included 519 controls without CIE randomly selected from the population, 262 controls without CIE referred for transesophageal echocardiography because of cardiac disease, 158 cases with incident CIE of obvious cause (noncryptogenic), and 133 cases with incident CIE of uncertain cause (cryptogenic).

RESULTS

Large PFOs were detected in 108 randomly selected controls (20.8%), 22 referred controls (8.4%), 17 noncryptogenic CIE cases (10.8%), and 22 cryptogenic CIE cases (16.5%). After adjustment for age, sex, hypertension, smoking, atrial fibrillation, ischemic heart disease, and number of contrast injections, the presence of a large PFO was not significantly associated with group status (P=.07). Using the odds of the presence of large PFO in the randomly selected controls as the reference, the odds ratio (95% confidence interval) of the presence of large PFO was 0.47 (0.26-0.87) for referred controls, 0.69 (0.37-1.29) for noncryptogenic CIE cases, and 1.10 (0.63-1.90) for cryptogenic CIE cases.

CONCLUSIONS

Patent foramen ovale is not a risk factor for cryptogenic ischemic stroke or transient ischemic attack in the general population. The PFO's importance in the genesis of cryptogenic CIE may have been overestimated in previous studies because of selective referral of cases and underascertainment of PFO among comparison groups of patients referred for echocardiography for clinical indications other than cryptogenic CIE.

Patent foramen ovale: innocent or guilty? Evidence from a prospective population-based study

OBJECTIVES

We sought to determine the association between patent foramen ovale (PFO), atrial septal aneurysm (ASA), and stroke prospectively in a unselected population sample.

BACKGROUND

The disputed relationship between PFO and stroke reflects methodologic weaknesses in studies using invalid controls, unblinded transesophageal echocardiography examinations, and data that are unadjusted for age or comorbidity.

METHODS

The use of transesophageal echocardiography to identify PFO was performed by a single echocardiographer using standardized definitions in 585 randomly sampled, Olmsted County (Minnesota) subjects age 45 years or older participating in the Stroke Prevention: Assessment of Risk in a Community (SPARC) study.

RESULTS

A PFO was identified in 140 (24.3%) subjects and ASA in 11 (1.9%) subjects. Of the 140 subjects with PFO, 6 (4.3%) had an ASA; of the 437 subjects without PFO, 5 had an ASA (1.1%, two-sided Fisher exact test, p = 0.028). During a median follow-up of 5.1 years, cerebrovascular events (cerebrovascular disease-related death, ischemic stroke, transient ischemic attack) occurred in 41 subjects. After adjustment for age and comorbidity, PFO was not a significant independent predictor of stroke (hazard ratio 1.46, 95% confidence interval 0.74 to 2.88, p = 0.28). The risk of a cerebrovascular event among subjects with ASA was nearly four times higher than that in those without ASA (hazard ratio 3.72, 95% confidence interval 0.88 to 15.71, p = 0.074).

CONCLUSIONS

These prospective population-based data suggest that, after correction for age and comorbidity, PFO is not an independent risk factor for future cerebrovascular events in the general population. A larger study is required to test the putative stroke risk associated with ASA.

The management of patients with patent foramen ovale and stroke

The management of patients with patent foramen ovale (PFO) and stroke remains uncertain. What is known is that PFO is a very common finding in the general population. The risk of initial and recurrent stroke in individuals with PFO is relatively low. With the advent of transesophageal echocardiography, PFO is more commonly being diagnosed. There are insufficient data to support a benefit of warfarin over aspirin in preventing recurrent stroke in most patients with PFO. In those with PFO and a history of a procoagulant state or deep venous thrombosis, anticoagulation may be indicated after weighing the risks of anticoagulation against potential benefits in preventing recurrent stroke. PFO closure does not guarantee the prevention of future stroke and should be addressed case by case, with consideration of patients for entry into ongoing clinical trials of safety, efficacy, and durability.

The Familial Intracranial Aneurysm (FIA) study protocol

Background

Subarachnoid hemorrhage (SAH) due to ruptured intracranial aneurysms (IAs) occurs in about 20,000 people per year in the U.S. annually and nearly half of the affected persons are dead within the first 30 days. Survivors of ruptured IAs are often left with substantial disability. Thus, primary prevention of aneurysm formation and rupture is of paramount importance. Prior studies indicate that genetic factors are important in the formation and rupture of IAs. The long-term goal of the Familial Intracranial Aneurysm (FIA) Study is to identify genes that underlie the development and rupture of intracranial aneurysms (IA).

Methods/Design

The FIA Study includes 26 clinical centers which have extensive experience in the clinical management and imaging of intracerebral aneurysms. 475 families with affected sib pairs or with multiple affected relatives will be enrolled through retrospective and prospective screening of potential subjects with an IA. After giving informed consent, the proband or their spokesperson invites other family members to participate. Each participant is interviewed using a standardized questionnaire which covers medical history, social history and demographic information. In addition blood is drawn from each participant for DNA isolation and immortalization of lymphocytes. High- risk family members without a previously diagnosed IA undergo magnetic resonance angiography (MRA) to identify asymptomatic unruptured aneurysms. A 10 cM genome screen will be performed to identify FIA susceptibility loci. Due to the significant mortality of affected individuals, novel approaches are employed to reconstruct the genotype of critical deceased individuals. These include the intensive recruitment of the spouse and children of deceased, affected individuals.

Discussion

A successful, adequately-powered genetic linkage study of IA is challenging given the very high, early mortality of ruptured IA. Design features in the FIA Study that address this challenge include recruitment at a large number of highly active clinical centers, comprehensive screening and recruitment techniques, non-invasive vascular imaging of high-risk subjects, genome reconstruction of dead affected individuals using marker data from closely related family members, and inclusion of environmental covariates in the statistical analysis.

The presence of tandem endothelial nitric oxide synthase gene polymorphisms identifying brain aneurysms more prone to rupture

Object. It is becoming apparent that the presence of certain genetic variations (polymorphisms) may increase the individual's susceptibility to cardiovascular diseases, even in the absence of a family history. We hypothesized that brain aneurysms more prone to rupture may be identified on the basis of an individual's genotype for endothelial nitric oxide synthase (eNOS), a critical vasomodulatory protein found to be increasingly relevant to the pathobiology of aneurysms.

Methods. Patients' clinical data were recorded prospectively. Genomic DNA was isolated from blood samples obtained from individuals presenting consecutively to the Mayo Clinic with ruptured (58 patients) or unruptured (49 patients) intracranial saccular aneurysms. Using polymerase chain reaction and gene microarray technology, the following eNOS genetic polymorphisms were studied: intron-4 27—base pair variable number of tandem repeats (27 VNTR); promoter single nucleotide polymorphism (T-786C SNP); and exon-7 SNP (G894T SNP).

Both groups of patients had similar demographic and clinical characteristics. For all three polymorphisms, variant alleles (p ≤ 0.003) and their corresponding genotypes (p ≤ 0.006) were found two to four times more frequently in patients with ruptured aneurysms than in patients with unruptured aneurysms. Strikingly, the odds ratio for presenting with a ruptured brain aneurysm among individuals demonstrating the copresence of all three variant alleles was 11.4 (95% confidence interval 1.7–75.9, p = 0.004).

Conclusions. The authors have uniquely identified a set of tandem eNOS gene variations whose presence can be used to identify patients with aneurysms likely to rupture. We believe that if this finding is reproducible in a large multicenter study, in addition to known anatomical factors a rapid and cost-effective screening tool will become available to clinicians as a genetic aid to predict the risks of rupture in patients presenting with unruptured intracranial aneurysms.

Pathogenesis, natural history, and treatment of unruptured intracranial aneurysms

Unruptured intracranial aneurysms (UIAs) are a major public health issue. These lesions have become increasingly recognized in recent years with the advent of advanced cerebral imaging techniques. Epidemiological evidence from multiple sources suggests that most intracranial aneurysms do not rupture. Therefore, it is desirable to identify which UIAs are at greatest risk of rupture when considering which to repair. It is important to compare size-, site-, and group-specific natural history rates with size-, site-, and age-specific morbidity and mortality associated with UIA repair because increased natural history risk often is associated with increased risk of aneurysm repair. Patient age is crucial in decision making because of its major effect on operative morbidity and mortality; however, it does not substantially affect natural history. The effect of age is most notable in patients about 50 years of age and older for open surgery and about 70 years of age and older for endovascular procedures. In general, rupture risk is lowest for patients in asymptomatic group 1 (no history of subarachnoid hemorrhage) with UIAs less than 7 mm in diameter in the anterior circulation. Surgical morbidity and mortality are most favorable for asymptomatic patients younger than 50 years who have UIAs less than 24 mm in diameter in the anterior circulation and no history of ischemic cerebrovascular disease. Endovascular morbidity and mortality may be less age dependent, and this could favor endovascular procedures, particularly in patients aged 50 to 70 years. An important issue is determining immediate vs long-term risk regarding treatment effectiveness and durability. This issue emphasizes the importance of long-term follow-up in patients after surgical and endovascular procedures.

Update on genetic evidence for rupture-prone compared with rupture-resistant intracranial saccular aneurysms

Object

Anecdotal evidence exists for at least two subpopulations of intracranial saccular aneurysms; those that form rapidly and rupture when small and those that enlarge slowly and are particularly prone to rupture when they are 10 mm or more in diameter. The goal in this study was to determine if there was genetic evidence to support the classification of intracranial saccular aneurysms as “rupture-prone” or “rupture-resistant” lesions.

Methods

The authors prospectively obtained and analyzed clinical and genetic data in a cohort of 197 individuals composed of 58 patients with ruptured intracranial saccular aneurysms, 49 with unruptured aneurysms, and 90 healthy community volunteers. Based on recent studies supporting an increasingly relevant role for the critical vasomodulatory protein endothelial nitric oxide synthase (eNOS) in aneurysm pathobiology, the authors assayed blood from all 197 participants to determine and compare their eNOS genotypes.

TheeNOSgene intron 4 27–base pair variable-number tandem-repeat polymorphism was significantly overrepre-sented in persons with ruptured intracranial saccular aneurysms compared with community volunteers (p <0.002). When comparing eNOS genotypes among patients with ruptured or unruptured aneurysms, an approximately 10-fold increase in the odds of presenting with brain aneurysm rupture was found among individuals with multiple variant eNOS alleles (p = 0.004).

Conclusions

Uniquely, the authors have identified a set ofeNOSgene variations whose presence indicates patients with intracranial saccular aneurysms that are more prone to rupture. The authors conclude that if these findings are reproducible in the setting of a large multicenter study, then in addition to known anatomical factors, a rapid and cost-effective genetic screening tool will become available to clinicians as an aid to predicting rupture risks in patients presenting with unruptured intracranial aneurysms.

C-Reactive Protein and Atherosclerosis of the Thoracic Aorta

BACKGROUND

An association between systemic inflammatory markers and the presence and severity of atherosclerotic plaques has not been demonstrated in a nonselected population. The purpose of this study was to examine the association of inflammatory markers with aortic atherosclerotic plaques in a sample of the general population and in a subgroup free of clinical vascular disease.

METHODS

Transesophageal echocardiography was performed in 386 subjects (median age, 66 years; 53% men). We examined the association between systemic inflammatory markers and aortic atherosclerotic plaques.

RESULTS

Aortic plaques were present in 267 subjects (69%). Plaques at least 4 and 6 mm thick and mobile debris were present in 114, 41, and 20 subjects, respectively. High-sensitivity C-reactive protein (hs-CRP) level was associated with the presence of aortic plaques, adjusting for age, sex, smoking status, and additional atherosclerosis risk factors. Among subjects with plaques, hs-CRP level was independently associated with plaques at least 6 mm thick; similar trends were observed for the associations of hs-CRP level with plaques at least 4 mm thick and mobile debris. In subjects with aortic plaques who were free of clinically apparent coronary artery or cerebrovascular disease, hs-CRP level was independently associated with plaques at least 6 mm thick.

CONCLUSIONS

Level of hs-CRP is independently associated with the presence and severity of aortic atherosclerotic plaques. These observations establish the association of systemic inflammation with anatomically defined atherosclerosis in the general population.

Atherosclerosis of the aorta: Risk factor, risk marker, or innocent bystander?

OBJECTIVES

The goal of this study was to investigate whether complex aortic atherosclerosis is associated with increased risk of vascular events in a non-selected population.

BACKGROUND

In selected high-risk patients, aortic atherosclerosis is associated with increased risk of vascular events.

METHODS

We describe the relationship between simple versus complex (>4-mm thick or mobile debris) aortic atherosclerotic plaques and vascular events during follow-up in a random sample of 585 persons (age > or =45 years) using 1993 to 2000 data from the Stroke Prevention: Assessment of Risk in a Community (SPARC), a prospective population-based longitudinal study.

RESULTS

At five-year median follow-up (range, 0.5 to 6.5 years), cardiac events (death, non-fatal myocardial infarction, coronary revascularization, heart failure associated with coronary artery disease) and cerebrovascular events (ischemic fatal and non-fatal strokes, transient ischemic attacks) had occurred in 95 subjects and 41 subjects, respectively. Age, male gender, prior coronary artery disease, higher pulse pressure, and diabetes were significant cardiovascular predictors. Age, prior myocardial infarction, and a history of atrial fibrillation were significant cerebrovascular predictors. Simple aortic plaques (253 persons) were not independently associated with either cardiac or cerebrovascular events. Complex plaques (44 persons) were marginally associated with cardiac events, adjusting for age and gender (hazard ratio [HR], 2.28; 95% confidence interval [CI], 1.11 to 4.68; p = 0.053 for two degrees of freedom [complex and simple plaques vs. no plaques]) but not after adjusting for additional clinical risk factors (HR, 1.22; 95% CI, 0.57 to 2.62; p = 0.64). Complex plaques were associated with cerebrovascular events only univariately.

CONCLUSIONS

Aortic atherosclerotic plaques are not associated with future cardiac or cerebrovascular events. Aortic atherosclerosis may not be an independent risk factor for vascular events in the general population.