Anthony Wan, Blessing N. R. Jaja, Tom A. Schweizer and R. Loch Macdonald
Intracerebral hematoma (ICH) with subarachnoid hemorrhage (SAH) indicates a unique feature of intracranial aneurysm rupture since the aneurysm is in the subarachnoid space and separated from the brain by pia mater. Broad consensus is lacking regarding the concept that ultra-early treatment improves outcome. The aim of this study is to determine the associative factors for ICH, ascertain the prognostic value of ICH, and investigate how the timing of treatment relates to the outcome of SAH with concurrent ICH.
The study data were pooled from the SAH International Trialists repository. Logistic regression was applied to study the associations of clinical and aneurysm characteristics with ICH. Proportional odds models and dominance analysis were applied to study the effect of ICH on 3-month outcome (Glasgow Outcome Scale) and investigate the effect of time from ictus to treatment on outcome.
Of the 5362 SAH patients analyzed, 1120 (21%) had concurrent ICH. In order of importance, neurological status, aneurysm location, aneurysm size, and patient ethnicity were significantly associated with ICH. Patients with ICH experienced poorer outcome than those without ICH (OR 1.58; 95% CI 1.37–1.82). Treatment within 6 hours of SAH was associated with poorer outcome than treatment thereafter (adjusted OR 1.67; 95% CI 1.04–2.69). Subgroup analysis with adjustment for ICH volume, location, and midline shift resulted in no association between time from ictus to treatment and outcome (OR 0.99; 95% CI 0.94–1.07).
The most important associative factor for ICH is neurological status on admission. The finding regarding the value of ultra-early treatment suggests the need to more robustly reevaluate the concept that hematoma evacuation of an ICH and repair of a ruptured aneurysm within 6 hours of ictus is the most optimal treatment path.
Menno R. Germans, Blessing N. R. Jaja, Airton Leonardo de Oliviera Manoel, Ashley H. Cohen and R. Loch Macdonald
In this study the authors sought to investigate the sex differences in the risk of delayed cerebral ischemia (DCI), delayed cerebral infarction, and the role of hormonal status.
Ten studies included in the SAHIT (SAH International Trialists) repository were analyzed using a fitting logistic regression model. Heterogeneity between the studies was tested using I2 statistics, and the results were pooled using a random-effects model. Multivariable analysis was adjusted for the effects of neurological status and fixed effect of study. An additional model was examined in which women and men were split into groups according to an age cut point of 55 years, as a surrogate to define hormonal status.
A pooled cohort of 6713 patients was analyzed. The risk of DCI was statistically significantly higher in women than in men (OR 1.29, 95% CI 1.12–1.48); no difference was found with respect to cerebral infarction (OR 1.17, 95% CI 0.98–1.40). No difference was found in the risk of DCI when comparing women ≤ 55 and > 55 years (OR 0.87, 95% CI 0.74–1.02; p = 0.08) or when comparing men ≤ 55 and > 55 years (p = 0.38). Independent predictors of DCI were World Federation of Neurosurgical Societies (WFNS) grade, Fisher grade, age, and sex. Independent predictors of infarction included WFNS grade, Fisher grade, and aneurysm size.
Female sex is associated with a higher risk of DCI. Sex differences may play a role in the pathogenesis of DCI but are not associated with menopausal status. The predictors of DCI and cerebral infarction were identified in a very large cohort and reflect experience from multiple institutions.
Blessing N. R. Jaja, Hester Lingsma, Ewout W. Steyerberg, Tom A. Schweizer, Kevin E. Thorpe and R. Loch Macdonald
Neuroimaging characteristics of ruptured aneurysms are important to guide treatment selection, and they have been studied for their value as outcome predictors following aneurysmal subarachnoid hemorrhage (SAH). Despite multiple studies, the prognostic value of aneurysm diameter, location, and extravasated SAH clot on computed tomography scan remains debatable. The authors aimed to more precisely ascertain the relation of these factors to outcome.
The data sets of studies included in the Subarachnoid Hemorrhage International Trialists (SAHIT) repository were analyzed including data on ruptured aneurysm location and diameter (7 studies, n = 9125) and on subarachnoid clot graded on the Fisher scale (8 studies; n = 9452) for the relation to outcome on the Glasgow Outcome Scale (GOS) at 3 months. Prognostic strength was quantified by fitting proportional odds logistic regression models. Univariable odds ratios (ORs) were pooled across studies using random effects models. Multivariable analyses were adjusted for fixed effect of study, age, neurological status on admission, other neuroimaging factors, and treatment modality. The neuroimaging predictors were assessed for their added incremental predictive value measured as partial R2.
Spline plots indicated outcomes were worse at extremes of aneurysm size, i.e., less than 4 or greater than 9 mm. In between, aneurysm size had no effect on outcome (OR 1.03, 95% CI 0.98–1.09 for 9 mm vs 4 mm, i.e., 75th vs 25th percentile), except in those who were treated conservatively (OR 1.17, 95% CI 1.02–1.35). Compared with anterior cerebral artery aneurysms, posterior circulation aneurysms tended to result in slightly poorer outcome in patients who underwent endovascular coil embolization (OR 1.13, 95% CI 0.82–1.57) or surgical clipping (OR 1.32, 95% CI 1.10–1.57); the relation was statistically significant only in the latter. Fisher CT subarachnoid clot burden was related to outcome in a gradient manner. Each of the studied predictors accounted for less than 1% of the explained variance in outcome.
This study, which is based on the largest cohort of patients so far analyzed, has more precisely determined the prognostic value of the studied neuroimaging factors. Treatment choice has strong influence on the prognostic effect of aneurysm size and location. These findings should guide the development of reliable prognostic models and inform the design and analysis of future prospective studies, including clinical trials.
Blessing N. R. Jaja, Hester Lingsma, Tom A. Schweizer, Kevin E. Thorpe, Ewout W. Steyerberg and R. Loch Macdonald
The literature has conflicting reports about the prognostic value of premorbid hypertension and neurological status in aneurysmal subarachnoid hemorrhage (SAH). The aim of this study was to investigate the prognostic value of premorbid hypertension and neurological status in the SAH International Trialists repository.
Patient-level meta-analyses were conducted to investigate univariate associations between premorbid hypertension (6 studies; n = 7249), admission neurological status measured on the World Federation of Neurosurgical Societies (WFNS) scale (10 studies; n = 10,869), and 3-month Glasgow Outcome Scale (GOS) score. Multivariable analyses were performed to sequentially adjust for the effects of age, CT clot burden, aneurysm location, aneurysm size, and modality of aneurysm repair. Prognostic associations were estimated across the ordered categories of the GOS using proportional odds models. Nagelkerke's R2 statistic was used to quantify the added prognostic value of hypertension and neurological status beyond those of the adjustment factors.
Premorbid hypertension was independently associated with poor outcome, with an unadjusted pooled odds ratio (OR) of 1.73 (95% confidence interval [CI] 1.50–2.00) and an adjusted OR of 1.38 (95% CI 1.25–1.53). Patients with a premorbid history of hypertension had higher rates of cardiovascular and renal comorbidities, poorer neurological status (p ≤ 0.001), and higher odds of neurological complications including cerebral infarctions, hydrocephalus, rebleeding, and delayed ischemic neurological deficits. Worsening neurological status was strongly independently associated with poor outcome, including WFNS Grades II (OR 1.85, 95% CI 1.68–2.03), III (OR 3.85, 95% CI 3.32–4.47), IV (OR 5.58, 95% CI 4.91–6.35), and V (OR 14.18, 95% CI 12.20–16.49). Neurological status had substantial added predictive value greater than the combined value of other prognostic factors (R2 increase > 10%), while the added predictive value of hypertension was marginal (R2 increase < 0.5%).
This study confirmed the strong prognostic effect of neurological status as measured on the WFNS scale and the independent but weak prognostic effect of premorbid hypertension. The effect of premorbid hypertension could involve multifactorial mechanisms, including an increase in the severity of initial bleeding, the rate of comorbid events, and neurological complications.
Blessing N. R. Jaja, Gustavo Saposnik, Rosane Nisenbaum, Benjamin W. Y. Lo, Tom A. Schweizer, Kevin E. Thorpe and R. Loch Macdonald
The goal of this study was to determine racial/ethnic differences in inpatient mortality rates and the use of institutional postacute care following subarachnoid hemorrhage (SAH) in the US.
A cross-sectional study of hospital discharges for SAH was conducted using the Nationwide Inpatient Sample for the years 2005–2010. Discharges with a principal diagnosis of SAH were identified and abstracted using the appropriate ICD-9-CM diagnostic code. Racial/ethnic groups were defined as white, black, Hispanic, Asian/Pacific Islander (API), and American Indian. Multinomial logistic regression analyses were performed comparing racial/ethnic groups with respect to the primary outcome of risk of in-hospital mortality and the secondary outcome of likelihood of discharge to institutional care.
During the study period, 31,631 discharges were related to SAH. Race/ethnicity was a significant predictor of death (p = 0.003) and discharge to institutional care (p ≤ 0.001). In the adjusted analysis, compared with white patients, API patients were at higher risk of death (OR 1.34, 95% CI 1.13–1.59) and Hispanic patients were at lower risk of death (OR 0.84, 95% CI 0.72–0.97). The likelihood of discharge to institutional care was statistically similar between white, Hispanic, API, and Native American patients. Black patients were more likely to be discharged to institutional care compared with white patients (OR 1.27, 95% CI 1.14–1.40), but were similar to white patients in the risk of death.
Significant racial/ethnic differences are present in the risk of inpatient mortality and discharge to institutional care among patients with SAH in the US. Outcome is likely to be poor among API patients and best among Hispanic patients compared with other groups.
Naif M. Alotaibi, Ghassan Awad Elkarim, Nardin Samuel, Oliver G. S. Ayling, Daipayan Guha, Aria Fallah, Abdulrahman Aldakkan, Blessing N. R. Jaja, Airton Leonardo de Oliveira Manoel, George M. Ibrahim and R. Loch Macdonald
Patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH) (World Federation of Neurosurgical Societies Grade IV or V) are often considered for decompressive craniectomy (DC) as a rescue therapy for refractory intracranial hypertension. The authors performed a systematic review and meta-analysis to assess the impact of DC on functional outcome and death in patients after poor-grade aSAH.
A systematic review and meta-analysis were performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Articles were identified through the Ovid Medline, Embase, Web of Science, and Cochrane Library databases from inception to October 2015. Only studies dedicated to patients with poor-grade aSAH were included. Primary outcomes were death and functional outcome assessed at any time period. Patients were grouped as having a favorable outcome (modified Rankin Scale [mRS] Scores 1–3, Glasgow Outcome Scale [GOS] Scores 4 and 5, extended Glasgow Outcome Scale [GOSE] Scores 5–8) or unfavorable outcome (mRS Scores 4–6, GOS Scores 1–3, GOSE Scores 1–4). Pooled estimates of event rates and odds ratios with 95% confidence intervals were calculated using the random-effects model.
Fifteen studies encompassing 407 patients were included in the meta-analysis (all observational cohorts). The pooled event rate for poor outcome across all studies was 61.2% (95% CI 52%–69%) and for death was 27.8% (95% CI 21%–35%) at a median of 12 months after aSAH. Primary (or early) DC resulted in a lower overall event rate for unfavorable outcome than secondary (or delayed) DC (47.5% [95% CI 31%–64%] vs 74.4% [95% CI 43%–91%], respectively). Among studies with comparison groups, there was a trend toward a reduced mortality rate 1–3 months after discharge among patients who did not undergo DC (OR 0.58 [95% CI 0.27–1.25]; p = 0.168). However, this trend was not sustained at the 1-year follow-up (OR 1.09 [95% CI 0.55–2.13]; p = 0.79).
Results of this study summarize the best evidence available in the literature for DC in patients with poor-grade aSAH. DC is associated with high rates of unfavorable outcome and death. Because of the lack of robust control groups in a majority of the studies, the effect of DC on functional outcomes versus that of other interventions for refractory intracranial hypertension is still unknown. A randomized trial is needed.
Simone A. Dijkland, Blessing N. R. Jaja, Mathieu van der Jagt, Bob Roozenbeek, Mervyn D. I. Vergouwen, Jose I. Suarez, James C. Torner, Michael M. Todd, Walter M. van den Bergh, Gustavo Saposnik, Daniel W. Zumofen, Michael D. Cusimano, Stephan A. Mayer, Benjamin W. Y. Lo, Ewout W. Steyerberg, Diederik W. J. Dippel, Tom A. Schweizer, R. Loch Macdonald and Hester F. Lingsma
Differences in clinical outcomes between centers and countries may reflect variation in patient characteristics, diagnostic and therapeutic policies, or quality of care. The purpose of this study was to investigate the presence and magnitude of between-center and between-country differences in outcome after aneurysmal subarachnoid hemorrhage (aSAH).
The authors analyzed data from 5972 aSAH patients enrolled in randomized clinical trials of 3 different treatments from the Subarachnoid Hemorrhage International Trialists (SAHIT) repository, including data from 179 centers and 20 countries. They used random effects logistic regression adjusted for patient characteristics and timing of aneurysm treatment to estimate between-center and between-country differences in unfavorable outcome, defined as a Glasgow Outcome Scale score of 1–3 (severe disability, vegetative state, or death) or modified Rankin Scale score of 4–6 (moderately severe disability, severe disability, or death) at 3 months. Between-center and between-country differences were quantified with the median odds ratio (MOR), which can be interpreted as the ratio of odds of unfavorable outcome between a typical high-risk and a typical low-risk center or country.
The proportion of patients with unfavorable outcome was 27% (n = 1599). The authors found substantial between-center differences (MOR 1.26, 95% CI 1.16–1.52), which could not be explained by patient characteristics and timing of aneurysm treatment (adjusted MOR 1.21, 95% CI 1.11–1.44). They observed no between-country differences (adjusted MOR 1.13, 95% CI 1.00–1.40).
Clinical outcomes after aSAH differ between centers. These differences could not be explained by patient characteristics or timing of aneurysm treatment. Further research is needed to confirm the presence of differences in outcome after aSAH between hospitals in more recent data and to investigate potential causes.