Development and validation of outcome prediction models for aneurysmal subarachnoid haemorrhage: the SAHIT multinational cohort study

Abstract

Objective -To develop and validate a set of practical prediction tools that reliably estimate the outcome of subarachnoid haemorrhage from ruptured intracranial aneurysms (SAH).Design -Cohort study with logistic regression analysis to combine predictors and treatment modality.Setting -Subarachnoid Haemorrhage International Trialists' (SAHIT) data repository, including randomised clinical trials, prospective observational studies, and hospital registries.Participants -Researchers collaborated to pool datasets of prospective observational studies, hospital registries, and randomised clinical trials of SAH from multiple geographical regions to develop and validate clinical prediction models.Main outcome measure -Predicted risk of mortality or functional outcome at three months according to score on the Glasgow outcome scale.Results -Clinical prediction models were developed with individual patient data from 10 936 patients and validated with data from 3355 patients after development of the model. In the validation cohort, a core model including patient age, premorbid hypertension, and neurological grade on admission to predict risk of functional outcome had good discrimination, with an area under the receiver operator characteristics curve (AUC) of 0.80 (95% confidence interval 0.78 to 0.82). When the core model was extended to a "neuroimaging model," with inclusion of clot volume, aneurysm size, and location, the AUC improved to 0.81 (0.79 to 0.84). A full model that extended the neuroimaging model by including treatment modality had AUC of 0.81 (0.79 to 0.83). Discrimination was lower for a similar set of models to predict risk of mortality (AUC for full model 0.76, 0.69 to 0.82). All models showed satisfactory calibration in the validation cohort. Conclusion -The prediction models reliably estimate the outcome of patients who were managed in various settings for ruptured intracranial aneurysms that caused subarachnoid haemorrhage. The predictor items are readily derived at hospital admission. The web based SAHIT prognostic calculator (http://sahitscore.com) and the related app could be adjunctive tools to support management of patients. IntroductionSubarachnoid haemorrhage from a ruptured intracranial aneurysm (SAH) is a relatively uncommon but severe subtype of stroke that is associated with a sudden dramatic onset in otherwise apparently healthy individuals and often results in poor outcomes. On average, a third of affected individuals do not survive; at least one in five of those who do survive are unable to regain functional independence.1 SAH is unlike the more common ischaemic stroke as it affects younger adults (median age 55) and therefore results in disproportionately many years of lost productive life.1 2 Predicting the outcome of this condition can be challenging given the considerable heterogeneity in the characteristics of affected individuals and their clinical course and variability in morphology of the aneurysm. Reliance on clinical intuition alone might be insufficient for accur...

Initial pupil status is a strong predictor for in-hospital mortality after aneurysmal subarachnoid hemorrhage

“…Other recently published aSAH prognostic models which were based on large-scale aSAH-cohorts include the SAFIRE scale, FRESH score and different scores based on the SAHIT cohort [26][27][28] . The SAFIRE model predicted poor functional outcome with an AUROC of 0.73 in the validation cohort and was based on aneurysm size, age, Fisher grade and WFNS 26 .…”

“…External validation was performed for functional outcome measured by Modified Rankin Scale after 3 months and yielded an AUROC of 0.769. With regards to mortality prediction after 2-12 months, the SAHIT models demonstrated AUROC of 0.76-0.78 and included age, hypertension and WFNS as well as in expanded variations also neuroimaging information and treatment modalities 28 .…”

Complement C5 Contributes to Brain Injury After Subarachnoid Hemorrhage

“…Poor functional outcome after SAH can partially be predicted using models that include factors such as age, World Federation of Neurological Surgeons (WFNS) scale at admission, and premorbid history of hypertension [5]. However, these models do not take into account the inflammatory response after SAH, which is considered to play a key role in the pathogenesis of early brain injury and delayed cerebral ischemia after aneurysmal SAH [6,7].…”

Haptoglobin genotype and aneurysmal subarachnoid hemorrhage

“…1 The strongest predictor of long-term outcome is the World Federation of Neurological Surgeons (WFNS) grade, 2 but it explained only 12% of the variance in outcome as determined by the Glasgow Outcome Scale (GOS) 3 in the largest study of outcome prediction in aSAH. 4 Some studies have suggested that haptoglobin (HP) genotype may also influence outcome, [5][6][7][8][9] but results are conflicting. 10 A recent meta-analysis found that the HP2 allele was associated with a worse short-term but not long-term outcome.…”