Validation and comparison of two stroke prognostic models for in hospital, 30-day and 90-day mortality. (December 2017)

• Record Type: Journal Article
• Authors: Dutta, Dipankar; Cannon, Abigail; Bowen, Emily
• Is Part Of: European stroke journal. Volume 2:Number 4(2017)
• Page Start: 327
• Page End: 334
• Publication Date: 2017-12
• Subjects: Stroke -- prognostic score -- prognosis -- mortality; Cerebrovascular disease -- Periodicals; 616.8005
• DOI: 10.1177/2396987317703581
• Languages: English
• ISSNs: 2396-9873

Abstract

Introduction: We aimed to validate and compare two clinical prognostic models for mortality which include the National Institutes of Health Stroke Scale (NIHSS); the Age and NIHSS Score (ANS) and case mix model (CMM) of the Sentinel Stroke National Audit Program (SSNAP). The NIHSS on admission was also tested as a prognostic score. Patients and methods: Prospectively collected data from the SSNAP register for a cohort of patients (ischaemic and haemorrhagic stroke) admitted over 1 year to Gloucestershire Royal Hospital, England were accessed. The ANS and CMM were calculated and tested for in hospital, 30-day and 90-day mortality using calibration plots with Hosmer–Lemeshow tests, receiver operating characteristics curves and other measures of prognostic accuracy. Results: Of 848 patients, 110 (12.9%) died in hospital, 112 (13.2%) at 30 days and 164 (19.2%) at 90 days. Calibration for all three scores was good, although Hosmer–Lemeshow test p values were <0.05 with the NIHSS alone for in hospital and 30-day deaths, suggesting deviation from good fit. The c-statistics for in hospital, 30-day and 90-day mortality were ANS (0.783, 0.782, 0.779) and CMM (0.783, 0.774, 0.758), respectively. The NIHSS alone showed fair discrimination but performed less well. A NIHSS score ≥6 was associated with significant mortality ( p < 0.0001) in comparison to a score <6. Conclusion: A simple prognostic model containing age and admission NIHSS only, performed as well as a more complex score at predicting in hospital, 30-day and 90-day mortality. Admission NIHSS recording should be encouraged for stroke registries.