LO79: Patient-centred outcomes with use of CT angiography in patients presenting with acute stroke and TIA: a systematic review and meta-analysis

Abstract

Introduction: It remains unclear whether widespread use of computed tomography angiography (CTA) in acute strokes and transient ischemic attacks (TIAs) has tangible benefits for patient outcomes or management. We conducted a systematic review and meta-analysis of observational studies and randomized controlled trials (RCTs) investigating the use of CTA and patient-important outcomes (recurrent stroke, mortality, disability, and emergency department (ED) revisits) or changes in management in patients presenting with acute stroke or TIA. PROSPERO: 349590 Methods: MEDLINE, EMBASE, and the Cochrane Registry were searched through May 24, 2016 for eligible trials. We included observational cohort studies and RCTs evaluating use of CTA against a control group for outcomes of interest in patients presenting acutely with suspected stroke or TIA. Two independent reviewers extracted data and assessed study quality using the Newcastle Ottawa Scale. Data for mortality and stroke rate were pooled by the generic inverse variance method and expressed as risk ratios (RRs) with 95% confidence intervals (95% CI). Data for disability were reported as the mean difference (MD) and 95% CI. Heterogeneity was assessed using the Cochran’s Q statistic and quantified by the I² statistic. Overall strength of the evidence was assessed by the GRADE approach. Results: Three observational cohort studies involving 979 patients over an average of 1 year follow up met inclusion criteria; there were no eligible RCTs. CTA use in acute stroke or TIA patients was associated with a decreased mortality rate (RR=0.55, 95% CI 0.33 to 0.91, P=0.02; P_het=0.88, I²=0%). No changes were detected in stroke rate (RR=0.84, 95% CI 0.40 to 1.73, P=0.63; P_het=0.79, I²=0%). One study with data for disability showed no changes in mRS (MD=0.01, 95% CI -0.70 to 0.73, P=0.97). There were no eligible studies with data for ED revisits or changes in management. The strength of the evidence was assessed as very low quality due to imprecision for mortality, stroke rate, and disability. Conclusion: CTA use was associated with significantly reduced mortality in acute stroke and TIA patients, possibly due to confounding from poor baseline status of patients not receiving CTA. No significant changes were found for stroke rate or disability. There is a need for RCTs to confirm the effects of CTA use on patient outcomes and management.