Abstract
Background
Transient Ischaemic Attacks (TIA) and minor strokes indicate a high risk of early recurrent stroke and other vascular events. Early implementation of secondary preventive measures provided through rapid access specialist stroke services reduces the 90-day stroke risk from 10% to 2%. Same day stroke specialist access is challenging in some areas due to resource constraints, geographical distances, or cultural barriers. The use of electronic decision support tools can help to improve guideline adherence and in some cases improve patient health outcomes and reduce treatment costs. This thesis explores the utility of a TIA/stroke electronic decision support tool in primary care to improve TIA/stroke care in New Zealand.
Methods
The intervention is a web-based electronic decision support tool that integrates into general practitioners’ practice management systems. This tool was developed by the candidate in collaboration with BPACINC. Four preliminary observational studies are reported. The focus of this thesis is a multi-centre, single-blind, parallel-group, cluster randomised, controlled trial comparing TIA/stroke electronic decision support guided TIA management with usual care in general practices. Eligible participants presented to a participating general practice with symptoms of TIA or stroke. Main outcomes were guideline adherence and 90-day stroke risk. Secondary outcomes included total cerebrovascular and vascular events or death, treatment cost, adverse events, and user feedback. The main analysis was by cluster-adjusted logistic regression.
Findings
The preliminary studies suggested that the tool was effective and safe, but their design limitations precluded definite conclusions. In the multi-centre trial 29 clinics were randomly assigned to the intervention group and 27 to the control group, recruiting 172 and 119 patients respectively. More patients received guideline adherent care in the intervention group 131/172 (76.2%), compared to the control, 49/119 (41.2%); adjusted odds ratio (OR) 4.57; 95% confidence interval (CI) 2.39-8.71; p<0.001. The 90-day stroke rates were 2/172 (1.2%) in the intervention and 5/119 (4.2%) in the control group; OR 0.27, 95%CI 0.05-1•41; p=0.098. The 90-day TIA and/or stroke rates were lower at 4/172 (2.0%) in the intervention compared with 10/119 (8.5%) in the control group; adjusted OR 0.26; 95%CI 0.70-0.97; p=0.045. There were also fewer, 6/172 (3.5%), vascular events or deaths in the intervention group compared with 14/119 (11.9%) in the control group; adjusted OR 0.27; 95%CI 0.09-0.78; p=0.016. Finally, the intervention was associated with a lower treatment cost ratio of 0.65 (95%CI 0.47-0.91; p=0.013) without an increase in adverse events. A pre-specified sub-group analysis looked at patients with specialist confirmed TIA/stroke and their 90-day stroke rate was 2/99 (2.2%) in the intervention and 5/69 (7.3%) in the control group; unadjusted OR 0.26; 95%CI 0.05 to 1.4; p=0.097. User-feedback from both general practitioners and stroke specialists was favourable.
Interpretation
Primary care use of a TIA/stroke electronic decision support tool improves guideline adherence, reduces the risk of recurrent cerebrovascular and vascular events, safely reduces treatment cost, and is well received by clinicians. With increasing health care complexity inter-sectorial collaboration and exploration of new management strategies are important. The TIA/stroke electronic decisions support software is an example of such collaboration and innovation. The journey from inspiration through implementation and rigorous scientific evaluation has been successful in demonstrating the utility of this tool for New Zealanders and perhaps beyond.