Stroke is the third leading cause of death in Canada and the leading cause of adult neurological disability. The toll of stroke is not simply due to a direct injury to brain tissue. Three common comorbidities affect survival, quality of life, function and may affect recurrence after a stroke: depression, obstructive sleep apnea (OSA) and cognitive impairment ("DOC" co-morbidities). Each of these three conditions affects 30% to 50% of patients after a stroke.
We have developed a single, integrated, evidence-based tool (the DOC screen) to facilitate efficient identification of patients at very high risk, and those at very low risk, for all three complex outcomes. We have screened more than 1500 patients, and compared screening results to detailed testing used by specialists to diagnose these conditions in 439 volunteers. We have shown that the screen is both feasible and valid: 89% of patients can be screened in 5 minutes or less.
Depression, sleep problems and cognitive impairment are not necessarily "yes/no" problems. Thus, screening tests cannot be used as a diagnosis. Rather, the results of this screen can be used to identify people as high-, intermediate- or low-risk for each DOC condition. No screen should be used as diagnostic test or as a substitute for clinical judgement. For example, a score of 5 or less on DOC-cognition reflects a high risk of cognitive impairment, but does not assess whether there is a decline from a previous level of functioning, nor to impact on activities of daily living.
CIHR DOC Utility Research Study
The DOC screen will be routinely applied to all patients presenting to six high volume Regional Stroke Prevention Clinics (combined first visits >2,800 patients per year). Data will be abstracted from the patient chart using methodologies developed and validated in the Registry of the Ontario Stroke Network. We have REB approval to collect this data and to link with administrative datasets through the Institute for Clinical and Evaluative Sciences (ICES). We will use regression models to determine whether DOC screen scores add to baseline clinical and demographic data to predict the main negative outcomes. We hope to identify which patients presenting to TIA/stroke prevention clinics are at highest risk of adverse long-term events so focused interventions can be developed to improve survival, outcomes and function of stroke prevention clinic patients.
DOC Toolkit is an electronic web-based application designed to help health care professionals apply routine DOC screening, act on their screen and assess their performance. This website provides the health care professional with all the resources that they might need to implement routine screening in stroke prevention clinics. These resources include downloadable versions of the validated DOC screen, an instructional manual for administering the DOC screen, tools to assist in interpretation of screening results based on raw scores and demographic/clinical information and action documentation forms which auto-populate based on screening results.
The tool itself is knowledge translation device providing options and education to clinicians who use it. We are tracking the aggregated data on who is using the tool, how it is being used, the incidence of screening, the number of high-risk patients identified, and actions undertaken by clinicians over time for high-risk patients. No personal health information is being collected or stored. Using this information, we hope to better understand the barriers to screening, help clinicians audit current practices, identify gaps and areas for change to improve identification and treatment of Canadians with post stroke depression, obstructive sleep apnea and cognitive impairment.