Secondary prevention of stroke in Saskatchewan, Canada: hypertension control

In the province of Saskatchewan, Canada, stroke is the third leading cause of death as well as the major cause of adult disability. Once a person suffers a stroke or transient ischemic attack (TIA), they are at high risk for having a secondary stroke. Hypertension (elevated blood pressure) is the single most important modifiable risk factor for both first and recurrent stroke, and is thus an important risk factor to be controlled. According to the Canadian Stroke Strategy (CSS) Best Practice Recommendations, blood pressure lowering treatment should be initiated before discharge from hospital for all stroke/TIA patients. The purpose of this study was to examine the quality of medically driven secondary stroke prevention care in Saskatchewan as applied to hypertension control.

The objectives of the study were to: (1) develop methodology and calculate a secondary stroke process of care measure using available data in Saskatchewan, based on an appropriate hypertension therapy indicator recommendation from the CSS Performance Measurement Manual; (2) examine variation in secondary stroke prevention hypertensive care among the Saskatchewan Regional Health Authorities; and (3) investigate factors associated with receiving evidence-based hypertensive secondary stroke prevention.

This multi-year cross-sectional study was an analysis of deidentified health data derived from linkage of administrative health data. A select indicator from the CSS Performance Measurement Manual that measures adherence to a CSS Best Practice Guidelines concerning use of antihypertensive medications for secondary stroke prevention was calculated. Logistic regression was used to quantify the association of patient demographic and socioeconomic characteristics and geographic location of care with receipt of guideline-recommended hypertensive secondary stroke prevention. The target population was all Saskatchewan residents who were hospitalized in Saskatchewan for a stroke or TIA between April 1, 2001 and March 31, 2008.

The results of this study indicate that the management of hypertension for secondary stroke prevention is sub-optimal in Saskatchewan. Although there was some improvement over the time period, approximately 40% of patients were not taking antihypertensives at 90 days after discharge from acute care. The correlates, urban/non-urban, previous use of antihypertensive drugs and effect of age modified by sex, were found to be significantly associated with receiving hypertensive secondary stroke prevention, suggesting there are modifiable factors that contribute to variations in this form of secondary stroke care quality in Saskatchewan.

The results of this study suggest that there is a need for province-wide improvement to secondary stroke prevention in Saskatchewan, Canada.