Interventions for improving modifiable risk factor control in the secondary prevention of stroke

People with stroke or transient ischaemic attack (TIA) are at increased risk of future stroke and other cardiovascular events. Stroke services need to be configured to maximise the adoption of evidence-based strategies for secondary stroke prevention. Smoking-related interventions were examined in a separate review so were not considered in this review. This is an update of our 2014 review.

To assess the effects of stroke service interventions for implementing secondary stroke prevention strategies on modifiable risk factor control, including patient adherence to prescribed medications, and the occurrence of secondary cardiovascular events.

We searched the Cochrane Stroke Group Trials Register (April 2017), the Cochrane Effective Practice and Organisation of Care Group Trials Register (April 2017), CENTRAL (the Cochrane Library 2017, issue 3), MEDLINE (1950 to April 2017), Embase (1981 to April 2017) and 10 additional databases including clinical trials registers. We located further studies by searching reference lists of articles and contacting authors of included studies.

We included randomised controlled trials (RCTs) that evaluated the effects of organisational or educational and behavioural interventions (compared with usual care) on modifiable risk factor control for secondary stroke prevention.

Four review authors selected studies for inclusion and independently extracted data. The quality of the evidence as 'high', 'moderate', 'low' or 'very low' according to the GRADE approach (GRADEpro GDT).Three review authors assessed the risk of bias for the included studies. We sought missing data from trialists.The results are presented in 'Summary of findings' tables.

The updated review included 16 new studies involving 25,819 participants, resulting in a total of 42 studies including 33,840 participants. We used the Cochrane risk of bias tool and assessed three studies at high risk of bias; the remainder were considered to have a low risk of bias. We included 26 studies that predominantly evaluated organisational interventions and 16 that evaluated educational and behavioural interventions for participants. We pooled results where appropriate, although some clinical and methodological heterogeneity was present.Educational and behavioural interventions showed no clear differences on any of the review outcomes, which include mean systolic and diastolic blood pressure, mean body mass index, achievement of HbA1c target, lipid profile, mean HbA1c level, medication adherence, or recurrent cardiovascular events. There was moderate-quality evidence that organisational interventions resulted in improved blood pressure control, in particular an improvement in achieving target blood pressure (odds ratio (OR) 1.44, 95% confidence interval (CI) 1.09 to1.90; 13 studies; 23,631 participants). However, there were no significant changes in mean systolic blood pressure (mean difference (MD), -1.58 mmHg 95% CI -4.66 to 1.51; 16 studies; 17,490 participants) and mean diastolic blood pressure (MD -0.91 mmHg 95% CI -2.75 to 0.93; 14 studies; 17,178 participants). There were no significant changes in the remaining review outcomes.

We found that organisational interventions may be associated with an improvement in achieving blood pressure target but we did not find any clear evidence that these interventions improve other modifiable risk factors (lipid profile, HbA1c, medication adherence) or reduce the incidence of recurrent cardiovascular events. Interventions, including patient education alone, did not lead to improvements in modifiable risk factor control or the prevention of recurrent cardiovascular events.