The impact of pharmacy care and motivational interviewing on improving medication adherence in patients with cardiovascular diseases: A systematic review of randomised controlled trials

Background Cardiovascular disease (CVD) is prevalent worldwide, and for many patients, non-adherence to medication remains a problem. Motivational interviewing is a behavioural, communication strategy used as an intervention aimed to improve health outcomes. Aims This systematic review sought to investigate the effect of motivational interviewing delivered as part of pharmacy care on medication adherence, and the effect this has on clinical outcomes. These included systolic and diastolic blood pressure, haemoglobin A1C, lipid profiles and cardiovascular risk scores. Method A systematic review was conducted in six databases: PubMed Central UK, Cochrane Library, CINAHL (EBSCO), PsycINFO, EMBASE and MEDLINE from the inception of motivational interviewing in 1983 to November 2020. Randomised controlled trials (RCTs) that assessed motivational interviewing as part of pharmacy care interventions were selected. The Cochrane risk of bias tool was used to assess the risk of bias for each included study. This review was registered with PROSPERO (registration number CRD42020222954). Results A total of eight RCTs met the inclusion criteria. Five out of eight studies demonstrated medication adherence significantly improved following motivational interviewing interventions. One study showed a significant improvement for systolic blood pressure change by 7.2 mmHg (95% CI 1.6-12.8 mmHg); this reduction was observed in patients whose baseline blood pressure was above their target blood pressure. No statistically significant effect was seen across other clinical outcomes. Conclusion Motivational interviewing could be an effective behavioural strategy to enhance medication adherence in patients with CVD. Although the evidence is promising thus far, further research is required to explore the impact of motivational interviewing on clinical outcomes as well as the feasibility of implementing motivational interviewing interventions within existing pharmacy care services.