Interventions supporting long term adherence and decreasing cardiovascular events after myocardial infarction (ISLAND): pragmatic randomised controlled trial

Abstract

Objective: To test a scalable health system intervention to improve long term adherence to secondary prevention treatments among patients who have had a recent myocardial infarction.

Design: Three arm, pragmatic randomised controlled trial with blinded outcome assessment.

Setting: Nine cardiac centres in Ontario, Canada.

Participants: 2632 patients with obstructive coronary artery disease after a myocardial infarction, identified from a centralised cardiac registry.

Interventions: Participants were randomised 1:1:1 to receive usual care, five mail-outs developed through a user centred design process, or mail-outs plus phone calls. The phone calls were delivered first by an interactive automated system to screen for non-adherence to treatment. Trained lay health workers followed up as necessary. Interventions were coordinated centrally but delivered from each patient's hospital site.

Main outcome measures: Co-primary outcomes were completion of cardiac rehabilitation and adherence to recommended medication. Data were collected by blinded assessors through patient report and from administrative health databases at 12 months.

Results: 2632 patients (mean age 66, 71% male) were randomised: 878 to the full intervention (mail plus phone calls), 878 to mail only, and 876 to usual care. Of the respondents, 174 (27%) of 643 in the usual care group, 200 (32%) of 628 in the mail only group, and 196 (37%) of 531 allocated to the full intervention completed cardiac rehabilitation (adjusted odds ratio 1.55, 95% confidence interval 1.18 to 2.03). In the mail plus phone group, 11.7%, 6.0%, 14.4%, 32.9%, and 35.0% reported adherence to 0, 1, 2, 3, and 4 drug classes after one year, respectively, in comparison with 12.5%, 6.8%, 13.6%, 30.2%, and 36.8% in the mail only group, and 12.2%, 8.4%, 13.1%, 30.3%, and 36.1% in the usual care group, respectively (mail only v usual care, odds ratio 0.98, 95% confidence interval 0.81 to 1.19; full intervention v usual care, 0.99, 0.82 to 1.20).

Conclusions: Scalable interventions delivered by mail plus phone can increase completion of cardiac rehabilitation after myocardial infarction but not adherence to medication. More intensive interventions should be tested to improve adherence to medication and to evaluate the association between attendance at cardiac rehabilitation and adherence to medication.

Trial registration: ClinicalTrials.gov NCT02382731, registered 9 March 2015 before any patient enrolment.

Conflict of interest statement

Competing interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf and declare: support from MOHLTC for the submitted work; NMI declares support from the Canadian Institutes of Health Research and MOHLTC and the Ontario Strategy for Patient-Oriented Research Support Unit during the conduct of the study, and now holds a Canada Research Chair (tier 2) in implementation of evidence based practice, as well as a clinician scholar award from the University of Toronto Department of Family and Community Medicine; TM and JC declare support from MOHLTC during the conduct of the study; CA declares grants from the Heart and Stroke Foundation, outside the submitted work; JMG is supported by a Canada Research Chair in knowledge transfer and uptake, outside the submitted work; HOW is supported by a Fonds de recherche du Quebec-Santé research scholar junior 1 award, outside the submitted work; NS receives support from Western University’s Department of Medicine’s programme of experimental medicine, outside the submitted work; the other authors declare no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; and no other relationships or activities that could appear to have influenced the submitted work.

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