A personalised intervention programme aimed at improving adherence to oral antidiabetic and/or antihypertensive medication in people with type 2 diabetes mellitus, the INTENSE study: study protocol for a randomised controlled trial

BACKGROUND: Medication non-adherence is a prevalent health problem in people with type 2 diabetes mellitus (T2DM). Interventions have previously been developed to improve medication adherence, but inconsistent outcomes have been reported. A potential explanation for this inconsistency is a ‘one size fits all’ approach, with interventions not tailored to the needs and preferences of individuals. Therefore, the aim of this study is to evaluate the effectiveness of a personalised intervention programme aimed at improving adherence to oral antidiabetic and/or antihypertensive medication in people with T2DM. METHODS: A parallel-group randomised controlled trial will be conducted in 40–50 community pharmacies in the Netherlands and the United Kingdom (UK). A total of 300 participants will be included and followed up for a period of 6 months. Participants will be people with T2DM identified as non-adherent to oral antidiabetic and/or antihypertensive medication, aged 35–75 years and mobile phone users. The intervention group will receive a personalised intervention programme that is based on one or more of the participants’ pre-defined non-adherence profile(s), namely (I) Knowledge and perceptions, (II) Practical problems, (III) Side effects and (IV) Negative mood and beliefs. The intervention comprises of one or more supporting modules, namely (I) Brief messaging, (II) Clinical medication review, (III) Medication schedule, (IV) Reminding messaging, (V) Medication dispensing systems, (VI) Smart messaging, (VII) Referral to general practitioner and (VIII) Unguided web-based Self Help Application for low mood. The control group will receive usual care including access to a publicly available informative diabetes website. The primary study outcome is medication adherence measured with a telephone pill count. Secondary outcomes are systolic blood pressure, HbA1c level, self-reported medication adherence, attitude and beliefs toward medication, satisfaction with diabetes treatment, health status and medical consumption and productivity cost. In addition, a process evaluation will be undertaken to establish the fidelity, reach and the extent to which intervention delivery is normalised in the daily practice of community pharmacy teams. DISCUSSION: The study can lead to a personalised intervention programme that improves medication adherence in people with T2DM that are non-adherent to oral antidiabetic and/or antihypertensive medication. TRIAL REGISTRATION: Dutch Trial Register, Trial NL8747, registered 02 July, 2020; ISRCTN Registry, ISRCTN36009809, registered 05 February, 2020. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13063-022-06491-7.