Effects of a Proactive Interdisciplinary Self-Management (PRISMA) program on medication adherence in patients with type 2 diabetes in primary care: a randomized controlled trial

Purpose: The present study aims to investigate the effect of the group-based Proactive Interdisciplinary Self-Management (PRISMA) training program on medication adherence in patients with type 2 diabetes (T2DM) treated in primary care. Patients and methods: The current study is a two-arm, parallel group, randomized, open label trial (1:1) of 6-month duration with a 6-month extension period in which both groups received the intervention (wait-list control). People 18 years old or older who were diagnosed with T2DM were included. The intervention consisted of two group meetings about T2DM guided by care providers. The control group received usual care only (visits at the general practice). The primary outcome was adherence based on pharmacy refill data and was measured using medication possession ratio (MPR). The secondary outcomes were the number of drug holidays and self-reported adherence, measured by the 5-item Medication Adherence Rating Scale (MARS-5). Results: Of the total sample (n=108), 66.6% were male. The mean age was 69.3 years (SD=9.1). In the 6-month period, patients were more adherent in the intervention group (n=56) (median MPR =100.0 [51.1-100.0]) than in the control group (n=52) (median MPR =97.7 [54.1-100.0]) (U=1,042, z=-2.783, P=0.005). The intervention group had less drug holidays than the control group (relative risk 0.55, 95% CI, 0.37-0.80). The sum scores of the MARS did not differ between the intervention group (median =23.98, SD=0.91) and the control group (median =24.00, SD=1.54). Conclusion: The PRISMA program resulted in a small improvement in MPR and fewer drug holidays, while no improvement has been found in self-reported adherence. However, health care providers and policy makers could take into account that adherence might be influenced by PRISMA.