The MEssaging for Diabetes Intervention Reduced Barriers to Medication Adherence Among Low-Income, Diverse Adults With Type 2

Abstract

Background: Nonadherence to diabetes medication is prevalent and costly. MEssaging for Diabetes (MED), a mobile health (mHealth) intervention, identified and addressed user-specific barriers to medication adherence. We assessed whether MED reduced users' targeted barriers and if barrier reductions were associated with within-participant improvements in adherence or glycemic control (HbA1c).

Methods: Adults (N = 80) with type 2 diabetes completed self-report measures identifying barriers to adherence at baseline and monthly for 3 months. At each assessment, 17 barriers were assessed and ranked for each user. Each subsequent month, users received daily text messages addressing their 3 highest ranked barriers. Targeted barriers were different for each participant and could change monthly. Paired t-tests assessed within-participant improvement in targeted barriers each month, and nested regression models assessed if changes in a participant's barrier scores were associated with improvements in adherence and HbA1c.

Results: Participants were 69% non-white and 82% had incomes <$25K. Average HbA1c was 8.2 ± 2.0%. Assessment completion rates were 100% at baseline, 59% at 1 month, 30% at 2 months, and 65% at 3 months. The most commonly reported barriers were the cost of medications (76%), believing medications are harmful (58%), and lacking information about medications (53%). Participants' barrier scores improved each month and barrier improvement predicted adherence assessed via nightly adherence assessment text messages ( P < .001). Among participants who completed assessments each month, barrier improvement in months 2 and 3 ( P < .05) predicted HbA1c improvement.

Conclusions: Iterative, individual tailoring may overcome users' barriers to adherence. Attrition is a challenge for mHealth interventions among low-income patients.

Keywords: intervention; mHealth; medication adherence; mobile phone; text message; type 2 diabetes.

Figure 1.

Barriers to diabetes medication adherence assessed and the number of participants (out of 80) who received text messages targeting the barrier at any point during MEssaging for Diabetes.

Figure 2.

Changes in standardized scores for the top 3 barriers to diabetes medication adherence addressed by the intervention each month. Paired (within-participant) t-tests assessed changes in barrier scores for the 3 barriers addressed during each month of the intervention, and included all participants who completed an assessment at the starting time and a follow-up assessment with the next 2 months (eg, change from baseline to month 1 included participants who completed a follow-up assessment at month 1 or month 2, and so on). Higher scores indicated a barrier was more of a problem. Δ indicates the average within-participant change in standardized barrier scores (possible standardized scores range 0-20); standard error bars indicate standard errors of within-participant differences. *P < .05. **P < .01. ***P < .001.