JMIR Publications

ABSTRACT

Background:

The evidence-based National Diabetes Prevention Program (NDPP) is now widely disseminated, yet strategies to optimize outcomes are needed, especially for underserved populations. Virtual modalities hold promise, for which supplemental in-person coaching is beneficial. Conversely, benefits of supplementing the NDPP with virtually-delivered content are unknown. We previously demonstrated efficacy of a stand-alone text messaging intervention based on the NDPP curriculum (SMS4PreDM) in a randomized controlled trial. Then, upon broader dissemination of SMS4PreDM, we showed that the intervention was relatively low-cost to deliver and demonstrated high retention albeit with modest weight loss compared to observation-only controls.

Objective:

To determine potential benefits of enhancing NDPP delivery with text message support, here we compare effectiveness of NDPP with and without supplementary SMS4PreDM in a safety net healthcare system.

Methods:

As of October 2015, patients with diabetes risks were identified primarily from provider referrals and enrolled in NDPP classes and/or SMS4PreDM per their preference. All SMS4PreDM participants received messages promoting lifestyle change and modest weight loss, delivered six days per week for 12 months. Content followed the NDPP session schedule for concordance with topics of face-to-face classes. To evaluate effectiveness of NDPP with supplemental support, this analysis compares 236 participants who received both NDPP and SMS4PreDM with 252 NDPP-only participants. Differences in characteristics between intervention groups were assessed using chi-square and t-tests. Differences in NDPP attendance and weight loss outcomes (based on first/last weights collected at NDPP sessions) were analyzed with multivariable linear and logistic regression.

Results:

Among 488 participants, mean age was 50.4 (SD=13.9) and the majority were female (77.7%) and Hispanic (65.5%). An additional 19.1% were non-Hispanic white and 14.3% were non-Hispanic black. Participants who chose supplemental text message support were 5.7±1.2 years younger on average (P<.001) than those preferring in-person classes only. Relatively more women and Hispanics enrolled in the NDPP with supplemental text messages than in NDPP classes only, 83.9% vs. 71.6% (P<.01) and 74.0% vs 58.3% (P<.001), respectively. While NDPP participants who received supplemental text messages appeared to achieve greater weight loss than those who did not (2.1% vs 1.7%), this difference was not significant (P=.373). Attendance and other outcomes were comparable between groups.

Conclusions:

Supplemental text message support appeared to appeal relatively more to women, Hispanics, and younger individuals than others. Yet, extra costs of supplemental text message support ($100.92 per participant) may be unwarranted without sufficient return on investment via greater attendance and weight loss in the NDPP. Participants receiving both in-person and virtual content attended classes equally, despite remote access to content. Text messaging may continue to have appeal to address problematic retention in yearlong, in-person classes, contrasted with high retention previously shown for SMS4PreDM participants.