Dulce Digital: An mHealth SMS-Based Intervention Improves Glycemic Control in Hispanics With Type 2 Diabetes

Abstract

Objective: Type 2 diabetes is growing in epidemic proportions and disproportionately affects lower-income, diverse communities. Text messaging may provide one of the most rapid methods to overcome the "digital divide" to improve care.

Research design and methods: A randomized, nonblinded, parallel-groups clinical trial design allocated N = 126 low-income, Hispanic participants with poorly controlled type 2 diabetes to receive the Dulce Digital intervention or usual care (UC). Dulce Digital participants received up to three motivational, educational, and/or call-to-action text messages per day over 6 months. The primary outcome was HbA1c; lipids, blood pressure, and BMI were secondary outcomes. Satisfaction and acceptability were evaluated via focus groups and self-report survey items.

Results: The majority of patients were middle-aged (mean age 48.43 years, SD 9.80), female (75%), born in Mexico (91%), and uninsured (75%) and reported less than a ninth-grade education level (73%) and mean baseline HbA1c 9.5% (80 mmol/mol), SD 1.3, and fasting plasma glucose 187.17 mg/dL, SD 64.75. A statistically significant time-by-group interaction effect indicated that the Dulce Digital group achieved a significantly greater reduction in HbA1c over time compared with UC (P = 0.03). No statistically significant effects were observed for secondary clinical indicators. The number of blood glucose values texted in by participants was a statistically significant predictor of month 6 HbA1c (P < 0.05). Satisfaction and acceptability ratings for the Dulce Digital intervention were high.

Conclusions: Use of a simple, low-cost text messaging program was found to be highly acceptable in this sample of high-risk, Hispanic individuals with type 2 diabetes and resulted in greater improvement in glycemic control compared with UC.

Trial registration: ClinicalTrials.gov NCT01749176.

© 2017 by the American Diabetes Association.

Figures

Figure 1

CONSORT flow diagram. appts, appointments.

Figure 2

A: HbA1c means and 95% CIs for the Dulce Digital and UC groups at baseline, month 3, and month 6. B: Association between the number of blood glucose values texted in by participants with a change in HbA1c level from baseline to month 6 in the Dulce Digital group. Values adjacent to error bars represent the mean number of texts for each quintile. Note: The texting variable was analyzed as a continuous variable but was binned into quintiles for graphical presentation. Although HbA1c change is represented on the y-axis for ease of interpretation, the month 6 HbA1c level was used as the outcome variable (with control for baseline HbA1c level) in regression analyses. Because of the curvilinear appearance of this relationship, the texting predictor was also examined using a quadratic term; however, the quadratic variable was not statistically significant.