Challenges of Implementing mHealth Interventions for Lifestyle Modification in Prehypertensive Subjects in Argentina, Guatemala, and Peru

The present study describes the processes related to the implementation of mHealth interventions for lifestyle modification in a randomized controlled trial conducted with prehypertensive subjects in Argentina, Guatemala, and Peru from low-resource settings. In the intervention group, participants received, during the course of a year, a monthly counseling call from a trained caller and a one-way weekly tailored short message service (SMS) to promote lifestyle modification. We evaluated reach, fidelity, dose, and attrition to assess how the intervention was implemented. 637 prehypertensives were included in the study, 321 in the control and 316 in the intervention group. Fifty-three percent were women with a mean age of 43.4 ± 8.4 years. Ninety-eight percent of the participants assigned to the mHealth arm were reached. The mean number of calls that had to be made to conduct a counseling call in prehypertensive subjects was 3.29 ± 1.55 (3.15 ± 1.54 in Argentina, 2.58 ± 0.96 in Guatemala and 4.12 ± 1.65 in Peru). The overall median number of counseling calls was six (IQR 4-8) with no differences observed across the countries. With regard to SMS, 58.3 % of the participants reported that they received the SMS. Attrition rate was 13 % (24 % in Argentina, 10.5 % in Guatemala, and 4.7 % in Peru). The delivery of the intervention was challenging in the three countries with differences among them in process results. Process evaluation methods and metrics are useful to assess whether the intervention program was delivered as planned.