mHealth, texting, medication adherence, hypertension

Introduction: Non-communicable chronic diseases have a great impact on the health system and, among them, systemic arterial hypertension is the most prevalent, being associated with high socioeconomic costs, represented by the high rates of hospitalizations in the Unified Health System (SUS) , due to the loss of work productivity and family income. Despite its diagnosis being considered easy and the broad therapeutic arsenal available, effective blood pressure control and maintenance of the therapeutic regimen have been difficult due, among other factors, to non-adherence to treatment. Although several interventions have been developed to improve adherence to medication treatment, no high-quality evidence was found to support the use of a specific intervention. However, recently, studies have shown that sending text messages (Short Message Service - SMS) as reminders or patient engagement messages has increased adherence to the treatment of patients with chronic diseases, requiring, however, to be deepened through other designs. Objective: The ESSENCE study evaluated the effect of sending text messages with and without a reminder of the time of medication use on adherence to medication treatment and on the reduction of blood pressure in hypertensive patients. Methods: This is a randomized, cross-over, double-blind clinical trial with active control, which included hypertensive patients, aged between 30 and 69 years, monitored at a public community pharmacy. The messages were sent automatically by software and received on the participants' cell phones. Group 1 included patients who received informational text messages about antihypertensives and hypertension control for 90 days. Group 2 included patients who received informational messages associated with reminder messages at the time of each drug dose for 90 days. After a 30-day washout period, the groups were switched and received the interventions for another 90 days. Results: The 157 individuals evaluated had a mean age of 52(8.8) years and most were female (76.4%). No significant difference was found in self-reported adherence within and between groups in the pre- and post-crossover periods. For systolic and diastolic blood pressure, there was a significant reduction in the pre-crossover period, but with no difference when comparing groups. In the post-crossover period, the reduction was not significant in the intra and between groups analyses. Conclusion: Thus, it was possible to observe that there was equivalence of effect between the two interventions for the primary outcomes evaluated. The results point to the possibility of implementing messaging systems in health services.