JMIR Publications

Background:

Hypertension is a growing problem worldwide, markedly in low- and middle-income countries, where the rate of control slightly decreased. The overall prevalence of hypertension in Brazil is 28.7% among adult individuals and 68.9% in the population aged 60 years and older, and less than a third of patients have controlled blood pressure (BP). The use of technologies—mobile phones and the internet—to implement interventions to reduce blood pressure can minimize costs and diminish cardiovascular risk. Interventions through text messaging and electronic BP monitoring present divergent results.

Objective:

This trial evaluates the effectiveness of interventions—personalized messages and telemonitoring of BP—to reduce systolic BP and improve lifestyle compared to the usual care of patients with hypertension (control group).

Methods:

This factorial randomized controlled trial enrolls individuals aged 30 to 75 years who have a mobile phone and internet access with the diagnosis of hypertension under drug treatment with up to 2 medications and uncontrolled BP. Eligible participants should have both increased office BP and 24-hour BP with ambulatory BP monitoring. Participants with severe hypertension (systolic BP ≥180 or diastolic BP ≥110 mm Hg), life threatening conditions, low life expectancy, recent major cardiovascular event (last 6 months), other indications for the use of antihypertensive medication, diagnosis of secondary hypertension, pregnant or lactating women, or those unable to understand the interventions are excluded. Participants are randomly allocate to 1 of 4 experimental arms: (1) Telemonitoring of blood pressure (TELEM) group: receives an automatic oscillometric device to measure BP, (2) telemonitoring by text message (TELEMEV) group: receives personalized, standardized text messages to stimulate lifestyle changes and adhere with BP-lowering medication, (3) TELEM-TELEMEV group: receives both interventions, and (4) control group: receives usual clinical treatment (UCT). Data collection is performed in a clinical research center located in a referent hospital. The primary outcomes are reduction of systolic BP assessed by 24-hour ambulatory BP monitoring (primary outcome) and change of lifestyle (based on dietary approaches to stop hypertension (DASH)-type diet, sodium restriction, weight loss or control, increase of physical activity).

Results:

This study was funded by two Brazilian agencies: the National Council for Scientific and Technological Development and Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul. Enrollment was completed at the end of 2017 (N=231), the follow-up is ongoing, and data analysis is expected to begin in early 2019. A reduction of 24-hour systolic BP of approximately 8.8 [SD 13.1] mm Hg for participants in the BP monitoring group versus 3.4 [SD 11.6] mm Hg in the UCT group is expected. A similar reduction in the text messaging group is expected.

Conclusions:

The use of mobile technologies connected to the internet through mobile phones promotes time optimization, cost reduction, and better use of public health resources. However, it has not been established whether simple interventions such as text messaging are superior to electronic BP monitoring and whether both outperform conventional counseling.

ClinicalTrial:

ClinicalTrials.gov NCT03005470; https://clinicaltrials.gov/ct2/show/NCT03005470 (Archived by WebCite at http://www.webcitation.org/70AoANESu). Plataforma Brasil CAAE 31423214.0.0000.5327.

International Registered Report:

RR1-10.2196/9619