No significant change for the primary objective at 12 months

Nearly half of the adult population in Latin American urban settings has abnormally high blood pressure. Although half of these subjects with high blood pressure are still in the pre-hypertensive stage (systolic blood pressure values in the 120-139 mmHg range or diastolic blood pressure in the 80-89 mmHg range), the rate of progression to hypertension is high (10-20% per year), according to studies done in other settings. The main objective of this proposal is to evaluate the effectiveness of an affordable and sustainable primary health care intervention to reduce blood pressure and prevent progression from pre-hypertensive status to hypertension in individuals at poor urban clinics in Argentina, Guatemala, and Peru. Our primary hypotheses are that pre-hypertensive subjects who receive mHealth (mobile health) support for 12 months (intervention group) will have lower blood pressure compared to individuals who receive the usual primary health care (control group); and that pre-hypertensive subjects will maintain lower blood pressure six months after receiving mHealth support. The investigators will determine the effects of an intervention using mHealth technology, including short message services (SMS) and one-to-one telephone calls, to promote lifestyle modification focused on reducing blood pressure among participants. The intervention also aims to help participants become better informed, motivated, and encouraged to practice self-management of their own health; to improve patient satisfaction levels; provide tailored targeted interventions; and to improve patient-provider relationships. The proposal is designed as a proof-of-concept intervention in three Latin American countries that encompass a wide range of environments and health care settings. A total of 212 subjects (30-60 years old) per country will be recruited in primary health clinics and randomized to study groups. Blood pressure, anthropometry, and behavioral risk factors (physical activity, diet, stress, alcohol and tobacco use) will be measured at baseline and at months 6 and 12 during the intervention, and six months after the end of the intervention. The investigators will also evaluate feasibility, acceptability, cost-effectiveness, and process implementation of the intervention.

Inclusion Criteria:

• Systolic blood pressure values in the 120-139 mmHg range or diastolic blood pressure in the 80-89 mmHg range
• No current anti-hypertensive medication
• Own a personal cellular phone

Exclusion Criteria:

• Previous diagnosis/treatment hypertension
• Illiteracy
• Another household member already in the study

1 year