Overview

The goal of this clinical trial is to determine the effectiveness of a novel mobile health-based habit formation intervention for increasing and maintaining adherence to anti-hypertensive (AH) medication among people living with hypertension and indicate medication nonadherence. The main questions it aims to answer are:

• Can daily incentives for AH pill taking increase and maintain AH medication adherence, control blood pressure, and reduce healthcare utilization and costs?
• Can daily incentives for AH pill taking, combined with action planning (e.g., "After I drink my morning coffee, I will take my medication.") increase and maintain medication adherence, control blood pressure, and reduce healthcare utilization and costs?
• What aspects of daily incentives and/or action planning do participants find most helpful or effective for AH medication adherence?
• What barriers exist for participants who receive daily incentives and/or action planning?

Researchers will compare three study groups: those who only receive daily incentives for the AH pill taking, those who receive daily incentives for AH pill taking combined with action planning, and a control group (who do not receive daily incentives for AH pill taking or action planning). By comparing these three groups, the researchers will be able to determine the effectiveness of the daily incentives with or without action planning for promoting long-term AH medication adherence, reduce healthcare costs, and improve blood pressure.

Participants will:

• Complete 5 online surveys over the course of 2 years (baseline, month 4, month 8, month 12, month 24).
• Submit blood pressure reading for 7 consecutive days after each survey timepoint.
• Submit photo evidence of their AH pill taking for 4 months (intervention groups only).

The highest- and lowest-performing participants in each intervention group will also be invited to complete a 30-minute interview to identify additional factors that contributed to either successful or unsuccessful completion of the intervention.

Eligibility

Eligibility Criteria:

• Aged 18 years or older
• Currently diagnosed with hypertension (either stage I or stage II hypertension)
• Able to read/write/understand English
• Have daily access to a smartphone
• Engaged in hypertension care: Already been prescribed hypertension medication for a minimum of 12 months at the time of study enrollment
• Demonstrated AH medication nonadherence by having over 73 days without documented AH medication prescription coverage (observable in Arizona Health Care Cost Containment System (AHCCCS) prescription drugs claims) in the past 12 months (i.e. \<80% mean adherence)