Testing Feasibility of Medication Adherence Problem Solving for Hypertension

Improving rates of blood pressure (BP) control among adults with hypertension is a key step in reducing rates of myocardial infarction, stroke, and heart failure, and lowering overall mortality from cardiovascular disease. Unfortunately, over half of patients prescribed medication for hypertension do not take their medication as prescribed, leading to a high percentage of patients (45%) who are unable to reach their target BP despite being treated with antihypertensive medication. Low medication adherence has been linked with higher rates of myocardial infarction, stroke, and angina, as well as reduced life expectancy. Previously tested interventions to improve adherence to antihypertensive regimens have had limited efficacy, largely due to an underlying assumption that a single, standardized intervention approach will address all patients' reasons for nonadherence. Tailoring adherence interventions using a Managed Problem Solving approach will permit addressing each patient's reasons for nonadherence. This project will test the feasibility of the Medication Adherence Problem Solving for Hypertension (MASH) telehealth intervention, tailored to each participant's reasons for low adherence to their antihypertensive medication. The intervention is designed to assess beliefs about hypertension, beliefs about medications, and barriers to effective medication-taking We will then deliver intervention strategies to address each patient's problematic beliefs and barriers, applying the 5 steps of Managed Problem Solving. The proposed project aims are to 1) Assess the feasibility of MASH to improve antihypertensive medication adherence among adults with hypertension (HTN) by tracking recruitment, participant engagement and satisfaction with the intervention, as well as retention in the study; 2) Obtain estimates of efficacy of MASH compared to usual care on improving antihypertensive adherence as measured by electronic monitoring caps (MEMS) and lowering BP among persons with elevated BP at baseline over 12 weeks to inform future power analyses for a full-scale trial; and 3) Obtain estimates of other model parameters necessary to inform future power analyses for a full-scale intervention trial, including (a) intervention effects on targeted reasons for nonadherence (beliefs, barriers, perceived side-effects) and their subsequent association with medication adherence; (b) strength of covariate effects (e.g. education, household size, employment); and (c) the within-participant correlation between assessments. If successful, this intervention can also serve as a model for improving medication adherence in other chronic conditions and improve health outcomes for the half of patients with chronic conditions who struggle to manage their medications.

Inclusion criteria

• Aged ≥ 18 years at time of study entry
• Able to read, write, and converse in English
• Have an active prescription for at least one HTN medication, reporting no antihypertensive prescription changes for 30 days prior to study entry
• Have prescription drug coverage or participate in a prescription assistance program that covers medication costs.
• Diagnosis of HTN, based on self-report or confirmed through medical records, where available. (Self-reported high BP has long been shown to be strongly correlated with presence of a HTN diagnosis.22-24 Self-report combined with presence of a prescribed HTN medication ensures that only participants with HTN will be included)
• Must self-administer their own medications
• Uncontrolled BP: systolic (SBP) ≥ 130 mmHg and/or diastolic (DBP) ≥ 80 mmHg at baseline
• Nonadherent to HTN medication (Hill-Bone Medication Subscale score < 36) at screening

Exclusion criteria

• Acutely ill (e.g., symptoms of myocardial infarction, respiratory distress, stroke)
• Patients who have end-stage renal disease (ESRD) and/or are on dialysis
• In state of hypertensive crisis (SBP >180 and/or DBP > 120 mmHg) at the time of study screening. Any participant in hypertensive crisis will be referred to their health care provider immediately for further instruction and follow-up, per current guidelines2
• BP measurement is contraindicated on both upper extremities
• Terminal chronic illness with a life expectancy of 6 months or less