Medication Adherence in Hypertensive Individuals With Bipolar Disorder

This study will test an adherence intervention (iTAB-CV) delivered via interactive text messaging which first targets behavioral intent and then adds cues/reminders and reinforcement to form the habit of taking antihypertensives in non-adherent individuals with BD. Thirty eight individuals with BD and HTN being treated with evidence-based antihypertensive agents and mood stabilizing or antipsychotic medications who are non-adherent with their HTN medicine will be enrolled.

This study uses a prospective cohort design with participants serving as their own control. Investigators will test the iTAB-CV intervention quantitatively for feasibility and acceptability as well as for efficacy in increasing adherence to antihypertensives, decreasing systolic blood pressure, and increasing adherence to BD medication.

All study participants will be followed for a 3-month period. iTAB-CV, delivered via mobile phone, is intended to be a brief adjunct to standard primary care and mental health treatment. All individuals will continue to receive treatment as usual with their regular provider(s). Individuals who meet eligibility criteria will have a 30 day run-in period in which their medication adherence will be measured with TRQ and MEMS but without an additional intervention. Following the run-in period, Stage 1 of the iTAB-CV intervention will be introduced. Researchers will conduct an interview in order to customize iTAB-CV for each participant at the baseline session. In the first month of iTAB-CV, participants will receive alternating daily texts with psychoeducational and motivational content once daily and a daily mood rating request to both monitor their mood and to determine engagement with the iTAB-CV intervention. In the second stage of iTAB-CV, participants will receive daily texts which will include medication reminders, contextual cues, and immediate reinforcement for medication taking behavior in addition to the content from stage 1.

Assessments that include evaluation of treatment adherence, psychiatric symptoms, self-efficacy for medication taking behavior, illness beliefs, medication attitudes, and habit strength for both antihypertensive and BD medications will be conducted at four time points over a 3-month time period (screening, baseline/week 4, week 8, and week 12). Blood pressure will be measured at each of the four contacts. Individuals who drop out of the intervention, and who agree, will be followed up with outcomes assessments over the same 3-month time period that they would have been evaluated had they remained in the study.

About one month after study completion, a member of the research team will call each participant and ask questions about their bipolar and blood pressure medication taking habits.

Inclusion criteria

• Participants will have a clinical diagnosis of BD for at least 2 years as determined by a standardized diagnostic interview, the Mini-International Neuropsychiatric Interview (MINI) (52)
• Have stage 1 or 2 HTN with a systolic pressure ≥130
• Carry a diagnosis of HTN per patient self-report ≥ 6 months prior to enrollment
• Have been prescribed at least one regularly scheduled antihypertensive medication for ≥ 3 months since diagnosis
• Have self-reported poor adherence to antihypertensive medication defined as at least 20% of days with missed doses for at least one antihypertensive in either the past week or past month as identified by the Tablets Routine Questionnaire (TRQ).
• Be able to participate in psychiatric interviews

Exclusion criteria

• Unable or unwilling to participate in psychiatric interviews. This will include individuals, who may be too psychotic to participate in interviews/rating scales
• Unable or unwilling to give written, informed consent to study participation
• Under the age of 21
• In the interest of patient safety, individuals who are at high immediate risk for suicide will be excluded from study participation. The suicide risk assessment will be informed by standardized assessments of psychiatric symptoms and the Mini-International Neuropsychiatric Interview (MINI). In the event that a potential study participant is determined to be at high risk for suicide, that individual will not be enrolled and the study staff will immediately implement procedures for the safety of the individual. Once such individuals are deemed stable, they may be once again considered for inclusion in the research.
• Individuals who are monolingual, non-English speaking will be excluded. Given the relatively small sample size in the proposed study, it would not be practical to conduct sub-group analyses. Also, the study assessment tools and the texting intervention are not available in other languages and would be impractical to develop. Based upon our BD adherence work, which drew upon a population similar to the proposed trial, there were no potential subjects who were excluded from the studies due to inability to speak English.
• Illiterate participants will be excluded because reading is an essential skill required to complete self-report questionnaires administered during the study as well as to respond to the text messages which make up the intervention.