Improving Antihypertensive Medication Adherence

Poor adherence to antihypertensive medications is associated with morbidity, and data
suggest that substance abuse may contribute to poor adherence. Contingency management (CM),
an intervention highly efficacious for improving outcomes of substance abusers, shows
promise in improving medication adherence in a handful of small trials. CM involves
providing tangible reinforcement each time the behavior (medication ingestion) is exhibited.
Thus far, studies evaluating CM for increasing medication adherence have utilized MEMS caps,
but reinforcement of adherence via MEMS caps is done relatively infrequently and with delay,
hindering its efficacy. A widely utilized technology that may be more appropriate for
reinforcing medication adherence is cell phones, which can record the process of pill
ingestion through video functions. As regular monitoring and feedback is important in the
efficacy of CM, patients can be provided with daily messages regarding adherence and CM
earnings. In this pilot study, we propose to randomize 40 hypertensive substance abusing
patients with suboptimal adherence to antihypertensive medications to one of two 12-week
treatment conditions: (1) usual care, or (2) usual care with cell phone monitoring and CM.
In the CM condition, patients will carry a cell phone and record and send in time- and
date-stamped self videos of medication ingestion. These patients will receive congratulatory
messages or reminders about adherence, and they will earn vouchers each time medication
ingestion occurs at the appropriate time, along with bonuses for sustained adherence. We
hypothesize that the CM condition will improve self report and pill count measurements of
medication adherence and that it will result in decreased blood pressure. Results from this
study may have widespread implications for the use of cell phones as a novel technology to
improve medication adherence.