Intervention Designed to Increase Adherence and Improve BP

Much of the racial gap in mortality rates between whites and African Americans can be attributed to the disproportionate number of African Americans with poorly controlled hypertension. Lack of adherence to medication regimens may explain the poor blood pressure (BP) control among African Americans. The adverse effect of inadequate adherence on cardiovascular mortality and morbidity has been well established, creating a need for interventions designed to improve adherence and narrow the racial gap in outcomes related to hypertension.

The most common feature of successful adherence improvement interventions is a multifaceted strategy such as the behavioral-education combination. However, according to researchers, the effectiveness in primary care of interventions that are based on the social cognitive theory of human behavior with an emphasis on self-efficacy have not been sufficiently tested, particularly among minority patients.

The researchers recently conducted a study among African Americans with hypertension in a primary care practice to determine whether a patient education (PE) intervention combined with positive-affect induction and self-affirmation (PA) was more effective than PE alone in improving adherence to medications and reduction in BP. They reported results of the study in Archives of Internal Medicine [2012;172(4):322-326].

The 2-arm, randomized controlled study included 256 hypertensive African Americans in 2 primary care practices. Following enrollment and baseline assessment, participants were followed up via bimonthly telephone interviews for 12 months. The primary outcome measures were medication adherence and within-patient change in BP from baseline to 12 months.

At baseline, research assistants (RAs) assessed patient eligibility and demographic status, and reviewed each patient’s electronic medical record for office BP readings, medication list, and comorbidity using the Charlson Comorbidity Index. Patients were provided with validated self-report measures to assess depressive symptoms, social support, medication adherence, and positive and negative affect. Each patient was given an electronic pill monitor used to measure adherence to prescribed antihypertensive medication.

Patients where then randomized in a 1:1 ratio to either the PE control group or the PA intervention group. Patients in the PE control group received a culturally tailored educational workbook designed to enhance patients’ knowledge about hypertension, improve self-management behaviors, and support goal setting. The RAs met with the patients to review the workbook and followed the meeting with bimonthly telephone calls to assess the patient’s behavioral contract and confidence to adhere to the medication regimen. The assessments were used to identify and advise the patient on possible barriers to adherence.

Patients in the PA intervention group received the same workbook, enhanced with a chapter addressing the benefits of “positive moments in overcoming obstacles to medication adherence.” They also received 2 forms of PA during the bimonthly follow-up telephone calls: (1) after noting things in their lives that made them feel good, they were asked to incorporate those positive feelings into their daily lives; and (2) unexpected small gifts were sent to them in the mail prior to each telephone follow-up.

At baseline, the groups had similar BP (mean BP 137/82 mm Hg), 36% of patients had diabetes, 11% had stroke, and 3% had chronic kidney disease. At 12 months, based on the intention-to-treat principle, medication adherence in the PA group was 42% compared with 36% in the PE group (P=.049). The within-group reduction in systolic BP and diastolic BP for the groups was not significant.