Motivational Interviewing

• Score on Morisky Medication Adherence Scale (MMAS-4) [ Time Frame: Up to one year from baseline ] [ Designated as safety issue: No ]
  Adherence to antihypertensive medications will be assessed at baseline and every three months thereafter for one year using a validated 4-item scale developed by Morisky that specifically addresses medication-taking. The scale asks patients to respond "yes" or "no" to a set of 4 questions. A positive response to any question indicates a problem with adherence. Each positive answer is assigned a score of 1. The total possible score is 4 with higher score indicating poorer adherence.
  
  

• Blood pressure readings [ Time Frame: Up to one year from baseline ] [ Designated as safety issue: No ]
  Within clinic systolic and diastolic blood pressure readings will be assessed at baseline and at every three months thereafter for one year using a mercury syphgmomanometer.
  
  
• Score on efficacy scale [ Time Frame: Up to one year from baseline ] [ Designated as safety issue: No ]
  Self-efficacy will be assessed at baseline and every three months thereafter for one year using a 44-item self-efficacy scale devised based on Bandura's Scale. Patients are asked to rate their confidence in taking their blood pressure medications under a variety of situations that may pose difficulties to them using a 3-point likert response format - 1= not at all sure, 2= somewhat sure, and 3= very sure. A summary score is computed by summing the responses, with higher scores reflecting high self-efficacy.
  
  
• Score on the Treatment Self-Regulation Questionnaire (TSRQ) [ Time Frame: Up to one year from baseline ] [ Designated as safety issue: No ]
  Intrinsic motivation will be assessed at baseline and every three months thereafter for one year with aid of TSRQ. It is used to assess the degree to which one's motivation for a particular behavior is relatively autonomous or self-determined. Patients are provided with 15 reasons why they may not take their medications as prescribed and asked to indicate the degree to which each reason is true on a scale of 1 to 7 with 7 been very true.
  
  

The objective of this randomized control trial is to evaluate, among 190 African-American patients with poorly controlled hypertension followed in a community-based primary care practice, whether motivational interviewing is more effective than usual care (routine counseling) in achieving adherence to prescribed blood pressure medications at 12 months.

The project aims to: 1) determine whether patients who receive motivational interview counseling have greater reduction in both systolic and diastolic blood pressure than those in the control group at 12 months. Clinic blood pressure readings will be assessed at baseline and at every three months thereafter for one year and 2) assess the effect of self-efficacy and intrinsic motivation as potential mediators of motivational interview on adherence. Self-efficacy and intrinsic motivation will be assessed at baseline and every three months thereafter for one year.