Last term, my Program Planning for Health Behavior Change workgroup was charged with using theory to help explain a health behavior and design a targeted intervention. With several MDs in my group, we chose improving warfarin adherence to reduce risk of stroke in elderly patients with atrial fibrillation.
2.2 million Americans suffer from AF, a condition that causes a 4 to 5 fold increased risk for stroke. What is worse is that 5% of those ages 65+ have AF. Luckily, warfarin is an inexpensive, generic drug that, if taken consistently and with regular physician monitoring, can reduce the risk of stroke for AF patients. However, compliance is a problem and as a result non-compliant AF patients remain at risk for stroke.
My group utilized a PRECEDE/PROCEED framework to conduct a hypothetical needs assessment and identify the underlying causes of the problem that our resulting intervention would address. This framework provides a conceptual way of organizing multiple levels of factors that explain prescription regimen noncompliance and identify places where an intervention may be effective. Utilizing our course textbook, Health Behavior and Health Education: Theory, Research, and Practice by Glanz, Rimer, and Viswanath, we found that examining the following factors was particularly important in explaining whether one is adherent:
- Predisposing factors – the motivation or rationale for behavior and include one’s attitudes, beliefs, preferences, skills
- Reinforcing factors – the reward or incentive for persistent behavior such as social support, modeling, peer influence
- Enabling factors – direct or indirect antecedents that allow motivation to be realized, including environmental and structural factors
We also used social cognitive theory, which focuses on the individual as a health behavior change agent, and its theoretical constructs. In reviewing the literature, we found that elderly AF patients may:
- lack the self-regulation to remember to take their medication consistently or to organize taking this particular medication among others that need to be taken throughout the day
- have a weak self-efficacy belief and feel incapable of adhering to their prescription regimen
- lack incentive motivation and not see the link between adherence and good outcome expectations; if they take warfarin once or several times, they may not see an instant reward, feel different, or see that they have reduced their risk of stroke
- have facilitation difficulty in physically getting to their provider’s office for the required physician monitoring
In summary, we found that adherence is an individual behavioral issue with layers of causal factors (identifiable via social cognitive theory) and surrounded and impacted by environmental factors, which can be organized using the PRECEDE/PROCEED framework. Although we designed a hypothetical intervention that addressed the predisposing, reinforcing, and enabling factors specific to warfarin compliance, these tools could also be used to examine adherence issues for other drugs.
