This three group randomized controlled trial evaluated the effect of a Decision Aid (DA) with and without an additional Decisional Counseling Program (DCP) for patients being examined for coronary artery disease (CAD) on patient-reported health outcomes and health related quality of life (HRQoL), mediated by adherence to cardiac risk reduction behavior. We also explored how adherence to cardiac risk reduction behavior was influenced by patients’ intentions to follow recommendations for a healthy lifestyle, their knowledge about risk factors for CAD, perceived health beliefs, perceived benefits and barriers to cardiac risk reduction behavior, and decisional conflict. Furthermore, we explored relationships between adherence to cardiac risk reduction behavior, health outcomes and HRQoL.
368 patients > 18 of age were randomly assigned to: (1) the Intervention group I where patients received, for take home, the DA prior to their scheduled angiogram; (2) the Intervention group II where patients, in addition to the DA received the DCP from a trained nurse counselor in their homes prior to their angiogram; and (3) the Control group who received “usual care”. Data were collected at four time points: at baseline prior to patients’ angiogram, and at 2, 4, and 6 months. ANCOVA was used to compare differences in group means at 6 months following the angiogram after statistically controlling for baseline scores. Linear regression and mixed effects models were used to explore relationships between primary outcomes and mediating variables.
While there were no significant differences between the Da group and the Control group on any variables, The DA+DCP group had a significant decrease in Body Mass Index compared to the Control group 6 months after the intervention. Furthermore, patients in the DA+DCP group significantly improved HRQoL on several dimensions over the study period compared to the Control group. There was also a significant decrease in perceived barriers to cardiac risk reduction behavior in the DA+DCP group compared to the Control group. We found no significant group differences in adherence to cardiac risk reduction behavior. Greater adherence to healthy life style recommendations, better HRQoL and better health outcomes were significantly related. Intentions to follow lifestyle recommendations were significant predictors of adherence to cardiac risk reduction behavior. Increased perceived susceptibility of illness was significantly related to lower adherence to non- smoking behavior, while increased perceived barriers to cardiac risk reduction behavior was related to lower adherence to diet recommendations. Higher decisional conflict significantly predicted lower adherence to diet recommendations, activity recommendations, and taking medications. The patients appraised both the DA and the additional decisional counseling program as helpful.
In this study the DA alone was not sufficient to improve health behaviors and outcomes. However, the addition of the DCP had significant effects on reduced BMI, better HRQoL on several dimensions, and reduced perceived barriers to cardiac risk reduction behavior in patients being examined for CAD. The DCP supported patients to individually tailor their lifestyle changes to their health beliefs and preferences, resulting in better health outcomes and HRQoL. We do not know however, if these effects would have occurred by the DCP alone, without combining it with the DA. Finally, this study contributed to a better understanding of variables related to adherence to lifestyle recommendations and health outcomes.