This study aimed to examine the effect of motivational interviewing on healthy lifestyle behaviors and biochemical parameters in patients who underwent stent implantation after coronary angiography. Specifically, it investigated whether a structured motivational interviewing program could improve patients' health-promoting behaviors and positively influence biochemical outcomes such as blood lipid levels and body mass index (BMI). The research was designed as a randomized controlled study and was conducted in the cardiology outpatient clinic of a training and research hospital in Istanbul. The study included patients diagnosed with coronary artery disease who had undergone coronary angiography followed by stent implantation and were being followed in the outpatient clinic. Participants were randomly assigned to either the intervention group or the control group. In the intervention group, patients received a motivational interviewing-based program over a three-month period. This program included face-to-face educational sessions lasting approximately 30-45 minutes, focusing on coronary artery disease, risk factors, healthy nutrition, physical activity, stress management, sleep regulation, and smoking cessation. In addition, participants received reminder messages twice a week to support behavioral change and encourage adherence to healthy lifestyle practices. The control group continued their routine medical follow-up and standard care without additional intervention. Data were collected at baseline and at the end of the third month. In the intervention group, data were additionally collected at the end of the first month. Both groups were evaluated using the Health-Promoting Lifestyle Profile II scale, and biochemical parameters including HDL, LDL, total cholesterol, triglycerides, and BMI were measured and recorded. The study aimed to determine whether motivational interviewing could serve as an effective nursing intervention to promote sustainable lifestyle changes and improve clinical outcomes in patients with coronary artery disease following stent implantation.

Coronary artery disease is characterized by the development of atherosclerotic plaques in the epicardial coronary arteries, leading to progressive narrowing of the vessel lumen and reduced myocardial perfusion. Atherosclerosis is a chronic inflammatory process influenced by modifiable and non-modifiable risk factors. Modifiable risk factors include hypertension, diabetes mellitus, dyslipidemia, smoking, physical inactivity, and unhealthy dietary habits, while non-modifiable factors include age, sex, and genetic predisposition. Coronary artery disease is one of the leading causes of morbidity and mortality worldwide and is associated with major cardiovascular events such as myocardial infarction and stroke.

Lifestyle modification is a fundamental component of both primary and secondary prevention of coronary artery disease. However, a considerable proportion of patients continue unhealthy behaviors following coronary interventions, increasing the risk of recurrent cardiovascular events. For this reason, interventions aimed at promoting sustainable behavioral change are essential in this population. Health-promoting behaviors, including regular physical activity, balanced nutrition, stress management, medication adherence, and smoking cessation, are critical in reducing cardiovascular risk and improving clinical outcomes. Motivational interviewing is a patient-centered counseling approach designed to enhance intrinsic motivation for behavioral change. It is particularly effective in individuals who are ambivalent or resistant to change and is based on principles such as expressing empathy, developing discrepancy between current behaviors and health goals, rolling with resistance, and supporting self-efficacy. This approach is widely used in chronic disease management and nursing practice to support behavioral change.

In this study, a structured motivational interviewing-based intervention supported by educational sessions and reminder messages was developed to improve healthy lifestyle behaviors in patients with coronary artery disease who underwent coronary angiography and stent implantation and were followed in a cardiology outpatient clinic. The intervention was also designed to improve biochemical parameters, including lipid profile indicators and body mass index. This randomized controlled trial was conducted in the cardiology outpatient clinic of a tertiary training and research hospital in Istanbul, Türkiye. The study population consisted of adult patients with coronary artery disease who underwent stent implantation following coronary angiography and were under outpatient follow-up. The sample size was determined using a power analysis. Participants were allocated to the intervention and control groups using simple randomization. Inclusion criteria included age 18 years or older, ability to read and understand Turkish, at least one month post-stent implantation or balloon angioplasty, clinical stability, and access to a mobile phone. Patients with psychiatric disorders affecting participation, communication difficulties, or severe clinical instability were excluded.

The intervention group received a structured face-to-face educational session covering coronary artery disease, risk factors, nutrition, physical activity, stress management, sleep hygiene, and smoking cessation, followed by motivational interviewing sessions and twice-weekly reminder messages for three months. The control group received routine clinical follow-up without additional intervention. Health-promoting lifestyle behaviors were assessed using the Health-Promoting Lifestyle Profile II scale. Biochemical outcomes, including lipid profile parameters (HDL, LDL, total cholesterol, triglycerides) and body mass index, were used to evaluate clinical outcomes. Assessments were performed at baseline, at one month, and at three months. Body mass index was calculated as weight in kilograms divided by height in meters squared. Data were collected using standardized instruments and analyzed using appropriate statistical methods. Statistical significance was set at p < 0.05. Ethical approval was obtained from the relevant institutional ethics committee, and written informed consent was obtained from all participants before enrollment.

Inclusion Criteria:

• Patients aged over 18 years,
• Able to understand Turkish and literate,
• Patients who had undergone stent placement after coronary angiography (at least 1 month after stent implantation or balloon angioplasty),
• Patients whose health status was appropriate for participation in the study,
• Patients who owned a mobile phone.

Exclusion Criteria:

• Patients with a diagnosed psychiatric disorder,
• Patients with whom communication could not be established,
• Patients with poor general health status.