The Relationship between Illness Perception, Mentalization and Personality Type D with the Quality of Life of Coronary Heart Disease Patients: An Application of Structural Equation Model

Patients who suffered coronary artery disease (CAD) experience a lower quality of life.This study aimed to investigate the mediating role of the illness perception variable in the relationship between mentalization and personality type D with quality of life in patients with coronary heart disease.

The present study was performed using correlation modeling using structural equation modeling. Based on Cohen's sample size determination table, 210 patients with coronary heart disease were enrolled by random sampling method. Questionnaires of personality type D, quality of life (SF-36), mentalization (Ment S) and disease perception (IPQ) were used to gather data for this study which were completed by the patients themselves. After data collection, the relationship between the two variables with Pearson correlation and the interactive relationship in the structure of the theoretical model drawn in this study was evaluated using structural equation modeling.

The final research model had a very good fit. The results showed a direct effect of D personality type and disease perception on quality of life but the direct effect of mentalization on quality of life was not significant. Also, the indirect effect of personality type D and mentalization through disease perception on quality of life was statistically significant.

Cognitive and emotional representation of the disease, which is the illness perception, can mediate the relationship between psychological and personality variables with quality of life. Therefore, in improving the perception of the disease to improve the quality of life of patients, personality, behavioral and psychological variables can serve as targets of intervention.