Identifying illness perception schemata and their association with depression and quality of life in cardiac patients.

The purpose of this paper is to identify groups of cardiac patients who share similar perceptions about their illness and to examine the relationships between these schemata and psychosocial outcomes such as quality of life and depression. A total of 190 cardiac patients with diagnoses of myocardial infarction, stable angina pectoris or chronic heart failure, completed a battery of psychosocial questionnaires within four weeks of their admission to hospital. These included the Brief Illness Perceptions Questionnaire (BIPQ), Beck Depression Inventory II (BDI II) and The MacNew Health-related Quality of Life instrument (MacNew). BIPQ items were subjected to latent class analysis (LCA) and the resulting groups were compared according to their BDI II and MacNew scores. LCA identified a five-class model of illness perception which comprised the following: (1) Consequence focused and mild emotional impact, n = 55, 29%; (2) Low illness perceptions and low emotional impact, n = 45, 24%; (3) Control focused and mild emotional impact, n = 10, 5%; (4) Consequence focused and high emotional impact, n = 60, 32%; and (5) Consequence focused and severe emotional impact, n = 20, 10%. Gender and diagnosis did not appear to reflect class membership except that class 2 had a significantly higher proportion of AMI patients than did class 5. There were numerous significant differences between classes in regards to depression and health-related quality of life. Notably, classes 4 and 5 are distinguished by relatively high BDI II scores and low MacNew scores. Identifying classes of cardiac patients based on their illness perception schemata, in hospital or shortly afterwards, may identify those at risk of developing depressive symptoms and poor quality of life.