Psychological adjustment and quality of life with late -stage cancer patients: Empirical evaluation and critique of cognitive adaptation theory.

摘要

Facilitating quality of life as people adjust to end-of-life has been considered one of the hallmarks of palliative care (NHPCO, n.d.). Although the dominant model used by clinicians to facilitate quality of life at end-of-life (e.g., Kubler-Ross' 1969 stage model) suggests that acceptance is the ideal state of adjustment, other researchers have found (e.g., Reed et al., 1994) realistic acceptance to predict poorer quality of life in terminally ill patients. Research in this area has been scant. Additionally, Kubler-Ross' stage model lacked empirical scrutiny and did not adequately predict adjustment to end-of-life. An adjustment to illness model, the Cognitive Adaptation Theory (CAT; Taylor, 1983), suggests that people adjust to illness using slightly illusionary, positive attributions of self, control, and meaning. However, Cognitive Adaptation has not been tested with a terminally ill population and has been poorly operationalized in extant literature, measuring optimism instead of meaning. This study explored the Cognitive Adaptation Theory, including meaning (LRI; Battista & Almond, 1973), control (CBI; Sirois, 2007), and self-esteem (Rosenberg Self-Esteem Scale; Rosenberg, 1965), as well as the role of optimism (LOT-R; Scheier et al., 1994), in a population of 80 culturally diverse late-stage cancer patients using a correlational cross-sectional design. Multiple regression analyses tested whether Cognitive Adaptation indices predicted psychological and physical quality of life (SF-36; Ware et al., 1993) at end-of-life and whether this effect was moderated or mediated (Baron & Kenny, 1986) by optimism. Results suggested that Cognitive Adaptation Theory (Taylor, 1983) applied to late-stage cancer patients. Greater levels of self-esteem, control, and meaning predicted physical and psychological quality of life. Physical quality of life was most influenced by control beliefs, while psychological quality of life was most influenced by self-esteem. Optimism independently predicted physical quality of life and neither mediated nor moderated the relationship between Cognitive Adaptation and quality of life. This study demonstrated that slightly positive, illusionary beliefs of self, control, and meaning predicted quality of life even in the presence of clear, disconfirmatory environmental evidence. Results call into question broad application of Kubler-Ross' (1969) stage model in facilitating quality of life in dying cancer patients.