Illness intrusiveness and subjective well-being in patients with glioblastoma

Glioblastoma (GBM) is the most common adult CNS malignancy but its impact on quality of life (QOL) is poorly understood. In other patient populations, illness intrusiveness (the extent to which disease and treatment disrupts valued activities and interests) is associated with low subjective well-being, after controlling for disease and treatment variables. In this cross-sectional cohort study, we examined the relations among illness intrusiveness, disease burden, and subjective well-being in GBM. 73 GBM patients completed validated self-report measures of depression, positive affect, illness intrusiveness, and health-related QOL. Responses were compared to data from six other cancer groups using repeated measures analyses of variance. Hierarchical multiple-regression analyses tested the hypothesis that illness intrusiveness accounts for well-being after controlling for the effects of disease burden. GBM patients reported less positive affect, more depression, and more illness intrusiveness than people with other cancers. Illness intrusiveness correlated with depression and (low) positive affect. Associations among cancer symptoms, depression, and positive affect decreased when illness intrusiveness was added to regression equations. Good performance status and high cancer-symptom burden were associated with illness intrusiveness and depression. GBM patients report greater distress, lower positive affect, and more illness intrusiveness than people with other cancers. Subjective well-being is mediated in part by illness intrusiveness in this population. In addition to medical treatment, efforts to help patients remain engaged in valued activities and interests may help preserve QOL after the diagnosis of a GBM.