Abstract
BACKGROUND: Multiple alterations in circadian rhythms have been observed in cancer patients, including the diurnal rhythm of the adrenal hormone cortisol. Diurnal cortisol alterations have been associated with cancer-related physiological processes as well as psychological stress. Here we investigate alterations in diurnal cortisol rhythm in ovarian cancer patients, and potential links with depression, life stress, and functional disability. METHODS: Women (n = 177) with suspected ovarian cancer completed questionnaires and collected salivary cortisol 3× daily for 3 consecutive days before surgery. One hundred women were subsequently diagnosed with ovarian cancer and 77 with benign disease. In addition, healthy women (n = 33) not scheduled for surgery collected salivary cortisol at the same time points. RESULTS: Ovarian cancer patients demonstrated significantly elevated nocturnal cortisol (P = .022) and diminished cortisol variability (P = .023) compared with women with benign disease and with healthy women (all P values <.0001). Among ovarian cancer patients, higher levels of nocturnal cortisol and less cortisol variability were significantly associated with greater functional disability, fatigue, and vegetative depression, but not with stress, distress, or depressed affect. There were no significant associations between functional or psychological variables and diurnal cortisol in women with benign disease. CONCLUSIONS: Nocturnal cortisol and cortisol variability show significant dysregulation in ovarian cancer patients, and this dysregulation was associated with greater functional disability, fatigue, and vegetative depression. These findings suggest potential hypothalamic-pituitary-adrenal involvement in functional disability in ovarian cancer, and may have implications for disease progression.