Diurnal cortisol, perceived sleep quality, actigraphic sleep and depression: an exploratory pilot in patients with head and neck cancer

Background In patients with head and neck cancer (HNC), perceived sleep quality, actigraphy-derived sleep parameters, depressive symptoms, and diurnal cortisol may represent related behavioral and biological processes. This exploratory study tested a priori associations among these constructs. Methods Forty patients with HNC completed the Pittsburgh Sleep Quality Index (PSQI) and Patient Health Questionnaire-9 (PHQ-9), wore wrist actigraphs, and collected salivary cortisol at waking and bedtime across a 6-day period. Separate linear regressions tested associations of PSQI scores with actigraphic sleep measures with depressive symptoms, and with cortisol slope, waking, evening and mean indices. Post hoc PSQI item analyses used Spearman correlations. Results Global PSQI scores were not significantly correlated with actigraphic sleep parameters. Poorer perceived sleep quality was associated with higher depression scores (r = 0.64), flatter diurnal cortisol slopes (r = 0.48), and higher evening cortisol (r = 0.40). Actigraphic sleep parameters were not significantly associated with depressive symptoms or cortisol indices, and depressive symptoms were not significantly associated with cortisol indices. Post hoc item-level analyses showed that poorer overall sleep quality and greater difficulty maintaining enthusiasm were associated with greater depressive symptoms, flatter cortisol slopes, and lower waking cortisol. Conclusion In this exploratory pilot of patients with HNC, poorer sleep quality was associated with greater depressive symptoms, flatter diurnal cortisol slopes, and higher evening cortisol, whereas actigraphic sleep parameters were not. Global PSQI scores may help identify patients warranting further assessment for depression and treatment-related symptoms.