Individual and Joint Associations of Depression-Related Symptoms and Sleep Quality With Overall Survival Among Patients With Ovarian Cancer: Evidence From a Prospective Cohort Study

Abstract

Background: As the evidence linking depression and sleep quality to overall survival (OS) is lacking, we aim to evaluate the individual and joint associations of depression-related symptoms and sleep quality with OS among patients with ovarian cancer (OC).

Method: A total of 554 patients with OC were included. Depression-related symptoms and sleep quality were measured using the Patient Health Questionnaire (PHQ-9) and the Pittsburgh Sleep Quality Index (PSQI). The primary analysis utilized the average levels of depression-related symptoms and sleep quality by averages of PSQI score and PHQ score between pre-diagnosis and post-diagnosis. Deaths were ascertained until February 16, 2023, via medical records and active follow-up. Cox proportional hazard regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of the joint and individual associations of sleep quality and depression-related symptoms with OC survival.

Result: A total of 205 deaths occurred during a median follow-up of 44.6 months. The average level of depression-related symptoms and sleep quality were independently associated with OS (HR_{depression vs. no depression} = 1.55, 95% CI = 1.10–2.17; HR_{poor sleep vs. good sleep} = 2.05, 95% CI = 1.51–2.75). We documented multiplicative and additive interactions between these two factors in relation to OS (P_interaction < 0.01; relative excess risk due to interaction = 0.16, 95% CI = 0.01–0.31). Combinations of depression-related symptoms and poor sleep quality were positively associated with OC mortality (HR = 2.61, 95% CI = 1.70–4.00), compared to patients with good sleep quality and without depression-related symptoms.

Conclusion: Poor OC survival was observed among patients with poor sleep quality and depression-related symptoms, independently and jointly.