Abstract
METHODS
Several cohorts from the population-based PROFILES registry, including adult cancer survivors diagnosed between 1990 and 2014 with 11 cancer diagnoses, were used. Data on sleep quality (3 categories: no, non-clinically, and clinically important sleep quality impairment) was collected through the insomnia scale of the EORTC QLQ-C30 and the PSQI for CRC survivors only (n = 1245). Clinical data were obtained through the Netherlands Cancer Registry. Cox regression analysis was used to assess adjusted hazard ratios (HRs).
CONCLUSION
Cancer patients reporting clinically low sleep quality had a lower OS. However, this might be partly explained by patients' depressive symptoms. In CRC survivors, daytime dysfunction and long sleep duration were, independent of depressive symptoms, related to lower OS.
RESULTS
7195 participants were included, of which 36 % died (median follow-up since inclusion, 9 years). Clinically impaired sleep quality was associated with lower OS (HR, 1.17[1.05; 1.30]) compared to no sleep problems. Stratification by cancer diagnosis suggested a consistent pattern. After adjusting for depressive symptoms, sleep quality was no longer significantly associated with OS (HR, 1.10[0.97; 1.24]). Daytime dysfunction and long sleep duration were significantly associated with lower OS in CRC survivors, also after adjustment for depressive symptoms.
BACKGROUND
This study aimed to determine whether: 1) sleep quality was associated with overall survival (OS) among a heterogeneous sample of cancer survivors; 2) this association differed per cancer diagnosis; 3) aspects of sleep quality (e.g., sleep latency, daytime dysfunction) were associated with OS among a subsample of colorectal cancer (CRC) survivors; and 4) adjustment for depressive symptoms changed these associations.