Background: Clinical experience suggests that lung cancer (LC) is associated with sleep disturbances that may contribute to impaired daytime functioning and quality of life. Using questionnaires and home actigraphic recordings, we tried to determine whether sleep quality and daytime alertness are impaired in patients with newly diagnosed LC.
Patients and methods: Twenty-nine outpatients with newly diagnosed LC and an Eastern Cooperative Oncology Group performance status </=2 and 14 age- and sex-matched non-cancer (NC) patients with successfully treated sleep apnea were enrolled in the study. Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI) and by night actigraphic data. Daytime alertness was assessed by the Epworth Sleepiness Scale (ESS) and day actigraphic data. The medical outcomes study 36-item short form (SF-36) was used for quality of life assessment.
Results: LC patients had higher PSQI (9.6+/-3.7 versus 5.6+/-3.2; p<0.001) and higher ESS (8.6+/-3.7 versus 5.6+/-3.2; p=0.01) than NC patients indicating worse quality of sleep and more excessive daytime sleepiness. Both physical and mental components score of SF-36 were lower in LC patients (p<0.001) indicating lower quality of life. Wrist actigraphy data showed significantly lower sleep efficiency and a higher sleep fragmentation during the night and lower mean activity during the day in LC patients.
Conclusions: Patients with newly diagnosed LC and performance status </=2 present marked sleep disturbances, excessive daytime sleepiness and impaired quality of life. Further studies are required to determine the etiologic factors of sleep disturbances in LC patients and the impact of pharmacologic and non-pharmacologic interventions on sleep and daytime functioning.