Sleep and quality of life in long-term lung cancer survivors.

BACKGROUND Sleep problems are common in lung cancer survivors, yet little is known about the prevalence, determinants, and effects on quality of life (QoL) of these sleep problems in long-term lung cancer survivors. METHODS A case-control study design comparing 76 elderly lung cancer survivors (LCS, >5 years post diagnosis with mean survival time of 8 years+/-2.1 years) and 78 elderly non-cancer controls (NCC). Measurements included a standardized questionnaire for sleep (Pittsburgh Sleep Quality Index-PSQI), and analogue scales for dyspnea, pain, and other comorbid symptoms, as well as demographic factors and cancer history. RESULTS Overall, 56.6% of LCS had poor sleep (PSQI global score >5) as compared to only 29.5% of NCC (p<0.001), and 49.2% of LCS who did not have sleep difficulties prior to their lung cancer diagnosis ultimately developed them. There was also evidence of significant impairments in sleep efficiency in LCS (78.3%) relative to NCC (89.6%, p<0.001), predominantly due to increased nocturnal awakenings. A single-item analogue scale for sleep quality was not as effective in identifying sleep problems as more specific questions about sleep duration and sleep efficiency. Poor sleep quality was significantly correlated with impairments in quality of life, even when controlling for other factors, such as dyspnea. CONCLUSIONS Even 8 years after diagnosis, LCS continue to have significant sleep difficulties. By asking specific questions about sleep medication use, nocturnal awakenings and sleep efficiency, health care providers can identify sleep problems that could be treated and potentially improve the quality of life of their patients.