Subjective sleep quality in lung cancer patients before and after chemotherapy

Sleep disturbances, such as difficulty in falling asleep, maintaining sleep, poor sleep efficiency, early awakening, and excessive daytime sleepiness, are common in patients with cancer. The aim of this study was to evaluate sleep characteristics in newly diagnosed lung cancer patients before and after three months of chemotherapy treatment.

Forty-nine patients with lung cancer, without brain metastasis, were included. Anthropometric and disease characteristics were collected. Upon diagnosis and after three months, a polysomnographic examination was conducted and the patients completed the Epworth Sleepiness Scale (ESS), the Pittsburgh Sleep Quality Index (PSQI), the Fatigue Severity Scale (FSS) and the Medical Research Council (MRC) dyspnoea scale.

Before chemotherapy, the mean PSQI score was 7.1 ± 4, the FSS score was 3.92 ± 2, and the ESS score was 6.8 ± 4. The MRC score was low at 1.6 ± 1.1. A significant correlation between FSS and global PSQI was revealed (r = 0.424, P < 0.01), as well as with several of the PSQI components. After chemotherapy, no statistically significant change was observed in the PSQI (mean: 6.6 ± 4.5, t-score: 0.784, P = 0.438), or the FSS score (4.4 ± 2.2, t-score: -1.375, P = 0.177). Sleep efficiency was significantly reduced (P = 0.008), without any change in the distribution of sleep stages.

The perception of sleep quality is poor among newly diagnosed lung cancer patients and is correlated with fatigue. After chemotherapy, self-reported sleep impairment is present and sleep efficiency is reduced, without significant change in sleep architecture.