Introduction – Sleep problems are commonly reported by cancer survivors, however, knowledge of the impact of chemotherapy-induced peripheral neuropathy (CIPN) on sleep quality remains limited. In this study, we investigated the prevalence of poor sleep-quality in neurotoxic chemotherapy-treated patients and explored the impact of CIPN of sleep-quality, as well as identifying clinical characteristics associated with poor sleep-quality.
Methods – Participants were assessed cross-sectionally post-neurotoxic chemotherapy (predominantly taxane, platinum-based or bortezomib). CIPN severity was graded using a patient-reported outcome (EORTC-QLQ-CIPN20), a health-related quality-of-life outcome measure (CAP-PRI), a clinically-graded scale (NCI-CTCAE) and a neurological examination score (Total Neuropathy Score-clinical version(TNSc)). Nerve-conduction studies of sural and tibial nerves were completed. Sleep quality was assessed using a self-rated questionnaire (Pittsburgh Sleep-Quality Index, PSQI), with a cut-off of ≥5 out of 21 identifying participants with poor sleep quality. Responses of “Not at all” or “A little bit/ A lot” to the question “do you have trouble sleeping due to neuropathy?” were used to further classify participants with poor sleep quality. Group comparisons were investigated using Mann-Whitney U tests or independent sample t-tests.
Results – 77 participants (mean age=63.4±11.3) who were reporting CIPN (NCI-CTCAE grade≥1) were included. Fifty-eight participants (75%) reported poor sleep-quality. Of these 58 participants, 24 (41%) reported CIPN as cause of trouble sleeping, while 34 (59%) reported other causes. Overall, there were no group differences in age or BMI (all p>0.05). However, participants with CIPN-induced sleep impairment had higher CIPN severity on the patient-reported outcome (EORTC-QLQ-CIPN20, p<0.001;), clinically-graded scale (p=0.001) and neurological examination score (p=0.01), as well as more reported neuropathic pain (PNRS, p=0.007) compared to those with sleep impairments due to other causes. Furthermore, participants with CIPN-induced sleep impairments reported worse impact of neuropathy on physical and social functioning, as well as worse emotional well-being (all p<0.05) on the health-related quality-of-life outcome measure (CAP-PRI).
Conclusions – Participants with CIPN-induced poor sleep quality reported higher scores across all CIPN severity measures. This emphasises the negative impacts of CIPN symptoms on quality of life of chemotherapy-treated patients and highlights the importance of sleep quality assessment in hopes of informing better treatment options for cancer survivors.