Effect of cancer treatment on sleep quality in cancer patients: A systematic review and meta-analysis of Pittsburgh Sleep Quality Index

Sleep problems are one of the most common symptoms experienced by cancer patients. The causes of poor sleep quality might be due to treatment and its side effects. Thus, we conducted this systematic review and meta-analysis with the aims of investigating sleep quality during treatment in cancer patients.Comprehensive search strategy was conducted in the following original databases: PubMed, Web of Science (ISI), Scopus, Embase, PsycINFO, and Ovid, from 1950 to 15th February 2021. Studies that investigated the sleep quality during treatment in cancer patients were included. Two investigators extracted all relevant data, independently. For deriving mean difference, random-effects meta-analyses were used. We assessed quality of studies by Newcastle-Ottawa Scale (NOS).A total of 27 studies (1884 participants) were included in the syntheses on sleep quality. The mean global Pittsburgh Sleep Quality Index (PSQI) in cancer patients before the initiation of treatment was 7.11 (95% CI: 6.48, 7.74), during 8.31 (95% CI: 6.34, 10.27), after the treatment 7.10 (95% CI: 6.54, 7.66), and finally, the mean global PSQI in the time of follow-up was estimated 7.33 (95% CI: 6.27, 8.39); all the results were meaningful (P < 0.001). The mean difference showing the quality of sleep was better before the initiation of treatment compared to after the treatment.Cancer patients who underwent cancer treatment face lots of problems and adverse effects caused by treatment. Our results revealed that cancer patients experience poor quality of sleep during the whole trajectory of cancer even after a year from the initiation of treatment. After the end of treatment, sleep quality got better compared to during the treatment and returned to before the treatment level, but it is still poor and needs more sleep-related interventions to improve.