Factors Associated with Poor Sleep Quality in Cancer Patients Undergoing Chemotherapy: A Cross-sectional Study in Vietnam

Abstract

Background: Cancer patients undergoing chemotherapy often experience multiple treatment - related adverse effects. Although chemotherapy improves survival outcomes, it is frequently accompanied by side effects that substantially impair quality of life. Sleep disturbances are among the most common problems, yet they remain underrecognized in routine clinical practice. Poor sleep quality may worsen fatigue, reduce treatment adherence, and negatively affect overall well - being. In Vietnam, evidence on sleep quality among cancer patients receiving chemotherapy remains limited. Objectives: The objective of this study is to identify factors associated with poor sleep quality among cancer patients undergoing chemotherapy in Vietnam. Methods: A cross - sectional study was conducted among 432 cancer patients receiving chemotherapy using convenience sampling. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), which includes 19 items across 7 components and evaluates sleep quality over the previous month; a global PSQI score of > 5 indicated poor sleep quality. Data were analyzed using the Chi - square test or Fisher’s exact test, followed by multivariable Poisson regression with robust variance estimation to identify factors associated with poor sleep quality. Results: A total of 432 cancer patients were included, with a median age of 59 years (IQR: 47.5 - 66; range: 18 - 85 years). Females accounted for 55.3% of the study population. The median PSQI score was 5.0 (IQR: 4.0 - 8.5), and 49.8% of patients were classified as having poor sleep quality. In the adjusted model, poor sleep quality was associated with other comorbidities, cancer stage III - IV, fatigue, peripheral neuropathy, diarrhea, and sleep medication use, whereas university/postgraduate education and chemotherapy cycle T8 were associated with a lower prevalence of poor sleep quality. Conclusions: Nearly half of the patients had poor sleep quality as measured by the PSQI. Poor sleep quality was associated with several demographic and clinical factors, including educational level, other comorbidities, chemotherapy cycle, cancer stage, fatigue, peripheral neuropathy, diarrhea, and sleep medication use. These findings help fill an important evidence gap and support early screening and supportive sleep care for patients undergoing chemotherapy.