Correlations among traditional Chinese medicine constitutions, sleep quality, and cancer-related fatigue in patients with breast cancer

Purpose To investigate the status of Traditional Chinese Medicine (TCM) constitution, sleep quality, and Cancer-Related Fatigue (CRF) in breast cancer (BC) patients and explore the relationships among these three factors, thereby providing a basis for reducing the level of CRF in individuals with BC. Methods BC patients were enrolled from two Tertiary Level-A Hospitals in Shandong Province, China, using convenience sampling. Data were collected using the General Information Questionnaire, the Self-Measurement Scale for the Classification and Determination of TCM constitutions, the Pittsburgh Sleep Quality Index (PSQI), and the Piper Fatigue Scale (PFS). Results A total of 320 breast cancer patients were included, predominantly exhibiting unbalanced constitutions (72.19%). Correlation analysis indicated that a balanced constitution was negatively associated with cancer-related fatigue (CRF) ( r = −0.461, P < 0.01), In contrast, Qi deficiency, Yang deficiency, phlegm-dampness, dampness-heat, Qi stagnation constitutions, and poorer sleep quality were positively correlated with CRF (all P < 0.01). Multiple linear regression identified Qi deficiency, Yang deficiency, and Qi stagnation as significant independent predictors of CRF ( P < 0.05). Furthermore, structural equation modeling revealed that sleep quality partially mediated the relationship between CRF and these three constitutions, with mediation proportions of 22.47%, 22.52%, and 37.5%, respectively. Conclusions The level of CRF in patients with BC is moderate and multifactorial. Therefore, medical personnel can alleviate CRF by addressing patients' unbalanced constitutions to improve sleep quality.