3.1 Sleep quality of patients after renal transplantation.
The study results showed that the PQSI score of patients after kidney transplantation was (5.31 ± 2.47), indicating the existence of mild to moderate sleep disorder, indicating that patients after kidney transplantation still have sleep disorder problems. Secondly, the PQSI score of patients after kidney transplantation is lower than domestic standards(11). The reason may be that the kidney transplant patients included in this study were transplanted for one year or more. As kidney function returned, her sleep improved. Previous studies have shown that a significant decrease in patients’sleep quality scores was observed at 6-month follow-up after kidney transplantation, and a significant decrease in patients’ sleep quality scores was observed at 6-month follow-up after kidney transplantation(2).. Another study reported that kidney transplantation had no effect on sleep quality during one year of follow-up(12). Therefore, the developmental trajectory of sleep quality in patients after renal transplantation requires further study.
3.2 Correlation between sleep quality, depression and fatigue in patients after renal transplantation.
The results of this study show that there is a significant positive correlation between the total PSQI score and the total PHQ score of patients after kidney transplantation (r = 0.422, P<0.01). In other words, the worse your depression is, the worse your sleep quality will be. Depression is a significant mood change manifested by symptoms such as weight loss, decreased energy levels, and reduced physical activity(13). Among kidney transplant patients, 18–22% develop depressive symptoms after surgery(14). These depressive symptoms are important markers of frailty and are independently associated with adverse outcomes after kidney transplantation, including poor medication compliance, recovery from dialysis treatment, graft failure, cardiovascular mortality, and all-cause mortality(15).Therefore, during the patient’s emotional and psychological fluctuations, the patient’s sleep quality is greatly affected. Correlation analysis showed that sleep quality was significantly positively correlated with fatigue. Our results are consistent with those of Rodrigue et al(16). In other words, the more tired the patient is, the worse the sleep quality is. Symptoms associated with fatigue include inflammation, depressive symptoms, sleep problems, and obesity. Fatigue can lead to severe renal damage, which is common in renal transplant patients with poor compliance with immunosuppressive therapy and is associated with severe deterioration in quality of life(17). Previous studies have also suggested that fatigue severity is closely related to sleep quality disorders, which significantly affects patients’sleep quality(18).
3.3 The mediating role of depression between fatigue and sleep quality.
The results of this study indicate that fatigue not only directly affects the sleep quality of patients after kidney transplantation, but also indirectly affects the sleep quality of patients through the mediating effect of depression. Depression is closely related to fatigue and sleep quality. Previous research has shown that symptoms of depression include sleep disturbances. However, as research continues, it has been discovered that there is a bidirectional relationship between depression and sleep disorders(19).
This study also confirms that there may be bidirectional effects between depression and sleep quality. The study by Gebaba et al.(20)pointed out that almost 80% of patients with depression are accompanied by varying degrees of sleep disorders. Sleep disorder patients with disrupted sleep rhythms are more likely to develop depression than patients with normal sleep. Fatigue is a complex, multifaceted phenomenon determined by physical, psychological, and emotional factors(21). Fatigue can also be described as a condition that causes pain or decreased physical function, resulting in a loss of energy(17).
Many patients continue to experience symptoms of fatigue and weakness after a kidney transplant. Therefore, physical and mental fatigue can affect patients’ mood swings, leading to anxiety and depression. The results of this study will encourage medical staff to not only promote patients’ physical health in daily care, but also consider patients’mental health and promptly identify patients’ negative emotions. We also need to provide patients with effective mental health maintenance and improve sleep and quality of life.