Haemodialysis treatment in uremic patients: investigation of the correlation between depression, reward system and chronic fatigue

Haemodialysis is considered a life-saving treatment, allowing a good level of survival for uremic patients waiting for organ transplant. Uraemia, if not addressed in an adequate manner, can lead to death. However, treatment greatly influences the patient’s life. Eighty percent of patients has chronic fatigue, affecting the quality of life (QoL). Fatigue is a multidimensional symptom. The “physical” dimension is linked to obvious bodily limitations, but recovery mechanisms save all of their effectiveness, allowing to get the strength back as a result of an adequate rest period. The “motivational” dimension, however, is more complex and refers to a central fatigue, often associated with pain, disturbed sleep, affective and cognitive disorders. In spite of studies carried out in groups of patients with chronic disease, suggest that psychological interventions to decrease the fatigue is necessary, these interventions are not available for haemodialysis patients. The aim of this study is to evaluate the level of fatigue, assuming a comorbidity with a past of anxiety and depression, and how the motivation mechanisms are affected with a significant impact on QoL. Evaluative scales have been administered to a sample of haemodialysis patients (N=94) older than 18 years, with no neurocognitive disease. Fatigue Severity Scale (FSS) has been applied to measure the impact of fatigue on motivation and social functionality. BIS/BAS Scale has been administered to investigate the mechanisms of reward: Behavioural Activation System (BAS) and Behavioural Inhibition System (BIS) result in behavioural inhibition/activation to rewards/punishments. Finally, the State-Trait Anxiety Inventory (STAI-Y) and the Back Depression Inventory (BDI-II) have been used to evaluate the potential presence of anxiety and depression disorders. For a qualitative analysis, a semi-structured interview has been performed. The results show a linear correlation between the fatigue and depression level: a. Fatigue is directly proportional to symptoms such as sadness, frustration, irritability, difficulty concentrating and loss of interest. b. The inclination to act, led by the BAS system, is inversely proportional to depression. Therefore, its indirect correlation with chronic fatigue is conceivable. c. The BIS system, on the other hand, is directly related to the sense of fatigue, especially in men. This study shows that the sense of fatigue is not exclusively linked to pathophysiologic factors of uraemia and haemodialysis but to a central fatigue on a psychological level. A psychosocial intervention would be useful to improve the QoL of the haemodialysis patients, lessening the “fatigue” symptom.