Fatigue is a frequent symptom shared by all patients on long-term dialysis (
15). Joshwa et al. reported fatigue in 75% of the patients on hemodialysis (
24); in the current study, 65.2% of the patients had experienced fatigue.
In this study, there was a significant difference between the fatigue scores in the experimental group before and after the intervention, which was due to intradialytic mental and physical exercises for two months. The study conducted by Riahi et al. demonstrated significant reduction in the fatigue level after five months of intradialytic use of leg ergometric exercises, which was in line with the findings of the current study (
26). In study of Yurtkuran et al., a significant improvement was observed in the patients’ fatigue after 12 weeks of yoga exercises (
27). This is in contrary to the fact that the study had cost the patients their extra time by being performed in a time other than the dialysis hours. Chang et al. reported a significant reduction in the fatigue level after eight consecutive weeks of intradialytic use of leg ergometric exercises (
18), while the current study did not require using any special tool and was easily conducted in an occupied space of the hospital ward.
In our study, no significant correlation was observed between patients’ sex and fatigue. There is evidence indicating that fatigue in women happens with greater sequence and severity in comparison with men; however, it was not confirmed by all the studies conducted so far (
16). The study by Chang demonstrated no significant difference between sex and the fatigue or physical activity (
18), while in the study by Liu the fatigue was greater in women than men (
28).
Age served as a variable predicting the fatigue in our study. With age, the total score for fatigue increased; however, Chang et al study (
18) had considered physiological changes due to the effect of a chronic disease as the cause of increase in fatigue with age.
Although the spouses of the patients on hemodialysis played a supporting role in reducing the stress, adapting to the disease, following the treatment, and reducing the weakness, the findings of some studies were not indicative of any significant difference between fatigue severity and marital status (
29), which were in agreement with the findings of the current study.
Compared to the employed individuals, the unemployed ones exhibited greater fatigue in our study, which was confirmatory to the findings by Liu (
28). Increase in motivation as well as social interactions, decrease in the fatigue occurrence, lack of concern for economic problems, and increase in the level of activity might justify the reduction in the fatigue among the employed individuals. On the contrary, staying at home led to a reduction in the physical activity and losing the colleagues’ social support. Thus, the unemployed patients might report a higher level of fatigue.
Having the benefit of higher education allowed the patients to employ fatigue-reducing solutions. The findings of a previous study indicated that as the level of education increased, the subjects’ fatigue decreased (
29). In the current study, the illiterate and the university educated subjects reported the highest and the lowest level of fatigue, respectively; however, the difference was not statistically significant.
The present study demonstrated that patients with less than 24 months since their dialysis exhibited greater fatigue, while according to Liu’s study, no correlation existed between the duration of dialysis and any of the fatigue dimensions (
28). Interestingly, the study by Letchmi et al. pointed toward a significant correlation between fatigue and duration of dialysis (
30), which was in accordance with the findings of the current study. Therefore, the negative correlation between the duration of dialysis and fatigue might be indicative of the fact that patients undergoing dialysis for less than two years were not yet capable of developing coping behavior in line with the treatment.
Diabetes is identified as the single most common cause of gradual loss of kidney function (
31). Based on the findings of the present study, diabetes was the most common cause of renal failure; however, it was not statistically significant. Furthermore, individuals with diabetes exhibited more fatigue possibly because of the disease process and its ensuing consequences. The study conducted by Raimann et al. demonstrated that postdialysis fatigue is more severe in patients with diabetes than other patients (
32). One of the reasons of fatigue in diabetes is fluctuations in blood glucose levels. Fatigue may also be correlated to psychological factors, such as depression or emotional problems related to the diagnosis or to the intensity of diabetes self-management regimens. Fatigue may also be related to such lifestyle methods as lack of physical activity or being overweight (
33).
In Conclusion, the positive effects of exercise, regarding performance time and method, on improvement of the quality of life, reduction of cardiovascular complications, mortality rate, depression, sleep, and fatigue has been documented clearly. The present study showed that simple intradialytic physical and mental exercises programs, with no need to expensive and highly-morbid procedures, can decrease the fatigue in patients on hemodialysis. Therefore, this therapeutic method is recommended for this group of patients.