Fatigue is a complex complaint and it remains a challenge to explore, as the precise cause of fatigue remains unclear. The most widely accepted proposed cause of fatigue in MS is the notion of the 'neurogenic hypothesis,' which considers that increased intracranial pressure (ICP) in MS causes a release of dopamine, which in many ways can be analogous to the dopamine released from the brain stem during sleep, leading to a feeling of fatigue. Recent evidence have shown that fatigue is not in fact associated with a higher ICP, nor with increased dopamine levels.
Fatigue is a complicated condition, involving many different factors, including physical, psychological, medical, and environmental. The common symptom is the inability to concentrate, or to complete tasks, normally achievable in the days before the onset of fatigue. The brain's need for oxygen, glucose, and ATP is often hampered during sleep in this disorder.
Patients whose symptoms of fatigue were alleviated, the severity of fatigue diminished, and their fatigue perceived as worse by patients who had fatigue that was not cured are candidates to receive fatigue-resolving treatments.
Symptoms of fatigue include: lethargy or feeling tired most of the time, being unable to do one's usual tasks for a long time, feeling tired in one's muscles, and a general feeling of weakness. Symptoms of fatigue last for more than two weeks and signify a prolonged state and can be severe, such as the case of patients in cancer or neurological conditions. In the present study, the correlations and relationships among depressive symptoms with fatigue symptoms were weak. The effect of depressive disorders on fatigue symptoms warrants further studies.
More than 1 billion women and men are affected by fatigue in the United States. These patients experience physical and mental health conditions that, in part, arise from reduced overall productivity, with reduced efficiency and productivity losses of US$15.5 billion per year.
Physical factors like sleep deprivation and fatigue are not an uncommon problem in clinical practice. Patients should be encouraged to sleep well and get regular exercise. Physical activities such as yoga and yoga therapy can help many patients achieve a feeling of "mental energy". This is in agreement with the fact that yoga is an easy way to gain a feeling of "physical energy".
[Systematic light exposure was not effective in changing fatigue outcomes among women with cancer in our study. It is possible that low methodological quality, small sample size, and low adherence with the treatment method may be the reasons explaining our results.
In a recent study, findings demonstrates three important aspects: 1. The existence of primary fatigue may be clinically significant; 2. The possibility that the symptom may relate to multiple organic and psychological causes might offer a new target for evaluating primary and/or "secondary" fatigue; and 3. A more effective method to identify a patient's etiology may be required to improve the efficiency and effectiveness of patient management.
The magnitude of intervention effect on objective physical fatigue-burden, activity-intensity, and fatigue-burden may be limited by a small effect on self-reported sleep quality at the intervention site.
This small sample study highlights the need for improved standardisation in defining and administering intervention light exposure in studies. Although the intervention was beneficial, our data does not show the clinical impact of light therapy as a treatment. Further prospective studies with a similar intervention as used in this study are required.
In people over 65, FQS and WQS are often used as scales for estimating levels of fatigue in older adults. However, for younger children, the concept of mild fatigue is not applicable. [See comments/concern section.
Current research in fatigue is focused mainly on fatigue pathophysiology, as reported in numerous scientific articles and scientific abstracts. However, there are many unresolved questions in this area which could help to develop more effective interventions.