Managing Fatigue in the Syncope Unit

Julia L. Newton


Europace. 2012;14(12):1696-1699. 

In This Article

Autonomic Dysfunction in the Pathogenesis of Fatigue

In a range of diseases where fatigue is well-recognized such as multiple sclerosis and Parkinsons disease, strong associations have been seen between the presence and severity of fatigue and autonomic dysfunction[10,11] underlining the importance of autonomic dysfunction in the pathophysiology of fatigue and the potential for overlap with neurally mediated syncope.

Studies performed in our population have shown that patients with vasovagal syncope are significantly more fatigued compared with matched controls and that those who continue to have syncopal episodes are more fatigued than those whose syncopal episodes have been successfully treated.[12] Furthermore, fatigue is recognized as a prominent symptom in conditions associated with autonomic dysfunction such as primary autonomic failure and multi-system atrophy, diseases which are characterized by abnormalities of blood pressure control.[13]

In addition, more recently in fatigue-associated diseases such as primary biliary cirrhosis,[14] non-alcoholic fatty liver disease,[15] early renal disease,[16] and Sjögrens syndrome,[17] fatigue has been recognized, quantified, and associations with autonomic symptoms and objectively measured autonomic function have been confirmed.

This strongly supports a hypothesis that autonomic dysfunction represents a common pathogenetic mechanism for both syncope and fatigue.