Fatigue severity and fatigue sensitivity: relations to anxiety, depression, pain catastrophizing, and pain severity among adults with severe fatigue and chronic low back pain.

Chronic low back pain is the second leading cause of disability in the United States, and it is often associated with severe fatigue. However, little is known about individual differences that may be related to poorer mental health and pain among individuals with severe fatigue and chronic low back pain. The aim of the current investigation was to explore the role of fatigue severity and fatigue sensitivity in terms of anxiety and depressive symptoms, pain catastrophizing, pain interference, and pain severity among 783 adults with severe fatigue and chronic low back pain. Results suggest that fatigue severity and fatigue sensitivity were statistically significant predictors for anxiety, depression, pain interference, and pain catastrophizing. However, only fatigue sensitivity significantly predicted pain severity. Overall, the current study provides initial support for the role of fatigue severity and fatigue sensitivity in the presence of mental and physical health complaints among individuals with severe fatigue and chronic low back pain.