Recent research has implicated anxiety sensitivity (AS), the fear of anxiety-related sensations, as a mitigating factor involved in fear and avoidance in patients with chronic back pain [Understanding and treating fear of pain (2004) 3]. Given reported similarities between individuals experiencing chronic pain and those experiencing recurrent headaches, it is theoretically plausible that AS plays a role in influencing fear of pain and avoidance behavior in people with recurrent headache. This has not been studied to date. In the current study we used structural equation modeling to examine the role of AS in fear and avoidance behavior of patients experiencing recurrent headaches. Treatment seeking patients with recurrent headaches completed measures of AS, headache pain severity, pain-related fear, and pain-related escape and avoidance behavior. Structural equation modeling supported the prediction of a direct significant loading of AS on fear of pain. Headache severity also had a direct loading on fear of pain. Results also revealed that AS and headache severity had indirect relationships to pain-related escape and avoidance via their direct loadings on fear of pain. Headache severity also had a small direct loading on escape and avoidance behavior. These results provide compelling evidence that AS may play an important role in pain-related fear and escape and avoidance behavior in patients with recurrent headaches.
The results of the structural equation modeling provide preliminary, albeit not perfect, support for a similar model to that found by Asmundson and Taylor (1996). Our model, consistent with the Asmundson and Taylor (1996) model, identified AS as having a direct significant relationship to fear of pain in patients with recurrent headaches. Pain severity had a direct significant loading on fear of pain, albeit of a slightly smaller magnitude than AS. Again, this finding was observed by Asmundson and Taylor (1996). As predicted, our model converged with Asmundson and Taylor's in that fear of pain had a very strong direct loading on pain-related escape and avoidance behavior. Contrary to their results, however, we found that pain severity had a small but significant direct loading on pain-related escape and avoidance behavior after accounting for the indirect loading via fear of pain. This discrepancy between our model and that of Asmundson and Taylor (1996) may indicate some differences between the experiences of chronic headache and musculoskeletal pain.
In conclusion, our results generally support the Asmundson and Taylor (1996) model when employed with a sample of patients experiencing recurring headache. Pain severity and AS both significantly influenced fear of pain, and fear of pain significantly influenced headache-related escape and avoidance behavior. In addition, pain severity had a direct, albeit small, loading on escape/avoidance behavior. These results suggest that treatment strategies that directly target AS may effectively diminish escape and avoidance behaviors in patients seeking treatment for recurrent headache.