From Vlaeyen & Linton 2000
In the first blog of this series, I reviewed concerns with how the model is used clinically (read it here). Now, let’s look in-depth at the fear avoidance model to the right, it’s reformation depicted below, and the research surrounding the basic assumptions driving the relationship and pathway from pain to disability. The diagram shows pain leading to an infinite loop of worry, leading to fear, vigilance, disuse and disability. It assumes that removing the catastrophic thinking, and thus removing fear, followed by exposing the person to the painful activity, leads to recovery. It is premised on the idea that without worry, there is no fear, and no disability.
Lee et al performed a systematic review and meta-analysis of the pain-disability relationship. The model above is unidirectional and implies causality. They found that the proposed pathway of fear avoidance (pain>catastrophic thoughts>fear>disuse>disability,) is not supported by the evidence. When looking at the relationship of pain on disability, catastrophic thinking did not mediate the relationship. Fear mediated the effect of pain on disability but did not mediate the relationship between catastrophizing and disability. Pincus et al 2006 also could not confirm in their systematic review that fear was predictive of a poor outcome. Even the architects of the model did not find evidence in support of the relationship between catastrophic thinking and disability being mediated by fear of movement.(Leeuw et al 2007) Pincus et al 2010 noted “Although changes both in fear and in catastrophizing predicted return to work, there was no significant sequential relationship between changes in catastrophizing at early stages and changes in fear later on.” (p741)
Lee et al, Wideman et al, and Woby et al (and others not cited here) have stated that self-efficacy was the strongest mediator of the pain/disability relationship. Woby et al also noted that if self-efficacy is high, then elevated fear won’t decrease function. If self-efficacy is low, then pain related fear will have a greater impact. Costa et al found similarly. They investigated prospectively over the course of a year. While fear of movement and self-efficacy were both relevant at onset and initial development of disability due to persistent pain, the same was not true one year later. At that time, self-efficacy mediated disability. While fear of movement can predict functional outcomes in the presence of low self-efficacy, fear of movement ceases to predict reduced function, in the presence of high self-efficacy. This leads me to conclude that early on, addressing fear of movement and self-efficacy is useful. If pain evolves to persistence, self-efficacy is a better treatment target.
Crombez et al sought to elaborate on updating the fear avoidance model. They persist with the tenet that within the fear avoidance model, a person is “trapped into a vicious circle of chronic disability and suffering.“ (p475) Who wants to explain to someone suffering that they are “trapped in a vicious cycle” brought on by fear-based beliefs? What does a clinician educating a patient about this, say? “If you don’t start doing some of these things you will get trapped in a viscous cycle”? Please don’t do that. And, the evidence does not support this as truth. They thankfully recognized that “erroneous beliefs” about pain are pervasive and normal, and not irrational. They identified that conflating this model as phobia-based has led to perpetuation of perspectives that patient’s fears are irrational. They acknowledged that the phenomenon seen with persistent pain is aligned with worrying when no clear resolution is apparent rather than with “catastrophic thinking”. They state that pain interference may be what leads to distress. Not feeling in control, not perceiving that one has agency, is unsettling. It would be useful to update the model to reflect “worry” instead of catastrophic thinking. Unfortunately these terms still persist in many papers about fear avoidance, and in clinical practice. I think changing nomenclature could help clinicians connect better with patients. They aren’t “catastrophizing”, they are worried. They note that missing from the model are modifiers of coping, persistence, acceptance, and goal pursuit/failure/adjustment.
hi-res link here
In 2016, developers of the model published an updated version. In their past research, they have discussed the contextual nature of pain, but the updated model hasn’t been reformatted to reflect this. They continue to hold on to temporal and causal relationships that have not been verified. The model ignores the moderating effect that self-efficacy has on the pain/disability relationship. The proposed pathway begins with nociception leading to the pain experience. We know this is not true. In their writing, they continue to perpetuate that for recovery to occur, the focus should be on resolving avoidance and fear based beliefs. Self-efficacy has been demonstrated to do this, and the model should say so. Catastrophic thinking has been changed to “negative affect” while not mentioning “worry” as they had previously identified. It remains conceptually inaccessible to clinical application of rehabilitation practitioners with a fixation on conditioned responses leading to pain persistence. The year after this reconceptualization, Boselie and Vlaeyen mention “protective factors” and “vulnerability factors” with limited expansion of how it impacts the model. While this terminology may be more helpful, it requires further development.
In the next installment of this series, future exploration and it’s understanding for clinical application, will be discussed.
Boselie, J. J., & Vlaeyen, J. W. (2017). Broadening the fear-avoidance model of chronic pain? Scandinavian Journal of Pain, 17(1), 176-177. doi:10.1016/j.sjpain.2017.09.014
Costa, L. da C. M., Maherl, C. G., McAuleyl, J. H., Hancockl, M. J., & Smeetsl, R. J. E. M. (2011). Self-efficacy is more important than fear of movement in mediating the relationship between pain and disability in chronic low back pain. European Journal of Pain, 15(2), 213–219.
Crombez G, Eccleston C, Van Damme S, Vlaeyen JWS, Karoly P. Fear- avoidance model of chronic pain: the next generation. Clin J Pain 2012; 28:475–83.
Lee, H., Hübscher, M., Moseley, G. L., Kamper, S. J., Traeger, A. C., Mansell, G., & Mcauley, J. H. (2015). How does pain lead to disability? A systematic review and meta-analysis of mediation studies in people with back and neck pain. Pain, 1.
Leeuw, M., Houben, R., Severeijns, R., Picavet, H., Schouten, E. and Vlaeyen, J., 2007. Pain-related fear in low back pain: A prospective study in the general population. European Journal of Pain, 11(3), pp.256-266.
MJ,SullivanMJL,HaythornthwaiteJA,EdwardsRR. Rethinkingthefear avoidance model: toward a multidimensional framework of pain-related disability. PAIN 2013;154:2262–5.
Costa, L. da C. M., Maherl, C. G., McAuleyl, J. H., Hancockl, M. J., & Smeetsl, R. J. E. M. (2011). Self-efficacy is more important than fear of movement in mediating the relationship between pain and disability in chronic low back pain. European Journal of Pain, 15(2), 213–219.
Vlaeyen, J., Crombez, G. and Linton, S., 2016. The fear-avoidance model of pain. PAIN, 157(8), pp.1588-1589.
Wideman TH, Adams H, Sullivan MJL. A prospective sequential analysis of the fear-avoidance model of pain. PAIN 2009;145:45–51.
Wideman TH, Asmundson GGJ, Smeets RJEM, Zautra AJ, Simmonds MJ,SullivanMJL,HaythornthwaiteJA,EdwardsRR. Rethinking the fear avoidance model: toward a multidimensional framework of pain-related disability. PAIN 2013;154:2262–5.
Woby, S. R., Urmston, M., & Watson, P. J. (2007). Self-efficacy mediates the relation between pain-related fear and outcome in chronic low back pain patients. European Journal of Pain, 11(7), 711–718.
©2020 DevraJoy LLC. All rights reserved.