To the Editor:
Fitzcharles, et al1 point out that fibromyalgia (FM) patients with disability have more symptoms and require more medications compared to those who are working. The authors review well the broad issues concerning disability in this population. They rightly surmise that motivation to remain in the workforce may be lacking for some and may be influenced by the workplace environment — those with less-satisfying jobs will be less motivated to continue working. We think that issues of motivation and the high endorsement of symptoms for the purpose of accessing disability are even more important than recognized by clinicians and may be overlooked in disability evaluations.
As published previously in The Journal, Gervais, et al2 examined the importance of symptom exaggeration as a factor in complaints of cognitive dysfunction in patients with FM. Ninety-six patients with FM and 16 patients with rheumatoid arthritis (RA) were administered 2 effort or symptom validity tests designed to detect exaggerated complaints. A large percentage of patients with FM who were receiving or seeking disability benefits failed the effort tests. Only 2 patients with FM who were working and/or not claiming disability benefits, and no patient with RA, scored below the cutoffs for exaggeration of memory difficulties. Indeed, the patients with FM scored below the mean achievement of individuals with moderate to severe traumatic brain injuries or neurological diseases. Yet, as has been shown, when subjects who fail these so-called “effort tests” are then told that these tests are designed to detect exaggeration, subjects routinely pass them3,4. It is important to point out that the study by Gervais, et al does not show that FM is strongly associated with symptom exaggeration, response bias, or suboptimal effort. On the contrary, response bias was almost nonexistent in the FM group not claiming disability. What this study does show is that disability claims are associated with response bias and potential symptom exaggeration in a significant minority of cases.
We suggest that the reason that FM patients with disability have more symptoms and more severe symptoms (as shown by Fitzcharles, et al) cannot be directly assumed to be the disability itself, but more probably reflects the mechanisms by which patients who are motivated, consciously or not, to seek a successful disability application can achieve the desired impression.
FM is an illness characterized in part by a lack of face validity. Symptoms are the only currency patients have for their interaction with clinicians and disability evaluators. For this reason, effort testing and symptom exaggeration testing are essential in assessing patients with FM presenting for disability-related evaluations.
