PSYCHOLOGICAL DYSFUNCTION IN PATIENTS WITH REFLEX SYMPATHETIC DYSTROPHY

Patients with reflex sympathetic dystrophy (RSD) often present with pa in and disability that cannot be explained on the basis of objective p hysical findings. This has led some to speculate that RSD may be cause d or mediated by non-organic factors. Unfortunately, there have been f ew studies using standardized measures of mood and illness behavior th at have compared patients with RSD to patients with other chronic pain disorders. The goal of the present study, therefore, was to compare t he pattern of psychological dysfunction in patients with RSD to the pa ttern of dysfunction in patients with chronic back pain and local neur opathic pain. Patients with back pain resemble those with RSD in that both may report symptoms that cannot be reconciled with objective phys ical findings. Patients with local neuropathy, by contrast, report pai n that is both circumscribed and consistent with a known organic cause . The records of 253 patients attending a tertiary pain service were r etrospectively reviewed and three distinct (non-overlapping) diagnosti c groups were formed: 25 were assigned to the RSD group; 44 to the bac k pain group; and 21 to the local neuropathy group. Using a set of str ingent criteria to diagnose RSD and an analysis of covariance to contr ol for differences in symptom duration and age, the present study foun d no evidence to suggest that patients with RSD were psychologically u nique. Instead, RSD patients were remarkably similar to those with loc al neuropathy in terms of their symptom reporting, illness behavior, a nd psychological distress. The only exception was that RSD patients ha d more disability days during the preceding 6 months than those with l ocal neuropathy (P < 0.05). The back pain group, on the other hand, pr esented with more diffuse pain complaints (P < 0.05) and had a greater number of non-specific medical symptoms (P < 0.05) compared to either the RSD or local neuropathy group. In contrast to previous research u sing less stringent diagnostic criteria, there was no evidence of high er pain scores or lower levels of psychological distress among patient s with RSD. In addition, a validated survey of childhood trauma found that sexual abuse, physical abuse, emotional abuse, and cumulative tra uma were evenly distributed among all three diagnostic groups. The bur den of proof would appear to be upon those who advocate the non-organi c hypothesis to provide credible evidence of psychological involvement in the etiology of RSD. (C) 1997 International Association for the St udy of Pain. Published by Elsevier Science B.V.