- Email: [email protected]
Dr. Hutto Replies
Letters to the Editor tes.” Diabetes can cause an autonomic neuropathy affecting the pupil just as does syphilis, albeit much less often. Howard L. Berkowitz, M.D. Consultation and Emergency Psychiatry Service, Maimonides Medical Center, Brooklyn, N.Y.
References
1. Hutto B: Syphilis in clinical psychiatry: a review. Psychosomatics 2001; 42:453-460 2. Bouchier IAD, Ellis H, Fleming PR (eds): French’s Index of Differential Diagnosis, 13th edition. Oxford, Butterworth-Heineman, 1996
Dr. Hutto Replies TO THE EDITOR: I wish to thank Dr. Berkowitz for correcting the error I perpetuated in my article. As I noted in the article, the Argyll-Robertson pupil is not very sensitive as a sign of neurosyphilis, and we can now see that it also is not specific. The complex diagnosis of neurosyphilis becomes even a little more difficult with this knowledge. Burton Hutto, M.D. Department of Psychiatry, University of North Carolina School of Medicine, Chapel Hill, N.C.
The Pain-Depression Relationship TO THE EDITOR: In an interesting report, Dickens et al.1 concluded through their statistical analyses that there was no direct relationship between pain and depression and that any relationship is modulated by disability and illness attitude. Unfortunately, although they reviewed some of the literature on this research problem, they appear to have neglected a large body of literature that Psychosomatics 43:3, July-August 2002
argues that there is a direct relationship between the development of pain and the development of depression. In a review,2 we found 37 studies that addressed the relationship between either the severity or frequency of pain and the severity of depression. Of these 37 studies, 33 found a direct statistical relationship between the severity of pain or frequency of pain and the severity of depression. In addition, we investigated whether the literature supported the antecedent hypothesis (depression proceeds development of pain), the consequence hypothesis (depression follows the development of pain), or the scar hypothesis (depression predisposition predisposes to the development of pain). We found 13 studies relating to the antecedent hypothesis.2 Of these, nine did not support the antecedent hypothesis. Fifteen studies were found to relate to the consequence hypothesis. Of these, all 15 (or 100%) were consistent in supporting the consequence hypothesis. Twelve studies were found to relate to the scar hypothesis. Of these, nine supported the scar hypothesis. In addition, six studies utilized structural modeling or path analysis to test the relationship between pain and depression. All six studies (or 100%) found the direction of the relationship to be from pain to depression. Overall this large group of studies were relatively consistent in indicating a direct relationship between pain and the development of depression.2 David A. Fishbain, M.D. University of Miami Comprehensive Pain and Rehabilitation Center, Miami, Florida
References
1. Dickens C, Jayson M, Sutton C, Creed F: The relationship between pain and depression in a trial using paroxetine in sufferers of chronic low back pain. Psychosomatics 2000; 41:490-499
2. Fishbain DA, Cutler R, Rosomoff HL, Steele-Rosomoff R: Chronic pain associated depression: antecedent or consequence of chronic pain? a review. Clin J Pain 1997; 13:116-137
Dr. Dickens Replies TO THE EDITOR: There is no doubt that there is a significant association between pain and depression. This positive association has been demonstrated in numerous studies to date. We briefly reviewed this literature in our introduction and take no issue with this point, highlighted by Fishbain et al. in their comprehensive review of the literature. Interpreting statistical correlations as an indication of a direct (implying causal) link between pain and depression is incorrect, however. The first problem with such an argument is that of the content validity of the measures of depression. The inclusion of biological symptoms of depression (e.g., sleep disturbance, loss of appetite) in such measures results in inflated depression scores, since these items can be endorsed by subjects as a result of their pain syndrome but attributed to a mood disturbance.1 This problem with content validity acts to increase the apparent degree of association between pain and depression. The second problem is that of the role of confounding or moderating (pathway) variables in influencing the association between pain and depression. Statistical correlations do not rule out the possibility that a significant association between variables is confounded or moderated by other variables, i.e., that the association of interest is indirect. Pain sufferers usually experience other associated physical, psychological, and social problems. All of these factors may 341
References
1. Hutto B: Syphilis in clinical psychiatry: a review. Psychosomatics 2001; 42:453-460 2. Bouchier IAD, Ellis H, Fleming PR (eds): French’s Index of Differential Diagnosis, 13th edition. Oxford, Butterworth-Heineman, 1996
Dr. Hutto Replies TO THE EDITOR: I wish to thank Dr. Berkowitz for correcting the error I perpetuated in my article. As I noted in the article, the Argyll-Robertson pupil is not very sensitive as a sign of neurosyphilis, and we can now see that it also is not specific. The complex diagnosis of neurosyphilis becomes even a little more difficult with this knowledge. Burton Hutto, M.D. Department of Psychiatry, University of North Carolina School of Medicine, Chapel Hill, N.C.
The Pain-Depression Relationship TO THE EDITOR: In an interesting report, Dickens et al.1 concluded through their statistical analyses that there was no direct relationship between pain and depression and that any relationship is modulated by disability and illness attitude. Unfortunately, although they reviewed some of the literature on this research problem, they appear to have neglected a large body of literature that Psychosomatics 43:3, July-August 2002
argues that there is a direct relationship between the development of pain and the development of depression. In a review,2 we found 37 studies that addressed the relationship between either the severity or frequency of pain and the severity of depression. Of these 37 studies, 33 found a direct statistical relationship between the severity of pain or frequency of pain and the severity of depression. In addition, we investigated whether the literature supported the antecedent hypothesis (depression proceeds development of pain), the consequence hypothesis (depression follows the development of pain), or the scar hypothesis (depression predisposition predisposes to the development of pain). We found 13 studies relating to the antecedent hypothesis.2 Of these, nine did not support the antecedent hypothesis. Fifteen studies were found to relate to the consequence hypothesis. Of these, all 15 (or 100%) were consistent in supporting the consequence hypothesis. Twelve studies were found to relate to the scar hypothesis. Of these, nine supported the scar hypothesis. In addition, six studies utilized structural modeling or path analysis to test the relationship between pain and depression. All six studies (or 100%) found the direction of the relationship to be from pain to depression. Overall this large group of studies were relatively consistent in indicating a direct relationship between pain and the development of depression.2 David A. Fishbain, M.D. University of Miami Comprehensive Pain and Rehabilitation Center, Miami, Florida
References
1. Dickens C, Jayson M, Sutton C, Creed F: The relationship between pain and depression in a trial using paroxetine in sufferers of chronic low back pain. Psychosomatics 2000; 41:490-499
2. Fishbain DA, Cutler R, Rosomoff HL, Steele-Rosomoff R: Chronic pain associated depression: antecedent or consequence of chronic pain? a review. Clin J Pain 1997; 13:116-137
Dr. Dickens Replies TO THE EDITOR: There is no doubt that there is a significant association between pain and depression. This positive association has been demonstrated in numerous studies to date. We briefly reviewed this literature in our introduction and take no issue with this point, highlighted by Fishbain et al. in their comprehensive review of the literature. Interpreting statistical correlations as an indication of a direct (implying causal) link between pain and depression is incorrect, however. The first problem with such an argument is that of the content validity of the measures of depression. The inclusion of biological symptoms of depression (e.g., sleep disturbance, loss of appetite) in such measures results in inflated depression scores, since these items can be endorsed by subjects as a result of their pain syndrome but attributed to a mood disturbance.1 This problem with content validity acts to increase the apparent degree of association between pain and depression. The second problem is that of the role of confounding or moderating (pathway) variables in influencing the association between pain and depression. Statistical correlations do not rule out the possibility that a significant association between variables is confounded or moderated by other variables, i.e., that the association of interest is indirect. Pain sufferers usually experience other associated physical, psychological, and social problems. All of these factors may 341