Comparative pain and mood effects in patients with comorbid fibromyalgia and major depressive disorder: secondary analyses of four pooled randomized controlled trials of duloxetine.
ABSTRACT The objective of this paper is to better understand the relationship of pain and mood in patients with fibromyalgia and comorbid major depressive disorder (MDD). Pooled data from 4 double-blind, placebo-controlled, randomized trials of duloxetine hydrochloride 60-120mg/day in patients with fibromyalgia were included (N=1332). Of these, 350 (26% [147 placebo, 203 duloxetine]) had comorbid MDD (per Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Text Revision criteria) and were included in these analyses. Primary measures included Brief Pain Inventory average pain; Hamilton Depression Rating Scale or Beck Depression Inventory. Logistic regression was used to evaluate the consistency of treatment effect across various subgroups. Path analysis was used to assess the effect of duloxetine on improvement in pain in the presence of improvement in mood and vice versa. Results indicated that 69% of improvement in pain was a direct effect of treatment, with improvement in mood accounting for 31% of pain response. In conclusion, consistent with our hypothesis, duloxetine produced a substantial direct effect on pain improvement and change in mood exerted a modest indirect effect on pain improvements in patients with fibromyalgia and MDD. Hence, both direct and indirect analgesic and antidepressant properties appear to be relevant for the treatment of these comorbid patients with duloxetine.
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ABSTRACT: Our understanding of the neural correlates of pain perception in humans has increased significantly since the advent of neuroimaging. Relating neural activity changes to the varied pain experiences has led to an increased awareness of how factors (e.g., cognition, emotion, context, injury) can separately influence pain perception. Tying this body of knowledge in humans to work in animal models of pain provides an opportunity to determine common features that reliably contribute to pain perception and its modulation. One key system that underpins the ability to change pain intensity is the brainstem's descending modulatory network with its pro- and antinociceptive components. We discuss not only the latest data describing the cerebral signature of pain and its modulation in humans, but also suggest that the brainstem plays a pivotal role in gating the degree of nociceptive transmission so that the resultant pain experienced is appropriate for the particular situation of the individual.Neuron 09/2007; 55(3):377-91. · 15.77 Impact Factor
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ABSTRACT: The authors conducted an investigation in four tertiary-care centers to determine if psychiatric comorbidity and psychological variables were predictive of functional impairment in patients with fibromyalgia syndrome (FMS). Seventy-three individuals were administered the Structured Clinical Interview for DSM-III-R, the Rand 36-item Health Survey (SF-36), and multiple self-report measures. The patients with FMS were found to have a high lifetime and current prevalence of major depression and panic disorder. The most common disorders were major depression (lifetime [L] = 68%, current [C] = 22%); dysthymia (10% [C only]); panic disorder (L = 16%, C = 7%); and simple phobia (L = 16%, C = 12%). The self-report scales revealed significant elevations in depression, anxiety, neuroticism, and hypochondriasis. Functional impairment on all measures of the SF-36 was severe (e.g., physical functioning = 45.5 and role limitations due to physical problems = 20.0). Stepwise multiple-regression analysis revealed that current anxiety was the only variable that predicted a significant proportion of the variance (29%) in SF-36 physical functioning. Thus, in this multicenter study, the persons with FMS exhibited marked functional impairment, high levels of some lifetime and current psychiatric disorders, and significant current psychological distress. Current anxiety level appears to be an important correlate of functional impairment in individuals with FMS.Psychosomatics 01/1999; 40(1):57-63. · 1.73 Impact Factor