Rosomoff Rs

Do antidepressants have an analgesic effect in psychogenic pain and somatoform pain disorder? A meta-analysis.

Objective A significant amount of evidence indicates that some antidepressants have an analgesic effect. We wished to determine whether this analgesic effect could be demonstrated in studies that had used antidepressants for the treatment of pain in patients diagnosed with psychogenic pain or somatoform pain disorder. Meta-analysis was used for this purpose. Methods All randomized, placebo-controlled antidepressant treatment studies of patients diagnosed with psychogenic pain disorder or somatoform pain disorder were isolated. These studies were reviewed and relevant statistics were coded. For each study, a single p value for the drug/placebo comparison was found or calculated for pain change scores from pretreatment to completion of treatment. The z scores and effect sizes were calculated for each study, followed by a calculation of an overall z score and effect size. Results Eleven studies fulfilled the inclusion and exclusion criteria for this meta-analysis. The combined difference showed that antidepressants decreased pain intensity in patients with psychogenic pain or somatoform pain disorder significantly more than placebo (z = 5.71, p < .0001). The overall effect size was large (mean = 0.48) and ranged from 0 to 0.91. Conclusions The results indicate that, in patients diagnosed with psychogenic pain or somatoform pain disorder, antidepressant treatment resulted in a reduction in pain that was significantly greater than that of placebo. Possible explanations for these results are discussed.

Functional electrical stimulation treatment of postradiculopathy associated muscle weakness.

Eighteen chronic pain patients (CPPs) with postradiculopathy-associated muscle weakness were entered into a nonrandomized functional electrical stimulation (FES) clinical treatment study to determine if FES can improve postradiculopathy associated muscle weakness. Because of the clinical nature of the unit, the CPPs could not be denied treatments other than FES. To control for these other treatments, the CPPs were used as their own controls with two control conditions, ie, where possible, the contralateral probable normal muscle was used as a control (control 1) and; in a subgroup of CPPs (n = 6), FES treatment was initially withheld to the probable weak muscle (control 2). Strength was measured as isometric maximum voluntary contraction (IMVC) and was used as the outcome treatment variable. IMVC was measured in both the probable weak and contralateral probable normal muscles at entrance into the Pain Center, at beginning of FES treatment, at completion of FES treatment, and for the control 2 condition at the end of the non-FES treatment period. Statistical analyses of the IMVC strength results using the two control conditions indicated (1) both the FES-treated and untreated muscles increased significantly in IMVC strength, (2) improvement in IMVC strength for FES-treated muscles was significantly greater than for probable normal FES-untreated muscles and, (3) improvement in IMVC strength in FES-treated muscles was significantly greater during the FES-treatment period than during the non-FES treatment period. FES treatment of postradiculopathy-associated muscle weakness in CPPs seems to increase the strength of the probable weak muscle above the increase in strength provided by other concurrent treatments.(ABSTRACT TRUNCATED AT 250 WORDS)