RELATIONSHIPS OF BETA-ENDORPHIN, LEVEL OF PAIN AND DEPRESSIVE STATE IN PATIENTS WITH RHEUMATOID ARTHRITIS.

Abstract

This study was designed to assess the correspondence among plasma beta-endorphin, pain and depression and the effect of Expressive Release Therapy on levels of beta-endorphin in women with rheumatoid arthritis. An inverse linear relationship was anticipated between beta-endorphin and pain, and a linear relationship was anticipated between beta-endorphin and depression. Treatment was expected to produce an ongoing increase in beta-endorphin and a corresponding decrease in pain. Six women, aged 26-68, with rheumatoid arthritis in Stage II or III participated in this A-B with follow-up replicated design. Plasma beta-endorphin was measured by radioimmunoassay, pain levels were reported on a visual analogue scale and depression was assessed by the Beck Depression Inventory. The treatment protocol was implemented by two experienced therapists, each of whom provided individual therapy to three of the subjects. The design consisted of a four week baseline control, a ten week treatment, and a four week follow-up period. Subjects were assessed on the pain and beta-endorphin measures at the beginning (pre-session) and the end of an hour (post-session) at the same time each week. The depression measure was completed at pre session. Results were analyzed by visual analysis, Pearson product-moment correlations and repeated measures analyses of variance. A significance level of .10 was selected. Although suggestive of an inverse relationship, most of the correlations between pain and beta-endorphin were too low to justify firm conclusions. The findings also failed to demonstrate a consistent linear relationship between beta-endorphin and depression. Visual analysis demonstrated that pre-session beta-endorphin levels temporarily increased during the early and late weeks of treatment. Statistical analyses failed to demonstrate a significant overall effect of treatment; however, contrary to our predictions, post-session beta-endorphin levels were significantly lower than pre-session levels across all phases of the study. Treatment failed to produce a significant effect on pain levels; however, visual analysis revealed that pain levels tended to be lower at post-session across all phases of the study. The current data suggested that plasma beta-endorphin is not directly related to pain in rheumatoid arthritis and that beta-endorphin may function as an indicator of stress. In addition, the treatment appeared to produce periodic and temporary increase in beta-endorphin not accompanied by a decrease in pain.