[Psychosomatic medicine in rheumatoid arthritis]

Recent studies have shown that neuropeptides, such as substance P, are responsible for arthritis. We therefore studied opioid peptides (beta-endorphin, Methionine-enkephalin, Leucine-enkephalin) in order to confirm our belief that mental status may have some influence on the activity of rheumatoid arthritis (RA). We examined opioid peptides, lymphocyte subsets, psycologic test (Cornell Medical Index-Health questionnaire (CMI), the Face scale) and clinical data in patients with RA. Plasma Leu-enk, % Leu2a+ Leu15- cells,% Leu3a+ Leu8- cells and % Leu11+ Leu7- cells were higher in patients with a larger number of psycologic complaints in CMI. Plasma Leu-enk concentration was higher while % Leu11+ Leu7- cells was lower in proportion to the degree of neurosis, as indicated by the descrimitive chart of CMI. Plasma Met-enk concentration, % Leu2a+ Leu15- cells, and Lansbury's index were significantly higher in the group of patients whose facial expression was more severe. These findings suggest that mentala status have some relationship with the plasma level of opioid peptides (enkephalins) and immunologic functions, and that it may exert indirect effects on RA.