VARIATIONS OF LYMPHOCYTE SUBSETS ASSOCIATED WITH STRESS IN DEPRESSIVEPOPULATIONS

Major depression and dysthymia have been associated with increased per ception of day-to-day stressors, greater reliance on emotion-focused c oping efforts, and reduced perception of uplifting events. Moreover, i t has been observed that levels of circulating natural killer (NK) cel ls were elevated in depressed patients. Given that mild stressors may increase circulating NK cells, it is conceivable that the elevated NK cells in depression may be secondary to the increased stress perceptio n associated with the illness. In the present investigation a laborato ry stressor, comprising a mathematical challenge, increased circulatin g NK cells; however, the extent of the increase was comparable in depr essive, dysthymic and control subjects. Moreover, the increased NK cel ls induced by the stressor procedure appeared to be independent of var iations of plasma cortisol, ACTH or norepinephrine. Interestingly, alt hough the NK changes were not differentially influenced by stressors i n the subject populations, in the major depressive patients correspond ence existed between NK cell levels and emotion-focused coping styles. Likewise, the response to a laboratory stressor was directly related to the severity of depression and to the use of coping styles involvin g cognitive restructuring or problem solving. (C) 1997 Elsevier Scienc e Ltd.