Last years have brought important informations about the changes in white blood cell parameters in patients with depressive disorder and furthermore changes in the levels of cytokine production. The concept of bidirectional communications between the immune system and the central nervous system has been expressed as the 'macrophage theory of depression' and the 'cytokine hypothesis of depression' that described greater expression of monocyte-associated Interleukin-1beta (IL-1beta), Interleukin-1(see text for symbol) (IL-1(see text for symbol)), tumor necrosis factor-alpha (TNF-alpha), Interleukin-6 (IL-6), Interleukin-8 (IL-8) etc., in patients suffering from depression. It was supported by many findings e.g. administration of proinflammatory cytokines in the treatment of cancer and hepatitis C, that induced depressive symptomatology. Generally Depression accompanies a number of illnesses characterized by chronic inflammatory response. The aim of this study was to investigate the association between intensity of depression and blood cells counts in patients attending Rheumatology Department.
Research included 56 patients hospitalized in Department of Rheumatology (Medical University of Bialystok), by the reason of rheumatic arthritis (RA), systemic lupus erythematosus (SLE), ankylosing Spondylitis (AS), systemic scleroderma, Churg-Strauss syndrome (CSS) and psoriatic arthritis (PA). Researched group was presenting by 46 women (mean age 51 years; range 18-73) and 10 men (mean age 50 years; range 27-78). Depressive symptoms were assessed using the Beck Depression Inventory (BDI) and Hamilton Depression Scale (HAM-D). Peripheral blood samples were obtained from all 56 patients for standard blood cell counts. Statistical analysis was performed using Statistica 9.0 pl (Statsoft, Cracov, Poland). Spearman's rank correlation coefficient was used to estimate associations between variables. P-values < 0.05 were considered statistically significant.
The mean BDI value was found to be 12 +/- 8 and the mean HAM-D 14 +/- 9. Monocytes ratio significantly correlated with the intensity of depressive symptoms.
Stress and pain increase with illness progression are only fragments of the analyzed problem ground. Although monocytes value remained within the upper limit of normal value, their correlation with depressive symptoms suggests that the serious reason for such a depressive mood state is a high level of monocytes. It indicates on necessity of early diagnosis and treatment of depression associate with chronic proinflammatory diseases. It may be also speculated potential efficiency of an adjunctive treatment with cytokine inhibitors and oxidative stress inhibitory factors in the therapy of depressive disorders.