Patients with bipolar disorder in manic state may have increased levels of proinflammatory cytokines, researchers say.

MedWire (7/15, Grasmo) reports that, according to a study published in the Journal of Affective Disorders, patients with bipolar disorder who are “in a manic state have increased levels of proinflammatory cytokines.” For the study, researchers from Brazil’s Hospital de Clinicas de Porto Alegre “compared cytokine levels examined by flow cytometry involved in th1/Th2 balance, such as tumor necrosis factor-a, interleukin (IL)-2, IL-4, IL-6, IL-10…in 61 medicated patients with bipolar I disorder and 25 healthy individuals.” The investigators “found that only IL-4 levels were increased in euthymic patients, compared with healthy controls.” In addition, “manic patients had increased levels of IL-2 (3.20 pg/ml), IL-4 (1.90 pg/ml), and IL-6 (3.30 pg/ml), compared with controls.” In fact, “mood symptoms were positively correlated with IL-6 and IL-2 levels, as were manic symptoms indicated by the Young Mania Rating Scale,” while “depressive symptoms, as indicated by the Hamilton Depression Rating Scale, were positively correlated only with IL-6.”