Mao-Hsiu Hua1, Mu-Hong Chen2, Ju-Wei Hsu3, Kai-Lin Huang3, Shih-Jen Tsai3, Cheng-Ta Li3, Ya-Mei Bai4. 1. Department of Psychiatry, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Hospital and Health Care Administration, National Yang-Ming University, Taipei, Taiwan; Department of Psychiatry, Cheng Hsin General Hospital; Department of Psychiatry, Chang Gung Memorial Hospital, Linkou Branch, Taoyuan, Taiwan. 2. Department of Psychiatry, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Psychiatry, College of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Hospital and Health Care Administration, National Yang-Ming University, Taipei, Taiwan; Department of Psychiatry, Cheng Hsin General Hospital. Electronic address: kremer7119@gmail.com. 3. Department of Psychiatry, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Psychiatry, College of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Hospital and Health Care Administration, National Yang-Ming University, Taipei, Taiwan; Department of Psychiatry, Cheng Hsin General Hospital. 4. Department of Psychiatry, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Psychiatry, College of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Hospital and Health Care Administration, National Yang-Ming University, Taipei, Taiwan; Department of Psychiatry, Cheng Hsin General Hospital. Electronic address: ymbi@mail2000.com.tw.
Abstract
BACKGROUND: Euthymic patients with bipolar disorder reportedly demonstrated increased levels of proinflammatory cytokines and cognitive function deficits. Because uncertain differences exist in cognitive function and proinflammatory cytokines between remitted bipolar I (BD1) and bipolar II (BD2) disorders, we performed this study to further investigate these differences. METHOD: We enrolled 58 patients with remitted BD1 and 27 with remitted BD2, and matched them for age and sex with 51 controls. Proinflammatory cytokines, including soluble interleukin-6 receptor (sIL-6R), C-reactive protein, and soluble tumor necrosis factor receptor 1 (sTNFR1) were measured, and performance in the Word List Memory Task (WLMT) and Wisconsin Card Sorting Task (WCST) was assessed. RESULTS: Significantly elevated levels of sTNFR1 were observed among patients with BD1 (p < .001) and BD2 (p = .038) compared with the controls; however, they did not differ between patients with BD1 and BD2 (p =.130). Working memory deficit measured by the WLMT was significantly greater in patients with BD1 (p < .001) and BD2 (p < .05) compared with controls, but did not differ between patients with BD1 and BD2 (p > 0.1). Furthermore, sTNFR1 levels were negatively correlated with cognitive function measured using the WLMT and WCST (all p < .05). DISCUSSION: Our results showed that euthymic patients with BD1 and BD2 showed similar levels of sTNFR1 and cognitive function (especially working memory) impairments. Further investigation is required to explore whether a common pathophysiology may contribute to the shared inflammatory and cognitive alterations between BD1 and BD2.
BACKGROUND: Euthymic patients with bipolar disorder reportedly demonstrated increased levels of proinflammatory cytokines and cognitive function deficits. Because uncertain differences exist in cognitive function and proinflammatory cytokines between remitted bipolar I (BD1) and bipolar II (BD2) disorders, we performed this study to further investigate these differences. METHOD: We enrolled 58 patients with remitted BD1 and 27 with remitted BD2, and matched them for age and sex with 51 controls. Proinflammatory cytokines, including soluble interleukin-6 receptor (sIL-6R), C-reactive protein, and soluble tumor necrosis factor receptor 1 (sTNFR1) were measured, and performance in the Word List Memory Task (WLMT) and Wisconsin Card Sorting Task (WCST) was assessed. RESULTS: Significantly elevated levels of sTNFR1 were observed among patients with BD1 (p < .001) and BD2 (p = .038) compared with the controls; however, they did not differ between patients with BD1 and BD2 (p =.130). Working memory deficit measured by the WLMT was significantly greater in patients with BD1 (p < .001) and BD2 (p < .05) compared with controls, but did not differ between patients with BD1 and BD2 (p > 0.1). Furthermore, sTNFR1 levels were negatively correlated with cognitive function measured using the WLMT and WCST (all p < .05). DISCUSSION: Our results showed that euthymic patients with BD1 and BD2 showed similar levels of sTNFR1 and cognitive function (especially working memory) impairments. Further investigation is required to explore whether a common pathophysiology may contribute to the shared inflammatory and cognitive alterations between BD1 and BD2.