TY - JOUR PY - 2023// TI - Association of interleukin-6 with suicidal ideation in veterans: a longitudinal perspective JO - Frontiers in psychiatry A1 - Sun, Shengnan A1 - Wilson, Caroline M. A1 - Alter, Sharon A1 - Ge, Yongchao A1 - Hazlett, Erin A. A1 - Goodman, Marianne A1 - Yehuda, Rachel A1 - Galfalvy, Hanga A1 - Haghighi, Fatemeh SP - e1231031 EP - e1231031 VL - 14 IS - N2 - INTRODUCTION: Studies showing associations between inflammation in suicide are typically cross-sectional. Present study investigated how cytokine levels track with suicidal ideation and severity longitudinally.

METHODS: Veterans with a diagnosis of major depressive disorder (MDD) with or without suicide attempt history (MDD/SA n = 38, MDD/NS n = 41) and non-psychiatric non-attempter controls (HC n = 33) were recruited, MDD/SA and HC groups were followed longitudinally at 3 months and 6 months. Blood plasma was collected and processed using Luminex Immunology Multiplex technology.

RESULTS: Significant differences in depression severity (BDI) and suicidal ideation severity (SSI) were observed across all groups at study entry, wherein MDD/SA group had the highest scores followed by MDD/NS and HC, respectively. Cytokines IL-1β, IL-4, TNF-α, IFN-γ, and IL-6 were examined at study entry and longitudinally, with IL6 levels differing significantly across the groups (p = 0.0123) at study entry. Significant differences in changes in cytokine levels between depressed attempters and the control group were detected for IL-6 (interaction F(1,91.77) = 5.58, p = 0.0203) and TNF-α (F(1,101.73) = 4.69, p = 0.0327). However, only depressed attempters showed a significant change, in IL-6 and TNF-α levels, decreasing over time [IL-6: b = -0.04, 95% CI = (-0.08, -0.01), p = 0.0245 and TNF-α: b = -0.02, 95% CI = (-0.04, -0.01), p = 0.0196]. Although IL-6 levels were not predictive of suicidal ideation presence [OR = 1.34, 95% CI = (0.77, 2.33), p = 0.3067], IL-6 levels were significantly associated with suicidal ideation severity (b = 0.19, p = 0.0422).

DISCUSSION: IL-6 was not associated with presence of suicidal ideation. IL-6 however, was associated with severity of ideation, suggesting that IL-6 may be useful in clinical practice, as an objective marker of heightened suicide risk.

Language: en

LA - en SN - 1664-0640 UR - http://dx.doi.org/10.3389/fpsyt.2023.1231031 ID - ref1 ER -