HIGHER LEVELS OF INTERLEUKIN-6 AND TUMOR NECROSIS FACTOR-ALPHA ARE ASSOCIATED WITH SUICIDAL IDEATION IN ADOLESCENTS (NEURO4)
Giana Isabella Teresi, Stanford University, Stanford, CA, United States (Primary Presenter)
Rachel Lindsey Weisenburger, Stanford University, Stanford, United States (Co-First Author)
Johanna Christina Walker, Stanford University, Stanford, United States
Jillian Rose Segarra, Stanford University, Stanford, United States
Yael Rosenberg-Hasson, Stanford University, Stanford, United States
Holden Maecker, Stanford University, Stanford, United States
Ian Gotlib, Stanford University, Stanford, United States
Tiffany Ho, University of California, San Francisco, San Francisco, United States
Background: Suicidal ideation (SI), a major risk factor for subsequent suicidal-related behaviors and attempts, often onsets during adolescence (ages 13-18). Although studies have shown that pro-inflammatory cytokines are associated with SI in adults with depression, less is known about biological markers of SI in adolescents. Here we examined the association between pro-inflammatory cytokines and current SI in a sample of depressed adolescents and healthy controls.
Methods: 38 adolescents meeting threshold or subthreshold criteria for a DSM-IV depressive disorder and 20 healthy controls (41 female, 16.26±1.21 years) gave a dried blood spot (DBS) sample from which we extracted median fluorescence intensity values for Interleukin-6 (IL-6) and Tumor Necrosis Factor (TNF-ɑ). Participants also completed the Suicidal Ideation Questionnaire (SIQ-JR) and Reynolds Adolescent Depression Scale (RADS-2). We conducted negative binomial regressions covarying for age, sex, BMI, RADS-2 t-scores, and corticosteroid medication use.
Results: In the full sample, higher SIQ scores were associated with higher levels of both IL-6 (p=0.018) and TNF-ɑ (p<0.001); in the depressed subsample SIQ scores were associated with TNF-ɑ (p=0.025) but not with IL-6 (p=0.176).
Discussion: We found that peripheral inflammation is positively associated with levels of SI reported in the past month in adolescents with and without depression. Given the scalability of DBS protocols, these findings could contribute to the identification of risk and treatment targets. Results should be replicated in larger samples, and longitudinal research should examine the causal nature of the relation between inflammation and SI.