Anxiety and the immune system: IL-6 and its ties to broad, but not specific anxiety symptoms

Emerging evidence supports interleukin-6 (IL-6) as particularly sensitive to anxiety-specific processes. This study examined the relationship between basal inflammation and both broad and specific self-report measures of anxiety to clarify immune correlates of anxiety-related pathology.

Adult participants (N = 137) had a finger stick to measure IL-6, tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), and c-reactive protein (CRP) collected via dried blood spots. They also completed self-report measures of general and specific dimensions of anxiety.

Results indicated a small but significant association between IL-6 and broad measures of anxiety-related symptoms (r range = .19 - 30, p range = .001 - .04). In contrast, Il-6 was not associated with any of the specific dimensions of anxiety (p range = .10 - .65). There were no significant associations between broad or specific aspects of anxiety and TNF-α, IL-10, or CRP (p range = .10 - .94).

Findings suggest that IL-6 is a robust biomarker of broad anxiety symptomology rather than specific anxiety subtypes. This pattern aligns with emerging translational work indicating that IL-6 may be more reflective of cumulative anxiety burden and chronic stress exposure. Future studies should explore longitudinal associations and contextual moderators such as comorbid depression and early life stress.