Interleukin-6, IL-1 receptor antagonist (IL-1RA), and tumor necrosis factor–alpha (TNF-alpha) activity was associated with inflammation and neurodegeneration in patients with chronic bipolar disorder, according to Sercan Karabulut, MD, of Kepez State Hospital in Antalya, Turkey, and associates.
In a study published in the Turkish Journal of Psychiatry, the investigators collected enzyme-linked immunosorbent assays from 30 patients with early-stage bipolar disorder, 77 with chronic disease, and 30 healthy controls. Early-stage disease patients were significantly younger than chronic patients (25.3 years vs. 37.8 years). reported Dr. Karabulut and associates.
Patients with chronic bipolar disorder had significantly increased levels of all measured markers, compared with those with early-stage disease and the healthy controls. IL-6 and IL-1RA levels correlated with neuron-specific enolase and S100B, biomarkers that are associated with glial alterations and neuronal damage. TNF-alpha correlated with scores on the Clinical Global Impressions Scale and other measures.
“The present findings support in part the hypothesis that inflammation starts at later stages of [bipolar disorder], presumably as an associated effect of gliosis and neuronal loss, which appear to be particularly associated with IL-1RA and IL-6 activity,” the investigators wrote. “TNF-alpha ... might be a useful prognostic marker in patients with [bipolar disorder].”
No conflicts of interest were reported.
SOURCE: Karabulut S et al. Turk Psikiyatri Derg. 2019 Winter;30(2):75-81.