Objective: Inflammatory and neurotrophic cascades has been implicated in the physiopathology of affective disorders (bipolar disorder and unipolar major depression). Nevertheless, few studies have been carried out in geriatric patients to evaluate the role of these cascades in the physiopathology of late-life depression. We aim to assess serum BDNF and cytokines levels (Il-1β, TNFα, sTNFα1, sTNFα2) in antidepressant-free patients with late-life depression.
Methods: Twenty-nine patients with late-life depression and 41 elderly controls were consecutively assessed and serum BDNF and cytokines levels were measured by standard ELISA methodology.
Results: Patients with late-life depression had a significant decreased serum BDNF level (p=0.004) and a significant increase in IL-1β (p=0.04) and sTNFα1 (p=0.001). No differences were found in serum sTNFα1 and TNFα levels. Multivariate analysis showed a significant interaction between age of onset of the depressive disorder (early- vs. late-onset) and clinical characteristic (melancholic vs. non-melancholic depression) in serum BDNF (p=0.04). No interactions were observed for inflammatory cytokines.
Discussion: Late-life depression is associated with significant changes in neurotrophic and inflammatory cascades which resembles those observed in adult patients with affective disorders. These changes may be mediated by several factors including the age of onset of the depressive disorder and its clinical characteristics.