TNF-α -308G/A and IL-8 -251T/A were significantly associated with AD and IL-1β +3953C/T with late-life depression, while the significance of these associations was lost after Bonferroni correction.
In this study, we tested the leukocyte mRNA expression levels of genes belonging to glucocorticoid receptor (GR) function (FKBP-4, FKBP-5, and GR), inflammation (interleukin (IL)-1α, IL-1β, IL-4, IL-6, IL-7, IL-8, IL-10, macrophage inhibiting factor (MIF), and tumor necrosis factor (TNF)-α), and neuroplasticity (brain-derived neurotrophic factor (BDNF), p11 and VGF), in healthy controls (n=34) and depressed patients (n=74), before and after 8 weeks of treatment with escitalopram or nortriptyline, as part of the Genome-based Therapeutic Drugs for Depression study.
The associations between physical disorders and incident depression were significant in the presence of 2 alleles related to higher proinflammatory cytokine production (tumor necrosis factor-α -850T and IL-8 -251A), and 1 allele related to lower anti-inflammatory cytokine production (IL-4 +33C).
Logistic regression analyses showed that after controlling for epidemiologic (age and sex), clinical (stage of disease, comorbidities), and symptom (depressed mood and fatigue) variables known to influence pain severity, variant alleles in IL-8 -251T/A [odds ratio (OR), 2.35; 95% confidence interval (95% CI), 1.10-5.03; P = 0.03] persisted as a significant factor for severe pain for White patients.