But as a) spontaneous production of IL-1β, IL-6, and TNF-α was not significantly correlated with age, neither for controls nor for PTSD subjects and b) it was positively related to PTSD symptom severity within the PTSD group, older age in the PTSD group should not have accounted for the effects reported above 2) One third of the PTSD patients took psychotropic medication. This evidence concerns the gene TNF and post-traumatic stress disorder.