A study with a small sample size (n = 142), including adult patients of all ages with sepsis or SIRS (median age [range], sepsis vs. SIRS, 75 [42–98] vs. 68 [37–81] years), suggested that increased serum IL-6 levels were associated with an increased risk of 28-day mortality (HR = 1 pg/mL change, 1.0004) [7]. This evidence concerns the gene IL6 and systemic inflammatory response syndrome.