Effect of early intensive insulin therapy on immune function of aged patients with severe trauma

This study examined the effect of intensive insulin therapy on immune function and inflammatory factors at the early phase after severe trauma. At day 1, 3, 5, 7 after admission, subsets of CD4(+) helper T lymphocytes (Th1/Th2) and human leukocyte antigen (HLA)-DR expression on CD14(+) monocytes were flow cytometrically measured. Levels of cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10) and other immunity markers, such as IgA, IgG, IgM, C3, C4 and C reaction protein (CRP) were examined in two groups. The results showed that TNF-α, IL-6 and CRP levels in the intensive insulin therapy group were significantly lower than those in the conventional therapy group, whereas IL-10 levels were substantially increased after intensive insulin therapy. C3 level at day 3, 5, 7 and C4 levels at day 5, 7 were lower in the intensive therapy group than in the conventional therapy group. Th1/Th2 ratios decreased gradually over time in both groups, and were much lower at day 3, 5, 7 in intensive therapy group. There were significant differences among day 3 to day 7 after admission in HLA-DR expression in CD14(+) monocytes. It was concluded that the intensive insulin therapy could decrease pro-inflammatory cytokines and increase anti-inflammatory cytokines in the elderly suffering from severe trauma, at the same time, with complement recovery being delayed. Moreover, intensive insulin therapy promoted immune suppression and, therefore, measures need be taken to address the issue.