Hypoglycemia Increases Serum Interleukin-6 Levels in Healthy Men and Women

Abstract
OBJECTIVE—Inflammation may have a major role in the pathogenesis and prognosis of critical illness. Hyperglycemia increases levels of the inflammatory cytokine interleukin-6 (IL-6) and is associated with increased risks of morbidity and mortality. Because hypoglycemia is also associated with adverse outcomes, we tested the hypothesis that hypoglycemia increases IL-6. RESEARCH DESIGN AND METHODS—Seventeen healthy men and women participated in hypoglycemic and euglycemic-hyperinsulinemic clamp studies (target blood glucose levels 2.7 and 5.0 mmol/l, respectively), separated by 1–3 months. IL-6, ACTH, and cortisol were measured at baseline and at 45, 75, 105, and 135 min after initiation of the insulin infusion. RESULTS—IL-6, ACTH, and cortisol levels increased significantly (P < 0.0001) during hypoglycemia but not euglycemia. IL-6 increased from mean ± SEM 1.0 ± 0.2 pg/ml at baseline to 2.6 ± 0.2 pg/ml after 135 min of hypoglycemia, whereas IL-6 levels were unchanged during euglycemia. CONCLUSIONS—Hypoglycemia increases IL-6 levels in healthy individuals.