This is a very interesting single-center prospective cohort study demonstrating that appropriate timing of intensive insulin therapy (IIT) has a major effect on patient morbidity, mortality, length of stay in the ICU and in the hospital, so clinicians should focus on early control of hyperglycemia.

A total of 178 patients were given IIT either within the first 48h after ICU admission or thereafter. The early-IIT group had more ventilator-free days, shorter ICU and hospital stays, and lower ICU and hospital mortality. Nearly 80% of patients investigated in both groups suffered from sepsis or acute respiratory failure. Both conditions are associated with an exaggerated systemic inflammatory response, usually resulting in peak cytokine levels within the first 48-72 hours. During this very early phase of disease, major pathophysiologic alterations occur in cell metabolism, including substrate utilisation and mitochondrial function, which most likely affect subsequent outcome. Experimental and some clinical studies suggest that IIT and/or early restoration of normoglycemia not only attenuate the magnitude of the inflammatory response to infection or trauma but also beneficially influence cell metabolism. Therefore, appropriate timing, e.g. starting IIT at the early stages of critical illness, may be of utmost importance regarding effectiveness of IIT.

Of course, this study has major limitations because of the relatively small number of patients included and its observational character. However, combined with knowledge mostly coming from animal experiments and pathophysiological reasoning, the results are sound.