4 and 6.1 mmol/l) had less morbidity and lower mortality than patients treated conventionally [34]. This approach is still very controversial [35]. Interestingly, in these studies by Van den Berghe and colleagues [34,40], patients selleck who had a history of diabetes did not benefit from the tight glucose control approach [36]. Several other studies have also indicated that, although many ICU patients with newly diagnosed or stress hyperglycemia have worse outcomes than normoglycemic patients, this relation does not hold true or is less marked for patients with known diabetes [41-46]. In the recent SAPS III study, diabetes, with or without insulin treatment, was associated with a worse hospital mortality in multivariate analysis [47].

Interestingly, diabetic patients with septic shock may have a lower incidence of developing acute lung injury or acute respiratory distress syndrome[48,49].The present study has some limitations including that, as part of an observational study with a waiver of informed consent, we were unable to obtain glycosylated hemoglobin measurements and also did not have blood glucose levels to evaluate the degree of control of the diabetes before or during the ICU admission. In addition, we compared patients with a history of insulin-treated diabetes to a cohort consisting of non-diabetics and non-insulin-treated diabetics, and have no data on the numbers of non-insulin-treated diabetics in this cohort. More importantly, we did not separate patients with type 1 and type 2 diabetes because this information is difficult to define in ICU patients.

The slightly higher proportion of medical patients in the non-diabetic group could represent a confounding factor, because mortality is usually higher in medical than in surgical ICU patients. Finally, we evaluated a heterogeneous patient population but the multivariate analysis we performed adjusted for a large number of variables, which are known to influence outcome prediction.ConclusionsIn conclusion, in this general ICU population, although patients with a history of insulin-treated diabetes were more severely ill and more likely to have renal failure, Brefeldin_A insulin-treated diabetes was not associated with increased ICU or hospital mortality rates.Key messages? Patients with a history of insulin-treated diabetes are more severely ill on admission to the ICU and more likely to have or develop renal failure and to require hemodialysis than patients with no history of insulin-treated diabetes.? However, ICU and hospital mortality rates were similar in patients with and without a history of insulin-treated diabetes.