Glycemic Targets
Glycemic Targets in the Hospital: an Evolving Science
Glycemic Targets
Data have continued to evolve around the issue of hyperglycemia in hospitalized patients. One thing remains clear—hyperglycemia in the hospital setting, whether in critically ill patients or those not critically ill—is associated with worse outcomes, both in patients with a previous diagnosis of diabetes or those with newly recognized glucose abnormalities. The data continue to support that uncontrolled hyperglycemia is unacceptable. What has remained more challenging is how to safely and effectively control hyperglycemia and to what levels.
Based on impressive findings from a European study of critically ill patients treated with intravenous insulin to treatment goals of 110 mg/dL,1 which showed improvements in various parameters of serious morbidities, as well as improvements in mortality, treatment goals for critically ill patients were developed in 2004.2
Since then, more experience and more data have emerged from clinical trials across many more patients and many more countries. Although hyperglycemia is associated with adverse patient outcomes, interventions to normalize glycemia have yielded inconsistent results. Recent trials in critically ill patients have failed to show a significant improvement in mortality with intensive glycemic control3,4 or have even shown increased mortality risk.5 Moreover, these recent RCTs have highlighted the risk of severe hypoglycemia resulting from such efforts.3-8
A critical review of these data has led AACE and ADA to jointly recommend more conservative targets of 140-180 mg/dL in the ICU setting. Greater benefit may be realized at the lower end of this range. Although strong evidence is lacking, somewhat lower glucose targets may be appropriate in selected patients. Targets less than 110 mg/dL, however, are not recommended. The use of intravenous insulin infusions in the intensive care setting is recommended to control hyperglycemia.9
Targets for most patients admitted to general medical-surgical wards are between 140-180 mg/dL. In noncritically ill patients who have diabetes and who have been treated successfully to lower targets in the outpatient setting, lower targets may also be acceptable. The use of regularly scheduled subcutaneous insulin injections is the most common method used to control hyperglycemia in the noncritically ill setting.9
Hospitalized patients represent a dynamic patient population. It is highly likely that the management of inpatient hyperglycemia will continue to evolve with more experience, more research, and greater understanding of the pathophysiology of hyperglycemia in different patient populations.
References:
1. Van den Berghe, Wouters P, Weekers F, et al. Intensive insulin therapy in the critically ill patients. N Engl J Med. 2001;345:1359-1357.
2. American College of Endocrinology Task Force on Inpatient Diabetes Metabolic Control: American College of Endocrinology position statement on inpatient diabetes and metabolic control. Endocr Pract. 2004;10(suppl 2):4-9.
3. Wiener RS, Wiener DC, Larson RJ. Benefits and risks of tight glucose control in critically ill adults: a meta-analysis [published correction appears in JAMA. 2008;301:936]. JAMA. 2008;300:933-944.
4. Brunkhorst FM, Engel C, Bloos F, et al (German Competence Network Sepsis [SepNet]). Intensive insulin therapy and pentastarch resuscitation in severe sepsis. N Engl J Med. 2008;358:125-139.
5. Finfer S, Chittock DR, Su SY, et al (NICE-SUGAR Study Investigators). Intensive versus conventional glucose control in critically ill patients. N Engl J Med. 2009;360:1283-1297.
6. Krinsley JS, Grover A. Severe hypoglycemia in critically ill patients: risk factors and outcomes. Crit Care Med. 2007;35:2262-2267.
7. Van den Berghe G, Wilmer A, Hermans G, et al. Intensive insulin therapy in the medical ICU. N Engl J Med. 2006;354:449-461.
8. Griesdale DE, de Souza RJ, van Dam RM, et al. Intensive insulin therapy and mortality among critically ill patients: a meta-analysis including NICE-SUGAR study data [published online ahead of print March 24, 2009]. CMAJ. doi:10.1503/cmaj.090206.
9. Moghissi ES, Korytkowski MT, DiNardo M; American Association of Clinical Endocrinologists; American Diabetes Association. American Association of Clinical Endocrinologists and American Diabetes Association consensus statement on inpatient glycemic control. Endocr Pract. 2009;15:353-369.
