An elevated blood glucose level on hospital admission is associated with increased 30 and 60-day mortality in nondiabetic patients with heart failure.
Previous reports have shown that elevated blood glucose levels are linked to increased mortality in critically ill patients, whether they have diabetes or not. Although diabetes is a known predictor of poor outcomes in heart failure patients, say the researchers, the effect of elevated blood glucose levels in the larger group of heart failure patients without diabetes is unclear.
To investigate, Dr. Jonathan Leor, from Sheba Medical Center in Tel-Hashomer, Israel, and colleagues analyzed data from 1122 nondiabetic patients who were hospitalized for heart failure.
Patients with admission blood glucose levels in the highest tertile had an in-hospital mortality rate of 7.2%, significantly higher than the 3% and 4% rates noted among patients in the lowest and middle tertiles. In addition, for each 1 mmol/L (18-mg/dL) increase in the glucose level, in-hospital mortality rose by 31% and 60-day mortality by 12%.
The link between admission glucose levels and mortality remained significant even after excluding patients who had experienced an acute MI, the authors note.
By contrast, the blood glucose level was not predictive of mortality at 6 months or 1 year.
"Our finding calls attention to a new prognostic marker that could be used for early risk stratification and management of patients with heart failure at hospital admission," the researchers observe.
"It is possible," they conclude, "that better glucose control may improve prognosis in hyperglycemic patients with heart failure, as demonstrated in acute MI and critically ill patients."
Comment: by Dr. J.R. Conway, Canadian Centre for Research on Diabetes
We have long known that high glucose levels adversely affect prognosis in patients with acute cardiovascular events as demonstrated by the Steno-2 Trials. Current guidelines generally recommend intensive glycemic control with IV glucose in ICU settings (Peri-Op & Peri-ACS Glucose Control. Canadian Diabetes, 18(2),Summer 2005 (Editorial).
This article reinforces the need for intensive glycemic control in acutely ill and hospitalized patients in order to achieve better outcomes. Furthermore it points out that even in people with blood sugars below the diabetic range, that high normal glucose levels are associated with increased morbidity and mortality. We need to make every effort possible to see that in the acutely ill patient, glucose levels are kept at the lower end of the normal range.