CHICAGO – Hyperglycemia is common in patients receiving enteral nutrition and is a significant risk factor for hospital mortality, according to a retrospective study involving 157 patients.
Nearly 60% of patients had capillary blood glucose (CBG) values that exceeded 140 mg/dL, and nearly one-third exceeded 180 mg/dL.
More important, almost 40% of patients had a mean CBG of more than 180 mg/dL for the entire duration of their tube feedings.
At the threshold glucose of 180 mg/dL or more, the odds of dying in the hospital during tube feeding are approximately three times higher than for patients who had better glycemic control, Dr. Michael Jakoby said at the annual scientific sessions of the American Diabetes Association.
Patrice Wendling/IMNG Medical Media
Dr. Michael Jakoby
"We look at this body of work as just a stepping point to the next logical extension, which is to investigate ways that we can improve glycemic control for patients receiving any artificial nutrition, whether it’s parenteral or enteral," said Dr. Jakoby, chief of endocrinology at St. John’s Hospital in Springfield, Ill.
He previously reported that using an insulin protocol that determined insulin doses based on carbohydrate delivery and CBG was superior to ad hoc insulin dosing in the management of parenteral nutrition–induced hyperglycemia (JPEN J. Parenter. Enteral. Nutr. 2012;36:183-8).
Malnutrition among nonsurgical patients is high, and more than 40% of general surgery service patients have been reported to be malnourished (Am. J. Clin. Nutr. 1997;66:1232-9). Five studies since 2005 have established a link between parenteral nutrition and increased morbidity and in-hospital mortality, but little is available on outcomes with enteral nutrition, Dr. Jakoby explained.
The current analysis involved 157 patients receiving enteral nutrition in 2011 at St. John’s, a 350-bed hospital where each year an estimated 11,000 patients receive artificial nutrition for 2 weeks.
Of those patients, 58 were diagnosed with hyperglycemia (37%), defined as a mean CBG of 180 mg/dL or more for the duration of tube feedings.
Hyperglycemic patients were significantly older than controls (75 vs. 67), twice as likely to have a preexisting diagnosis of diabetes (81% vs. 41%), had 2 fewer days of enteral nutrition (7 vs. 9), and were less likely to be in the ICU during their tube feedings (62% vs. 83%), he said.
The two groups were well matched with regard to the amount of protein, fat, and total energy they received; however, hyperglycemic patients received significantly fewer carbohydrates than did controls (2.2 g/kg per day vs. 2.7 g/kg per day).
"With the documentation available to us, it seemed that this was an adaptive response to help combat the hyperglycemia that was happening during pure enteral nutrition," Dr. Jakoby said.
Cardiac complications – a composite of myocardial infarction, arrhythmia, and cardiac arrest – were increased in hyperglycemic patients (34% vs. 22%), but this difference was not significant in univariate analysis (odds ratio, 1.84; P = .13).
The risk of hospital mortality, however, was significantly higher in hyperglycemic patients in univariate analysis (36% vs. 16%; OR, 2.94), and remained significant in multivariate analysis after adjustment for age, sex, and preexisting diagnosis of diabetes (OR, 3.28), he noted.
During a discussion of the results, Dr. Jakoby said analyses are forthcoming looking at the impact of glycemic variability during hospitalization, observing that in a prior study he conducted, glycemic variability in the noncritical care setting strongly correlated with hospital stay and a greater likelihood of going from hospital to nursing home or the morgue.
Dr. Jakoby reported serving as a speaker for Sanofi-Aventis, Merck, and Novo Nordisk.