Background: Short-term, transient hyperglycemia is associated with
adverse outcomes in acutely ill populations. Because parenteral nutrition (PN)
is dextrose based, we hypothesized that exposure to PN would be associated
with hyperglycemia and that greater levels of dextrose infusion would be
associated with higher glucose concentrations. Our objective was to examine
the temporality, incidence, and dose response from dextrose load upon
hyperglycemia using several serum glucose cut points in PN vs non-PN
HSCT recipients. Methods: The medical records of adults admitted for
initial autologous or allogeneic hematopoietic stem cell transplant (HSCT) at
2 university-affiliated hospitals between September 1999 and December 2003
were used in this retrospective cohort. To minimize the impact of disease
acuity on serum glucose, patients with diabetes mellitus, steroid
administration, patients with recently treated infections, or patients who
died during therapy were eliminated from the study. Serum glucose values were
recorded once per day from the first morning venous blood draw (2
am–6am) to achieve uniformity among patients, to
avoid measurements occurring more frequently among hyperglycemic patients, and
to minimize the influence of oral intake. Hyperglycemia was examined using
several serum glucose cut points (110, 125, 150, 175, and 200 mg/dL). Wilcoxon
rank-sum tests were used to detect differences in hyperglycemic events between
PN and non-PN subjects, and mixed-effects regression models were used to
detect the association between PN exposure and hyperglycemia. To address the
temporality and incidence of hyperglycemia between PN vs non-PN
participants, before and “after” time frames were created.
Preinfusion (before) and actual infusion (after) times were used for these
intervals for PN patients; however, the average hospital days before (before)
or during (after) PN infusion were used for comparison in non-PN recipients
(ie, autologous non-PN before = hospital days 1–10, after = hospital
days 11–21). Results: Of the 208 patients who qualified for
inclusion 49% (n = 101/208) received PN, which provided on average 26 kcal per
kg, 1.3 g of protein per kg, and 2.7 mg/kg/min of dextrose (range
1.3–3.9 mg/kg/min). The proportion of hyperglycemic days before was not
different between groups; however, it was significantly greater after in PN
vs non-PN patients, regardless of serum glucose cut point. A dose
response between dextrose administered (mg/kg/min) and serum glucose
concentrations was not seen. When longitudinally presented, the temporal
relationship between serum glucose and PN initiation was reflected
approximately on hospital day 9. Using regression models that account for
repeated measures, the odds of having hyperglycemia (yes/no; glucose >110
mg/dL) after PN exposure were nearly 4 times (odds ratio 3.9; 95% confidence
interval, 2.7–5.5) that of non-PN exposed, after controlling for donor
type, race, age, and conditioning chemotherapy. PN was the only variable to
significantly interact with time (p < .0001), signifying not only
the change in odds over time but also as powerful evidence that PN was the
causative agent of hyperglycemic events. Conclusions: The broad use
of PN at levels within current clinical guidelines in HSCT adults was
associated with profound hyperglycemia; however, greater dextrose dose, within
the narrow levels administered in this cohort, was not associated with higher
glucose concentrations.
Hyperglycemia has been demonstrated to cause untoward effects in hospitalized patients. This paper examines the impact of centrally administered parenteral nutrition on the temporality, incidence and dose response of hyperglycemia using several blood glucose cut-points in adult bone marrow transplant patients.