Deficient Endogenous Glucose Production During Exercise After Total Pancreatectomy/Islet Autotransplantation

Total pancreatectomy followed by intrahepatic islet autotransplantation (TP/IAT) is performed to alleviate severe, unrelenting abdominal pain caused by chronic pancreatitis, to improve quality of life, and to prevent diabetes.

To determine the cause of exercise-induced hypoglycemia that is a common complaint in TP/IAT recipients.

Participants completed 1 hour of steady-state exercise.

Hospital research unit.

We studied 14 TP/IAT recipients and 10 age- and body mass index-matched control subjects.

Peak oxygen uptake (VO2) was determined via a symptom-limited maximal cycle ergometer test. Fasted subjects then returned for a primed [6,6-2H2]-glucose infusion to measure endogenous glucose production while completing 1 hour of bicycle exercise at either 40% or 70% peak VO2.

Blood samples were obtained to measure glucose metabolism and counterregulatory hormones before, during, and after exercise.

Although the Borg Rating of Perceived Exertion did not differ between recipients and control subjects, aerobic capacity was significantly higher in controls than in recipients (40.4 ± 2.0 vs 27.2 ± 1.4 mL/kg per minute; P < 0.001). This difference resulted in workload differences between control subjects and recipients to reach steady-state exercise at 40% peak VO2 (P = 0.003). Control subjects significantly increased their endogenous glucose production from 12.0 ± 1.0 to 15.2 ± 1.0 µmol/kg per minute during moderate exercise (P = 0.01). Recipients did not increase endogenous glucose production during moderate exercise (40% peak VO2) but succeeded during heavy exercise, from 10.1 ± 0.4 to 14.8 ± 2.0 µmol/kg per minute (70% peak VO2; P = 0.001).

Failure to increase endogenous glucose production during moderate exercise may be a key contributor to the hypoglycemia TP/IAT recipients experience.