Objective: The aim of this study was to determine the prevalence of steatorrhea in patients with Graves' disease and to assess its significance and correlation with changes in body mass index (BMI), coefficient of fat absorption (COFA), and pancreatic exocrine function in these patients.
Methods: Daily dietary fat intake, 24 h fecal fat, COFA, fecal chymotrypsin activity (as an index of pancreatic exocrine function), and total T3, T4, and TSH levels were assessed in 28 patients with active Graves' disease. In 24 patients, reassessment was done after attaining a euthyroid state with carbimazole therapy.
Results: In the thyrotoxic state, 13 of 28 patients had steatorrhea, whereas 15 had normal (<6 g/day) fat excretion (11.4 +/- 6.7 g vs 2.9 +/- 0.8 g, p = 0.0007). Daily fat intake, basal BMI, and serum T3 and T4 levels were similar in the steatorrheic and nonsteatorrheic groups. The mean COFA of the steatorrheic group was significantly lower than that of nonsteatorrheic group (91.6% +/- 4.8% vs 97.7% +/- 0.9%, respectively; p = 0.0006). In the steatorrheic group, fat excretion and COFA normalized after attainment of euthyroidism (changes in fat excretion and COFA = 7.3% +/- 6.3 g/day and 7.7% +/- 5.4%, respectively). Fecal chymotrypsin levels were similar in the steatorrheic and nonsteatorrheic thyrotoxics and in 16 healthy control subjects. The levels did not show any significant changes following attainment of euthyroid status.
Conclusion: Steatorrhea associated with a decrease in COFA can occur in a reversible manner in 46% of patients with Graves' disease. However, steatorrhea in these patients is not linked with weight loss or with pancreatic exocrine dysfunction.