Reversible lactose malabsorption and intolerance in Graves' disease

Area of Science:

• Gastroenterology
• Endocrinology
• Clinical Medicine

Background:

• Graves' disease is an autoimmune disorder leading to hyperthyroidism.
• Thyroid hormones significantly influence gastrointestinal motility and absorption.
• The effects of Graves' disease on lactose absorption and gut transit are not fully understood.

Purpose of the Study:

• To investigate lactose absorption, gastric emptying, and oral cecal transit time in patients with untreated Graves' disease.
• To assess the influence of thyroid hormone status on these parameters.
• To compare motility in patients with Graves' disease to healthy controls.

Main Methods:

• Lactose absorption, liquid gastric emptying, and oral cecal transit time were measured in 10 untreated Graves' disease patients.
• Repeat studies were conducted in 8 patients after achieving euthyroid status, and in 2 patients during hypothyroidism.
• Motility studies were also performed in 11 control subjects.

Main Results:

• Nine out of ten Graves' disease patients exhibited lactose malabsorption.
• Lactose malabsorption normalized in 3 of 7 patients upon treatment; symptoms improved in 2.
• Liquid gastric emptying and oral cecal transit time were significantly faster in untreated patients compared to controls and euthyroid patients.

Conclusions:

• Graves' disease is associated with significant lactose malabsorption and accelerated gastrointestinal transit.
• Treatment of Graves' disease can lead to normalization of lactose absorption and improved gut motility.
• Altered thyroid hormone levels in Graves' disease may directly impact intestinal motility and absorption patterns.