Diabetes mellitus and the gastrointestinal system

Abstract

Diabetes mellitus is an important health care problem worldwide, with an increasing number of patients. According to International Diabetes Federation 2021 data, approximately 537 million adults have diabetes worldwide, and the number is projected to rise significantly every decade. Diabetes mellitus can lead to chronic complications affecting different organ systems. Chronic microvascular and macrovascular complications may occur in the same patient, influencing each other's progression and the patient's life, causing morbidities and mortality. Diabetes mellitus and the gastrointestinal tract can impact each other through different mechanisms. The gut microbiota may play an essential role in the emergence of metabolic syndrome, type 2 diabetes, and chronic diabetes-related complications. Although diabetes is primarily a disease of the endocrine pancreas, it has some detrimental effects on the exocrine pancreas and digestive enzymes. Infections, functional and organic dysfunctions due to poorly controlled diabetes, coexistences of some autoimmune gastrointestinal disorders, and tumors are the other main topics to be concerned about in the gastrointestinal complications of diabetes mellitus. Besides, antidiabetic medications used in treating diabetes mellitus can also have some unfavorable effects on the gastrointestinal system. Diabetic gastroenteropathy or gastroparesis is a common complication in prolonged diabetic patients with poor glycemic control that can markedly impair the quality of life. The gastroenterological complaints in diabetes mellitus include abdominal pain, nausea, flatulence, vomiting, heartburn, constipation, diarrhea, and fecal incontinence. The type and the duration of diabetes, the success of the metabolic control, antidiabetic agents used, and accompanying diseases can affect the extent of the gastrointestinal system involvement in diabetic patients. This chapter will discuss the effect of diabetes mellitus and its treatment on the gastrointestinal system.