Endocrinology & Diabetology
Diabetes is a chronic metabolic disorder characterised by hyperglycaemia, the presence of high sugar (glucose) levels in the blood. The level of glucose in the blood is regulated by insulin hormone. The normal level of glucose in the blood should be between 70 and 100 mg/dL (fasting) and <140 mg/dL (random). (There are different views about the normal range of blood glucose. Please discuss the same with your healthcare team.) Impaired production or function of insulin increases glucose levels in the blood.
There are 3 types of diabetes:
- Type 1 diabetes is an autoimmune disease, in which the insulin producing cells are mistakenly killed by the body's defence system; hence, decreasing the production of insulin and increasing the accumulation of blood sugar.
- Type 2 diabetes occurs either due to the reduced production of insulin or the inadequate use of the hormone produced by the various cells of the body. This is termed as insulin insensitivity and is the most common type of diabetes.
- Gestational diabetes is a temporary condition, which occurs during pregnancy. Gestational diabetes resolves after child birth, but poses a future risk for the development of type 2 diabetes in the mother.
The pancreas is situated just below the stomach and produces enzymes for the digestion of food, and the hormones insulin and glucagon for the regulation of blood glucose. The pancreas consists of a group of cells called the islets of Langerhans, which produce and store the hormone. Carbohydrates in the food we eat are broken down to form glucose, which is either used immediately by the muscles and liver as energy or stored for later use. When levels of blood sugar start rising after a meal, the islets of Langerhans secrete insulin, which transports sugar to the cells. If the pancreas fails to produce sufficient amounts of insulin or the body's cells are insensitive to the hormone, glucose starts accumulating in the blood stream, leading to diabetes.
The various causes of diabetes include:
- Sedentary lifestyle
- Viral infection or nutritional factor in childhood
- Old age
- High blood triglyceride levels
- Autoimmunity, when the body's defence system attacks and destroys pancreatic cells
Diabetes causes damage to the cardiovascular system, vision, kidneys, nerves, feet, hearing, skin and blood vessels. Gestational diabetes can lead to complications such as high birth weight, requiring C-section delivery, and preeclampsia or high blood pressure that could be life-threatening for both mother and child.
The common symptoms of diabetes mellitus are increased thirst, frequent urination, extreme hunger, unexplained weight loss, fatigue, blurred vision, delayed wound healing, dehydration, altered mental status and frequent infections.
Stages of diabetes are decided based on blood glucose levels. If your blood glucose levels are between 108 and 126 mg/dL (fasting) and 141 to 200 mg/dL (random) then you are considered to be in the pre-diabetic stage. At this stage, although the blood sugar level is high it cannot be classified as diabetes and the sugar levels can be controlled by weight loss and exercise. Blood glucose levels >126 mg/dL (fasting) and ≥200 mg/dL (random) is considered a diabetic stage and will require medication to keep your blood sugar levels under control. The development of type 2 diabetes at a young age increases the risk of diabetes progressing into complications such as neuropathy.
When you present to your doctor with the above symptoms, your doctor will order a few tests to diagnose diabetes:
- Fasting blood glucose test: The fasting blood glucose test is the preferred test for diagnosing diabetes. A sample of blood is drawn after fasting overnight and tested for levels of glucose. Levels of 100 to 125 mg/dL is inferred as prediabetes, while levels more than 125 mg/dL on two or more separate tests on different days indicates diabetes.
- Random blood glucose test: A blood sample is taken randomly, at any time of day (regardless of whether you have eaten or not). Blood glucose levels of 200 mg/dL or higher indicates diabetes.
- Oral glucose tolerance test: It is commonly performed for diagnosing gestational diabetes, diabetes and pre-diabetes. In this test, a sample of blood is taken to determine fasting blood sugar level. Following this, a standard amount of sugar is provided orally and blood samples are taken at specific intervals within 2 hours to measure the blood glucose. Levels more than 200 mg/dL indicates diabetes, and levels 140 to 199 mg/dL indicates prediabetes.
When left untreated, diabetes can damage various parts of the body:
- Eyes: Diabetic retinopathy, cataracts and glaucoma
- Kidney: diabetic nephropathy, progressive renal failure
- Nerves: diabetic neuropathy and erectile dysfunction
- Cardiovascular diseases: Early coronary artery disease, peripheral vascular disease, hypertension and ischemia
- Feet: Increased risk of infections and foot ulcers
- Slow wound healing, many times necessitating amputation
The Treatment Options
Treatment of diabetes involves diet, exercise, medications and other lifestyle improvements. These will help to maintain normal blood sugar levels, and prevent or minimise complications of diabetes.
- Diet: Eat a consistent well balanced diet that is high in fibre, and low in saturated fats and concentrated sweets. Meals should be taken on a regular schedule and long periods between eating should be avoided.
- Exercise: Regular exercise in any form can help maintain a healthy weight and blood sugar levels within the normal range.
- Smoking and alcohol use: Stop smoking and limit consumption of alcohol.
- Medical treatment: Medicines are prescribed based on the type of diabetes, presence of associated medical problems, complications of diabetes, age and general health. The treatment usually involves daily injection of a combination of insulin. It is given in two or three injections per day, generally around meal times. There are other drugs that can be taken orally.
- Treating comorbidities: Your doctor will also include medications and treatments to prevent, control and treat other associated conditions.
Regular monitoring of blood glucose is necessary to prevent long-term complications of the disease.
Some other treatments that are suggested to control diabetes include:
- Pancreatic transplantation: This method can be indicated for type 1 diabetes. If the pancreas transplant is successful, you would no longer require insulin. However, the treatment may have major side effects like organ rejection, which can be more fatal than diabetes itself. Hence, this treatment is suggested only in severe cases where diabetes cannot be controlled through any other means.
- Bariatric surgery: This is a weight loss surgery. Though it is not a direct treatment for diabetes, weight loss surgeries may help to reduce blood sugar in patients with a BMI of 35 and above.