Endocrinology & Diabetes
Endocrinology is a wide range of specialty that deals with the diagnosis and treatment of endocrine or hormone-related disorders such as diabetes, thyroid disorders, polycystic ovarian syndrome (PCOS), and pituitary disorders, etc.
Diabetes mellitus
Diabetes mellitus (DM) is a condition in which blood glucose levels persistently rise to more than normal levels resulting from defects in insulin secretion, action, or both. It is a common metabolic syndrome.
What are the Causes of Diabetes?
Insulin hormone (secreted by beta cells of pancreas) regulates glucose levels in the body. When there is insulin resistance (cells becoming resistant to the action of insulin) or a decrease in insulin secretion, glucose levels increase leading to hyperglycemia, which eventually leads to diabetes mellitus.
Types of diabetes:
Diabetes is classified into type 1 and type 2 based on the underlying causes:
Type 1 diabetes: It occurs when there is decrease in insulin production due to autoimmune destruction of beta cells of the pancreas.
Type 2 diabetes: It occurs when there are sufficient levels of glucose in the body but the cells cannot utilize this insulin due to insulin resistance.
Other types of diabetes:
Prediabetes is a condition in which blood glucose levels are high, but not too high to be diagnosed as type 2 diabetes. It is considered a warning sign for type 2 diabetes and without intervention, there is a likelihood to develop into diabetes within 2 to 3 years.
Gestational diabetes is a condition in which diabetes develops during pregnancy because of hormonal changes. 30% of gestational diabetic patients may develop type 2 diabetes.
What are the Symptoms of Diabetes?
Common symptoms of diabetes include:
- Weight loss
- Excessive thirst (polydypsia)
- Increased hunger (polyphagia)
- Increased urination, often at night (polyuria)
- Extreme fatigue
- Drowsiness
- Blurred vision
- Numbness or tingling sensation in hands and feet
- Delayed wound healing
- Dry mouth
Who is at risk for diabetes?
Children and adolescents (age < 30 y) are at higher risk for type 1 diabetes. Other predisposing factors are genetic factors or family history, pancreatic disorders, and viral or bacterial infections.
Obesity is the leading risk factor of type 2 diabetes both in adults and also children. Other risk factors of type 2 diabetes are:
- Age > 45 years
- Prediabetes
- Family history
- Hormonal changes
- High blood pressure
- High cholesterol levels
- History of gestational diabetes
- Smoking
- Heavy alcohol consumption
As in case of type 2 diabetes, obesity and sedentary lifestyle are risk factors for gestational diabetes. Other risk factors include:
- Maternal age > 25 years
- Previous pregnancy with gestational diabetes
- Smoking
- History of polycystic ovarian syndrome
- Previous childbirth of > 4 kg
- Family history of diabetes
What are the Complications of Diabetes?
Diabetes progresses slowly leading to severe complications such as:
- Diabetic neuropathy: Nerve damage, especially peripheral nervous system leading to neuropathy.
- Diabetic nephropathy: Damage to the blood vessels that supply kidneys leading to kidney damage and accumulation of wastes in the blood.
- Diabetic retinopathy: Damage to the blood vessels of eye leading to sudden loss of vision.
- Heart diseases: Diabetes can cause blockage of blood vessels leading to chest pain, stroke, and heart attack.
- Foot complications: Damage in the nerves of peripheral nervous system and peripheral vascular system lead to foot ulcers or gangrene. These wounds heal slowly and sometimes may lead to amputation or loss of limb.
- Stroke: Diabetes may gradually lead to cognitive impairment or memory loss in the patients. Stroke may also occur in some patients.
- Diabetic ketoacidosis is a life-threatening complication and is considered diabetic emergency. It occurs due to uncontrolled diabetes. Lack of insulin and hyperglycemia results in high production of ketones. When these ketones appear in blood and urine, it causes acidosis leading to metabolic complications.
- Gestational diabetes can cause complications in both mother and fetus. Nephropathy, retinopathy, heart diseases, prolonged labor, risk of cesarean delivery, and pre-eclampsia are common complications seen in mothers. In fetuses, it can cause congenital abnormalities such as cardiac and neural tube defect, hypoglycemia, macrosomia (birth weight > 4kg), hypocalcemia, birth injuries, and childhood obesity.
How is Diabetes Diagnosed?
People with at least one predisposing factor should undergo screening annually as it aids in early diagnosis. Tests recommended for diagnosis of diabetes are:
Fasting plasma glucose (FPG): Blood glucose levels are measured after fasting overnight (at least 8 hours).
Random blood sugar test (RBS): Glucose levels are measured at any time during the day and there is no requirement of fasting. If blood glucose levels are > 160 mg /dL, then other tests are recommended to confirm the diagnosis.
Oral glucose tolerance test (OGTT): It helps to determine how well your body metabolizes glucose. In this test, the patient is advised to fast overnight (at least 8 hours) and a blood sample is taken. Then, a syrupy glucose solution (dose depends on the length of the test) is given to drink. After two hours, blood sample is obtained again for measuring glucose levels.
In case of gestational diabetes, blood sample is obtained two times (after the first and second hour of consumption of glucose solution).
Glycated hemoglobin (HbA1c): The glycated hemoglobin indicates amount of blood glucose attached to the hemoglobin.
Criteria for the diagnosis of diabetes:
| Diagnostic test | Prediabetes | Diabetes |
|---|---|---|
| FPG (mg/dL) | 100 to 125 | >126 |
| OGTT (mg/dL) | 140 to 199 | >>200 |
| HbA1c (%) | 5.7 to 6.4 | >6.5 |
In patients with chronic diabetes, regular screening tests helps in monitoring blood glucose levels. Kidney function tests, eye examination, foot examination, and reflexes can be examined during follow-up visits to check for complications.
How is Diabetes Treated?
Insulin therapy is the standard treatment for patients with type 1 diabetes. Patients with type 2 diabetes may also require insulin therapy depending on the complexity of their condition. Insulin is available in injection dosage form.
Oral antihypoglycemic or antidiabetic agents such as biguanides, sulfonyl ureas, and glitazones and many newer molecules help in the treatment of type 2 diabetes. These medications act either by stimulating the production of insulin from pancreas or inhibiting the breakdown of fats (to decrease glucose production).
How can I Prevent Diabetes?
Lifestyle modifications play a significant role in the prevention and management of diabetes. Lose excess weight, consume healthy diet (in particular, limit intake of high-fat diet), be physically active, undergo screening tests regularly (at least once a year), reduce stress, stop smoking, and limit alcohol consumption to reduce the risk of diabetes.
