Diabetes

Introduction

Diabetes is a disease of the endocrine system where the body is not able to maintain the blood sugar at the required level for good health and well-being. Diabetes has become a problem of great magnitude recently. It is estimated that 10-12% of the urban and 4-6% of the rural population of India are now diabetic. There is also a corresponding increase in the diabetes related complications. For example, ischaemic heart disease, diabetic retinopathy that leads to blindness, diabetic nephropathy leading to renal failure and diabetic neuropathy leading to non-healing ulcers of the foot that may result in amputations.





Cause and Pathogenesis

Diabetes is due to defects in the beta cells of the Islets of Langerhans, that is seen in the pancreas. This leads to deficient production of insulin that is responsible for maintaining the blood sugar level. There are two types of diabetes - diabetes mellitus characterised by high blood sugar level and diabetes insipidus that is associated with defects in water reabsorbtion. Diabetes Mellitus can be further subdivided into Insulin Dependent Diabetes Mellitus (IDDM) and Non-Insulin Dependent Diabetes Mellitus (NIDDM) types. The development of the disease may be caused by various factors including hereditary factors, viruses, diet, and immunological factors.





Symptoms and Signs

A large number of diabetics may remain asymptomatic for the first several years of the disease. Often, an elevated blood sugar level may be discovered during a routine examination.

Diabetes Mellitus is characterised by excessive thirst (Polydipsia), frequent urination (Polyuria), and excessive hunger (Polyphagia). Other symptoms include numbness and a tingling sensation in the extremities, generalised weakness, non-healing ulcers and sores, impotence, deterioration in vision, frequent infections and poor wound healing. Diabetics are prone to develop deposits of fat in the blood vessel walls leading to blockage of circulation and gangrene. Smoking can aggravate this problem. They are also prone to hypertension (high blood pressure), atheroclerosis and heart disease.

Complications of diabetes include ischaemic heart disease, diabetic retinopathy that leads to vision defects and is one of the leading causes of blindness. Diabetic Nephropathy leads to renal failure necessitating dialysis and renal transplantation. Diabetic Neuropathy leads to non-healing ulcers of the foot. Loss of erection and decreased sexual libido are seen in 25-30% of diabetics with over 15 years duration of the disease. Diabetes is one of the leading causes of premature heart attacks. Diabetics can have heart attacks even without any of the usual symptoms like chest pain, sweating etc., because the nerves are affected first.





Investigations and Diagnosis

Urinary analysis for glucose and ketones can be done but are usually not very reliable. The diagnosis can be done with a fasting and post-prandial blood sugar level analysis. Fasting blood sugar levels in excess of 100-120 mgs/dl and post-prandial blood sugar levels in excess of 180 mgs/dl are indicative of the need for further tests to confirm diabetes. Later the Glucose Tolerance Test (GTT) can be done to confirm the findings. Random blood sugar estimation can also be done. Estimation of serum cholesterol and sub-fractions like LDL (Low Density Lipoproteins) and VLDL (Very Low Density Lipoproteins) and Triglycerides are also essential.

At home, the diabetic can test his or her own urine sugar by using Benedict's solution. Also, digital electronic meters make it relatively easy for the diabetics to measure their blood sugar levels. Testing the level of glycosylated haemoglobin gives a good assessment of the blood sugar control over the previous 90 days or so. Specific tests to identify the complications of diabetes also have to be done. For example, tests to detect diabetic retinopathy, renal function tests to identify diabetic nephropathy, E.C.G and other cardiac tests to identify heart disease.





Treatment and Prognosis

The aim of diabetic treatment is to achieve a good control of the diabetes. The patient can be put on a diabetic diet that is low in sugar and calories. Oral anti-diabetic drugs are effective in the treatment of the disease. At times, insulin therapy is necessary to achieve the desired blood sugar levels. There are different types of insulin that are based on contents and on the duration of action. Thus, you have bovine insulins, porcine insulins and human insulins of which the human variety is considered the best for use. There are short acting insulins, intermediate acting insulins and long acting insulins. A single dose per day of the long acting insulins may be sufficient. Combinations of short, intermediate acting and long acting insulins in a pre-mixed percentage and form are available and are increasingly popular.

Adequate exercise must be done to burn up the excess calories. With proper treatment and control, a diabetic will be able to lead a normal and healthy life. Studies have conclusively demonstrated that the more effective the control of blood sugar, the better the control of diabetes and lesser the complications. Patient education forms a very important part in the management of diabetes as it is usually a combination of diet, exercise and therapy that is required to achieve good control in many patients. A small group of patients who fall under the IDDM category (upto 15% of all diabetics) need lifelong insulin for sugar control.

Prevention


The prevention of the disease mainly rests on adequate exercise and proper diet that avoids high sugar and calorie foods. The diabetics also need to visit the doctor regularly for check-up of the eyes, kidneys, heart and feet to prevent complications. Regular check-up of blood pressure and body weight will help to keep complications at bay.