Diabetes Mellitus

রাজশাহী বিশ্ববিদ্যালয়

ফার্মেসী বিভাগ

বি. ফার্ম (সম্মান) পার্ট-III এর সিলেবাস অনুযায়ী প্রণিতঃ

Introduction

The diabetic population has reached the 100 million mark. Decreased physical activity, increasing obesity, stress and changing food consumption are responsible for the increasing prevalence in the past two decades. As the incidence continues to grow diabetes is being projected to be the world’s primary killer in the next 25 years.
3.2 million deaths can be attributed to diabetes each year according to a new publication released by the world health organization (WHO) and International Diabetes Federation (IDF). Updated estimates suggest that six deaths can be attributed to diabetes or related conditions somewhere in the world every minute (WHO and IDF 2004).
In most developing counties at least one in ten deaths in adults aged 35 to 64 is attributable to diabetes, and in some the figure is as high as one in five. Diabetes has become one of the major causes of premature illness and death in most countries, mainly through the increased risk of cardiovascular disease (CVD).

Definition (WHO 1999)
The term diabetes mellitus describes a metabolic disorder of multiple etiologies, characterized by chronic hyperglycemia with disturbances of carbohydrate, fat and protein metabolism resulting from defects in insulin secretion, insulin action, or both. The effects of diabetes mellitus include long term damage, dysfunction and failure of various organs.
Clinically, it is characterized by high blood glucose concentration- hyperglycemia (fasting blood glucose>7.0 mmol/l, or plasma glucose>11.1 mmol/l two hours after meal). Hyperglycemia occurs because of uncontrolled hepatic glucose output and reduced uptake of glucose by skeletal muscle with reduced glycogen synthesis. When the renal threshold for glucose reabsorption is exceeded, glucose spills over into the urine (glycosuria) and causes an osmotic diuresis (polyuria), which inturn results in dehydration, thirst and increased drinking (Polydipsia).
Diabetes mellitus may present with characteristic symptoms-
> thirst
> polyuria
> blurring of vision and
> weight loss
In its most severe forms, ketoacidosis or a non-ketonic hyperosmolar state may develop and lead to stupor coma and, in absence of effective treatment, death.
The long-term effects of diabetes mellitus
-progressive development of the specific complications of retinopathy with potential blindness
-nephropathy that may lead to renal failure
-neuropathy with risk of foot ulcers
-amputation
-charcot joints and
-features of autonomic dysfunction- sexual dysfunction.
People with diabetes are at increased risk of cardiovascular, peripheral vascular and cerebrovascular disease.
Several pathogenetic processes are involved in the development of diabetes. These include processes which destroy the beta cells of the pancreas with consequent insulin deficiency, and others that result in resistance to insulin action. The abnormalities of carbohydrate, fat and protein metabolism are due to deficient action of insulin or target tissues resulting from insensitivity or lack of insulin.
A serious complication of intensive therapy was an increased incidence of severe hypoglycemia. Patients receiving intensive therapy had a threefold greater incidence of severe hypoglycemia (blood glucose below 2.8 mmol/l and needing external resuscitative assistance) and hypoglycemic coma than did conventionally treated subjects.

Classification
The first widely accepted classification of diabetes mellitus was published by WHO in 1980 and in modified form in 1985. The 1985 classification is widely accepted and is used internationally. It includes both staging of diabetes mellitus based on clinical descriptive criteria and a complementary etiological classification.

Type 1 diabetes mellitus
Type 1 indicates the processes of beta cell destruction that may ultimately lead to diabetes mellitus in which “insulin is required for survival” to prevent the development of ketoacidosis, coma and death. Previously known as insulin-dependent DM (IDDM).

Type 2 diabetes mellitus
Type 2 is the most common form of diabetes and is characterized by disorders of insulin action and insulin secretion either of which may be the predominant feature. By definition, the specific reasons for the development of these abnormalities are not yet known. Previously known as non-insulin-dependent DM (NIDDM).

Other specific types
Other specific types are currently less common causes of diabetes mellitus, but are those in which the underlying defect of disease process can be identified in a relatively specific manner they include, for example, fibrocalculous pancreatopathy, a form of diabetes which was formerly classified as one type of malnutrition-related diabetes mellitus (MRDM).
Impaired glucose regulation --- impaired glucose tolerance (IGT) and impaired fasting glycemia (IFG)
Impaired glucose regulation (IGT and IFG) refers to a metabolic state intermediate between normal glucose homeostasis and diabetes. It should be stated unequivocally, however, that IFG and IGT are not interchangeable and represent different abnormalities of glucose regulation one is the fasting state and one post-prandial.
Gestational diabetes
Gestational diabetes is carbohydrate intolerance resulting in hyperglycemia of variable severity with onset or first recognition during pregnancy. It does not exclude the possibility that the glucose intolerance may antedate pregnancy but has been previously unrecognized. The definition applies irrespective of whether or not insulin is used for treatment or the condition persists after pregnancy.

Treatment
Studies have shown that many complications of diabetes can be prevented or delayed through effective management. This includes lifestyle measures such as a healthy diet, physical activity, the avoidance of overweight and obesity, and not smoking. Preventative care need not involve costly treatment or medication. Education in good foot care as well as regular inspection is a good example of a low cost method of prevention.
Diabetes therapy is not only about lowering glucose, but also about the overall reduction in the risk factors for diabetic complications, which includes the control of blood pressure and blood lipids.
This requires lifelong care and management. Health systems that are able to deliver optimal care need to be designed around the needs of the person with the condition, as on a day to day basis most diabetes care is undertaken by the person with diabetes and not the health professional. Diabetes education plays a key role in empowering people with the knowledge and skills to manage their own condition effectively. In order to prevent or delay complications, people with diabetes may have to modify their lifestyle.
People with type 2 diabetes often require oral drugs, and sometimes insulin to control their blood glucose levels. People with type 1 diabetes require insulin to survive. Although insulin has been designated an essential drug by WHO, it is not yet universally accessible to all those who need it in the majority of countries of the world. Continuous access to insulin remains a major problem in many developing countries especially those in sub- Saharan Africa. In some of these countries people with diabetes die because they cannot get the insulin they need to survive.