The blood sugar level is the amount of glucose (sugar) in the blood. It is also known as serum glucose level. It is expressed as milligram per decilitre (mg/dl).
Normally, blood glucose levels stay within narrow limits throughout the day 70-150mg/dl. But they are higher after meals and usually lowest in the morning.
In diabetes the blood sugar level moves outside these limits until treated. Even with good control of diabetes, the blood sugar level will still at times drift outside this normal range.
DM is a chronic disorder requiring lifelong modifications in lifestyle and medication. Although this is an inconvenience to the patients, the availability of new forms of treatment associated with a reduction in complications provide hope that they can lead a healthy and normal life.
According to the WHO, by 2030 there will be 366 million diabetic subjects worldwide.
Worldwide, 3.2 million deaths are attributable to diabetes every year.
One in 20 deaths is attributable to diabetes; 8,700 deaths every day; six deaths every minute.
At least one in ten deaths among adults between 35 and 64 years old is attributable to diabetes.
Three-quarters of the deaths among people with diabetes aged under 35 years are due to their condition.
Approximately 16 million people in the United States and 2.2 million in UK (another million may be undiagnosed; Poole 1989), have diabetes mellitus, a group of diseases that affects the body's ability to effectively use simple sugars from digested foods and produce energy.
Globally DM = 2.8%.
Detecting diabetes as early as possible helps to control the disease and protect against additional serious health complications.
What is happening in case of diabetes?
In diabetic patients, the pancreas is either produces little or no insulin, or the body's cells do not respond to the insulin that is produced (insulin resistance).
Glucose builds up in the blood, overflows into the urine and passes out of the body, with the result that the body loses its main source of fuel and a diabetic case could be established.
Diabetes mellitus (DM) is characterized by chronic hyperglycemia and affects metabolism of carbohydrates, protein and fats.
What is Diabetes?
DM is a metabolic disorder of multiple aetiology characterized by chronic hyperglycaemia with disturbances of carbohydrate, fat, and protein metabolism resulting from defects of insulin secretion, insulin action, or a combination of both.
In type 1 diabetes, it is due to a virtually complete lack of endogenous pancreatic insulin production, whereas in type 2 diabetes, the rising blood glucose results from a combination ofgenetic predisposition, unhealthy diet, physical inactivity, and increasing weight with a central distribution resulting in complex pathophysiological processes.
Traditionally, diagnosis of diabetes was based on symptoms due to hyperglycaemia, but during the last decades much emphasis has been placed on the need to identify diabetes and other forms of glucose abnormalities in asymptomatic subjects.
DM is associated with development of specific long-term organ damage (diabetes complications) including; retinopathy with potential blindness; nephropathy with a risk of progression to renal failure; neuropathy with risk for foot ulcers, amputation, and autonomic dysfunction (e.g. sexual impairment).
Patients with diabetes are at a particularly high risk for cardiovascular, cerebrovascular, andperipheral artery disease.
Classification of diabetes
Four main aetiological categories of diabetes have been identified as
a) Diabetes type 1
b) Diabetes type 2
c) Pre-diabetes (Impaired Glucose Homeostasis)
d) gestational diabetes
e) other specific types
a) Diabetes type 1,
Type 1 diabetes characterized by deficiency of insulin due to destructive lesions of pancreatic B-cells; usually progresses to the stage of absolute insulin deficiency.
Typically, it occurs in young subjects with acute-onset with typical symptoms of diabetes together with weight loss and propensity to ketosis, but type 1 diabetes may occur at any age, sometimes with slow progression.
People who have antibodies to pancreatic B-cells such as glutamic-acid-decarboxylase (GAD), are likely to develop either typical acute-onset or slow-progressive insulin-dependent diabetes.
Today antibodies to pancreatic B-cells are considered as a marker of type 1 diabetes (though not detectable in all patients)
b) Diabetes type 2,
Type 2 diabetes is caused by a combination of decreased insulin secretion and decreased insulin sensitivity. Typically, the early stage of type 2 diabetes is characterized by insulin resistance and decreased ability for insulin secretion causing excessive postprandial hyperglycaemia. This is followed by a gradually deteriorating first-phase insulin response to increased blood glucose concentrations.
Type 2 diabetes, comprising over 90% of adults with diabetes, typically develops after middle age. The patients are often obese or have been obese in the past and have typically been physically inactive.
Ketoacidosis is uncommon, but may occur in the presence of severe infection or severe stress.
c) Prediabetes (Impaired Glucose Homeostasis)
Two forms; may have either or both
Impaired fasting glucose (IFG): fasting plasma glucose(FPG) above normal
Impaired glucose tolerance (IGT): plasma glucose elevated after 75 g glucose load
d) Gestational diabetes
Gestational diabetes mellitus (GDM) constitutes any glucose disruption that develops during pregnancy (7%) and disappears after delivery.
Long-term follow-up studies (10 years), reveal that most (~70%), but not all, women with gestational diabetes do progress to diabetes after pregnancy.
e) Other types include:
diabetes related to specific single genetic mutations that may lead to rare forms of diabetes, as for instance MODY;
diabetes secondary to other pathological conditions or diseases (as a result of pancreatitis, trauma, or surgery of pancreas);
drug or chemically induced diabetes.
What are the symptoms of diabetes?
Methods of Diagnosis
Fasting plasma glucose (FPG)
Casual plasma glucose (any time of day)
Oral glucose tolerance test (OGTT)