Diabetes mellitus results mainly from a deficiency or diminished effectiveness of insulin that is normally produced by the beta cells of the pancreas. It is characterised by high blood sugar, altered sugar and glucose metabolism and this affects blood vessels and causes several organ damage. Causes of diabetes can be classified according to the types of diabetes.
Although this complication is not seen in pediatric patients, it is a significant cause of morbidity and premature mortality in adults with diabetes. People with type 1 diabetes mellitus have twice the risk of fatal myocardial infarction (MI) and stroke that people unaffected with diabetes do; in women, the MI risk is 4 times greater. People with type 1 diabetes mellitus also have 4 times greater risk for atherosclerosis.
Hypoglycemia means abnormally low blood sugar (glucose). In patients with diabetes, the most common cause of low blood sugar is excessive use of insulin or other glucose-lowering medications, to lower the blood sugar level in diabetic patients in the presence of a delayed or absent meal. When low blood sugar levels occur because of too much insulin, it is called an insulin reaction. Sometimes, low blood sugar can be the result of an insufficient caloric intake or sudden excessive physical exertion.

Over recent decades, and particularly in the past five years, researchers have found dozens of genes with links to diabetes. The count stands at about 50 genes for type 1 and 38 for type 2. The numbers have risen quickly in recent years because of advances in the gene-sequencing technology used to conduct genome-wide association studies. This technique involves taking the genetic compositions of a group of people with a disease and comparing them en masse to the genomes of people who don't have the disease.
Metformin (Glucophage, Glucophage XR, Glumetza, Fortamet, Riomet) belongs to a class of drugs called biguanides. Metformin is first-line therapy for most type 2 diabetics. It works to stop the liver from making excess glucose, and has a low risk of hypoglycemia. Hypoglycemia, or very low blood sugar can cause symptoms such as sweating, nervousness, heart palpitations, weakness, intense hunger, trembling, and problems speaking. Many patients lose some weight taking metformin, which is also helpful for blood sugar control.
Jump up ^ Farmer, AJ; Perera, R; Ward, A; Heneghan, C; Oke, J; Barnett, AH; Davidson, MB; Guerci, B; Coates, V; Schwedes, U; O'Malley, S (27 February 2012). "Meta-analysis of individual patient data in randomised trials of self monitoring of blood glucose in people with non-insulin treated type 2 diabetes". The BMJ. 344: e486. doi:10.1136/bmj.e486. PMID 22371867.
The food that people eat provides the body with glucose, which is used by the cells as a source of energy. If insulin isn't available or doesn't work correctly to move glucose from the blood into cells, glucose will stay in the blood. High blood glucose levels are toxic, and cells that don't get glucose are lacking the fuel they need to function properly.
Sugar doesn't cause diabetes. But there is one way that sugar can influence whether a person gets type 2 diabetes. Consuming too much sugar (or sugary foods and drinks) can make people put on weight. Gaining too much weight leads to type 2 diabetes in some people. Of course, eating too much sugar isn't the only cause of weight gain. Weight gain from eating too much of any food can make a person's chance of getting diabetes greater.

Studies in type 1 patients have shown that in intensively treated patients, diabetic eye disease decreased by 76%, kidney disease decreased by 54%, and nerve disease decreased by 60%. More recently the EDIC trial has shown that type 1 diabetes is also associated with increased heart disease, similar to type 2 diabetes. However, the price for aggressive blood sugar control is a two to three fold increase in the incidence of abnormally low blood sugar levels (caused by the diabetes medications). For this reason, tight control of diabetes to achieve glucose levels between 70 to120 mg/dl is not recommended for children under 13 years of age, patients with severe recurrent hypoglycemia, patients unaware of their hypoglycemia, and patients with far advanced diabetes complications. To achieve optimal glucose control without an undue risk of abnormally lowering blood sugar levels, patients with type 1 diabetes must monitor their blood glucose at least four times a day and administer insulin at least three times per day. In patients with type 2 diabetes, aggressive blood sugar control has similar beneficial effects on the eyes, kidneys, nerves and blood vessels.


Diabetes mellitus (DM) is a strong predictor of cardiovascular morbidity and mortality and is associated with both micro- and macrovascular complications.1 Cardiovascular disease (CVD) causes up to 70% of all deaths in people with DM. The epidemic of DM will thus be followed by a burden of diabetes-related vascular diseases. The number of DM patients increases with aging of the population, in part because of the increasing prevalence of obesity and sedentary lifestyle. Although the mortality from coronary artery disease (CAD) in patients without DM has declined since the 1990s, the mortality in men with type 2 diabetes (T2DM) has not changed significantly.2 Moreover, DM is an independent risk factor for heart failure. Heart failure is closely related to diabetic cardiomyopathy: changes in the structure and function of the myocardium are not directly linked to CAD or hypertension. Diabetic cardiomyopathy is clinically characterized by an initial increase in left ventricular stiffness and subclinical diastolic dysfunction, gradually compromising left ventricular systolic function with loss of contractile function and progress into overt congestive heart failure. DM accounts for a significant percentage of patients with a diagnosis of heart failure in epidemiologic studies such as the Framingham Study and the UK Prospective Diabetes Study (UKPDS).2 A 1% increase in glycated hemoglobin (HbA1c) correlates to an increment of 8% in heart failure.3 The prevalence of heart failure in elderly diabetic patients is up to 30%.3
Insulin is vital to patients with type 1 diabetes - they cannot live without a source of exogenous insulin. Without insulin, patients with type 1 diabetes develop severely elevated blood sugar levels. This leads to increased urine glucose, which in turn leads to excessive loss of fluid and electrolytes in the urine. Lack of insulin also causes the inability to store fat and protein along with breakdown of existing fat and protein stores. This dysregulation, results in the process of ketosis and the release of ketones into the blood. Ketones turn the blood acidic, a condition called diabetic ketoacidosis (DKA). Symptoms of diabetic ketoacidosis include nausea, vomiting, and abdominal pain. Without prompt medical treatment, patients with diabetic ketoacidosis can rapidly go into shock, coma, and even death may result.

Type 1 diabetes mellitus is characterized by loss of the insulin-producing beta cells of the pancreatic islets, leading to insulin deficiency. This type can be further classified as immune-mediated or idiopathic. The majority of type 1 diabetes is of the immune-mediated nature, in which a T cell-mediated autoimmune attack leads to the loss of beta cells and thus insulin.[38] It causes approximately 10% of diabetes mellitus cases in North America and Europe. Most affected people are otherwise healthy and of a healthy weight when onset occurs. Sensitivity and responsiveness to insulin are usually normal, especially in the early stages. Type 1 diabetes can affect children or adults, but was traditionally termed "juvenile diabetes" because a majority of these diabetes cases were found in children.[citation needed]


Diabetes that's triggered by pregnancy is called gestational diabetes (pregnancy, to some degree, leads to insulin resistance). It is often diagnosed in middle or late pregnancy. Because high blood sugar levels in a mother are circulated through the placenta to the baby, gestational diabetes must be controlled to protect the baby's growth and development.
While many experts believe that most type 1 genes have been identified, the situation with type 2 diabetes is much different. A recent study found that the known genetic links to type 2 probably account for only about 6 percent of the genetic predisposition for that form of diabetes. This could mean either that some of the genes discovered have a bigger effect than is currently believed or that "we are still missing 94 percent of the genes," says Atul Butte, MD, PhD, an assistant professor of pediatrics at Stanford University.
Diabetes mellitus (diabetes) is a common chronic disease of abnormal carbohydrate, fat, and protein metabolism that affects an estimated 20 million people in the United States, of whom about one third are undiagnosed. There are two major forms recognized, type-1 and type-2. Both are characterized by inappropriately high blood sugar levels (hyperglycemia). In type-1 diabetes the patient can not produce the hormone insulin, while in type-2 diabetes the patient produces insulin, but it is not used properly. An estimated 90% of diabetic patients suffer from type-2 disease. The causes of diabetes are multiple and both genetic and environmental factors contribute to its development. The genetic predisposition for type-2 diabetes is very strong and numerous environmental factors such as diet, lack of exercise, and being overweight are known to also increase one’s risk for diabetes. Diabetes is a dangerous disease which affects the entire body and diabetic patients are at increased risk for heart disease, hypertension, stroke, kidney failure, blindness, neuropathy, and infection when compared to nondiabetic patients. Diabetic patients also have impaired healing when compared to healthy individuals. This is in part due to the dysfunction of certain white blood cells that fight infection.
You should expect your dentist to inquire about how you monitor your blood sugar and your current status (e.g. most recent HbA1c, medication profile). For most routine dental procedures (e.g. examinations, simple fillings, routine cleanings), no special alterations in the delivery of dental care are necessary. However, more involved procedures, such as extensive surgery or treatment of serious infection, may interfere with your normal diabetes management. For such cases, your dentist will work with your physician to ensure the most appropriate approach to care is undertaken. For example, if you need a surgical procedure that will temporarily interfere with your ability to eat, special modifications regarding your nutrition and medication dosing may be prescribed. Finally, if you notice any unusual changes in your mouth (e.g. swelling, pain, red areas) you should see your dentist as soon as possible. These changes may indicate the presence of an infection that may compromise your normal blood sugar control and lead to a worsening of your ability to fight infection. As a result, your infection could become more difficult to treat.
If you recognize any of the symptoms, contact your doctor immediately. A simple in-office test for sugar in the urine is used for diagnosis. If that test is positive, then a drop of blood from the fingertip will confirm diabetes. Every day, thousands of adults and children around the world are diagnosed, but many go undetected. Early diagnosis cannot prevent Type 1, but it can head off potentially devastating, even fatal, health concerns.
Type 1 DM is caused by autoimmune destruction of the insulin-secreting beta cells of the pancreas. The loss of these cells results in nearly complete insulin deficiency; without exogenous insulin, type 1 DM is rapidly fatal. Type 2 DM results partly from a decreased sensitivity of muscle cells to insulin-mediated glucose uptake and partly from a relative decrease in pancreatic insulin secretion.
Schedule a yearly physical exam and regular eye exams. Your regular diabetes checkups aren't meant to replace regular physicals or routine eye exams. During the physical, your doctor will look for any diabetes-related complications, as well as screen for other medical problems. Your eye care specialist will check for signs of retinal damage, cataracts and glaucoma.
Aspirin should be used as secondary prophylaxis in all diabetic people with evidence of macrovascular disease, and it should be strongly considered as primary prevention in diabetic subjects with other risk factors for macrovascular disease, such as hypertension, cigarette smoking, dyslipidemia, obesity, and albuminuria (macro or micro).228 Because of the platelet defects associated with diabetes, it is recommended that the dose of aspirin should be 300 mg per day,228–230 although the American Diabetes Association’s position statement (http://www.diabetes.org/DiabetesCare/supplement198/s45.htm) advocates a dose of 81 to 325 mg enteric-coated aspirin per day. If the patient cannot tolerate aspirin, then clopidogrel231 can be used.
The relationship between type 2 diabetes and the main modifiable risk factors (excess weight, unhealthy diet, physical inactivity and tobacco use) is similar in all regions of the world. There is growing evidence that the underlying determinants of diabetes are a reflection of the major forces driving social, economic and cultural change: globalization, urbanization, population aging, and the general health policy environment.[74]
Type 2 diabetes mellitus (non–insulin-dependent diabetes mellitus [NIDDM]) is a heterogeneous disorder. Most patients with type 2 diabetes mellitus have insulin resistance, and their beta cells lack the ability to overcome this resistance. [6] Although this form of diabetes was previously uncommon in children, in some countries, 20% or more of new patients with diabetes in childhood and adolescence have type 2 diabetes mellitus, a change associated with increased rates of obesity. Other patients may have inherited disorders of insulin release, leading to maturity onset diabetes of the young (MODY) or congenital diabetes. [7, 8, 9] This topic addresses only type 1 diabetes mellitus. (See Etiology and Epidemiology.)
In patients with type 2 diabetes, stress, infection, and medications (such as corticosteroids) can also lead to severely elevated blood sugar levels. Accompanied by dehydration, severe blood sugar elevation in patients with type 2 diabetes can lead to an increase in blood osmolality (hyperosmolar state). This condition can worsen and lead to coma (hyperosmolar coma). A hyperosmolar coma usually occurs in elderly patients with type 2 diabetes. Like diabetic ketoacidosis, a hyperosmolar coma is a medical emergency. Immediate treatment with intravenous fluid and insulin is important in reversing the hyperosmolar state. Unlike patients with type 1 diabetes, patients with type 2 diabetes do not generally develop ketoacidosis solely on the basis of their diabetes. Since in general, type 2 diabetes occurs in an older population, concomitant medical conditions are more likely to be present, and these patients may actually be sicker overall. The complication and death rates from hyperosmolar coma is thus higher than in diabetic ketoacidosis.
In this health topic, we discuss hyperglycemic hyperosmolar nonketotic syndrome (HHNS), an extremely serious complication that can lead to diabetic coma and even death in type 2 diabetes. This serious condition occurs when the blood sugar gets too high and the body becomes severely dehydrated. To prevent HHNS and diabetic coma in type 2 diabetes, check your blood sugar regularly as recommended by your health care provider; check your blood sugar more frequently when you are sick, drink plenty of fluids, and watch for signs of dehydration.
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