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.
In type 1 diabetes (formerly called insulin-dependent diabetes or juvenile-onset diabetes), the body's immune system attacks the insulin-producing cells of the pancreas, and more than 90% of them are permanently destroyed. The pancreas, therefore, produces little or no insulin. Only about 5 to 10% of all people with diabetes have type 1 disease. Most people who have type 1 diabetes develop the disease before age 30, although it can develop later in life.
Heart disease accounts for approximately 50% of all deaths among people with diabetes in industrialized countries. Risk factors for heart disease in people with diabetes include smoking, high blood pressure, high serum cholesterol and obesity. Diabetes negates the protection from heart disease which pre-menopausal women without diabetes experience. Recognition and management of these conditions may delay or prevent heart disease in people with diabetes.
The WHO estimates that diabetes mellitus resulted in 1.5 million deaths in 2012, making it the 8th leading cause of death. However another 2.2 million deaths worldwide were attributable to high blood glucose and the increased risks of cardiovascular disease and other associated complications (e.g. kidney failure), which often lead to premature death and are often listed as the underlying cause on death certificates rather than diabetes. For example, in 2014, the International Diabetes Federation (IDF) estimated that diabetes resulted in 4.9 million deaths worldwide, using modeling to estimate the total number of deaths that could be directly or indirectly attributed to diabetes.
History of diabetes: Past treatments and new discoveries Diabetes has been known for at least 2,000 years. Over the years, treatments have included exercise, riding on horseback, drinking wine, consuming milk or rice, opium, and overfeeding. It was not until 1921 that insulin was introduced as a treatment. Science has progressed, but diabetes remains a major health problem. Read now
A study by Dabelea et al found that in teenagers and young adults in whom diabetes mellitus had been diagnosed during childhood or adolescence, diabetes-related complications and comorbidities—including diabetic kidney disease, retinopathy, and peripheral neuropathy (but not arterial stiffness or hypertension)—were more prevalent in those with type 2 diabetes than in those with type 1 disease. 
Poorly controlled diabetic patients are at risk for numerous oral complications such as periodontal disease, salivary gland dysfunction, infection, neuropathy, and poor healing. None of these complications are unique to diabetes. However, their presence may serve as an early clue to the possible presence of diabetes, prompting your dentist to perform or request further testing.
There are many complications of diabetes. Knowing and understanding the signs of these complications is important. If caught early, some of these complications can be treated and prevented from getting worse. The best way to prevent complications of diabetes is to keep your blood sugars in good control. High glucose levels produce changes in the blood vessels themselves, as well as in blood cells (primarily erythrocytes) that impair blood flow to various organs.
Lifestyle factors are important to the development of type 2 diabetes, including obesity and being overweight (defined by a body mass index of greater than 25), lack of physical activity, poor diet, stress, and urbanization. Excess body fat is associated with 30% of cases in those of Chinese and Japanese descent, 60–80% of cases in those of European and African descent, and 100% of cases in Pima Indians and Pacific Islanders. Among those who are not obese, a high waist–hip ratio is often present. Smoking appears to increase the risk of type 2 diabetes mellitus.
Several common medications can impair the body's use of insulin, causing a condition known as secondary diabetes. These medications include treatments for high blood pressure (furosemide, clonidine, and thiazide diuretics), drugs with hormonal activity (oral contraceptives, thyroid hormone, progestins, and glucocorticorids), and the anti-inflammation drug indomethacin. Several drugs that are used to treat mood disorders (such as anxiety and depression) also can impair glucose absorption. These drugs include haloperidol, lithium carbonate, phenothiazines, tricyclic antidepressants, and adrenergic agonists. Other medications that can cause diabetes symptoms include isoniazid, nicotinic acid, cimetidine, and heparin. A 2004 study found that low levels of the essential mineral chromium in the body may be linked to increased risk for diseases associated with insulin resistance.
Jump up ^ Cheng J, Zhang W, Zhang X, Han F, Li X, He X, Li Q, Chen J (May 2014). "Effect of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers on all-cause mortality, cardiovascular deaths, and cardiovascular events in patients with diabetes mellitus: a meta-analysis". JAMA Internal Medicine. 174 (5): 773–85. doi:10.1001/jamainternmed.2014.348. PMID 24687000.
The body’s immune system is responsible for fighting off foreign invaders, like harmful viruses and bacteria. In people with type 1 diabetes, the immune system mistakes the body’s own healthy cells for foreign invaders. The immune system attacks and destroys the insulin-producing beta cells in the pancreas. After these beta cells are destroyed, the body is unable to produce insulin.
For example, the environmental trigger may be a virus or chemical toxin that upsets the normal function of the immune system. This may lead to the body’s immune system attacking itself. The normal beta cells in the pancreas may be attacked and destroyed. When approximately 90% of the beta cells are destroyed, symptoms of diabetes mellitus begin to appear. The exact cause and sequence is not fully understood but investigation and research into the disease continues.
Another area of pathologic changes associated with diabetes mellitus is the nervous system (diabetic neuropathy), particularly in the peripheral nerves of the lower extremities. The patient typically experiences a “stocking-type” anesthesia beginning about 10 years after the onset of the disease. There may eventually be almost total anesthesia of the affected part with the potential for serious injury to the part without the patient being aware of it. In contrast, some patients experience debilitating pain and hyperesthesia, with loss of deep tendon reflexes.
Maturity onset diabetes of the young (MODY) is a rare autosomal dominant inherited form of diabetes, due to one of several single-gene mutations causing defects in insulin production. It is significantly less common than the three main types. The name of this disease refers to early hypotheses as to its nature. Being due to a defective gene, this disease varies in age at presentation and in severity according to the specific gene defect; thus there are at least 13 subtypes of MODY. People with MODY often can control it without using insulin.
The amount of glucose in the bloodstream is tightly regulated by insulin and other hormones. Insulin is always being released in small amounts by the pancreas. When the amount of glucose in the blood rises to a certain level, the pancreas will release more insulin to push more glucose into the cells. This causes the glucose levels in the blood (blood glucose levels) to drop.
Certain genetic markers have been shown to increase the risk of developing Type 1 diabetes. Type 2 diabetes is strongly familial, but it is only recently that some genes have been consistently associated with increased risk for Type 2 diabetes in certain populations. Both types of diabetes are complex diseases caused by mutations in more than one gene, as well as by environmental factors.
A type 2 diabetes diet or a type 2 diabetic diet is important for blood sugar (glucose) control in people with diabetes to prevent complications of diabetes. There are a variety of type 2 diabetes diet eating plans such as the Mediterranean diet, Paleo diet, ADA Diabetes Diet, and vegetarian diets.Learn about low and high glycemic index foods, what foods to eat, and what foods to avoid if you have type 2 diabetes.
To treat diabetic retinopathy, a laser is used to destroy and prevent the recurrence of the development of these small aneurysms and brittle blood vessels. Approximately 50% of patients with diabetes will develop some degree of diabetic retinopathy after 10 years of diabetes, and 80% retinopathy after 15 years of the disease. Poor control of blood sugar and blood pressure further aggravates eye disease in diabetes.
If eaten as part of a healthy meal plan, or combined with exercise, sweets and desserts can be eaten by people with diabetes. They are no more "off limits" to people with diabetes than they are to people without diabetes. The key to sweets is to have a very small portion and save them for special occasions so you focus your meal on more healthful foods.
In countries using a general practitioner system, such as the United Kingdom, care may take place mainly outside hospitals, with hospital-based specialist care used only in case of complications, difficult blood sugar control, or research projects. In other circumstances, general practitioners and specialists share care in a team approach. Home telehealth support can be an effective management technique.
Get Educated: The American Diabetes Association advises that all persons with diabetes receive diabetes self-management education (DSME) at diagnosis and thereafter. A certified diabetes educator or other qualified health professional can give you the tools you need to understand and take care of your diabetes. In addition, these individuals are trained to create a customized plan that works for you. Diabetes self-management education is a patient-centered approach that enables patients to get involved in their care.
Women seem to be at a greater risk as do certain ethnic groups, such as South Asians, Pacific Islanders, Latinos, and Native Americans. This may be due to enhanced sensitivity to a Western lifestyle in certain ethnic groups. Traditionally considered a disease of adults, type 2 diabetes is increasingly diagnosed in children in parallel with rising obesity rates. Type 2 diabetes is now diagnosed as frequently as type 1 diabetes in teenagers in the United States.
Type 2 diabetes is a condition of blood sugar dysregulation. In general blood sugar is too high, but it also can be too low. This can happen if you take medications then skip a meal. Blood sugar also can rise very quickly after a high glycemic index meal, and then fall a few hours later, plummeting into hypoglycemia (low blood sugar). The signs and symptoms of hypoglycemia can include
At present, the American Diabetes Association does not recommend general screening of the population for type 1 diabetes, though screening of high risk individuals, such as those with a first degree relative (sibling or parent) with type 1 diabetes should be encouraged. Type 1 diabetes tends to occur in young, lean individuals, usually before 30 years of age; however, older patients do present with this form of diabetes on occasion. This subgroup is referred to as latent autoimmune diabetes in adults (LADA). LADA is a slow, progressive form of type 1 diabetes. Of all the people with diabetes, only approximately 10% have type 1 diabetes and the remaining 90% have type 2 diabetes.
Good metabolic control can delay the onset and progression of diabetic retinopathy. Loss of vision and blindness in persons with diabetes can be prevented by early detection and treatment of vision-threatening retinopathy: regular eye examinations and timely intervention with laser treatment, or through surgery in cases of advanced retinopathy. There is evidence that, even in developed countries, a large proportion of those in need is not receiving such care due to lack of public and professional awareness, as well as an absence of treatment facilities. In developing countries, in many of which diabetes is now common, such care is inaccessible to the majority of the population.
The glucose level at which symptoms develop varies greatly from individual to individual (and from time to time in the same individual), depending in part on the duration of diabetes, the frequency of hypoglycemic episodes, the rate of fall of glycemia, and overall control. (Glucose is also the sole energy source for erythrocytes and the kidney medulla.)
Manage mild hypoglycemia by giving rapidly absorbed oral carbohydrate or glucose; for a comatose patient, administer an intramuscular injection of the hormone glucagon, which stimulates the release of liver glycogen and releases glucose into the circulation. Where appropriate, an alternative therapy is intravenous glucose (preferably no more than a 10% glucose solution). All treatments for hypoglycemia provide recovery in approximately 10 minutes. (See Treatment.)
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In general, women live longer than men do because they have a lower risk of heart disease, but when women develop diabetes, their risk for heart disease skyrockets, and death by heart failure is more likely in women than in men. Another study also found that in people with diabetes, heart attacks are more often fatal for women than they are for men. Other examples of how diabetes affects women differently than men are: