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
Normally, blood glucose levels are tightly controlled by insulin, a hormone produced by the pancreas. Insulin lowers the blood glucose level. When the blood glucose elevates (for example, after eating food), insulin is released from the pancreas to normalize the glucose level by promoting the uptake of glucose into body cells. In patients with diabetes, the absence of insufficient production of or lack of response to insulin causes hyperglycemia. Diabetes is a chronic medical condition, meaning that although it can be controlled, it lasts a lifetime.
There is no known preventive measure for type 1 diabetes.[2] Type 2 diabetes – which accounts for 85–90% of all cases – can often be prevented or delayed by maintaining a normal body weight, engaging in physical activity, and consuming a healthy diet.[2] Higher levels of physical activity (more than 90 minutes per day) reduce the risk of diabetes by 28%.[71] Dietary changes known to be effective in helping to prevent diabetes include maintaining a diet rich in whole grains and fiber, and choosing good fats, such as the polyunsaturated fats found in nuts, vegetable oils, and fish.[72] Limiting sugary beverages and eating less red meat and other sources of saturated fat can also help prevent diabetes.[72] Tobacco smoking is also associated with an increased risk of diabetes and its complications, so smoking cessation can be an important preventive measure as well.[73]
Diabetes also can cause heart disease and stroke, as well as other long-term complications, including eye problems, kidney disease, nerve damage, and gum disease. While these problems don't usually show up in kids or teens who've had type 2 diabetes for only a few years, they can affect them in adulthood, particularly if their diabetes isn't well controlled.
Although age of onset and length of the disease process are related to the frequency with which vascular, renal, and neurologic complications develop, there are some patients who remain relatively free of sequelae even into the later years of their lives. Because diabetes mellitus is not a single disease but rather a complex constellation of syndromes, each patient has a unique response to the disease process.
There is currently no cure for diabetes. The condition, however, can be managed so that patients can live a relatively normal life. Treatment of diabetes focuses on two goals: keeping blood glucose within normal range and preventing the development of long-term complications. Careful monitoring of diet, exercise, and blood glucose levels are as important as the use of insulin or oral medications in preventing complications of diabetes. In 2003, the American Diabetes Association updated its Standards of Care for the management of diabetes. These standards help manage health care providers in the most recent recommendations for diagnosis and treatment of the disease.
Because both yeast and bacteria multiply more quickly when blood sugar levels are elevated, women with diabetes are overall at a higher risk of feminine health issues, such as bacterial infections, yeast infections, and vaginal thrush, especially when blood sugar isn't well controlled. And a lack of awareness about having prediabetes or diabetes can make managing blood sugar impossible.
Diabetic ketoacidosis can be caused by infections, stress, or trauma, all of which may increase insulin requirements. In addition, missing doses of insulin is also an obvious risk factor for developing diabetic ketoacidosis. Urgent treatment of diabetic ketoacidosis involves the intravenous administration of fluid, electrolytes, and insulin, usually in a hospital intensive care unit. Dehydration can be very severe, and it is not unusual to need to replace 6-7 liters of fluid when a person presents in diabetic ketoacidosis. Antibiotics are given for infections. With treatment, abnormal blood sugar levels, ketone production, acidosis, and dehydration can be reversed rapidly, and patients can recover remarkably well.
2.Retinopathy - Diabetes may cause blood vessels in the retina (the light sensitive lining of the eye) to become leaky, blocked, or grow abnormally [Figure 1]. Retinopathy is rare before the age of 10 and the risk increases with the length of time a person has diabetes. Treatments such as laser, injections in the eye, or other procedures may be helpful to prevent visual loss or restore sight. The longer a patient has diabetes, the greater chance of developing an eye problem.  All patients with diabetes are at risk for developing retinopathy, but the risk is higher for patients with worse blood sugar control.  Early retinopathy may have no symptoms, but early treatment is essential to prevent any loss of vision.
A second oral agent of another class or insulin may be added if metformin is not sufficient after three months.[76] Other classes of medications include: sulfonylureas, thiazolidinediones, dipeptidyl peptidase-4 inhibitors, SGLT2 inhibitors, and glucagon-like peptide-1 analogs.[76] As of 2015 there was no significant difference between these agents.[76] A 2018 review found that SGLT2 inhibitors may be better than glucagon-like peptide-1 analogs or dipeptidyl peptidase-4 inhibitors.[92]
Onset of type 2 diabetes can be delayed or prevented through proper nutrition and regular exercise.[60][61] Intensive lifestyle measures may reduce the risk by over half.[24][62] The benefit of exercise occurs regardless of the person's initial weight or subsequent weight loss.[63] High levels of physical activity reduce the risk of diabetes by about 28%.[64] Evidence for the benefit of dietary changes alone, however, is limited,[65] with some evidence for a diet high in green leafy vegetables[66] and some for limiting the intake of sugary drinks.[32] In those with impaired glucose tolerance, diet and exercise either alone or in combination with metformin or acarbose may decrease the risk of developing diabetes.[24][67] Lifestyle interventions are more effective than metformin.[24] A 2017 review found that, long term, lifestyle changes decreased the risk by 28%, while medication does not reduce risk after withdrawal.[68] While low vitamin D levels are associated with an increased risk of diabetes, correcting the levels by supplementing vitamin D3 does not improve that risk.[69]
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.)
2. Home glucose monitoring using either a visually read test or a digital readout of the glucose concentration in a drop of blood. Patients can usually learn to use the necessary equipment and perform finger sticks. They keep a daily record of findings and are taught to adjust insulin dosage accordingly. More recent glucose monitoring devices can draw blood from other locations on the body, such as the forearm.

Fasting glucose test This test involves giving a blood sample after you have fasted for eight hours. (18) If you have a fasting blood sugar level of less than 100 milligrams per deciliter (mg/dl), your blood sugar levels are normal. But if you have one from 100 to 125 mg/dl, you have prediabetes, and if you have 126 mg/dl on two separate occasions, you have diabetes. (17)
People with diabetes aim for a hemoglobin A1C level of less than 7%. Achieving this level is difficult, but the lower the hemoglobin A1C level, the less likely people are to have complications. Doctors may recommend a slightly higher or lower target for certain people depending on their particular health situation. However, levels above 9% show poor control, and levels above 12% show very poor control. Most doctors who specialize in diabetes care recommend that hemoglobin A1C be measured every 3 to 6 months.
Diabetes mellitus is a chronic disease for which there is treatment but no known cure.  Treatment is aimed at keeping blood glucose levels as close to normal as possible.  This is achieved with a combination of diet, exercise and insulin or oral medication.  People with type 1 diabetes need to be hospitalized right after they are diagnosed to get their glucose levels down to an acceptable level.

The American Diabetes Association recommends that blood sugars be 80mg/dL-130mg/dL before meals and less than or equal to 180mg/dL two hours after meals. Blood sugar targets are individualized based on a variety of factors such as age, length of diagnosis, if you have other health issues, etc. For example, if you are an elderly person, your targets maybe a bit higher than someone else. Ask your physician what targets are right for you.
That said, some research does suggest that eating too many sweetened foods can affect type 2 diabetes risk, and with the Centers for Disease Control and Prevention (CDC) estimating that 30.3 million Americans have the disease — and that millions of more individuals are projected to develop it, too — understanding all the risk factors for the disease, including sugar consumption, is essential to help reverse the diabetes epidemic.
Exposure to certain viral infections (mumps and Coxsackie viruses) or other environmental toxins may serve to trigger abnormal antibody responses that cause damage to the pancreas cells where insulin is made. Some of the antibodies seen in type 1 diabetes include anti-islet cell antibodies, anti-insulin antibodies and anti-glutamic decarboxylase antibodies. These antibodies can be detected in the majority of patients, and may help determine which individuals are at risk for developing type 1 diabetes.
Jump up ^ Palmer, Suetonia C.; Mavridis, Dimitris; Nicolucci, Antonio; Johnson, David W.; Tonelli, Marcello; Craig, Jonathan C.; Maggo, Jasjot; Gray, Vanessa; De Berardis, Giorgia; Ruospo, Marinella; Natale, Patrizia; Saglimbene, Valeria; Badve, Sunil V.; Cho, Yeoungjee; Nadeau-Fredette, Annie-Claire; Burke, Michael; Faruque, Labib; Lloyd, Anita; Ahmad, Nasreen; Liu, Yuanchen; Tiv, Sophanny; Wiebe, Natasha; Strippoli, Giovanni F.M. (19 July 2016). "Comparison of Clinical Outcomes and Adverse Events Associated With Glucose-Lowering Drugs in Patients With Type 2 Diabetes". JAMA: the Journal of the American Medical Association. 316 (3): 313–24. doi:10.1001/jama.2016.9400. PMID 27434443.
Blood sugar should be regularly monitored so that any problems can be detected and treated early. Treatment involves lifestyle changes such as eating a healthy and balanced diet and regular physical exercise. If lifestyle changes alone are not enough to regulate the blood glucose level, anti-diabetic medication in the form of tablets or injections may be prescribed. In some cases, people who have had type 2 diabetes for many years are eventually prescribed insulin injections.

Being overweight is a risk factor for developing diabetes, but other risk factors such as how much physical activity you get, family history, ethnicity, and age also play a role. Unfortunately, many people think that weight is the only risk factor for type 2 diabetes, but many people with type 2 diabetes are at a normal weight or only moderately overweight.
Although there are dozens of known type 1 genes, about half of the risk attributable to heredity comes from a handful that coordinate a part of the immune system called HLA, which helps the body recognize nefarious foreign invaders, such as viruses, bacteria, and parasites. Type 1 diabetes is an autoimmune disease, in which the body's own immune system destroys the cells in the pancreas that produce insulin, so perhaps it is no surprise that immunity genes are involved. Other autoimmune diseases share the HLA gene link, which may be why people with type 1 are more likely to develop additional auto­immune disorders.
Diabetes can occur temporarily during pregnancy, and reports suggest that it occurs in 2% to 10% of all pregnancies. Significant hormonal changes during pregnancy can lead to blood sugar elevation in genetically predisposed individuals. Blood sugar elevation during pregnancy is called gestational diabetes. Gestational diabetes usually resolves once the baby is born. However, 35% to 60% of women with gestational diabetes will eventually develop type 2 diabetes over the next 10 to 20 years, especially in those who require insulin during pregnancy and those who remain overweight after their delivery. Women with gestational diabetes are usually asked to undergo an oral glucose tolerance test about six weeks after giving birth to determine if their diabetes has persisted beyond the pregnancy, or if any evidence (such as impaired glucose tolerance) is present that may be a clue to a risk for developing diabetes.
Unexplained weight loss can happen for lots of reasons, and diabetes is one of them. Goundan explains that insulin helps your body move sugar from your blood to your cells, so when you have an insulin resistance, you don’t get enough energy into your cells despite all that sugar flowing through your body. “Because you’re unable to get enough energy from sugar, your body burns your own fat and muscle for energy," Kellis says. "Weight loss can be pretty significant, sometimes 10 to 20 pounds."