The diabetic patient should learn to recognize symptoms of low blood sugar (such as confusion, sweats, and palpitations) and high blood sugar (such as, polyuria and polydipsia). When either condition results in hospitalization, vital signs, weight, fluid intake, urine output, and caloric intake are accurately documented. Serum glucose and urine ketone levels are evaluated. Chronic management of DM is also based on periodic measurement of glycosylated hemoglobin levels (HbA1c). Elevated levels of HbA1c suggest poor long-term glucose control. The effects of diabetes on other body systems (such as cerebrovascular, coronary artery, and peripheral vascular) should be regularly assessed. Patients should be evaluated regularly for retinal disease and visual impairment and peripheral and autonomic nervous system abnormalities, e.g., loss of sensation in the feet. The patient is observed for signs and symptoms of diabetic neuropathy, e.g., numbness or pain in the hands and feet, decreased vibratory sense, footdrop, and neurogenic bladder. The urine is checked for microalbumin or overt protein losses, an early indication of nephropathy. The combination of peripheral neuropathy and peripheral arterial disease results in changes in the skin and microvasculature that lead to ulcer formation on the feet and lower legs with poor healing. Approx. 45,000 lower-extremity diabetic amputations are performed in the U.S. each year. Many amputees have a second amputation within five years. Most of these amputations are preventable with regular foot care and examinations. Diabetic patients and their providers should look for changes in sensation to touch and vibration, the integrity of pulses, capillary refill, and the skin. All injuries, cuts, and blisters should be treated promptly. The patient should avoid constricting hose, slippers, shoes, and bed linens or walking barefoot. The patient with ulcerated or insensitive feet is referred to a podiatrist for continuing foot care and is warned that decreased sensation can mask injuries.
Glucose in your body can cause yeast infections. This is because glucose speeds the growth of fungus. There are over-the-counter and prescription medications to treat yeast infections. You can potentially avoid yeast infections by maintaining better control of your blood sugar. Take insulin as prescribed, exercise regularly, reduce your carb intake, choose low-glycemic foods, and monitor your blood sugar.
Say that two people have the same genetic mutation. One of them eats well, watches their cholesterol, and stays physically fit, and the other is overweight (BMI greater than 25) and inactive. The person who is overweight and inactive is much more likely to develop type 2 diabetes because certain lifestyle choices greatly influence how well your body uses insulin.
Type 1 diabetes in pediatric patients has been linked to changes in cognition and brain structure, with a study by Siller et al finding lower volume in the left temporal-parietal-occipital cortex in young patients with type 1 diabetes than in controls. The study also indicated that in pediatric patients, higher severity of type 1 diabetes presentation correlates with greater structural differences in the brain at about 3 months following diagnosis. The investigators found that among study patients with type 1 diabetes, an association existed between the presence of diabetic ketoacidosis at presentation and reduced radial, axial, and mean diffusivity in the major white matter tracts on magnetic resonance imaging (MRI). In those with higher glycated hemoglobin (HbA1c) levels, hippocampal, thalamic, and cerebellar white matter volumes were lower, as was right posterior parietal cortical thickness, while right occipital cortical thickness was greater. Patients in the study were aged 7-17 years. [43]
Does having type 2 diabetes affect life expectancy? While continued improvements in therapies and care for type 2 diabetes may be helping patients live longer, the unfortunate reality is that type 2 diabetes has been shown to decrease life expectancy by up to ten years, according to Diabetes UK. There is still much to be done to ensure that all patients have access to appropriate healthcare and treatments to live a happier and healthier life with type 2 diabetes.
Type 1 diabetes in pediatric patients has been linked to changes in cognition and brain structure, with a study by Siller et al finding lower volume in the left temporal-parietal-occipital cortex in young patients with type 1 diabetes than in controls. The study also indicated that in pediatric patients, higher severity of type 1 diabetes presentation correlates with greater structural differences in the brain at about 3 months following diagnosis. The investigators found that among study patients with type 1 diabetes, an association existed between the presence of diabetic ketoacidosis at presentation and reduced radial, axial, and mean diffusivity in the major white matter tracts on magnetic resonance imaging (MRI). In those with higher glycated hemoglobin (HbA1c) levels, hippocampal, thalamic, and cerebellar white matter volumes were lower, as was right posterior parietal cortical thickness, while right occipital cortical thickness was greater. Patients in the study were aged 7-17 years. [43]

Polyuria is defined as an increase in the frequency of urination. When you have abnormally high levels of sugar in your blood, your kidneys draw in water from your tissues to dilute that sugar, so that your body can get rid of it through the urine. The cells are also pumping water into the bloodstream to help flush out sugar, and the kidneys are unable to reabsorb this fluid during filtering, which results in excess urination.
The most common test used to diagnose diabetes is the fasting blood glucose. This test measures the glucose levels at a specific moment in time (normal is 80-110 mg/dl). In managing diabetes, the goal is to normalize blood glucose levels. It is generally accepted that by maintaining normalized blood glucose levels, one may delay or even prevent some of the complications associated with diabetes. Measures to manage diabetes include behavioral modification (proper diet, exercise) and drug therapies (oral hypoglycemics, insulin replacement). The choice of therapy prescribed takes into consideration the type and severity of the disease present and patient compliance. The physician may request the patient keep a log of their daily blood glucose measurements, in an effort to better assess therapeutic success. Another commonly obtained test is the hemoglobin A1c (HbA1c), which is a surrogate marker used to assess blood glucose levels over an extended period (2-3 months). This test provides the physician with a good picture of the patient’s glucose levels over time.
The classic symptoms of diabetes are polyuria (frequent urination), polydipsia (increased thirst), polyphagia (increased hunger), and weight loss.[23] Other symptoms that are commonly present at diagnosis include a history of blurred vision, itchiness, peripheral neuropathy, recurrent vaginal infections, and fatigue.[13] Many people, however, have no symptoms during the first few years and are diagnosed on routine testing.[13] A small number of people with type 2 diabetes mellitus can develop a hyperosmolar hyperglycemic state (a condition of very high blood sugar associated with a decreased level of consciousness and low blood pressure).[13]
Purified human insulin is most commonly used, however, insulin from beef and pork sources also are available. Insulin may be given as an injection of a single dose of one type of insulin once a day. Different types of insulin can be mixed and given in one dose or split into two or more doses during a day. Patients who require multiple injections over the course of a day may be able to use an insulin pump that administers small doses of insulin on demand. The small battery-operated pump is worn outside the body and is connected to a needle that is inserted into the abdomen. Pumps can be programmed to inject small doses of insulin at various times during the day, or the patient may be able to adjust the insulin doses to coincide with meals and exercise.

The United Kingdom Prospective Diabetes Study (UKPDS) was a clinical study conducted by Z that was published in The Lancet in 1998. Around 3,800 people with type 2 diabetes were followed for an average of ten years, and were treated with tight glucose control or the standard of care, and again the treatment arm had far better outcomes. This confirmed the importance of tight glucose control, as well as blood pressure control, for people with this condition.[86][132][133]

Patients need to ensure that their blood glucose levels are kept as normal as possible so that delicate tissues in the body (especially blood vessels in the eyes, kidneys and peripheral nerves) are not damaged by high glucose levels over a long period of time. To achieve this, patients need to measure their glucose regularly and learn how to adjust their insulin doses in order to optimise their glucose levels (diabetes control). Good diabetes control helps to minimise the risk of long-term diabetes complications, as well as short-term symptoms (such as thirst).
Some patients with type 2 DM can control their disease with a calorically restricted diet (for instance 1600 to 1800 cal/day), regular aerobic exercise, and weight loss. Most patients, however, require the addition of some form of oral hypoglycemic drug or insulin. Oral agents to control DM include sulfonylurea drugs (such as glipizide), which increase pancreatic secretion of insulin; biguanides or thiazolidinediones (such as metformin or pioglitazone), which increase cellular sensitivity to insulin; or a-glucosidase inhibitors (such as acarbose), which decrease the absorption of carbohydrates from the gastrointestinal tract. Both types of diabetics also may be prescribed pramlintide (Symlin), a synthetic analog of human amylin, a hormone manufactured in the pancreatic beta cells. It enhances postprandial glucose control by slowing gastric emptying, decreasing postprandial glucagon concentrations, and regulating appetite and food intake; thus pramlintide is helpful for patients who do not achieve optimal glucose control with insulin and/or oral antidiabetic agents. When combinations of these agents fail to normalize blood glucose levels, insulin injections are added. Tight glucose control can reduce the patient’s risk of many of the complications of the disease. See: illustration
Type 2 diabetes typically starts with insulin resistance. That is, the cells of the body resist insulin’s efforts to escort glucose into the cells. What causes insulin resistance? It appears to be caused by an accumulation of microscopic fat particles within muscle and liver cells.4 This fat comes mainly from the diet—chicken fat, beef fat, cheese fat, fish fat, and even vegetable fat. To try to overcome insulin resistance, the pancreas produces extra insulin. When the pancreas can no longer keep up, blood sugar rises. The combination of insulin resistance and pancreatic cell failure leads to type 2 diabetes.

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 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.
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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.
How does type 2 diabetes progress over time? Type 2 diabetes is a progressive disease, meaning that the body’s ability to regulate blood sugar gets worse over time, despite careful management. Over time, the body’s cells become increasingly less responsive to insulin (increased insulin resistance) and beta cells in the pancreas produce less and less insulin (called beta-cell burnout). In fact, when people are diagnosed with type 2 diabetes, they usually have already lost up to 50% or more of their beta cell function. As type 2 diabetes progresses, people typically need to add one or more different types of medications. The good news is that there are many more choices available for treatments, and a number of these medications don’t cause as much hypoglycemia, hunger and/or weight gain (e.g., metformin, pioglitazone, DPP-4 inhibitors, GLP-1 agonists, SGLT-2 inhibitors, and better insulin). Diligent management early on can help preserve remaining beta cell function and sometimes slow progression of the disease, although the need to use more and different types of medications does not mean that you have failed.
If sugars in general are not associated with increased diabetes risk, but sodas are, it suggests the possibility that something other than sugar explains this relationship.16 Sodas are often accompanied by cheeseburgers, chicken nuggets, and other unhealthful foods. That is, soda consumption can be a sign of a diet focusing on fast foods or an overall unhealthful diet and lifestyle. And sugary snack foods (e.g., cookies and snack pastries) are often high in fat; the sugar lures us in to the fat calories hiding inside. Some, but not all, observational trials have sought to control for these confounding variables. 
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.

Fatigue and muscle weakness occur because the glucose needed for energy simply is not metabolized properly. Weight loss in type 1 diabetes patients occurs partly because of the loss of body fluid and partly because in the absence of sufficient insulin the body begins to metabolize its own proteins and stored fat. The oxidation of fats is incomplete, however, and the fatty acids are converted into ketone bodies. When the kidney is no longer able to handle the excess ketones the patient develops ketosis. The overwhelming presence of the strong organic acids in the blood lowers the pH and leads to severe and potentially fatal ketoacidosis.
Constant advances are being made in development of new oral medications for persons with diabetes. In 2003, a drug called Metaglip combining glipizide and metformin was approved in a dingle tablet. Along with diet and exercise, the drug was used as initial therapy for Type 2 diabetes. Another drug approved by the U.S. Food and Drug Administration (FDA) combines metformin and rosiglitazone (Avandia), a medication that increases muscle cells' sensitivity to insulin. It is marketed under the name Avandamet. So many new drugs are under development that it is best to stay in touch with a physician for the latest information; physicians can find the best drug, diet and exercise program to fit an individual patient's need.
It is also important to note that currently one third of those who have IGT are in the productive age between 20-39 yr and, therefore, are likely to spend many years at high risk of developing diabetes and/or complications of diabetes1. Some persons with prediabetes experience reactive hypoglycaemia 2-3 hours after a meal. This is a sign of impaired insulin metabolism indicative of impending occurrence of diabetes. Therefore, periodic medical check-up in people with such signs or risk factors for diabetes would reduce the hazards involved in having undiagnosed diabetes. It would help improve the health status of a large number of people who otherwise would be silent sufferers from the metabolic aberrations associated with diabetes.
It isn't always easy to start an exercise regimen, but once you get into a groove, you may be surprised at how much you enjoy it. Find a way to fit activity into your daily routine. Even a few minutes a day goes a long way. The American Diabetes Association recommends that adults with diabetes should perform at least 150 minutes of moderate-intensity aerobic physical activity per week (spread over at least three days with no more than two consecutive days without exercise). You don't have to start with this right away, though. Start with five to 10 minutes per day and go from there. To stay motivated, find a buddy, get a fitness tracker, or use another measurement tool that can help you see your progress.
Prevention and treatment involve maintaining a healthy diet, regular physical exercise, a normal body weight, and avoiding use of tobacco.[2] Control of blood pressure and maintaining proper foot care are important for people with the disease.[2] Type 1 DM must be managed with insulin injections.[2] Type 2 DM may be treated with medications with or without insulin.[9] Insulin and some oral medications can cause low blood sugar.[13] Weight loss surgery in those with obesity is sometimes an effective measure in those with type 2 DM.[14] Gestational diabetes usually resolves after the birth of the baby.[15]
10. Importance of keeping appointments and staying in touch with a health care provider for consultation and assessment. Periodic evaluation of the binding of glucose to hemoglobin (glycosylated hemoglobin or hemoglobin A1C testing) can give information about the effectiveness of the prescribed regimen and whether any changes need to be made. The ADA position statement on tests of glycemia in diabetes recommends routine testing for all patients with diabetes. It should be a part of the initial assessment of the patient, with subsequent measurements every three months to determine if the patient's metabolic control has been reached and maintained.

Diabetes mellitus, or as it's more commonly known diabetes, is a disease characterized by an excess of blood glucose, or blood sugar, which builds up in the bloodstream when your body isn't able to adequately process the sugar in food. High blood sugar is an abnormal state for the body and creates specific symptoms and possible long-term health problems if blood sugar is not managed well.


Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
George P Chrousos, MD, FAAP, MACP, MACE, FRCP(London) is a member of the following medical societies: American Academy of Pediatrics, American College of Physicians, American Pediatric Society, American Society for Clinical Investigation, Association of American Physicians, Endocrine Society, Pediatric Endocrine Society, Society for Pediatric Research, American College of Endocrinology
Doctors and people with diabetes have observed that infections seem more common if you have diabetes. Research in this area, however, has not proved whether this is entirely true, nor why. It may be that high levels of blood sugar impair your body's natural healing process and your ability to fight infections. For women, bladder and vaginal infections are especially common.
Other potentially important mechanisms associated with type 2 diabetes and insulin resistance include: increased breakdown of lipids within fat cells, resistance to and lack of incretin, high glucagon levels in the blood, increased retention of salt and water by the kidneys, and inappropriate regulation of metabolism by the central nervous system.[10] However, not all people with insulin resistance develop diabetes, since an impairment of insulin secretion by pancreatic beta cells is also required.[13]

People with these risk factors should be screened for diabetes at least once every three years. Diabetes risk can be estimated using online risk calculators. Doctors may measure fasting blood glucose levels and hemoglobin A1C level, or do an oral glucose tolerance test. If the test results are on the border between normal and abnormal, doctors do the screening tests more often, at least once a year.
Hemoglobin A1c or HbA1c is a protein on the surface of red blood cells. The HbA1c test is used to monitor blood sugar levels in people with type 1 and type 2 diabetes over time. Normal HbA1c levels are 6% or less. HbA1c levels can be affected by insulin use, fasting, glucose intake (oral or IV), or a combination of these and other factors. High hemoglobin A1c levels in the blood increases the risk of microvascular complications, for example, diabetic neuropathy, eye, and kidney disease.
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