Prediabetes
Classification and external resources
ICD-10	R73.0
ICD-9	790.29
MeSH	D011236

Prediabetes is the state in which some but not all of the diagnostic criteria for diabetes are met.^[1] It is often described as the “gray area” between normal blood sugar and diabetic levels. While in this range, patients are at risk for not only developing type 2 diabetes, but also for cardiovascular complications.^[2] It has been termed "America's largest healthcare epidemic," affecting more than 57 million Americans.^[3] Prediabetes is also referred to as borderline diabetes, impaired glucose tolerance (IGT), and/or impaired fasting glucose (IFG).^{[citation needed]}

Diabetes mellitus Related articles
Types of diabetes
Diabetes mellitus type 1 Diabetes mellitus type 2 Gestational diabetes Prediabetes:    • Impaired fasting glycaemia    • Impaired glucose tolerance
Blood tests
Blood sugar Glycosylated hemoglobin Glucose tolerance test Fructosamine
Disease management
Diabetes management:    • Anti-diabetic drugs    • Conventional insulinotherapy    • Diabetic diet    • Intensive insulinotherapy Glossary of diabetes
Complications
Cardiovascular disease Diabetic comas:    • Diabetic hypoglycemia    • Diabetic ketoacidosis    • Nonketotic hyperosmolar Diabetic myonecrosis Diabetic nephropathy Diabetic neuropathy Diabetic retinopathy Diabetes and pregnancy

Contents 1 Risk factors 2 Prevention 3 Signs and symptoms 4 Screening 5 Diagnosis 6 Risks of not treating 7 Treatment and management 8 Prognosis 9 Genetics 10 Pathophysiology 11 Epidemiology 12 References

[edit] Risk factors

• Family history of diabetes
• Impaired glucose levels and/or metabolic syndrome
• Cardiovascular disease
• Hypertension (high blood pressure)
• Increased triglycerides levels
• Low levels of good cholesterol (HDL)
• Overweight or obese
• Women who have had gestational diabetes, had high birth weight babies (greater than 9 lbs.), and/or has Polycystic Ovarian Syndrome (PCOS)^[4]

These are associated with insulin resistance and are risk factors for the development of type 2 diabetes mellitus. Those in this stratum (IGT or IFG) are at increased risk of cardiovascular disease. Of the two, impaired glucose tolerance better predicts cardiovascular disease and mortality.^[5][6][7]

In a way, prediabetes is a misnomer since it is an early stage of diabetes. It is now known that the health complications associated with type 2 diabetes often occur before the medical diagnosis of diabetes is made.^[8]

[edit] Prevention

The goals of prevention are to delay the onset of type 2 diabetes, preserving the function of the beta cells, and preventing or delaying the microvascular and cardiovascular complications. Obesity is an extremely important environmental influence, therefore, exercise, weight loss, and drug therapies have been studied. It has been found that lifestyle modification/intervention provides the greatest benefit in preventing the progression into type 2 diabetes.^[9]

The American College of Endocrinology (ACE) and the American Association of Clinical Endocrinologists (AACE) have developed lifestyle intervention guidelines for preventing the onset of type 2 diabetes:

• Healthy meals (low in salt)
• Physical exercise (30 to 60 minutes of exercise at least five days a week)
• Reducing weight by as little as 5-10 percent can have a significant impact on decreased fat mass, blood pressure, and glucose.

Many studies showed that low-carb diet is a very valuable prevention and treatment tool in diabetes and prediabetes.^[10][11] Previous advice focused on low-fat approach.^[12]

[edit] Signs and symptoms

Prediabetes typically has no signs or symptoms. Patients should monitor for signs and symptoms of type 2 diabetes mellitus. These include the following:^[13]

• Constant hunger
• Unexplained weight loss
• Weight gain
• Flu-like symptoms, including weakness and fatigue
• Blurred vision
• Slow healing of cuts or bruises
• Tingling or loss of feeling in hands or feet
• Recurring gum or skin infections
• Recurring vaginal or bladder infections

[edit] Screening

Fasting plasma glucose screening should begin at age 30-45 and be repeated at least every three years. Earlier and more frequent screening should be conducted in at-risk individuals. The risk factors for which are listed below:

• Family history (parent or sibling)
• Dyslipidemia (triglycerides > 200 or HDL < 35)
• Overweight or obese (body mass index > 25)
• History of gestational diabetes or infant born with birth weight greater than 9 lb (4 kg)
• High risk ethnic group
• Hypertension (systolic blood pressure >140 mmHg or diastolic blood pressure > 90 mmHg)
• Prior fasting blood glucose > 99
• Known vascular disease
• Markers of insulin resistance (PCOS, acanthosis nigricans)^[14][15]

[edit] Diagnosis

Prediabetes is usually diagnosed with a fasting blood sugar after an overnight fast or measuring the blood sugar level two hours after drinking a standardized glucose solution.^[3] The fasting blood sugar (glucose) level must be greater than 99 but less than 126 mg%; two hours after ingesting the standardized sugar solution the blood sugar is between 140 and 200 mg%.^[3] A random glucose level over 140 at any time can result in the diagnosis of prediabetes.^[6]

[edit] Risks of not treating

Persons with prediabetes actually have the same complications as persons with diabetes—only less frequently. They run the risk of developing diabetic eye disease, nerve damage, and early diabetic kidney disease with excess protein in the urine. Patients with prediabetes are also thought to already have an increased risk of heart and blood vessel disease.^[3]

[edit] Treatment and management

Intensive weight loss and lifestyle intervention, if sustained, can substantially improve glucose tolerance and prevent progression from IGT to type 2 diabetes. The Diabetes Prevention Program (DPP)^[16] study found a 16% reduction in diabetes risk for every kilogram of weight loss. Reducing weight by 7% through a low-fat diet and performing 150 minutes of exercise a week is the goal. The ADA guidelines^[17] recommend modest weight loss (5-10% body weight), moderate-intensity exercise (30 minutes daily), and smoking cessation.

For patients with severe risk factors, prescription medication may be appropriate. This can be considered in patients for whom lifestyle therapy has failed or is not sustainable and who are at high-risk for developing type 2 diabetes.^[9] Metformin^[18] and acarbose help prevent the development of frank diabetes, and also have a good safety profile. Evidence also supports thiazolidinediones but there are safety concerns, and data on newer agents such as GLP-1 receptor agonists, DPP4 inhibitors or meglitinides are lacking.^[19]

[edit] Prognosis

The progression to type 2 diabetes mellitus is not inevitable for those with prediabetes. The progression into diabetes mellitus from prediabetes is approximately 25% over three to five years ^[20]

[edit] Genetics

As the human genome is further explored, it is likely that multiple genetic anomalies at different loci will be found that confer varying degrees of predisposition to type 2 diabetes.^[21] Type 2 DM, which is the condition for which prediabetes is a precursor, has 90-100% concordance in twins; there is no HLA association.^[22] However, genetics play a relatively small role in the widespread occurrence of type 2 diabetes. This can be logically deduced from the huge increase in the occurrence of type 2 diabetes which has correlated with the significant change in western lifestyle.^[22]

[edit] Pathophysiology

Diabetes mellitus (DM) is a group of metabolic diseases that are characterized by hyperglycemia and defects in insulin production in the pancreas and/or impaired tolerance to insulin effects. DM is a leading cause of morbidity and mortality. Because the disease can be insidious, the diagnosis is often delayed. Effects of the disease can be macrovascular, as seen in the cardiovascular system/arthrosclerosis, or microvascular, as seen with retinopathy, nephropathy, and neuropathy.^[22]

Normal glucose homeostasis is controlled by three interrelated processes. There is gluconeogenesis (glucose production that occurs in the liver), uptake and utilization of glucose by the peripheral tissues of the body, and insulin secretion by the pancreatic islet cells. What triggers the production and release of insulin from the pancreas is the presence of glucose in the body. The main function of insulin is to increase the rate of transport of glucose into certain cells of the body, such as striated muscles, fibroblasts, and fat cells. It is also necessary for transport of amino acids, glycogen formation in the liver and skeletal muscles, triglyceride formation from glucose, nucleic acid synthesis, and protein synthesis.

Insulin enters cells by first binding to target insulin receptors. DM and some of those with prediabetes have impaired glucose tolerance—in these individuals, blood glucose rises to abnormally high levels. This may be from a lack of pancreatic hormone release or failure of target tissues to respond to the insulin present or both.^[22]

[edit] Epidemiology

Studies conducted from 1988-1994 indicated that at that time, 33.8% of the US population 40–74 years of age had IFG, 15.4% had IGT, and 40.1% had prediabetes (IFG, IGT, or both). Eighteen million people (6.3% of the population) had type 2 diabetes in 2002.^[23]

[edit] References

v • d • e Abnormal clinical and laboratory findings for blood tests (R70-R79, 790) Red blood cells Size Macrocyte · Microcyte · Anisocytosis Shape (Poikilocyte) membrane abnormalities: Acanthocyte · Codocyte · Ovalocyte · Spherocyte trauma: Dacrocyte · Schistocyte Inclusion bodies developmental organelles (Howell-Jolly body, Basophilic stippling, Pappenheimer bodies, Cabot rings) abnormal hemoglobin precipitation (Heinz body) Other Rouleaux · Reticulocyte · Elevated ESR Lymphocytes Smudge cell · Downey cell Small molecules blood sugar: Abnormal glucose tolerance test · Hyperglycemia · Impaired glucose tolerance · Prediabetes nitrogenous: Azotemia · Hyperuricemia · Hypouricemia Proteins Elevated transaminases · Elevated alkaline phosphatase · Elevated cardiac markers · Elevated alpha-fetoprotein · Hypoproteinemia (Hypoalbuminemia) Minerals Iron overload disorder Pathogens/sepsis Bacteremia · Viremia · Fungemia · Parasitemia · Algaemia see also blood tests