Impaired fasting glucose

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Impaired fasting glucose
Other namesImpaired fasting glycemia, IFG
Suckale08 fig3 glucose insulin day.png
The fluctuation of blood sugar (red) and the sugar-lowering hormone insulin (blue) in humans during the course of a day with three meals. One of the effects of a sugar-rich vs a starch-rich meal is highlighted. [1]

Impaired fasting glucose is a type of prediabetes, in which a person's blood sugar levels during fasting are consistently above the normal range, but below the diagnostic cut-off for a formal diagnosis of diabetes mellitus. [2] Together with impaired glucose tolerance, it is a sign of insulin resistance. In this manner, it is also one of the conditions associated with metabolic syndrome.

Contents

Those with impaired fasting glucose are at an increased risk of vascular complications of diabetes, though to a lesser extent. The risks are cumulative, with both higher blood glucose levels, and the total amount of time it spends elevated, increasing the overall complication rate.

IFG can eventually progress to type 2 diabetes mellitus without intervention, which typically involves lifestyle modification. Those with impaired fasting glucose have a 1.5 fold increased risk of developing clinical diabetes within 10 years, when compared to the general population. Some studies suggest that without lifestyle changes, IFG will progress to clinically diagnosable diabetes in just under 3 years, on average. [3]

Impaired fasting glucose is often, though not always, associated with impaired glucose tolerance, though it may occur in isolation, with such persons having a normal response to a glucose tolerance test.

Signs and symptoms

Impaired fasting glucose is often without any signs or symptoms, other than higher than normal glucose levels being detected in an individual's fasting blood sample. There may be signs and symptoms associated with elevated blood glucose, though these are likely to be minor, with significant symptoms suggestive of complete progression to type 2 diabetes. Such symptoms include: [4]

Risk factors

As impaired fasting glucose is considered a precursor condition for type 2 diabetes, it shares the same environmental and genetic risk factors.[ citation needed ]

Diagnosis

Different organisations use slightly differing levels before classifying a person's fasting blood glucose as "impaired", with the American Diabetes Association using a lower cutoff in its criteria than the World Health Organization. The upper limits remain the same, as fasting levels above this are almost universally accepted as indicative of full diabetes:

Prevention

The guidelines for preventing impaired fasting glucose are the same as those given for preventing type 2 diabetes in general. If these are adhered to, the progression to clinical diabetes can be slowed or halted. In some cases, a complete reversal of IFG can be achieved. Certain risk factors, such as being of Afro-Caribbean or South Asian ethnicity, as well as increasing age, are unavoidable, and such individuals may be advised to follow these guidelines, as well as monitor their blood glucose levels, more closely.[ citation needed ]

Management

Related Research Articles

<span class="mw-page-title-main">Metabolic syndrome</span> Medical condition

Metabolic syndrome is a clustering of at least three of the following five medical conditions: abdominal obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum high-density lipoprotein (HDL).

Insulin resistance (IR) is a pathological condition in which cells either fail to respond normally to the hormone insulin or downregulate insulin receptors in response to hyperinsulinemia.

The following is a glossary of diabetes which explains terms connected with diabetes.

<span class="mw-page-title-main">Diabetic ketoacidosis</span> Medical condition

Diabetic ketoacidosis (DKA) is a potentially life-threatening complication of diabetes mellitus. Signs and symptoms may include vomiting, abdominal pain, deep gasping breathing, increased urination, weakness, confusion and occasionally loss of consciousness. A person's breath may develop a specific "fruity" smell. The onset of symptoms is usually rapid. People without a previous diagnosis of diabetes may develop DKA as the first obvious symptom.

<span class="mw-page-title-main">Glucose tolerance test</span> Medical test of how quickly glucose is cleared from the blood

The glucose tolerance test is a medical test in which glucose is given and blood samples taken afterward to determine how quickly it is cleared from the blood. The test is usually used to test for diabetes, insulin resistance, impaired beta cell function, and sometimes reactive hypoglycemia and acromegaly, or rarer disorders of carbohydrate metabolism. In the most commonly performed version of the test, an oral glucose tolerance test (OGTT), a standard dose of glucose is ingested by mouth and blood levels are checked two hours later. Many variations of the GTT have been devised over the years for various purposes, with different standard doses of glucose, different routes of administration, different intervals and durations of sampling, and various substances measured in addition to blood glucose.

<span class="mw-page-title-main">Hyperglycemia</span> Too much blood sugar, usually because of diabetes

Hyperglycemia is a condition in which an excessive amount of glucose circulates in the blood plasma. This is generally a blood sugar level higher than 11.1 mmol/L (200 mg/dL), but symptoms may not start to become noticeable until even higher values such as 13.9–16.7 mmol/L (~250–300 mg/dL). A subject with a consistent range between ~5.6 and ~7 mmol/L is considered slightly hyperglycemic, and above 7 mmol/L is generally held to have diabetes. For diabetics, glucose levels that are considered to be too hyperglycemic can vary from person to person, mainly due to the person's renal threshold of glucose and overall glucose tolerance. On average, however, chronic levels above 10–12 mmol/L (180–216 mg/dL) can produce noticeable organ damage over time.

<span class="mw-page-title-main">Type 2 diabetes</span> Type of diabetes mellitus with high blood sugar and insulin resistance

Type 2 diabetes, formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent urination, and unexplained weight loss. Symptoms may also include increased hunger, feeling tired, and sores (wounds) that do not heal. Often symptoms come on slowly. Long-term complications from high blood sugar include heart disease, strokes, diabetic retinopathy which can result in blindness, kidney failure, and poor blood flow in the limbs which may lead to amputations. The sudden onset of hyperosmolar hyperglycemic state may occur; however, ketoacidosis is uncommon.

<span class="mw-page-title-main">Blood sugar level</span> Concentration of glucose present in the blood (Glycaemia)

The blood sugar level, blood sugar concentration, blood glucose level, or glycemia, is the measure of glucose concentrated in the blood. The body tightly regulates blood glucose levels as a part of metabolic homeostasis.

<span class="mw-page-title-main">Gestational diabetes</span> Medical condition

Gestational diabetes is a condition in which a woman without diabetes develops high blood sugar levels during pregnancy. Gestational diabetes generally results in few symptoms; however, it increases the risk of pre-eclampsia, depression, and of needing a Caesarean section. Babies born to mothers with poorly treated gestational diabetes are at increased risk of macrosomia, of having hypoglycemia after birth, and of jaundice. If untreated, diabetes can also result in stillbirth. Long term, children are at higher risk of being overweight and of developing type 2 diabetes.

Glycated hemoglobin is a form of hemoglobin (Hb) that is chemically linked to a sugar. Most monosaccharides, including glucose, galactose and fructose, spontaneously bond with hemoglobin when present in the bloodstream. However, glucose is less likely to do so than galactose and fructose, which may explain why glucose is used as the primary metabolic fuel in humans.

<span class="mw-page-title-main">Type 1 diabetes</span> Form of diabetes mellitus

Type 1 diabetes (T1D), formerly known as juvenile diabetes, is an autoimmune disease that originates when cells that make insulin are destroyed by the immune system. Insulin is a hormone required for the cells to use blood sugar for energy and it helps regulate glucose levels in the bloodstream. Before treatment this results in high blood sugar levels in the body. The common symptoms of this elevated blood sugar are frequent urination, increased thirst, increased hunger, weight loss, and other serious complications. Additional symptoms may include blurry vision, tiredness, and slow wound healing. Symptoms typically develop over a short period of time, often a matter of weeks if not months.

The term diabetes includes several different metabolic disorders that all, if left untreated, result in abnormally high concentrations of a sugar called glucose in the blood. Diabetes mellitus type 1 results when the pancreas no longer produces significant amounts of the hormone insulin, usually owing to the autoimmune destruction of the insulin-producing beta cells of the pancreas. Diabetes mellitus type 2, in contrast, is now thought to result from autoimmune attacks on the pancreas and/or insulin resistance. The pancreas of a person with type 2 diabetes may be producing normal or even abnormally large amounts of insulin. Other forms of diabetes mellitus, such as the various forms of maturity-onset diabetes of the young, may represent some combination of insufficient insulin production and insulin resistance. Some degree of insulin resistance may also be present in a person with type 1 diabetes.

Many types of glucose tests exist and they can be used to estimate blood sugar levels at a given time or, over a longer period of time, to obtain average levels or to see how fast body is able to normalize changed glucose levels. Eating food for example leads to elevated blood sugar levels. In healthy people these levels quickly return to normal via increased cellular glucose uptake which is primarily mediated by increase in blood insulin levels.

<span class="mw-page-title-main">Diabetes and pregnancy</span> Effects of pre-existing diabetes upon pregnancy

For pregnant women with diabetes, some particular challenges exist for both mother and fetus. If the pregnant woman has diabetes as a pre-existing disorder, it can cause early labor, birth defects, and larger than average infants. Therefore, experts advise diabetics to maintain blood sugar level close to normal range about 3 months before planning for pregnancy.

Slowly evolving immune-mediated diabetes, or latent autoimmune diabetes in adults (LADA), is a form of diabetes that exhibits clinical features similar to both type 1 diabetes (T1D) and type 2 diabetes (T2D), and is sometimes referred to as type 1.5 diabetes. It is an autoimmune form of diabetes, similar to T1D, but patients with LADA often show insulin resistance, similar to T2D, and share some risk factors for the disease with T2D. Studies have shown that LADA patients have certain types of antibodies against the insulin-producing cells, and that these cells stop producing insulin more slowly than in T1D patients.

Hyperosmolar hyperglycemic state (HHS), also known as hyperosmolar non-ketotic state (HONK), is a complication of diabetes mellitus in which high blood sugar results in high osmolarity without significant ketoacidosis. Symptoms include signs of dehydration, weakness, leg cramps, vision problems, and an altered level of consciousness. Onset is typically over days to weeks. Complications may include seizures, disseminated intravascular coagulopathy, mesenteric artery occlusion, or rhabdomyolysis.

<span class="mw-page-title-main">Prediabetes</span> Predisease state of hyperglycemia with high risk for diabetes

Prediabetes is a component of the metabolic syndrome and is characterized by elevated blood sugar levels that fall below the threshold to diagnose diabetes mellitus. It usually does not cause symptoms but people with prediabetes often have obesity, dyslipidemia with high triglycerides and/or low HDL cholesterol, and hypertension. It is also associated with increased risk for cardiovascular disease (CVD). Prediabetes is more accurately considered an early stage of diabetes as health complications associated with type 2 diabetes often occur before the diagnosis of diabetes.

Complications of diabetes are secondary diseases that are a result of elevated blood glucose levels that occur in diabetic patients. These complications can be divided into two types: acute and chronic. Acute complications are complications that develop rapidly and can be exemplified as diabetic ketoacidosis (DKA), hyperglycemic hyperosmolar state (HHS), lactic acidosis (LA), and hypoglycemia. Chronic complications develop over time and are generally classified in two categories: microvascular and macrovascular. Microvascular complications include neuropathy, nephropathy, and retinopathy; while cardiovascular disease, stroke, and peripheral vascular disease are included in the macrovascular complications.

The following outline is provided as an overview of and topical guide to diabetes mellitus :

<span class="mw-page-title-main">Diabetes</span> Group of endocrine diseases characterized by high blood sugar levels

Diabetes mellitus, often known simply as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes is due to either the pancreas not producing enough insulin, or the cells of the body becoming unresponsive to the hormone's effects. Classic symptoms include thirst, polyuria, weight loss, and blurred vision. If left untreated, the disease can lead to various health complications, including disorders of the cardiovascular system, eye, kidney, and nerves. Untreated or poorly treated diabetes accounts for approximately 1.5 million deaths every year.

References

  1. Daly ME, Vale C, Walker M, Littlefield A, Alberti KG, Mathers JC (June 1998). "Acute effects on insulin sensitivity and diurnal metabolic profiles of a high-sucrose compared with a high-starch diet" (PDF). The American Journal of Clinical Nutrition. 67 (6): 1186–96. doi: 10.1093/ajcn/67.6.1186 . PMID   9625092.
  2. Thompson, Janice; Manore, Melinda; Sheeshka, Judy (2010), Nutrition a functional approach, Toronto, Ontaria: Pearson Canada, pp. 141–44
  3. Nichols GA, Hillier TA, Brown JB (2007). "Progression From Newly Acquired Impaired Fasting Glusose to Type 2 Diabetes". Diabetes Care. 30 (2): 228–33. doi:10.2337/dc06-1392. PMC   1851903 . PMID   17259486.
  4. Mayo Clinic Diabetes: "Prediabetes". . Accessed Jan. 27, 2009.
  5. . World Health Organization. "Definition, diagnosis and classification of diabetes mellitus and its complications: Report of a WHO Consultation. Part 1. Diagnosis and classification of diabetes mellitus" . Retrieved 2007-05-29.
  6. "Diagnosis and classification of diabetes mellitus". Diabetes Care. 28 Suppl 1: S37–42. 2005. doi:10.2337/diacare.28.suppl_1.s37. PMC   3632174 . PMID   15618111.
  7. "Impaired Fasting Glycemia (IFG) - Impaired Fasting Glucose".