Glycated hemoglobin

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Glycated hemoglobin
MedlinePlus 003640
eMedicine 2049478
LOINC 41995-2

Glycated hemoglobin (HbA1c, glycohemoglobin, glycosylated hemoglobin, hemoglobin, A1C or A1c) is a form of hemoglobin (Hb) that is chemically linked to a sugar. Most monosaccharides, including glucose, galactose and fructose, spontaneously (i.e. non-enzymatically) bond with hemoglobin when present in the bloodstream. However, glucose is only 21% as likely to do so as galactose and 13% as likely to do so as fructose, which may explain why glucose is used as the primary metabolic fuel in humans. [1] [2]

Contents

The formation of the sugar-hemoglobin linkage indicates the presence of excessive sugar in the bloodstream, often indicative of diabetes in high concentration (HbA1c >6.4%). [3] A1C is of particular interest because it is easy to detect. The process by which sugars attach to hemoglobin is called glycation and the reference system is based on HbA1c, defined as beta-N-1-deoxy fructosyl hemoglobin as component. [4]

HbA1c is measured primarily to determine the three-month average blood sugar level and can be used as a diagnostic test for diabetes mellitus and as an assessment test for glycemic control in people with diabetes. [5] The test is limited to a three-month average because the average lifespan of a red blood cell is four months or 120 days. Since individual red blood cells have varying lifespans, the test is used as a limited measure of three months. Normal levels of glucose produce a normal amount of glycated hemoglobin. As the average amount of plasma glucose increases, the fraction of glycated hemoglobin increases in a predictable way. In diabetes, higher amounts of glycated hemoglobin, indicating poorer control of blood glucose levels, have been associated with cardiovascular disease, nephropathy, neuropathy, and retinopathy.

Terminology

Glycated hemoglobin is preferred over glycosylated hemoglobin to reflect the correct (non-enzymatic) process. Early literature often used glycosylated as it was unclear which process was involved until further research was performed. The terms are still sometimes used interchangeably in English-language literature. [6]

The naming of HbA1c derives from hemoglobin type A being separated on cation exchange chromatography. The first fraction to separate, probably considered to be pure hemoglobin A, was designated HbA0, and the following fractions were designated HbA1a, HbA1b, and HbA1c, in their order of elution. Improved separation techniques have subsequently led to the isolation of more subfractions. [7]

History

Hemoglobin A1c was first separated from other forms of hemoglobin by Huisman and Meyering in 1958 using a chromatographic column. [8] It was first characterized as a glycoprotein by Bookchin and Gallop in 1968. [9] Its increase in diabetes was first described in 1969 by Samuel Rahbar et al. [10] The reactions leading to its formation were characterized by Bunn and his coworkers in 1975. [11]

The use of hemoglobin A1c for monitoring the degree of control of glucose metabolism in diabetic patients was proposed in 1976 by Anthony Cerami, Ronald Koenig and coworkers. [12]

Damage mechanisms

Glycated hemoglobin causes an increase of highly reactive free radicals inside blood cells, altering the properties of their cell membranes. This leads to blood cell aggregation and increased blood viscosity, which results in impaired blood flow. [13]

Another way glycated hemoglobin causes damage is via inflammation, which results in atherosclerotic plaque (atheroma) formation. Free-radical build-up promotes the excitation of Fe2+-hemoglobin through Fe3+-Hb into abnormal ferryl hemoglobin (Fe4+-Hb). Fe4+ is unstable and reacts with specific amino acids in hemoglobin to regain its Fe3+ oxidation state. Hemoglobin molecules clump together via cross-linking reactions, and these hemoglobin clumps (multimers) promote cell damage and the release of Fe4+-hemoglobin into the matrix of innermost layers (subendothelium) of arteries and veins. This results in increased permeability of interior surface (endothelium) of blood vessels and production of pro-inflammatory monocyte adhesion proteins, which promote macrophage accumulation in blood vessel surfaces, ultimately leading to harmful plaques in these vessels. [13]

Highly glycated Hb-AGEs go through vascular smooth muscle layer and inactivate acetylcholine-induced endothelium-dependent relaxation, possibly through binding to nitric oxide (NO), preventing its normal function. NO is a potent vasodilator and also inhibits formation of plaque-promoting LDL's (sometimes called "bad cholesterol") oxidized form. [13]

This overall degradation of blood cells also releases heme from them. Loose heme can cause oxidation of endothelial and LDL proteins, which results in plaques. [13]

Glycation pathway via Amadori rearrangement (in HbA1c, R is typically N-terminal valine). GlycationViaAmadoriRgmt.svg
Glycation pathway via Amadori rearrangement (in HbA1c, R is typically N-terminal valine).

Principle in medical diagnostics

Glycation of proteins is a frequent occurrence, but in the case of hemoglobin, a nonenzymatic condensation reaction occurs between glucose and the N-end of the beta chain. This reaction produces a Schiff base (R−N=CHR', R = beta chain, CHR' = glucose-derived), which is itself converted to 1-deoxyfructose. This second conversion is an example of an Amadori rearrangement.

When blood glucose levels are high, glucose molecules attach to the hemoglobin in red blood cells. The longer hyperglycemia occurs in blood, the more glucose binds to hemoglobin in the red blood cells and the higher the glycated hemoglobin. [15]

Once a hemoglobin molecule is glycated, it remains that way. A buildup of glycated hemoglobin within the red cell, therefore, reflects the average level of glucose to which the cell has been exposed during its life-cycle. Measuring glycated hemoglobin assesses the effectiveness of therapy by monitoring long-term serum glucose regulation.

A1c is a weighted average of blood glucose levels during the life of the red blood cells (117 days for men and 106 days in women [16] ). Therefore, glucose levels on days nearer to the test contribute substantially more to the level of A1c than the levels in days further from the test. [17]

This is also supported by data from clinical practice showing that HbA1c levels improved significantly after 20 days from start or intensification of glucose-lowering treatment. [18]

Measurement

Several techniques are used to measure hemoglobin A1c. Laboratories may use high-performance liquid chromatography, immunoassay, enzymatic assay, capillary electrophoresis, or boronate affinity chromatography. Point of care (e.g., doctor's office) devices use immunoassay boronate affinity chromatography. [15]

In the United States, HbA1c testing laboratories are certified by the National Glycohemoglobin Standardization Program to standardize them against the results of the 1993 Diabetes Control and Complications Trial (DCCT). [19] An additional percentage scale, Mono S has previously been in use by Sweden and KO500 is in use in Japan. [20] [21]

Switch to IFCC units

The American Diabetes Association, European Association for the Study of Diabetes, and International Diabetes Federation have agreed that, in the future, HbA1c is to be reported in the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) units. [22] IFCC reporting was introduced in Europe except for the UK in 2003; [23] the UK carried out dual reporting from 1 June 2009 [24] until 1 October 2011.

Conversion between DCCT and IFCC is by the following equation: [25]

Interpretation of results

Laboratory results may differ depending on the analytical technique, the age of the subject, and biological variation among individuals. Higher levels of HbA1c are found in people with persistently elevated blood sugar, as in diabetes mellitus. While diabetic patient treatment goals vary, many include a target range of HbA1c values. A diabetic person with good glucose control has an HbA1c level that is close to or within the reference range.[ citation needed ]

The International Diabetes Federation and the American College of Endocrinology recommend HbA1c values below 48 mmol/mol (6.5 DCCT %), while the American Diabetes Association recommends HbA1c be below 53 mmol/mol (7.0 DCCT %) for most patients. [26] Results from large trials in 2008–09 suggested that a target below 53 mmol/mol (7 DCCT %) for older adults with type 2 diabetes may be excessive: Below 53 mmol/mol, the health benefits of reduced A1c become smaller, and the intensive glycemic control required to reach this level leads to an increased rate of dangerous hypoglycemic episodes. [27]

A retrospective study of 47,970 type 2 diabetes patients, aged 50 years and older, found that patients with an HbA1c more than 48 mmol/mol (6.5 DCCT %) had an increased mortality rate, [28] but a later international study contradicted these findings. [29] [30] [31]

A review of the UKPDS, Action to Control Cardiovascular Risk in Diabetes (ACCORD), Advance and Veterans Affairs Diabetes Trials (VADT) estimated that the risks of the main complications of diabetes (diabetic retinopathy, diabetic nephropathy, diabetic neuropathy, and macrovascular disease) decreased by about 3% for every 1 mmol/mol decrease in HbA1c. [32]

However, a trial by ACCORD designed specifically to determine whether reducing HbA1c below 6.0% using increased amounts of medication would reduce the rate of cardiovascular events found higher mortality with this intensive therapy, so much so that the trial was terminated 17 months early. [33]

Practitioners must consider patients' health, their risk of hypoglycemia, and their specific health risks when setting a target HbA1c level. Because patients are responsible for averting or responding to their own hypoglycemic episodes, their input and the doctors' assessments of the patients' self-care skills are also important.

Persistent elevations in blood sugar (and, therefore, HbA1c) increase the risk of long-term vascular complications of diabetes, such as coronary disease, heart attack, stroke, heart failure, kidney failure, blindness, erectile dysfunction, neuropathy (loss of sensation, especially in the feet), gangrene, and gastroparesis (slowed emptying of the stomach). Poor blood glucose control also increases the risk of short-term complications of surgery such as poor wound healing.

All-cause mortality is higher above 8.0% HbA1c as well as below 6.0% in diabetic patients, and above 6% as well as below 5.0% in non-diabetic persons, indicating the risks of hyperglycemia and hypoglycemia, respectively. [34] Similar risk results are seen for cardiovascular disease. [34]

Lower-than-expected levels of HbA1c can be seen in people with shortened red blood cell lifespans, such as with glucose-6-phosphate dehydrogenase deficiency, sickle-cell disease, or any other condition causing premature red blood cell death. Blood donation will result in rapid replacement of lost RBCs with newly formed red blood cells. Since these new RBCs will have only existed for a short period of time, their presence will lead HbA1c to underestimate the actual average levels. There may also be distortions resulting from blood donation during the preceding two months, due to an abnormal synchronization of the age of the RBCs, resulting in an older than normal average blood cell life (resulting in an overestimate of actual average blood glucose levels). Conversely, higher-than-expected levels can be seen in people with a longer red blood cell lifespan, such as with iron deficiency. [35]

Results can be unreliable in many circumstances, for example after blood loss, after surgery, blood transfusions, anemia, or high erythrocyte turnover; in the presence of chronic renal or liver disease; after administration of high-dose vitamin C; or erythropoetin treatment. [36] In general, the reference range (that found in healthy young persons), is about 30–33 mmol/mol (4.9–5.2 DCCT %). [37] The mean HbA1c for diabetics type 1 in Sweden in 2014 was 63 mmol/mol (7.9 DCCT%) and for type 2, 61 mmol/mol (7.7 DCCT%). [38]

The approximate mapping between HbA1c values given in DCCT percentage (%) and eAG (estimated average glucose) measurements is given by the following equation: [36]

eAG(mg/dL) = 28.7 × A1C − 46.7
eAG(mmol/L) = 1.59 × A1C − 2.59
Data in parentheses are 95% confidence intervals
HbA1ceAG
 %mmol/mol [39] mmol/Lmg/dL
5315.4 (4.2–6.7)97 (76–120)
6427.0 (5.5–8.5)126 (100–152)
7538.6 (6.8–10.3)154 (123–185)
86410.2 (8.1–12.1)183 (147–217)
97511.8 (9.4–13.9)212 (170–249)
108613.4 (10.7–15.7)240 (193–282)
119714.9 (12.0–17.5)269 (217–314)
1210816.5 (13.3–19.3)298 (240–347)
1311918.1 (15–21)326 (260–380)
1413019.7 (16–23)355 (290–410)
1514021.3 (17–25)384 (310–440)
1615122.9 (19–26)413 (330–480)
1716224.5 (20–28)441 (460–510)
1817326.1 (21–30)470 (380–540)
1918427.7 (23–32)499 (410–570)

Normal, prediabetic, and diabetic range

The 2010 American Diabetes Association Standards of Medical Care in Diabetes added the HbA1c ≥ 48 mmol/mol (≥6.5 DCCT %) as another criterion for the diagnosis of diabetes. [40]

Diagnostic standard for HbA1c in diabetes [41]
HbA1CDiagnosis
<5.7%Normal
5.7–6.4%Prediabetes
>6.4%Diabetes

Indications and uses

Glycated hemoglobin testing is recommended for both checking the blood sugar control in people who might be prediabetic and monitoring blood sugar control in patients with more elevated levels, termed diabetes mellitus. For a single blood sample, it provides far more revealing information on glycemic behavior than a fasting blood sugar value. However, fasting blood sugar tests are crucial in making treatment decisions. The American Diabetes Association guidelines are similar to others in advising that the glycated hemoglobin test be performed at least twice a year in patients with diabetes who are meeting treatment goals (and who have stable glycemic control) and quarterly in patients with diabetes whose therapy has changed or who are not meeting glycemic goals. [42]

Glycated hemoglobin measurement is not appropriate where a change in diet or treatment has been made within six weeks. Likewise, the test assumes a normal red blood cell aging process and mix of hemoglobin subtypes (predominantly HbA in normal adults). Hence, people with recent blood loss, hemolytic anemia, or genetic differences in the hemoglobin molecule (hemoglobinopathy) such as sickle-cell disease and other conditions, as well as those who have donated blood recently, are not suitable for this test. [43]

Due to glycated hemoglobin's variability (as shown in the table above), additional measures should be checked in patients at or near recommended goals. People with HbA1c values at 64 mmol/mol or less should be provided additional testing to determine whether the HbA1c values are due to averaging out high blood glucose (hyperglycemia) with low blood glucose (hypoglycemia) or the HbA1c is more reflective of an elevated blood glucose that does not vary much throughout the day. Devices such as continuous blood glucose monitoring allow people with diabetes to determine their blood glucose levels on a continuous basis, testing every few minutes. Continuous use of blood glucose monitors is becoming more common, and the devices are covered by many health insurance plans, but not by Medicare in the United States. The supplies tend to be expensive, since the sensors must be changed at least every 2 weeks. Another useful test in determining if HbA1c values are due to wide variations of blood glucose throughout the day is 1,5-anhydroglucitol, also known as GlycoMark. GlycoMark reflects only the times that the person experiences hyperglycemia above 180 mg/dL over a two-week period.[ citation needed ]

Concentrations of hemoglobin A1 (HbA1) are increased, both in diabetic patients and in patients with kidney failure, when measured by ion-exchange chromatography. The thiobarbituric acid method (a chemical method specific for the detection of glycation) shows that patients with kidney failure have values for glycated hemoglobin similar to those observed in normal subjects, suggesting that the high values in these patients are a result of binding of something other than glucose to hemoglobin. [44]

In autoimmune hemolytic anemia, concentrations of HbA1 is undetectable. Administration of prednisolone will allow the HbA1 to be detected. [45] The alternative fructosamine test may be used in these circumstances and it also reflects an average of blood glucose levels over the preceding 2 to 3 weeks.

All the major institutions such as the International Expert Committee Report, drawn from the International Diabetes Federation, the European Association for the Study of Diabetes, and the American Diabetes Association, suggest the HbA1c level of 48 mmol/mol (6.5 DCCT %) as a diagnostic level. [46] The Committee Report further states that, when HbA1c testing cannot be done, the fasting and glucose-tolerance tests be done. Diagnosis of diabetes during pregnancy continues to require fasting and glucose-tolerance measurements for gestational diabetes, and not the glycated hemoglobin.[ citation needed ]

Modification by diet

Meta-analysis has shown probiotics to cause a statistically significant reduction in glycated hemoglobin in type-2 diabetics. [47] Trials with multiple strains of probiotics had statistically significant reductions in glycated hemoglobin, whereas trials with single strains did not. [47]

Standardization and traceability

Hemoglobin A1c is now standardized and traceable to IFCC methods HPLC-CE[ clarification needed ] and HPLC-MS[ clarification needed ].[ citation needed ] The change to the newer unit of mmol/mol is part of this standardization. The standardized test does not test for iodine levels in the blood; hypothyroidism or iodine supplementation are known to artificially raise the A1c. [48] [ unreliable medical source? ] [49]

Veterinary medicine

HbA1c testing has not been found useful in the monitoring during the treatment of cats and dogs with diabetes, and is not generally used; monitoring of fructosamine levels is favoured instead. [50]

See also

Related Research Articles

<span class="mw-page-title-main">Blood glucose monitoring</span> Use of a glucose monitor for testing the concentration of glucose in the blood

Blood glucose monitoring is the use of a glucose meter for testing the concentration of glucose in the blood (glycemia). Particularly important in diabetes management, a blood glucose test is typically performed by piercing the skin to draw blood, then applying the blood to a chemically active disposable 'test-strip'. The other main option is continuous glucose monitoring (CGM). Different manufacturers use different technology, but most systems measure an electrical characteristic and use this to determine the glucose level in the blood. Skin-prick methods measure capillary blood glucose, whereas CGM correlates interstitial fluid glucose level to blood glucose level. Measurements may occur after fasting or at random nonfasting intervals, each of which informs diagnosis or monitoring in different ways.

<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 fasting blood glucose 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 (T2D), 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, fatigue and unexplained weight loss. Symptoms may also include increased hunger, having a sensation of pins and needles, 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.

Drugs used in diabetes treat diabetes mellitus by decreasing the glucose level in the blood. With the exception of insulin, most GLP receptor agonists, and pramlintide, all are administered orally and are thus also called oral hypoglycemic agents or oral antihyperglycemic agents. There are different classes of hypoglycemic drugs, and their selection depends on the nature of diabetes, age, and situation of the person, as well as other factors.

<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.

<span class="mw-page-title-main">Acarbose</span> Chemical compound

Acarbose (INN) is an anti-diabetic drug used to treat diabetes mellitus type 2 and, in some countries, prediabetes. It is a generic sold in Europe and China as Glucobay, in North America as Precose, and in Canada as Prandase.

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

Glycosuria is the excretion of glucose into the urine. Ordinarily, urine contains no glucose because the kidneys are able to reabsorb all of the filtered glucose from the tubular fluid back into the bloodstream. Glycosuria is nearly always caused by elevated blood glucose levels, most commonly due to untreated diabetes mellitus. Rarely, glycosuria is due to an intrinsic problem with glucose reabsorption within the kidneys, producing a condition termed renal glycosuria. Glycosuria leads to excessive water loss into the urine with resultant dehydration, a process called osmotic diuresis.

<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.

Fructosamines are compounds that result from glycation reactions between a sugar and a primary amine, followed by isomerization via the Amadori rearrangement. Biologically, fructosamines are recognized by fructosamine-3-kinase, which may trigger the degradation of advanced glycation end-products. Fructosamine can also refer to the specific compound 1-amino-1-deoxy-D-fructose (isoglucosamine), first synthesized by Nobel laureate Hermann Emil Fischer in 1886.

The polyol pathway is a two-step process that converts glucose to fructose. In this pathway glucose is reduced to sorbitol, which is subsequently oxidized to fructose. It is also called the sorbitol-aldose reductase pathway.

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

Prediabetes is a component of 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.

<span class="mw-page-title-main">Hemoglobin subunit alpha</span> Human hemoglobin protein

Hemoglobin subunit alpha, Hemoglobin, alpha 1, is a hemoglobin protein that in humans is encoded by the HBA1 gene.

The dawn phenomenon, sometimes called the dawn effect, is an observed increase in blood sugar (glucose) levels that takes place in the early-morning, often between 2 a.m. and 8 a.m. First described by Schmidt in 1981 as an increase of blood glucose or insulin demand occurring at dawn, this naturally occurring phenomenon is frequently seen among the general population and is clinically relevant for patients with diabetes as it can affect their medical management. In contrast to Chronic Somogyi rebound, the dawn phenomenon is not associated with nocturnal hypoglycemia.

<span class="mw-page-title-main">Postprandial glucose test</span>

A postprandial glucose (PPG) test is a blood glucose test that determines the amount of glucose, in the plasma after a meal. The diagnosis is typically restricted to postprandial hyperglycemia due to lack of strong evidence of co-relation with a diagnosis of diabetes.

<span class="mw-page-title-main">Remogliflozin etabonate</span> Chemical compound

Remogliflozin etabonate (INN/USAN) is a drug of the gliflozin class for the treatment of non-alcoholic steatohepatitis ("NASH") and type 2 diabetes. Remogliflozin was discovered by the Japanese company Kissei Pharmaceutical and is currently being developed by BHV Pharma, a wholly owned subsidiary of North Carolina, US-based Avolynt, and Glenmark Pharmaceuticals through a collaboration with BHV. In 2002, GlaxoSmithKline (GSK) received a license to use it. From 2002 to 2009, GSK carried out a significant clinical development program for the treatment of type-2 diabetes mellitus in various nations across the world and obesity in the UK. Remogliflozin etabonate's pharmacokinetics, pharmacodynamics, and clinical dose regimens were characterized in 18 Phase I and 2 Phase II investigations. Due to financial concerns, GSK stopped working on remogliflozin and sergliflozin, two further SGLT2 inhibitors that were licensed to the company, in 2009. Remogliflozin was commercially launched first in India by Glenmark in May 2019.

<span class="mw-page-title-main">1,5-Anhydroglucitol</span> Chemical compound

1,5-Anhydroglucitol, also known as 1,5-AG, is a naturally occurring monosaccharide found in nearly all foods. Blood concentrations of 1,5-anhydroglucitol decrease during times of hyperglycemia above 180 mg/dL, and return to normal levels after approximately 2 weeks in the absence of hyperglycemia. As a result, it can be used for people with either type-1 or type-2 diabetes mellitus to identify glycemic variability or a history of high blood glucose even if current glycemic measurements such as hemoglobin A1c (HbA1c) and blood glucose monitoring have near normal values. Despite this possible use and its approval by the FDA, 1,5-AG tests are rarely ordered. There is some data suggesting that 1,5-AG values are useful to fill the gap and offer complementary information to HbA1c and fructosamine tests.

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.

<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.

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