Diabetes and Glycated Hemoglobin Monitoring
Diabetes and Glycated Hemoglobin Monitoring
Diabetes Mellitus is one of the commonest non communicable diseases in the world currently associated with increased morbidity and mortality. It is a condition characterized by persistent hyperglycemia in the body due to either insulin deficiency or insulin resistance. These have broadly led to the classification of diabetes as either type one or type two diabetes mellitus. Type one diabetes mellitus is characterized by insulin deficiency, whereby the pancreatic cells are not able to produce sufficient insulin to drive the consumed glucose into the cells, thus creating a state of hyperglycemia. It is mainly an inherited disorder and thus mainly seen in children and young adolescents (Longo, Harrisonv & Kasper, 2011).
Type two diabetes mellitus is characterized by resistance to insulin. In this case, the cells of the body are not responsive to insulin and therefore in as much as there is sufficient insulin, the cells do not respond to the insulin hormone. This ultimately leads to hyperglycemia. A prolonged state of hyperglycemia is detrimental to the body and causes either macrovascular complications in the body such as cerebral vascular accidents (CVA) or microvascular complications such as diabetic retinopathy in the eyes which are potentially disabling. These among many others are the reasons as to why the diagnosis and intervention to counter diabetes are very important (Longo, Harrison & Kasper, 2011).
According to the American Diabetic Association (ADA), one is said to have diabetes mellitus if they have a fasting blood glucose of more than 7.0mmol/l (126mg/dl) or if following an oral glucose tolerance test, 2hours later one still has a glucose level of above 11.1mmol/l(200mg/dl) or if an individual has a random blood glucose level of more than 11.1mmol/l. The latest criterion added by the ADA was conducted using the glycated hemoglobin levels (HbA1C). It states that if a patient presents with an initial HbA1C of above 6.5 % (48mmol/mol), then the individual is said to have diabetes. This is the focus of our discussion in this assignment. (American Diabetes Association, 2014)
The research of interest had the topic of Hemoglobin A1C as a new diagnostic tool for diabetes screening and new onset diabetes prediction. It was a six year community based prospective study whose main objective was to evaluate the usefulness of HbA1C levels when screening for undiagnosed diabetes and as a predictor of 6-year incident diabetes. It was also a prospective, population based cohort study. The research had 10,038 participants who underwent an OGTT protocol test at baseline and at each biennial follow up to identify their initial glycemic state. At the beginning, it was realized that 6.8% of the participants had undiagnosed diabetes. At 6years, 10.2% of the participants had developed incident diabetes .Following multivariate adjustment, it was predicted that men with baseline A1C of more than 5.6% had a 2.4 fold increased risk and women had a 3.1 fold increased risk of new onset diabetes at the same baseline levels (Sung Hee, Tae, Lim . et al, 2011).
Glycated Hemoglobin is one of the latest diagnostic tools used in the intervention and management of Diabetes Mellitus. Grossly, it measures the amount of hemoglobin that is combined with glucose in the blood in the preceding periods before the test of about eight to twelve weeks. By so doing, it measures how well the glucose levels in the body are well controlled and how much damage has been done to the body by the persistent state of hyperglycemia. The higher the HbA1C levels, the higher the risk of microvascular and microvascular complications such as cardiovascular diseases, diabetic nephropathy, diabetic neuropathy and retinopathy. The test should however be performed in a quality assured lab in which strict assurance tests are in place with standardized assays with criteria aligned to the international values to ensure accuracy of the measurements. (Sung Hee, Tae, Lim S. et al, 2011)
HbA1C is formed in the blood by a non-enzymatic glycation pathway following exposure of hemoglobin to plasma glucose. The average lifespan of a red blood cell in the body is approximately three months. This thus explains why the test measures the amount of glycation in the previous two to three months prior to the test. If a patient has normal levels of glucose, there will be normal glycation of hemoglobin. However, if the glucose levels rise, then the amount of glycated hemoglobin also rises. Once glycation occurs, the hemoglobin molecule persists in that manner until it undergoes senile degradation at 120 days. Therefore, an accumulation of glycated hemoglobin within the erythrocyte shows the average level of glucose that the entire cell was exposed to during its entire lifecycle (Longo, Harrison & Kasper, 2011).
This test is therefore able to identify whether a patient’s diabetes is well controlled or poorly controlled, and thus measures can be put in place to ensure a good control. This may involve alteration of medication, increase in dosage of the current medication, or even advise on the importance of compliance in medication if that is the main problem. These patients can also undergo nutritional counseling to know how much sugar intake they are allowed to use and the specific kinds of food to eat or not to eat. By so doing, a patient is prevented from developing complications that could be avoided (Sung, Tae, Lim S. et al, 2011).
The complications of DM are generally very difficult to manage and if a preventive mechanism is feasible, then this should be the way to go. Most of the mortalities and morbidities seen in diabetes mellitus are often due to the complications due to the disease and not the disease itself. The progression of DM is also often subtle and silent and one can never know how bad their glucose state is only by use of the random and fasting blood glucose levels (Longo, Harrison & Kasper, 2011).
HbA1C levels can also be used to indicate people with prediabetic states. When a non-diabetic patient has levels of between 6.0 % and 6.4 % (42-47mmol/mol), they are said to be prediabetic. Such individuals can therefore begin supportive measures so as to delay or even prevent progression to a state of diabetes. They can be put on nutritional counseling and be taught on how to adjust their diet, what to eat and what to minimize the progression of the condition or even stop the progression itself. The levels can also be monitored in type one diabetic patients to evaluate their glycemic control and to determine whether stringent mechanism can be added in place to manage them better and prevent complications in a similar fashion (Colledge R., Walker R., Ralston H., 2010).
American Diabetes Association, 2014, Standards of medical care in diabetes. Diabetes Care 34:S14
Colledge R., Walker R., Ralston H., 2010, Davidson’s Principles and Practice of Medicine. Elsevier.
Longo L., Harrison T. R., D. L. Kasper, 2011, Harrison’s Principles of Internal Medicine McGraw-Hill Medical.
Sung Hee C. ,Tae H.K, Lim S. et al, 2011, Hemoglobin A1C as a diagnostic tool for Diabetic screening and New Onset Diabetes Prediction, Health services research.