Dr. Ritamarie's Additional Key Lab Tests

The A1c test evaluates the average amount of glucose in the blood over the last 2 to 3 months. It does this by measuring the concentration of glycated (also often called glycosylated) hemoglobin A1c. Hemoglobin is an oxygen-transporting protein found inside red blood cells (RBCs). There are several types of normal hemoglobin, but the predominant form – about 95-98% – is hemoglobin A. As glucose circulates in the blood, some of it spontaneously binds to hemoglobin A. The hemoglobin molecules with attached glucose are called glycated hemoglobin. The higher the concentration of glucose in the blood, the more glycated hemoglobin is formed. Once the glucose binds to the hemoglobin, it remains there for the life of the red blood cell – normally about 120 days. The predominant form of glycated hemoglobin is referred to as HbA1c or A1c. A1c is produced on a daily basis and slowly cleared from the blood as older RBCs die and younger RBCs (with non-glycated hemoglobin) take their place. This test is used to monitor treatment in someone who has been diagnosed with diabetes. It helps to evaluate how well their glucose levels have been controlled by treatment over time. This test may be used to screen for and diagnose diabetes or risk of developing diabetes. In 2010, clinical practice guidelines from the American Diabetes Association (ADA) stated that A1c may be added to fasting plasma glucose (FPG) and oral glucose tolerance test (OGTT) as an option for diabetes screening and diagnosis. For monitoring purposes, an A1c of less than 7% indicates good glucose control and a lower risk of diabetic complications for the majority of diabetics. However, in 2012, the ADA and the European Association for the Study of Diabetes (EASD) issued a position statement recommending that the management of glucose control in type 2 diabetes be more "patient-centered." Data from recent studies have shown that low blood sugar (hypoglycemia) can cause complications and that people with risk of severe hypoglycemia, underlying health conditions, complications, and a limited life expectancy do not necessarily benefit from having a stringent goal of less than 7% for their A1c. The statement recommends that people work closely with their doctor to select a goal that reflects each person's individual health status and that balances risks and benefits.

A high-sensitivity CRP (hs-CRP) test may be used by itself, in combination with other cardiac risk markers, or in combination with a lipoprotein-associated phospholipase A2 (Lp-PLA2) test that evaluates vascular inflammation. The hs-CRP test accurately detects low concentrations of C-reactive protein to help predict a healthy person's risk of cardiovascular disease (CVD). High-sensitivity CRP is promoted by some as a test for determining a person's risk level for CVD, heart attacks, and strokes. The current thinking is that hs-CRP can play a role in the evaluation process before a person develops one of these health problems.

Insulin is a hormone that is produced and stored in the beta cells of the pancreas. It is vital for the transportation and storage of glucose at the cellular level, helps regulate blood glucose levels, and has a role in lipid metabolism. When blood glucose levels rise after a meal, insulin is released to allow glucose to move into tissue cells, especially muscle and adipose (fat) cells, where is it is used for energy production. Insulin then prompts the liver to either store the remaining excess blood glucose as glycogen for short-term energy storage and/or to use it to produce fatty acids. The fatty acids are eventually used by adipose tissue to synthesize triglycerides to form the basis of a longer term, more concentrated form of energy storage. Without insulin, glucose cannot reach most of the body's cells. Without glucose, the cells starve and blood glucose levels rise to unhealthy levels. This can cause disturbances in normal metabolic processes that result in various disorders, including kidney disease, cardiovascular disease, and vision and neurological problems. Thus, diabetes, a disorder associated with decreased insulin effects, is eventually a life-threatening condition.

Cholesterol is a waxy, fat-like substance that occurs naturally in all parts of the body. Your body needs some cholesterol to work properly. But if you have too much in your blood, it can combine with other substances in the blood and stick to the walls of your arteries. This is called plaque. Plaque can narrow your arteries or even block them. High levels of cholesterol in the blood can increase your risk of heart disease. Your cholesterol levels tend to rise as you get older. There are usually no signs or symptoms that you have high blood cholesterol, but it can be detected with a blood test. You are likely to have high cholesterol if members of your family have it, if you are overweight or if you eat a lot of fatty foods. You can lower your cholesterol by exercising more and eating more fruits and vegetables. You also may need to take medicine to lower your cholesterol.

Triglycerides are a form of fat and a major source of energy for the body. This test measures the amount of triglycerides in the blood. Most triglycerides are found in fat (adipose) tissue, but some triglycerides circulate in the blood to provide fuel for muscles to work. After a person eats, an increased level of triglycerides is found in the blood as the body converts the energy not needed right away into fat. Triglycerides move via the blood from the gut to adipose tissue for storage. In between meals, triglycerides are released from fat tissue to be used as an energy source for the body. Most triglycerides are carried in the blood by lipoproteins called very low density lipoproteins (VLDL). High levels of triglycerides in the blood are associated with an increased risk of developing cardiovascular disease (CVD), although the reason for this is not well understood. Certain factors can contribute to high triglyceride levels and to risk of CVD, including lack of exercise, being overweight, smoking cigarettes, consuming excess alcohol, and medical conditions such as diabetes and kidney disease.

Vitamin D2 ((ergocalciferol,) is found in fortified foods and in most vitamin preparations and supplements. Vitamin D comes from two sources: endogenous, which is produced in the skin on exposure to sunlight, and exogenous, which is ingested in foods and supplements. The D2 form is found in fortified foods and in most vitamin preparations and supplements. Vitamin D2 is effective when it is converted by the liver and the kidney into the active form, 1,25-dihydroxyvitamin D.

Vitamin D3 (cholecalcifero) which comes from animals. Vitamin D comes from two sources: endogenous, which is produced in the skin on exposure to sunlight, and exogenous, which is ingested in foods and supplements. Vitamin D3 is the form produced in the body and is also used in some supplements. Vitamin D3 are is converted by the liver and the kidney into the active form, 1,25-dihydroxyvitamin D.

Vitamin D comes from two sources: endogenous, which is produced in the skin on exposure to sunlight, and exogenous, which is ingested in foods and supplements. The chemical structures of the types of vitamin D are slightly different, and they are named vitamin D2 (ergocalciferol, which comes from plants) and vitamin D3 (cholecalciferol, which comes from animals). The D2 form is found in fortified foods and in most vitamin preparations and supplements. Vitamin D3 is the form produced in the body and is also used in some supplements. Vitamin D2 and D3 are equally effective when they are converted by the liver and the kidney into the active form, 1,25-dihydroxyvitamin D.

Vitamin D comes from two sources: endogenous, which is produced in the skin on exposure to sunlight, and exogenous, which is ingested in foods and supplements. The chemical structures of the types of vitamin D are slightly different, and they are named vitamin D2 (ergocalciferol, which comes from plants) and vitamin D3 (cholecalciferol, which comes from animals). The D2 form is found in fortified foods and in most vitamin preparations and supplements. Vitamin D3 is the form produced in the body and is also used in some supplements. Vitamin D2 and D3 are equally effective when they are converted by the liver and the kidney into the active form, 1,25-dihydroxyvitamin D.