Once in 3 months
What Does it do?
A laboratory test known as HbA1c or “glycosylated hemoglobin” should be obtained once in 3 months. HbA1c measures the average glucose concentration in blood over the preceding 3 months. The higher the glucose levels over previous 90 days, the higher will be the HbA1c. Therefore, HbA1c is a useful indicator of how well blood glucose has been controlled in the recent past. HbA1c test does not show daily fluctuations in the blood glucose concentration; for this one needs to check blood glucose at home 6-10 times a day using a blood glucose meter and / or a continuous glucose monitoring (CGM) device. A good HbA1c could that results from an average of very high and very low values is not acceptable. Therefore, one should aim for a good HbA1c without major fluctuations in blood glucose.
How to prepare for the test?
This test can be done at any time of the day and no fasting is required.
A HbA1c below 5.7% would be found in those without diabetes.
Persons with type 1 diabetes should aim for a HbA1c of 7% or less.
Corrective action is needed if your HbA1c is over 7.5%.
Soon after diagnosis of Type 1 Diabetes (T1D), a blood test for anti-thyroid antibodies would be obtained. About 10-20% of individuals with T1DM would have disordered thyroid function at the time of diagnosis or may develop it later as thyroid disease and T1D are both autoimmune diseases. A positive antibody test indicates a higher likelihood of thyroid dysfunction but does not confirm it’s presence. To evaluate thyroid function, another blood test (TSH, FT4 and FT3) is done at the outset (but only after ketones have cleared and blood glucose has stabilised), and if normal then this test is repeated every 2 years or whenever the individual develops certain symptoms (weight gain despite reduced appetite, feeling unusually dull or sleepy, lowered tolerance for cold, frequent unexplained hypoglycaemia).
Blood lipid profile is done at the onset of diabetes (after ketones have cleared and blood glucose is stable) and if normal, the test is repeated once in 3 years (if abnormal then treatment is initiated and the test is repeated annually). A high level of LDL cholesterol or triglycerides may be due to poor diabetes control or it could be a familial feature. The first step in management of abnormal lipids is to ensure good diabetes control, including healthy eating, a low fat diet entailing reduction of saturated fat intake and regular aerobic physical activity. If the LDL cholesterol remains above 130 or 160 mg% then certain medications may be needed.
A first morning urine sample is tested for albumin to creatinine ratio once a year after 2 years of diabetes onset (or 5 years of diabetes onset in patients below the age of 11 years). An abnormal result needs to be confirmed by repeating the test on 2 more occasions. Persistent “microalbuminuria” is an early sign of kidney dysfunction due to diabetes. Fortunately this is a reversible phase and if detected on time then tight control of diabetes, reduction in protein intake in diet and addition of a medication (ACE inhibitor) can revert it to normal. This underlines the importance of regular screening for albuminuria.
A small number of individuals with T1D may develop gluten sensitivity / celiac disease as this is also an autoimmune disease (like T1D). Some with celiac disease may have symptoms such as abdominal pain, loose stools or constipation, pallor, failure to grow in height, recurrent mouth ulcers. Many others may have no symptoms, hence a screening test is recommended at the time of diagnosis and then 2-3 years after diagnosis or if one develops the symptoms mentioned here. The blood test for celiac disease is known as “tissue transglutaminase IgA antibody test. A positive test does not confirm the diagnosis of celiac disease. If the test is positive, an intestinal biopsy is essential to prove the diagnosis. Once the diagnosis is made with certainty the treatment for celiac disease is complete elimination of all sources of gluten from the diet but this has to be observed throughout life. There is no medicine for treating celiac disease. One in 500 persons have a hereditary condition known as serum IgA deficiency and in them the routine blood test for celiac disease may not be of help; the IgG antibody level is tested in place of the IgA antibody.