Diagnosing Diabetes

Diagnosing Diabetes2019-02-03T18:47:13+00:00
Diagnosis of diabetes, and even more so of hypoglycemia, can be a tricky task. Single-point blood glucose measurements often miss significant readings, especially for hypoglycemia. While self-diagnosis is not recommended, you can take some steps on your own to aid your health care team in your diagnosis and treatment. These are safe and useful steps. The first step is purely monitoring and not treatment or diagnosis on your part. The other step is good advice from you family physicians.

Who should be tested for diabetes

The ADA (American Diabetes Association) recommends that testing to detect pre-diabetes and type 2 diabetes be considered in adults without symptoms who are overweight or obese and have one or more additional risk factors for diabetes. In those without these risk factors, testing should begin at age 45. The BMI table can be used to find out whether someone is normal weight, overweight, obese, or extremely obese.
People aged 45 or older should consider getting tested for pre-diabetes or diabetes. People younger than 45 should consider testing if they are overweight, obese, or extremely obese and have one or more of the following risk factors:
  • being physically inactive
  • having a parent, brother, or sister with diabetes
  • having a family background that is African American, Alaska Native, American Indian, Asian American, Hispanic/Latino, or Pacific Islander
  • giving birth to a baby weighing more than 9 pounds or being diagnosed with gestational diabetes
  • having high blood pressure—140/90 mmHg or above—or being treated for high blood pressure
  • having an HDL, or “good,” cholesterol level below 35 mg/dL or a triglyceride level above 250 mg/dL
  • having polycystic ovary syndrome, also called PCOS
  • having IFG or IGT on previous testing
  • having a condition called acanthosis nigricans, characterized by a dark, velvety rash around the neck or armpits
  • having a history of cardiovascular disease—disease affecting the heart and blood vessels

Diabetes Diagnosis Tests:

According to CDC (Center for Disease Control), and NDIC (National Diabetes Information Clearinghouse), the following tests are recommended for diagnosis:
  1. Fasting Plasma Glucose (FPG) Test – measures blood glucose in a person who has not eaten anything for at least 8 hours. This test is used to detect diabetes and pre-diabetes.
  2. Oral Glucose Tolerance Test (OGTT) – measures blood glucose after a person fasts at least 8 hours and 2 hours after the person drinks a glucose-containing beverage. This test can be used to diagnose diabetes and pre-diabetes.
  3. Random Plasma Glucose Test – also called a casual plasma glucose test, measures blood glucose without regard to when the person being tested had food. This test, along with an assessment of symptoms, is used to diagnose diabetes but not pre-diabetes.
  4. The A1C Test
  5. The C-Peptide Test

Gluxus' Recommendation:

Gluxus team highly recommends that any or all diabetes test results indicating that a person has diabetes should be confirmed with a second and third test on different days and different times of the day.
FPG Test:
The FPG test is the preferred test for diagnosing diabetes because of its convenience and low cost. However, it will miss some diabetes or pre-diabetes that can be found with the OGTT. The FPG test is most reliable when done in the morning. Results and their meaning are shown in Table 1. People with a fasting glucose level of 100 to 125 milligrams per deciliter (mg/dL) have a form of pre-diabetes called impaired fasting glucose (IFG). Having IFG means a person has an increased risk of developing type 2 diabetes but does not have it yet. A level of 126 mg/dL or above, confirmed by repeating the test on another day, means a person has diabetes.

 

Table 1. FPG test
Plasma Glucose Result (mg/dL) Diagnosis
99 or below Normal
100 to 125 Pre-diabetes
(impaired fasting glucose)
126 or above Diabetes*
Confirmed by repeating the test on a different day.
OGT Test:
Research has shown that the OGTT is more sensitive than the FPG test for diagnosing pre-diabetes, but it is less convenient to administer. The OGTT requires fasting for at least 8 hours before the test. The plasma glucose level is measured immediately before and 2 hours after a person drinks a liquid containing 75 grams of glucose dissolved in water. Results and their meaning are shown in Table 2. If the blood glucose level is between 140 and 199 mg/dL 2 hours after drinking the liquid, the person has a form of pre-diabetes called impaired glucose tolerance (IGT). Having IGT, like having IFG, means a person has an increased risk of developing type 2 diabetes but does not have it yet. A 2-hour glucose level of 200 mg/dL or above, confirmed by repeating the test on another day, means a person has diabetes.
Table 2. OGT Test
2-Hour Plasma Glucose Result (mg/dL) Diagnosis
139 and below Normal
140 to 199 Pre-diabetes
(impaired glucose tolerance)
200 and above Diabetes*
*Confirmed by repeating the test on a different day.
Gestational Diabetes Diagnosis:
Gestational diabetes is also diagnosed based on plasma glucose values measured during the OGTT, preferably by using 100 grams of glucose in liquid for the test. Blood glucose levels are checked four times during the test. If blood glucose levels are above normal at least twice during the test, the woman has gestational diabetes. Table 3 shows the above-normal results for the OGTT for gestational diabetes.Note: Some laboratories may use other numbers for this test.
Table 3. Gestational diabetes: Above-normal results for the OGTT*
When Plasma Glucose Result (mg/dL)
Fasting 95 or higher
At 1 hour 180 or higher
At 2 hours 155 or higher
At 3 hours 140 or higher
*These numbers are for a test using a drink with 100 grams of glucose.
Random Plasma Glucose Test:
A random, or casual, blood glucose level of 200 mg/dL or higher, plus the presence of the following symptoms, can mean a person has diabetes:
  • increased urination
  • increased thirst
  • unexplained weight loss
Other symptoms can include fatigue, blurred vision, increased hunger, and sores that do not heal. The doctor will check the person’s blood glucose level on another day using the FPG test or the OGTT to confirm the diagnosis.
The A1C Test:
The A1C test gives a snapshot of your blood glucose level over the past two to three months. An A1C level of 6.5% or more is consistent with the diagnosis of diabetes. A fasting plasma glucose test is another option. You must not eat for eight hours before the test. A result above 126 is considered diabetes. An oral glucose challenge test with a two-hour blood test may also help your doctor make a diagnosis.
C-Peptide Test:
C-peptide blood levels can indicate whether or not a person is producing insulin and roughly how much. Insulin is initially synthesized in the form of proinsulin. In this form the alpha and beta chains of active insulin are linked by a third polypeptide chain called the connecting peptide, or c-peptide, for short. Because both insulin and c-peptide molecules are secreted, for every molecule of insulin in the blood, there is one of c-peptide. Therefore, levels of c-peptide in the blood can be measured and used as an indicator of insulin production in those cases where exogenous insulin (from injection) is present and mixed with endogenous insulin (that produced by the body) a situation that would make meaningless a measurement of insulin itself. The c-peptide test can also be used to help assess if high blood glucose is due to reduced insulin production or to reduced glucose intake by the cells.
There is little or no c-peptide in blood of type 1 diabetics, and c-peptide levels in type 2 diabetics can be reduced or normal. The concentrations of c-peptide in non-diabetics are on the order of 0.5-3.0 ng/ml.
If results of testing are normal, testing should be repeated at least every 3 years. Doctors may recommend more frequent testing depending on initial results and risk status. People whose test results indicate they have pre-diabetes should have their blood glucose checked again in 1 to 2 years and take steps to prevent type 2 diabetes.
When a woman is pregnant, the doctor will assess her risk for developing gestational diabetes at her first prenatal visit and order testing as needed during the pregnancy. Women who develop gestational diabetes should also have follow-up testing 6 to 12 weeks after the baby is born.
Type 2 diabetes has become more common in children and teens than in the past, and those at high risk for developing diabetes should be tested every 2 years. Testing should begin at age 10 or at puberty, whichever occurs first. Children and teens who are overweight or obese and have other risk factors, such as a family history of diabetes, are at high risk for developing diabetes.

Gluxus Team’s Recommendations:

1) Get a blood glucose meter and start checking your blood glucose before meals and at bedtime. Keep records. Also note what you ate, any exercise and any unusual stress. If you suspect Type-II diabetes, also try to check an hour after eating. If you suspect hypoglycemia, check any time you have suspicious symptoms; you may also want to set up a few runs where you check every 15-30 minutes for up to five hours after eating.

Don’t try to make any adjustments based on the readings until you review them with your doctor — just keep the record and show it to the doctor. This will give the doctor more information than any examination or lab test can give. Furthermore, if you are waiting for an appointment, this record will put you ahead of the game when you actually see the doctor. (If during this monitoring you see a dramatic rise in blood glucose, to preprandial levels of 250 mg/dl

[15 mmol/L] and above, call the doctors and say you need an appointment *now*, not in a month, not next week, and quote your Blood Glucose levels.)

As an additional advantage, doing this monitoring on your own will demonstrate to the doctor that you are willing to put in this kind of effort. Often doctors are reluctant to ask patients to put in serious time to monitor their health because so many patients don’t follow up.

Blood glucose meters and all the supplies are OTC (Over The Counter) items. However, depending on where you live and what type of insurance or national medical coverage you have, you may have to pay from your own pocket if you do not have a prescription or proper pre-authorization. For a month or so of monitoring, this is probably worth the cost.

2) Increase your exercise level, within levels that are safe in light of any other medical conditions. In other words, if you are not already in an exercise program, consult your doctor. Exercise will also help with other stresses you are under. This is primarily applicable if you suspect type 2 diabetes, but may help with hypoglycemia also.

3) Improve your diet if you are not already watching it carefully. A standard diet with moderate calories and fat is good at this stage, until you see the specialist. If you suspect hypoglycemia, you may want to be especially careful of eating large amounts at one time, and avoid concentrated sugars.