Is fasting blood sugar the only basis for diagnosis?

Back in March, I went to Urgent care for an infection, and my BS was 271. The Urgent care doctor told me to see my primary right away because I probably have diabetes. My primary had me do some labs, and my FBS was 118. She said I don’t have diabetes because my fbs was below 125 but I probably had prediabetes. A couple months later, my mom, who just found out she’s type 2 earlier this year, checked my BS just to test her meter. My BS was 251. I knew then I must have diabetes, as I no longer had an infection as an “excuse” for the high number.

Yesterday, I went to see my doctor again for a routine physical. I asked her what my A1c had been back in March. She told me 6.8. Shouldn’t that have been enough to diagnose me then? She had me do labs again today but not with a GTT. I’m now wondering, since I’ve been monitoring my BS - mostly keeping it below 130, with fbs usually below 100 - will she still not think I have diabetes? I really want a prescription for test strips, as I’ve been paying for them myself!

Sadly, many doctors are too lax about accepting not normal BG as ok.

Normal fasting is under 100 & non-diabetics don’t have 271, infection or no infection. Yes, she should have diagnosed you with an A1c of 6.8, which is an average BG of 149. It is probably higher now, sorry to say, if you’ve got numbers around 250 frequently.

To answer your question, fasting BG is not the only basis for diagnosis–you’re right. There are people with perfectly normal fasting BG who soar after meals & why GTT should be done. Other tests you should ask for are a thyroid panel, C-peptide (measures how much insulin your pancreas is producing) & GAD antibody test (measures if your pancreas is under attack). Staggering how many get misdiagnosed because doctors assume someone is a Type 2 & don’t get proper treatment.

Ask your doctor for a referral to an endo. If she refuses, get another doctor. Your health is in your hands, not hers.

Insist on an Rx for strips & ask her for a meter since it will come with strips. They get freebies from the pharm reps.

A good source for information about proper diagnosis of diabetes is the guidelines published by the American Association of Clinical Endochronologists ( According to them (and they are supposed to be the “experts”), a random BS over 200 indicates diabetes. Unfortunately, most general practictioners are poorly trained. The AACE says you have diabetes if your fasting > 126 mg/dl or your 2 hour BS after 75 g of carbs > 200 mg/dl or you have a random BS test > 200 mg/dl. While the AACE does not recommend using HbA1c to diagnose diabetes, it does recommend that patients keep their HbA1c < 6.5%.

You are totally right, you do have diabetes and you should be concerned.

I went for years with diabetes until my fasting eventually gave out. I am convinced that some of my problems like carpal tunnel syndrome and neuropathy were caused by sloppy diagnosis. I’m still just a bit angry about it.

I would urge you consider your urgent care diagnosis to have been totally correct and either get a new more competent doctor or a referral to an endo.

At the American Diabetes Scientific Sessions in June 2009, there was a presentation about using A1C to diagnose diabetes. Over 6.5% is diabetes.
Over 6% is “elevated blood glucose,” which some call pre-diabetes.

The standard for care for a person newly diagnosed with diabetes type 2 is immediately to put that person on metformin plus modify eating and add more physical activity.

If your doctor doesn’t follow current standards of care, it’s time to start doctor shopping! Best wishes.

Thanks, Gerri, bsc, and Kelly for the replies. I think I’m just a bit disappointed at my doctor for having been so lax with my diagnosis. I basically diagnosed myself, then told her about it at my last visit.

Gerri, I’m hoping my A1c is not over 7. Since May, I’ve read many books, including Dr. Bernstein’s Diabetes Solution. And although I don’t follow his diet completely, I’ve been eating pretty low carb and keeping active. I’ve also been checking my BG ~6 times a day, making sure that if I have anything above 130, I exercise to lower it.

I will take your advice and get a referral for an endo; thanks! I’ll probably start looking for another primary, too. I hope that doctors get better with diagnosis since diabetes is such a serious condition. My mom has a similar story, except her doctor waited 2 years before telling her. So sad.

Good for you! Staying active is one piece of the diabetes control puzzle that so many people unfortunately skip. I hope you find some health care providers you can trust. And, if your body needs it, blood glucose-lowering medication.

Although staying off meds is a desire for many people diagnosed with type 2, the important thing is to get the A1C number in the target range–as well as make sure blood pressure and blood lipids are in range. All those things together help prevent, delay, and minimize complications. We’ll be glad to hear how it goes for you.