Weight, what now?

Ring ring!
Hello?
Hi, this is [person] from [your PCP's] office.
Hi. 
I'm here to help you schedule an appointment with our nutritionist.
Why?
Because your test results came back and you're pre-diabetic.
...
...
...
WHAT?
expurgated version: Oh, this was a surprise? - why yes it is. This is the first I've heard of it. Would you like to speak to Dr. G? Hell yes.

So the deal is that with no indication of what my base-line is, just on the chart on the wall and one glucose test, my BMI/weight/age, I have a "25% chance of getting diabetes within 5-ish years, if I do nothing with my weight." 
Despite the fact that I weigh 10 lbs less than I did last year
That he doesn't know my medical history as it has been written from a hole in the wall, as they have not yet been transferred. 
That my overweight family members have to date not gotten Diabetes
And WTF- I'm not that heavy. I would be curious to know what resource he's using to determine this outcome. 

My answer to Dr. G was that it's the most stressful year of my life. I am not remotely concerned about this outcome at this time. I do not have the luxury of doing a lot of the things I'd like to do right now, but that this will change really and for true when some factors out of my control are different. But for now, it's just not going to happen. It is what it is and I think I'm doing quite well under the circumstances. Next year. We'll see. After he knows me and my charts better.

(but really... what does he think I should weigh? If it's the fucking BMI.... well, we need to have words. )

ETA: From the Doctor since I wrote last...

"In regards to BMI, I completely agree that it is not a very accurate determination of healthy weight but a rough tool that should prompt us to take a more comprehensive look into health/fitness. I look forward to getting toknow you more as a patient and a person. Regards, Dr. G"  

So, he still hasn't addressed the issue of what caused him to make this deduction. I've emailed back with the request he elaborate. If it's weight, what does he feel would be a safer weight. If something else, what. If a combination, what. We shall see. I'm feeling somewhat mollified after he agreed about BMI, but his first impression is radically marred. I will not be blindly following his suggestions, but then again it's not a good idea to do so anyway.

ETA 2: " Hemoglobin A1C is slightly elevated. A level between 5.7-6.4%" ... OK. So it's that.