repeatedly elevated fasting glucose

Medical Q&A [Moderated]
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As I wait for the BBM Medical Service to launch, I caved and tried a DTC lab company. I live in a healthcare worker shortage area, so this was the easiest way to get labs I wanted as I approach 40 (like ApoB). I’m also a doc and don’t stress about the false positives and incidentalomas, so when the price dropped during a sale, I went for it.

My question is regarding fasting glucose. It resulted 103, which is about what it’s been on two prior BMPs (both times when I had established with a new PCP - both times probably not indicated). I thought Austin mentioned also having a fasting glucose higher than he’d like, so I wonder if there’s anything I should be thinking about.

More context:

  • A1c 5.3%, TG 48, and ALT 11

  • LDL and HDL both 72.

  • insulin was 3.6 and leptin low :joy: (ok now you know what company I used)

  • waist circumference upper 20s in.

  • I follow BBM so yes I’m hitting the physical activity guidelines and protein/fiber goals

  • no family history of DM2

  • BPs always low-normal

  • average about 200g carbs daily at 59kg bw

I’m sure you’ll say I should get a CGM (jk), but really, any further advice, or just a shoulder shrug?

ps: Unfortunately this was my first time getting a ferritin checked, and it was hella low (no anemia). I just wanna give Austin a shoutout for raising awareness about the higher prevalence of iron deficiency in my demographic and advocating for more screening. I’m sure that when I mentioned being “tired” to any doc they just figured it was medical training.

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Hey! Totally understand the thought process here.

As I’m sure you know, glucose is super variable for all sorts of reasons. So, while it can be diagnostic on its own in extreme ranges (like the established “>200 mg/dL” criterion for diabetes), in your more “intermediate”/indeterminate range, it’s useful to look at other metrics to see whether there’s additional signal to fine-tune our post-test probability of dysglycemia or insulin resistance. So:

Your waist measurement and blood pressure are in a healthy range.

The A1c of 5.3% argues against it.

Triglycerides of 48 strongly argue against insulin resistance (you can further calculate a Triglyceride-Glucose index, which is a pretty good biomarker of IR, and yours is good).

The LDL-c and HDL-c are both in a great range, without the atherogenic dyslipidemia we see associated with hyperglycemia & IR. Technically you may even be able to calculate an LPIR score based on other data provided to you, if you really wanted to nerd out on this … but not necessary here, IMO.

Fasting insulin of 3.6 is well below the range that would raise concern for IR.

So yes, this gets a shoulder shrug from me. We also know that highly physically active individuals can also have benign elevations in glucose & even A1c as an adaptive mechanism, and is not necessarily pathological or associated with the usual complications. You sound to be in great shape from this metabolic standpoint!

And I’m really glad to hear regarding the ferritin getting caught. I really push for this among my trainees & colleagues, and additionally learning what the proper references ranges and therapeutic targets ought to be (imo, >50 ng/mL for most). You didn’t mention whether you have overt anemia, but note that iron deficiency can lead to prolonged RBC lifespan, which can falsely elevate HbA1c levels - so your true A1c may be even lower than 5.3%.

And yeah … about that leptin :roll_eyes: :rofl:

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