blood glucose data meaningful? pancreas or thyroid?
February 3, 2008 9:49 AM   Subscribe

My husband was recently diagnosed with impaired glucose tolerance. I suspect hyperparathyroidism. I think that his blood glucose does not correlate with the amount of carbohydrate that he eats. My stats knowledge is rusty. What can I do with my Excel spreadsheet to tease any meaning out of this data?

My husband was recently diagnosed with impaired glucose tolerance. He does not have autoimmune antibodies. He has a BMI of 21, he cycles, runs and lifts weights. Although the medical profession has found it most unusual for a person of my husband's physique and antibody status to have this problem, he was simply told to check his blood glucose once each day and come back in 6 months.

He is controlling his blood glucose with diet and exercise only, specifically the Bernstein Diabetes Diet which calls for 30 grams of carbohydrate a day.

I am beginning to suspect that his problems (the impaired glucose tolerance, heartburn, erectile dysfunction, fatigue, memory, concentration, lack of interest in activities) may stem from hyperparathyroidism. Looking back over his bloodwork, his calcium levels are high, but not out of range. He has been to the internist again because of the heartburn and just had another calcium test and a thyroid test done and we are awaiting the results.

To bolster my confidence in this thyroid theory, I have a spreadsheet with 30 dinners. (Clearly we have ignored the endocrinologist's advice re: BG testing. We found his level of "concern" inadequate.)

I think that his blood glucose does not correlate with the amount of carbohydrate that he eats.
For 8 of these meals, he ate only 1 serving of carbohydrate. For 12 of these meals, his BG (blood glucose) fell two hours after eating. 2 of these meals had 1 serving of carb.

For the remaining 18 meals, his BG rose after eating. 6 of these meals had 1 serving of carb.

My stats knowledge is rusty. What can I do with my Excel spreadsheet to tease any meaning out of this data. What sort of graph would help? Help jog my memory please; and spell out what I need to do.
posted by egk to Health & Fitness (17 answers total) 3 users marked this as a favorite
 
I think you need to give specifics or let others see the data because the statement "his BG rose after eating" doesn't mean anything. BG SHOULD rise after eating because the body is taking in fuel. It would also help to see everything he ate, as carbs can come from any number of things.

Not to mention, only having 30 carbs a day sounds extreme and unhealthy. I'm Type II, on the exchange diet for 2,000 calories a day and that includes about 150 carbs.
posted by Brandon Blatcher at 10:08 AM on February 3, 2008


Hyperparathyroidism is not a difficult diagnosis. Ask your doc to get some parathyroid hormone levels.

If, though, as I suspect, you have come to this nutty idea from symptom checklists you found on the Internet, you are making the old error of hearing hoofbeats and expecting zebras. Zebras are rare; horses are common. Hyper-PTH is rare; normocalcemic hyperPTHism is rare as rubies. Impaired glucose tolerance as a manifestation of early diabetes is common as dirt.

Why do you want to play doctor for your husband, anyway? Do you not trust the doc you have? Are you trying to spare him the diagnosis of diabetes? Are you aware that most cases of hyperparathyroidism in someone like your husband will be secondary cases caused by malignant cancers?

Actually, rereading your question, are you aware that the thyroid and parathyroids are two completely separate endocrine systems? It sort of sounds like you don't realize that.
posted by ikkyu2 at 10:12 AM on February 3, 2008


You ignored the endocrinologist's advice, decided to diagnose your husband with hyperparathyroidism despite normal calcium levels, don't understand the difference between the thyroid gland and the parathyroid gland, and you come to the internets as a surrogate.

My advice is good luck to you. The way the body handles carbohydrate is more complex than you think it is and your theory makes no sense. If you really want to test it, have his PTH level checked. Spreadsheets full of data you have no idea yet how to interpret aren't going to be useful to you. Blood glucose will rise with carbohydrate intake to varying degrees throughout the day depending on what else is in the meal, the time of day, the amount of stress the person is in, and other potential factors. Find an endocrinologist that you might actually listen to, and read up heavily on diabetes.
posted by drpynchon at 10:25 AM on February 3, 2008 [1 favorite]


Brandon Blatcher, according to my endocrinologist the Bernstein diet is indeed healthy for those of us who are diabetic and/or insulin resistant. It is indeed extreme, which is why a lot of endos do not promote it - patient compliance is a problem. We've been force-fed the "food pyramid" dogma for so many years that many have trouble believing that a different approach can be healthy.

After my IR diagnosis in 2003, within 3 months on the Bernstein diet I lost 50 pounds, normalized my blood sugars, and brought my cholesterol and triglycerides down into "negative risk factor" levels - all without the use of drugs of any kind. By continuing with a controlled-carb approach, I have maintained these levels ever since.

No meaningful advice to offer the OP, other than my opinion that any endo that promotes Bernstein is very likely keeping up with the latest research, rather than relying on the big-agribusiness dogma promoted by the ADA. You are very lucky to have found one of these rare individuals!
posted by chez shoes at 10:26 AM on February 3, 2008


Those are also the symptoms of the disease we call 'getting old.'
posted by damn dirty ape at 10:29 AM on February 3, 2008


chez shoes, theres a difference between 'healthy' and 'better than the alternative'. Getting only 120 of your daily calories from carbs means you're either getting very low on calories (which seems to have been the case for you, if you lost 50 pounds in 12 weeks ;) ) or making up the difference with protein and fat - which have their own associated health problems.

For a 'normal' person, such a low carb intake would indeed be unhealthy, even Atkins wouldn't recommend such a low carb intake as a long-term plan. For a diabetic person, controlling blood glucose is your most immediate and critical concern.

To the OP: Just wait for the test results. If you're not happy with your doctor, go to a different doctor.
posted by missmagenta at 11:07 AM on February 3, 2008


He is 46.

The endo approved of his choice of the Bernstein diet. This is one thing we liked about this endo, that and he seemed very up to date, for example, he used email to communicate with patients. But he doesn't communicate very well and mainly for that reason we regrettably don't trust him. We are waiting to see a second endo.

We do trust the internist and she has done some sort of thyroid test along with another calcium test. I do not know the details of these tests (serum or ionized calcium for example). And please excuse my sloppiness in referring to the parathyroid as the thyroid. I do realize the difference.

He has not been able to normalize his blood sugars on the Bernstein diet after 10 weeks even though he is not overweight and gets plenty of exercise. Exercise isn't a new habit for him either.

Here is the data:
date dinner before meal after meal # carb servings
1-Jan 91 101 2
2-Jan 109 105 1
4-Jan 92 100 2
5-Jan 85 76 1
6-Jan 109 104 2
13-Jan 111 110 2
15-Jan 96 101 1
17-Jan 105 99 2
18-Jan 104 103 2
19-Jan 99 101 2
20-Jan 95 112 2
21-Jan 103 104 2
22-Jan 100 96 2
23-Jan 102 101 2
24-Jan 101 111 1
25-Jan 102 95 2
26-Jan 98 101 2
27-Jan 105 102 1
29-Jan 102 92 1
7-Dec 109 111 2
9-Dec 109 113 2
10-Dec 103 104 2
11-Dec 98 96 2
12-Dec 92 101 2
16-Dec 91 97 2
20-Dec 101 104 1
21-Dec 89 100 1
25-Dec 101 100 2
29-Dec 108 111 2


Thank you for the input.
posted by egk at 11:27 AM on February 3, 2008


Sorry, I should have specifed that 1 serving is 6 grams of carbohydrate.
posted by egk at 11:40 AM on February 3, 2008


I'm confused. You state that your husband has not been able to regulate his blood glucose levels through diet and exercise alone, yet every one of those pre-meal blood glucose levels you posted are textbook normal (the normal pre-meal range is from 70 mg/dL to 110 mg/dL).

I can't speak to his post-meal levels because I don't know how much time has passed post-meal before you take a sample. A post-meal test should be taken two hours after finishing eating, because there's a predictable rise and fall of blood glucose levels after eating as the body processes its sugar input. Post-meal blood glucose levels are considered abnormal only if the blood glucose level remains above 140 mg/dL two hours after eating. Information collected before that two-hour window has elapsed is relatively useless.
posted by jesourie at 1:40 PM on February 3, 2008


These are 2 hour post meal values.

I agree that his blood sugar levels are "regulated". He thinks they should be lower considering the effort he is putting in. I don't know if that is realistic or not. Maybe it takes more time.

I am just trying to see, statistically, if the amount of carb he eats at a given meal, makes a difference. All things being equal, I would prefer he eat more vegetables.
posted by egk at 2:19 PM on February 3, 2008


egk,

You've now ignored your internist, endocrinologist, and two Metafilter doctors. I agree with ikkyu2, you want to use the Internets as a substitute for your husband's physicians who have gone through medical school and residency training. Do you honestly think that your understanding of physiology ("jog my memory") is better than these trained physicians?

My husband was recently diagnosed with impaired glucose tolerance. He does not have autoimmune antibodies.

Impaired glucose tolerance is generally a precursor of diabetes. Diabetes mellitus. In your husband's case, diabetes mellitus type 2, which has nothing to do with autoimmune antibodies. That's type 1. Type 2 is due to insulin resistance, not due to lack of insulin production (type 1). Diabetes type 2 has a strong genetic pre-disposition.

Looking back over his bloodwork, his calcium levels are high, but not out of range.

They're either high, or within normal limits. Calcium depends on his blood protein levels, his thyroid hormone, his parathyroid hormone, his kidneys--a ton of things.

It's great that you're passionate and involved in your husband's health, but your'e trying to connect things and find correlations that are overly simplistic, as several people have already spelled out. And yes, your blood sugar should rise after a meal.
posted by gramcracker at 2:30 PM on February 3, 2008


The endo approved of his choice of the Bernstein diet. This is one thing we liked about this endo, that and he seemed very up to date, for example, he used email to communicate with patients. But he doesn't communicate very well and mainly for that reason we regrettably don't trust him. We are waiting to see a second endo.

Fair, enough. You're perfectly entitled to find an endocrinologist that can help guide you through these waters. I do give you credit for being willing to stay on top of the blood sugars like this. That's more than most people do. A few points to keep in mind:

1. There are LOTS of thin, athletic looking people who still develop glucose intolerance or type II diabetes. We see it all the time to the point that those of us with a large enough sample size of diabetics know that it's not unusual enough to expect some other endocrine abnormality is at play.

2. You're sticking to a very low carb diet. As you can tell from the above posts, that is a somewhat contentious subject amongst diabetologist. But regardless, one point of common sense is that checking pre- and post-prandial blood sugars becomes less meaningful when you're getting very little carbohydrate in the first place. Think of it this way: for testing purpose, a second diagnostic approach to impaired glucose tolerance is a 2-hr post-prandial glucose test. For this test to be sensitive enough to make a diagnosis, we use 75 grams of glucose. In diabetics, the cut-off is a value of 200. Now look at your husband's post-prandial numbers. Your husband's glucose intolerance is probably quite mild to begin with. By restricting carbs from the diet so drastically, you're making it impossible to really assess his response to carbohydrate challenges. If you want to test his glucose tolerance (or intolerance as it were) you're going to have to give him way more than 8-16 grams of carbs, otherwise all your numbers will essentially look like noise.

This means that perhaps every once in a while, say once a week or every two weeks, consider breaking from the diet for a meal and actually giving him a decent load of sugar to see how he responds. Alternatively, you can follow his Hemoglobin A1c or fructosamine levels which are a surrogate marker of averaged blood sugar over the last few months or weeks respectively. They don't purely correlate with glucose intolerance per se but for your purposes, watching the trends on these may be more helpful than the records you're keeping, especially if you really don't want to ever break from this diet. Alternatively, looking at fasting insulin levels, which some endocrinologists follow, may help gauge how your husband is doing. These are all possibilities to consider if you really want to stick to a low carb diet for purported therapeutic benefits, but want to be able to document if his condition is actually improving.
posted by drpynchon at 4:47 PM on February 3, 2008


a) All of the above.
b) Is he eating when you're not looking?
c) What is the original health issue you are trying to solve? What is his complaint?
posted by gjc at 5:20 PM on February 3, 2008


gramcracker,

We are now following the internist's advice re: BG testing (much less intensive, but more once a day) and I am definitely not trying to ignore any metafilter docs; I was just trying to answer the previous comments.
I have found *all* of this input to be very helpful.

I mentioned the antibodies because he was tested for them. When those test results came back, the 1st endo said (via email):
"antibody test does not shed light on whether or not this is type I or type II. I would not perform any further tests."

Looking back over his bloodwork, his calcium levels are high, but not out of range.
>They're either high, or within normal limits. Calcium depends on his blood protein levels, his thyroid hormone, his parathyroid hormone, his kidneys--a ton of things.

Thank you, that's very helpful information. I now know how to express test results properly, for one thing.


drpynchon,

I found all your points to be very helpful and I appreciate your taking the time to explain them.

gjc,

I doubt he is breaking his diet. That's just not his style.
He originally scheduled his routine check-up and planned to ask the internist about the E.D. At this check-up, the IGT was diagnosed.


We will await the results of the calcium test, the thyroid test and the second endo appt, and I am much better informed, thanks to AskMefi.
posted by egk at 6:06 PM on February 3, 2008


My original question was about whether or not the BG data had any meaning. 40% of the time, his blood glucose fell after eating, I was curious as to whether it mattered how many vegetable servings he ate and if it didn't, what did. This question was answered and I am encouraging him to eat more vegetables.

I was also very curious as to what could cause a "high" calcium test result. That's how I came to learn about hyperparathyroidism. But on AskMefi I learned there is no such thing as a high test result and I now know how to express lab results properly. Looking back over his papers, I see that one of his calcium results was outside of the normal range, which must be why the parathyroid test was done; but the latest calcium results are normal as are the parathyroid hormone results.

They say that the only truly stupid questions are the ones you don't ask. AskMefi certainly doesn't always make you feel that way, but it is a very efficient way to get an education.
posted by egk at 11:47 AM on February 6, 2008


But he doesn't communicate very well and mainly for that reason we regrettably don't trust him. We are waiting to see a second endo.

Sorry to be late to follow up. I wanted to endorse your plan here. I think it's important to have a doc you can communicate with and feel some trust in, if you are going to embark on a regimen of trying to manage and deal with difficult things like impaired glucose tolerance, or anything medical really. So you ought to check out other docs until you find one you like.
posted by ikkyu2 at 11:00 PM on February 27, 2008



The second endo is a much better "fit".

The results: low testosterone. Excuse me, testosterone levels below the normal range for his age group. Cause - Something's not right with the pituitary gland. MRI was clear. Testosterone gel prescribed. Low testosterone can cause insulin resistance, so this could be part of the glucose metabolism problem.
posted by egk at 9:32 AM on April 5, 2008


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