Comments on: Blind Men and The Diabetes Elephant http://www.docgurley.com/2008/06/14/blind-men-and-the-diabetes-elephant/ Posts from an Insane Healthcare System Wed, 25 Jan 2012 07:17:58 +0000 hourly 1 By: Liana http://www.docgurley.com/2008/06/14/blind-men-and-the-diabetes-elephant/#comment-1056 Liana Fri, 20 Jun 2008 16:38:59 +0000 http://www.docgurley.com/?p=204#comment-1056 Thanks, Doc. In our health region, we get told off for ordering HbA1c for diagnosis... so I use it to monitor treatment, and also to decide when to start right away with meds instead of giving a 3 month trial of exercise and lifestyle. Maybe with this new study, they'll reconsider? I agree that the HbA1c is a lot easier... no fasting required. However, in the Canadian Diabetes clinical practice guidelines, they say that the lack of standardization with the HbA1c test makes it less useful for diagnosis, and they also mention that a FPG of 7.0 or OGTT of >/=11.1 are most predictive of microvascular damage (alas, no mention of macrovascular damage). Of course, the guidelines are from 2003 and updated guidelines are going to be released in the fall so who knows if they will change their tune? I'm eager to see what changes they recommend. Thanks, Doc.

In our health region, we get told off for ordering HbA1c for diagnosis… so I use it to monitor treatment, and also to decide when to start right away with meds instead of giving a 3 month trial of exercise and lifestyle. Maybe with this new study, they’ll reconsider?

I agree that the HbA1c is a lot easier… no fasting required. However, in the Canadian Diabetes clinical practice guidelines, they say that the lack of standardization with the HbA1c test makes it less useful for diagnosis, and they also mention that a FPG of 7.0 or OGTT of >/=11.1 are most predictive of microvascular damage (alas, no mention of macrovascular damage).

Of course, the guidelines are from 2003 and updated guidelines are going to be released in the fall so who knows if they will change their tune? I’m eager to see what changes they recommend.

]]> By: Doc Gurley http://www.docgurley.com/2008/06/14/blind-men-and-the-diabetes-elephant/#comment-1046 Doc Gurley Tue, 17 Jun 2008 23:24:48 +0000 http://www.docgurley.com/?p=204#comment-1046 The HgbA1C study was specifically designed to look at non-diabetics, but included some diabetics anyways. The authors state that in prior studies with diabetics "A1C levels have also been associated with mortality in patients with type 1 diabetes and nondiabetic chronic kidney disease and with incident cardiovascular disease." Of the 408 diabetics in this study, "Although mortality rate was also increased in participants with a previous diagnosis of diabetes, this was only partially explained by their increased A1C levels." - possibly due to smaller numbers. My Doc Gurley take on this question is that elevated HgbA1C is bad for everyone, but sneakier and previously-unrecognized as potentially lethal in non-diabetics. To answer your final question, the HgbA1C test is unique in that it is 1) much easier to do than either a 2 hour OGGT or fasting glucose (as this study proves, where HgbA1C was done as part of a hepatitis screening campaign) and 2) has unique properties in that it looks for elevated blood glucose levels averaged over the preceding three months. All other glucose tests just look at your blood "now" but don't say anything about your blood sugar over time. "Better" is a relative measure of a test- and in this case HgbA1C's much, much better at picking up what your body has been exposed to for the last three months. The HgbA1C study was specifically designed to look at non-diabetics, but included some diabetics anyways. The authors state that in prior studies with diabetics “A1C levels have also been associated with mortality in patients with type 1 diabetes and nondiabetic chronic kidney disease and with incident cardiovascular disease.” Of the 408 diabetics in this study, “Although mortality rate was also increased in participants with a previous diagnosis of diabetes, this was only partially explained by their increased A1C levels.” – possibly due to smaller numbers. My Doc Gurley take on this question is that elevated HgbA1C is bad for everyone, but sneakier and previously-unrecognized as potentially lethal in non-diabetics. To answer your final question, the HgbA1C test is unique in that it is 1) much easier to do than either a 2 hour OGGT or fasting glucose (as this study proves, where HgbA1C was done as part of a hepatitis screening campaign) and 2) has unique properties in that it looks for elevated blood glucose levels averaged over the preceding three months. All other glucose tests just look at your blood “now” but don’t say anything about your blood sugar over time. “Better” is a relative measure of a test- and in this case HgbA1C’s much, much better at picking up what your body has been exposed to for the last three months.

]]> By: Liana http://www.docgurley.com/2008/06/14/blind-men-and-the-diabetes-elephant/#comment-1045 Liana Tue, 17 Jun 2008 22:32:15 +0000 http://www.docgurley.com/?p=204#comment-1045 Hmm... interesting. I read the study, and what I got out of it was more so that a lot of people are running around out there with undiagnosed diabetes, and undiagnosed diabetes will kill you. Of note, 71% of the participants were Maori. Significantly more at risk of diabetes and metabolic syndrome than Caucasians for example. So it's not really clear to me how well this would apply to Caucasians since they weren't able to tease out other cardiovascular risk factors. Are there any studies that suggest that a HbA1c is better than, say, a 2 hour OGTT or fasting plasma glucose for diagnosing diabetes? Hmm… interesting. I read the study, and what I got out of it was more so that a lot of people are running around out there with undiagnosed diabetes, and undiagnosed diabetes will kill you.

Of note, 71% of the participants were Maori. Significantly more at risk of diabetes and metabolic syndrome than Caucasians for example. So it’s not really clear to me how well this would apply to Caucasians since they weren’t able to tease out other cardiovascular risk factors.

Are there any studies that suggest that a HbA1c is better than, say, a 2 hour OGTT or fasting plasma glucose for diagnosing diabetes?

]]> By: Michael Maison http://www.docgurley.com/2008/06/14/blind-men-and-the-diabetes-elephant/#comment-1044 Michael Maison Tue, 17 Jun 2008 02:52:30 +0000 http://www.docgurley.com/?p=204#comment-1044 You are right (as usual) Doc Gurley. Another "coup de grace" study on the subject of whole grain intake and diabetes/cardiovascular protective benefits: American Journal of Clinical Nutrition, Vol. 76, No. 2, 390-398, August. Whole-grain intake is favorably associated with metabolic risk factors for type 2 diabetes and cardiovascular disease in the Framingham Offspring Study1,2,3,4 Nicola , McKeown, James B Meigs, Simin Liu, Peter WF Wilson and Paul F Jacques. You are right (as usual) Doc Gurley. Another “coup de grace” study on the subject of whole grain intake and diabetes/cardiovascular protective benefits:

American Journal of Clinical Nutrition, Vol. 76, No. 2, 390-398, August. Whole-grain intake is favorably associated with metabolic risk factors for type 2 diabetes and cardiovascular disease in the Framingham Offspring Study1,2,3,4 Nicola , McKeown, James B Meigs, Simin Liu, Peter WF Wilson and Paul F Jacques.

]]> By: Helen Howes http://www.docgurley.com/2008/06/14/blind-men-and-the-diabetes-elephant/#comment-1042 Helen Howes Mon, 16 Jun 2008 19:08:24 +0000 http://www.docgurley.com/?p=204#comment-1042 Whole grains are not better for diabetic or pre-diabetic people. There is much evidence that the GI is less helpful than the GL for us too. No grains seems to be nearer the ideal... Exercise and weight loss definitely help, but the biggest risk factor (not addressed) is genetic - there is a strong familial connection, particularly if one's mother, father, or grandparent had the disease... Whole grains are not better for diabetic or pre-diabetic people. There is much evidence that the GI is less helpful than the GL for us too. No grains seems to be nearer the ideal… Exercise and weight loss definitely help, but the biggest risk factor (not addressed) is genetic – there is a strong familial connection, particularly if one’s mother, father, or grandparent had the disease…

]]> By: Doc Gurley http://www.docgurley.com/2008/06/14/blind-men-and-the-diabetes-elephant/#comment-1041 Doc Gurley Mon, 16 Jun 2008 15:33:11 +0000 http://www.docgurley.com/?p=204#comment-1041 I've put the specifics of the Finnish Risk Score (and some more links) into an addendum to the article. Hope that helps you reach the info. I’ve put the specifics of the Finnish Risk Score (and some more links) into an addendum to the article. Hope that helps you reach the info.

]]> By: Ian Furst http://www.docgurley.com/2008/06/14/blind-men-and-the-diabetes-elephant/#comment-1040 Ian Furst Mon, 16 Jun 2008 12:58:33 +0000 http://www.docgurley.com/?p=204#comment-1040 Good post -- I tried to get to the Finnish score but it's password protected. Good post — I tried to get to the Finnish score but it’s password protected.

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