Sunday, March 14, 2010

SMBG - A Doctor Who Understands


Over time I must admit to developing a certain degree of cynicism about researchers and doctors in the medical research field. I get a little jaded and dispirited about the entrenched attitudes in the fields of diabetes research, especially concerning diet.

Recently, in SMBG Research, Or The Lack Of It, I wrote “There are so many areas of diabetes crying out for research. There are some that have never been studied at all, including those dealing with diet modified by structured testing or similar methods which can lead to minimal medication or insulin needs.”

A friend from the Netherlands has gently chided me by sending me a copy of a paper that shows I may have been a little harsh. Time is the enemy and I only read it in full for the first time today. It's not a research study, more a position or discussion paper, but it is the closest statement from a qualified doctor that I have seen yet to Jennifer's Test, Test, Test advice or my own version of Test, Review, Adjust.

The paper is written by Dr Lois Jovanovic and includes references to other studies in support. Not a lot of other studies, most are small and some are only obliquely relevant, but at least there is some research happening in the field. It is so pleasant, after years of reading so many doctors ignoring so many patients on this subject, to finally read a paper like this one. They can ignore diabetics like me and dismiss us as unqualified; but Lois Jovanovic is someone who may be harder to ignore.

I think two unique factors make this particular doctor more aware of the close relationship between carbohydrate input and post-prandial hyperglycemia than most doctors. First, she has a depth of experience especially in gestational diabetes and pregnancies in patients already diagnosed as type 2. That has led to experience in trying to attain and manage normoglycemia much tighter than the levels usually expected for most type 2s. Her bio, in part reads:

Dr. Jovanovic has authored over 240 articles, including 135 for refereed journals, and 25 books on the topic of diabetes and pregnancy and islet cell transplantation. She serves as an Associated Editor of Diabetes Care and is on the editorial boards of Clinical Pharmacology and Therapeutics and the American Journal of Perinatology and is a contributing editor for the Journal of the American College of Nutrition and special editor for Endocrine Practice, the official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists. In addition, Dr. Jovanovic serves on the national board of directors of the Society for Experimental Biology and Medicine.

Not someone whose opinions on diabetes can be lightly dismissed.

Second, Lois Jovanovic is a type 1 diabetic. Uniquely, she is the grand-daughter of an 8-year-old type 1 girl in the original group treated by Banting when insulin was discovered. I found this fascinating article on her story here: Dr. Lois Jovanovic's Story. The discovery of insulin did not just save her life as a Type 1; she would never have existed at all without it.
The abstract of the paper can be found here: Using Meal-Based Self-Monitoring Blood Glucose (SMBG) Data to Guide Dietary Recommendations in Patients With DiabetesLois Jovanovic, MD, MACE
The Diabetes Educator, Vol. 35, No. 6, 1023-1030 (2009)DOI: 10.1177/0145721709349587

The purpose of this article is to describe how self-monitoring of blood glucose (SMBG) data is a useful tool for identifying and managing postprandial hyperglycemia (PPHG).

PPHG and postprandial glucose excursions occur frequently in patients with diabetes even when hemoglobin A1C is controlled below 7.0%, and convey increased risk of cardiovascular morbidity and mortality. Consequently, effective management of diabetes must include control of postprandial glucose levels. Postprandial plasma glucose (PPG) depends on the composition of meals, specifically the amount of carbohydrates.

Reduced-carbohydrate diets offer short-term improvements in glycemic control and other metabolic parameters, but await the support of long-term efficacy and safety studies. Glucose profiling and paired-meal SMBG are useful tools for detecting PPHG and glucose excursions. They provide immediate feedback to patients on the effect of foods and meals, thereby allowing appropriate food and medication adjustments to improve postprandial glycemic control.

But that abstract does not give an inkling of the specific recommendations in the full text or the pleasant shock I received when I read this marvellous “To Do” list for guiding dietary recommendations that is included as Table 1:

Educate your patients on the risks associated with high peak-postprandial glucose concentrations (≥150 mg/dL)

Ensure patients understand that postprandial glucose concentrations are determined by the total amount of carbohydrates consumed

•• Encourage patients to measure their carbohydrate consumption

•• Recommend that patients keep a food diary

Remind patients of the benefits of monitoring their blood glucose levels with SMBG and construct a testing plan that optimizes these benefits

•• Have patients determine the best time for postprandial SMBG by testing 45, 60, 75, 90, 105, and 120 minutes after a meal to detect their peak postprandial glucose concentration

•• Using preprandial and postprandial SMBG, together with a food diary, patients can understand how certain foods influence their glucose concentrations

•• If preprandial glucose concentrations are already high, there is no room for carbohydrates in the upcoming meal

Review recent SMBG and food diary data with your patients to help them recognize trends in out-of-target readings

•• Use this information to recommend a specific SMBG testing schedule including number of tests per day and appropriate testing times

•• Have patients meet with a nutrition specialist if they are having trouble identifying or controlling their carbohydrate consumption

Personally, I was particularly pleased to read the recommendation to find the post-prandial peak and use that as the best time.

I could hardly have asked for a better list of advisory guidelines from a doctor. I hope her paper is widely distributed among her peers. It should be required reading on the boards of organisations such as the ADA, NHS, CDA and Diabetes Australia.

Cheers, Alan, T2, Australia.
Everything in Moderation - Except Laughter

5 comments:

eclectic.hermit said...

I have been a type two diabetic for two years. When first diagnosed my doctor gave me a prescription for a glucose monitor and metformin. I met with a nutritionist and set my carb limits on a daly basis. I next got me a carb counter and meal planner. It is common sense to me to set up what happens to your glucose levels after a meal. Take readings before and after the meal to see how that meals food combinations affected your levels. Next time choose different foods. Take charge. Of course remember that after a while, several years even the best of diets won't help much and neither will exercise or meds (unless a new med comes along). Good luck.

trinkwasser said...

Couldn't agree more. Many "studies" of SMBG call four times a week "intensive" or insist only on fasting or preprandial testing which completely misses the point and ensures it has no effect. Here's another doctor, this one not diabetic but with a Type 1 son

http://www.dsolve.com/how-to-course-othermenu-59

Here's a more positive look at testing (if Kaiser think it's cost-effective then it must be)

http://care.diabetesjournals.org/cgi/content/full/29/8/1757

There are a few such papers around, but none this comprehensive

diabetic neuropathy said...

I have been diagnosed with type 1 diabetes 4 years ago and to be honest I have had hits and misses when it comes to diet and nutrition. These to-dos are what my doctors have done for me over the years, and I think that these are best practices. It's amazing how Jovanovic was able to put it all together. Do you have the full text with you?

Worried! said...

This is making me worried about my horrific postprandial spikes now. My overall control is ok (5.9 - which I would like to improve on but which my diabetes team thinks might be too tight control, but they don't have to live with it do they?). Having only been recently diagnosed, I was told by the nurses not to test post-meal 'as the numbers would naturally be high' but to only test before the next meal.

I recently attended a DAFNE training course on matching insulin to food. Under this regimen, you test (and make any necessary adjustments) at the next meal. I found that when I counted my carbs right, my boluses were usually spot-on and my BG was back in normal range by the start of the next meal.

Now though in doing postprandial checks as well, I found horrific spikes. Routinely in double digits mmol. Plus I have another problem (on top of all the other known ones!) - my rapid-acting insulin takes a very long time to work. It does absolutely nothing for the first two hours, starts kicking in around 3 hours and peak action is in around 3.5-4 hours. Usually finishes action by 5 hour mark.

So what this means is that for those 3 hours when the insulin's just chilling out, my BG is in the stratosphere, but when it eventually works, it works *mostly* exactly as it's supposed to.

How worried should I be about these numbers? I have tried injecting earlier but worry about going hypo (on the off chance that sometimes the insulin would actually work as rapidly as it is supposed to).

I can even get spikes on zero-carb small meals. 90mins postprandial on a small omelette last week was 11.5 when fasting BG before that meal had been in normal range!!!

Anonymous said...

Thanks for posting this article. Her point: "If preprandial glucose concentrations are already high, there is no room for carbohydrates in the upcoming meal" has really resolved a lot of issues for me. I had a real "lightbulb" moment when I read it (and yes, I admit to being slow on the uptake sometimes)...

Prior to that I was struggling with Jennifer's 'test, test, test' method after a couple of weeks of cutting down carbs, etc. If anything, my morning Fasting Blood Sugar was higher than it had been when I wasn't cutting carbs and blissfully thinking my BSL was great because I was only measuring at 2 hours. Once I started testing, I couldn't understand why I could eat the same breakfast from one day to the next and have perfect control some days and be spiking over 10 mmol/L at 1 hour on others. This advice taught me to only eat carbs with breakfast if my fasting BSL was under 6.0. I'm also finding a bedtime snack of higher carbs makes my fasting BSL better the next morning. It's all so amazingly individual that I now can't imagine anyone being able to control the BSL any other way than Jennifer's method. Rather like a high school experiment that I have very distant memories of.

Thank you so much for your blog - I'm finding a wealth of information here and at Blood Sugar 101.

Jill, Perth, WA
Recently diagnosed T2 @ 60yo