Monday, August 1, 2016

Self-Monitoring of Blood Glucose

Several years ago, some British studies claimed that there was no benefit to self-monitoring of blood glucose (BG) levels (SMBG) in people with type 2 diabetes. I blogged about the studies here, pointing out that of course the testing they studied had no benefit because they didn't also teach the patients what to do with the resulting data.

Some more paranoid patients said the studies were probably funded by the National Health Service so they wouldn't have to pay for glucose testing strips.

One study mentioned in my blogpost did find a small, but statistical, benefit to self-monitoring, and recommended that patients be taught how to use the data they got.

Now, UK researchers have published a study showing that, in fact, self-monitoring improves control when patients are guided in how to respond. The free full text of the study is available here.

The researchers used telemonitoring to guide 160 patients with hemoglobin A1c levels greater than 7.5%. The patients submitted their BG readings to a website where a physician or a nurse analyzed the data and made recommendation on appropriate lifestyle changes. Another 160 were given usual care.

Even though the participants in the treatment arm of the study submitted morning and evening BG levels only twice a week (those on insulin tested more often), their average A1c after 9 months was 7.9% and the patients in the control group had an average A1c of 8.4%. Baseline A1cs were 8.8 and 8.9% in control and treatment groups, respectively. Often just being in a study causes patients to improve their control.

An A1c of 7.9% is still too high, but the difference of 0.51% between groups is approximately the same as the reductions found with drugs like metformin. Interesting that the patients in the control group reduced their A1c by 0.5 from baseline.

Going on a low-carb diet likely would have reduced the A1cs even more, but a little improvement is better than no improvement.

Blood pressure was also lower in the group that received the self-monitoring and advice, but there were no differences in weight between the two groups.

What this study shows is that if you give patients help with interpreting their BG readings, you can improve their A1c levels in a clinically significant way. It also showed that just being in a study makes people more careful about their way of living. If you think someone is watching you,  you're more careful, even if you're not communicating with them every week.

The online method used was certainly less expensive than weekly visits to a health care person, and as we keep saying, strips are cheaper than complications.


  1. I still have to wonder what the advice was that was given and how much advice was actually given.

  2. Bob, I'm sure they didn't give them as low-carby advice as you and I did. The point is that even with what was probably less-than-perfect advice, people were able to reduce A1c better than control, so they can't argue that BG testing is useless in type 2.

    The full text is available and I looked at it but didn't scrutinize every aspect.

  3. What went unnoticed in the infamous Andrew Farmer study was that the patients were told to "maintain adherence to their diet" whether they tested or not. AFAICR the results in both groups were an A1c north of 7.5%. So all that could be concluded was that the diet was crap.

    Many patients have been told NOT to test after eating because "of course your BG will be high, you're diabetic". The nadir was reached by a nurse "If you test your blood you will damage your fingers and then you won't be able to read Braille when you go blind!"

    The main thrust of banning testing I suspect is to save money for the "inevitable" amputations, dialysis, etc. No thought of PREVENTING the decline in health which is seen as inevitable.

  4. I'm not quite as cynical as you are, but I know that cost seems to be a main factor in diabetes care.

    1. No, PRICE is the main factor, not cost!

      What really gets my goat is that Test Test Test aka Jennifer's Advice was first written over 14 years ago, and has been championed by Alan among others on the ADA Forum, leading to people making spectacular improvements in their health for over a decade now - but the ADA don't want to know. To my knowledge many researchers were contacted with a view to making this subject to an RCT, and the few that replied cited inability to get funding. Meter and strip manufacturers and importers in several countries also had no interest.

      Can you think of anyone who may now be interested? Perhaps our Dr David Unwin who reckons to save the NHS over £40 000/year using low carb diets for his diabetics.