Insulin alone or with metformin?

[cbrsmurf]

So the American Diabetes Assoc. recommends insulin-dependent patients be on metformin, but I get a lot of new patients who are just on insulin. I know the ADA guidelines can take a while to change. Are there any good trials regarding insulin-alone vs insulin + metformin?

 

thoughts?

[Acebecker]

I'm not familiar with any studies, but in practice if they're well managed on insulin and the A1C is good, then no need to mess with it. Just use insulin to keep control. Metformin bears with it the risks of GI upset, lactic acidosis, blah blah blah.... Insulin bears with it the risks of hypoglycemia. In general, a well educated and compliant patient will not have trouble with hypoglycemia, but it's hard to attenuate the risks of metformin (however rare they may be). So if there's control with insulin, no need to be on metformin. And I've had good luck with this approach. However, if someone is on metformin and I add insulin I don't usually take them off metformin because the transition can be quite rocky. You'll have a lot of trouble predicting baseline insulin requirements as they change rapidly as you change the metformin dosing.

 

Again - this is my logic driven approach and is not gleaned from review of research. So, take it with a grain of salt if you find resources that tell you otherwise. I've had no problems with practicing this way and get good results.

 

Andrew

[ventana]

I usually try to keep people on both, lower insulin resistance and provide insulin

 

but gotta have good renal function, and I tend to hold off the metformin if also on lasix and NSAID as the risk to kidney to great, but if just on insulin, ace, statin, ASA and Metformin........

[sbellin]

I assume when you say “insulin dependent” you are actually talking about a Type 2 diabetic requiring insulin.

In my practice there is no hard and fast rule that if you get started on insulin that the metformin goes away. As a general rule the metformin stays unless there is intolerance or renal disease. Adjunctive insulin use has a potential physiologic down side with side effects such as weight gain and the increased sodium retention. The literature lately seems to be downplaying the risk of lactic acidosis though it can’t be discounted. There is also a financial impact as well; metformin is cheap and insulin is not. If you can keep their expensive insulin use to a minimum by keeping the cheap metformin on board there is a greater chance in adhering to the prescribed regimen.

[rcdavis]

I assume when you say “insulin dependent” you are actually talking about a Type 2 diabetic requiring insulin.

didn't know that.

 

For decades Eli Lilly company would make insulin available to T1DMs for free if needed. I have not used nor tried this service in years, but I suspect it is still true... Have you tried contacting them to see if they would help with your less well off, non-insured patients?

[cbrsmurf]

Thanks for the responses.

Yes, I meant type 2 diabetics.

So the way I am thinking: in T2DM, metformin has the strongest evidence and best patient outcomes with the added benefit of weight loss. That is why it is first-line. Insulin, which is often necessary to control symptomatic and/or very high glucose levels, has poorer outcomes. Obviously, most patients on insulin typically tend to be in poorer health. So what runs in my head: why would you not give a patient the best medication (metformin)? Is there a significant risk of hypoglycemia? Does metformin cause increased fluctuation in daily glucose levels?

[MedicinePower]

http://www.medscape.com/viewarticle/804698?src=wnl_edit_newsal&uac=118841CY

 

[h=1]"FDA Approves AIC Test to Diagnose Diabetes"[/h]

[cbrsmurf]

i can't access the article, but what does it have to do with the topic

 

i believe the ADA had already approved A1c for DM diagnosis for at least a year now...

i've been practicing for a little less than a year and i have ordered an ogtt only a handful of times (hemoglobinopathies).

[MedicinePower]

i can't access the article, but what does it have to do with the topic

 

Medscape is free and an excellent resource. The FDA just approved the test today so I thought it might be interested in a discussion about DM.

[KMD16]

i can't access the article, but what does it have to do with the topic

 

i believe the ADA had already approved A1c for DM diagnosis for at least a year now...

i've been practicing for a little less than a year and i have ordered an ogtt only a handful of times (hemoglobinopathies).

 

Kinda. However, in addition to a fasting glucose. Last I checked, the endocrinologist society opposes A1C as a single diagnostic marker for DM.

[cbrsmurf]

Kinda. However, in addition to a fasting glucose. Last I checked, the endocrinologist society opposes A1C as a single diagnostic marker for DM.

 

Interesting, you are right. Their position statement claims that as many as 20% fewer diagnosis could be missed, although they do not provide a reference/study.

[d2305]

I have had good results with GLP1s, but they are expensive.