Dapagliflozin, Type 1 diabetes, heart failure and ketoacidosis...anyone with experience of this combo?

[Poppeye]

My wife was recently diagnosed with severe heart failure and an LVrEF of 30-35%. She has had permanent atrial fibrillation for the last 14 years and has had type 1 diabetes for over 40 years.

When she was discharged from hospital she was given a variety of medications which the dispensing nurse went through and explained one by one. When it came to the Dapagliflozin, however, she was puzzled as to why it had been prescribed as she thought that it was not suitable for a type 1 diabetic. She withheld it and crossed it off the list.

The hospital cardiologists had been confused about her diabetes and didn't want to accept that she was type 1, despite it being clearly stated on her notes and her having been type 1 and using insulin at least 4 times daily for over 40 years. It was an odd situation.

I had expected her to be told about the blood sugar lowering effect of Dapagliflozin and advised that she might need to adjust her insulin dose accordingly. Dapagliflozin is supposed to have some clear benefits for heart failure, my wife has very good blood sugar control and would never run the risk of ketoacidosis (a known side-effect of Dapagliflozin) by allowing her blood sugar to rise to dangerous levels.

When my wife saw the heart failure nurse a few weeks later, she brought this up. The nurse thought it was a good point and said that she would bring it up with the cardiologist as it seemed unhelpful to deny her a drug with a clear benefit because of a practically non-existent risk.

She hasn't had a reply to that query, she will see the heart failure nurse again next week and will bring up the subject again. I am not sure, given the cardiologist's previous confusion about her diabetes, that he has a good grasp of diabetes management. Meanwhile, her GP has said that she doesn't think that Dapagliflozin is a good idea. Perhaps she doesn't know how well controlled my wife's diabetes is, or perhaps there is some other circumstance, not connected to high blood sugar, that might trigger ketoacidosis in her case?

Sorry to be so long-winded, it is complicated. Neither the cardiologist, the heart failure nurse nor the GP seem to have a clear answer as to whether Dapagliflozin is a good idea or not in her case...I wonder if anyone has any "real world" experience of this...?

[Happyrosie]

I expect you are already familiar with it, but the website of Diabetes UK might help?

[Goldenre in reply to Happyrosie]

Should be looked into by not only a cardiologist but also an endocrinologist. Found this on Drugs.com. "Dapagliflozin is not for people with type 1 diabetes. Dapagliflozin may increase the risk of diabetic ketoacidosis (increased ketones in your blood or urine) in people with type 1 diabetes."

[Poppeye in reply to Goldenre]

Yes...that's right. Under normal circumstances it shouldn't be given to people with type 1 diabetes as they are already taking insulin to control their blood sugar and the dapagliflozin will double up on the insulin and interfere with their control. But an experienced diabetic will be able to take this into account and adjust their carb/insulin to account for it.

What I really don't understand (and I suspect that neither the cardiologist, the heart nurse nor the GP do either) is that the effect of dapagliflozin is to lower blood sugar levels, but ketoacidosis, the known and dangerous, side-effect of dapagliflozin, is associated with high blood sugar levels, not low levels.

I feel that, if my wife could be trusted to manage her diabetes properly (which she can) then she would be able to benefit from this drug's effect on her heart failure.

[Poppeye in reply to Goldenre]

By "endocrinologist" do you mean her diabetic management team? I have a feeling that they would repeat the advice that it shouldn't be used on type 1 diabetics. They would not take into account the drug's beneficial effect on heart failure as it is not their area of expertise.

And we have already had the muddled opinion of the cardiologist who doesn't seem to understand that the day-to-day management of insulin-dependent diabetics is in the hands of the patients themselves who are used to fine-tuning their blood sugars without the need for "expert" medical advice

[Goldenre]

As an RN, retired, who previously worked in a diabetic unit, I applaud your wife for the excellent management of her T1D. It just seems to me the experts should be addressing the drug issue more seriously with the ongoing HF.

[Poppeye]

I have finally understood the problem with dapagliflozin and type 1 diabetes.

Insulin reduces blood sugar by making it available to muscles, the brain and storage in liver tissue. Dapagliflozin reduces blood sugar by dumping sugar into urine via the kidneys. The blood sugar is reduced, but the muscles, brain and liver receive none of it.

If you are insulin dependent then dapagliflozin will reduce your need for insulin. But this means that you will not be "feeding" your body and it will respond by trying to make more sugar from storage, initially from the liver but then by breaking down muscle tissue. The by-product of this process is ketones.

Ketoacidosis is caused by the lack of insulin, not by elevated blood sugar levels, although in type 1 diabetics, high blood sugar will be present when insulin levels are low.

The same will not be true in a type 1 diabetic on dapagliflozin. They may have normal blood sugar because the excess sugar has been dumped, but they may also have low insulin levels because they did not need to take any insulin because their blood sugar was normal.

I can now see why it isn't a good thing for type 1 diabetics even though it has clear benefit for heart failure. It could work but only if ketones could be monitored carefully...

[ScotchLad]

Hi

Iam type 2 diabetic on metformin. I was also prescribed Dapagliflozin for heart failure and so far no issues.