I’m a T1 LADA diagnosed about a year ago and have found tremendous BG control using Byetta at Lunch and Dinner (mid 80’s mg/dL), but discontinued using it in March due to a concerning study released by the UCLA Medical School on potential side effects.
Here’s my story and I’d welcome your thoughts, comments and advice in continuing its use, as well as your experience with Byetta if you’ve used it.
I was diagnosed in May 2012 with an A1c of 8.8% and fasting glucose of 236 mg/dL. Tested positive for both GAD and Islet antibodies. C-Peptide at diagnosis was 1.2 and plummeted to 0.2 within about 4 months. For perspective: My A1c was 5.4% at my regular annual physical exam only 6 months before being diagnosed as a diabetic.
I got frustrated with my local endo for reasons not worth elaborating for this discussion, and became a patient of Dr. Bernstein in Sept. By this point I was already following a low carb diet as recommended by Dr. Bernstein (30g/day) and Jenny Ruhl and covering my basal Insulin needs with 18 units of Levemir (9u – morning, 9u – bedtime), breakfast with 1 unit of Humulin R, lunch and dinner with 2 units and 2 units of Novolog, respectively. Fasting and 2hr post meal BG was consistently between 75-95 mg/dL.
One thing I began to struggle with was post lunch and post dinner cravings. This is not uncommon for T1’s, as one of the byproducts of endogenous insulin production is amylin, which creates the sensation of satiety, and I was hardly producing any of my own insulin anymore.
As those of you who have read Dr. Bernstein’s books know, he’s been very successful in helping his T1 patients curb these cravings with “off label” use of Victoza, Byetta and other incretin mimetics. Victoza and Byetta were developed for T2’s and assist in BG control, and were not intended for T1’s at all. However, because these drugs cause delayed stomach emptying, they also create a sensation of post-meal satiety, and hence can be effective in treating cravings in both T1 and T2 patients.
I started with Victoza and found it extremely effective in ending my cravings – almost immediately. However, it also shot up my total cholesterol from 170 to 240 in four weeks, driven entirely by a rise in LDL or “bad” cholesterol. After going through the accompanying documentation I saw that there was a small group of people in the Victoza trials that had experienced the same side effect. I stopped using it and my cholesterol dropped back to 170.
I then switched to Byetta. It too proved extremely effective in eliminating cravings, without impacting my cholesterol at all. The downside to the dosing is that it is not adjustable like Victoza. Byetta comes in two fixed dosage pen types: 5mcg and 10mcg.
I used the 10mcg dose pen along with 2 units of Novolog at lunch and again at dinner for about 3 months. BG control remained good and cravings were gone. Then, at the end of December an interesting and terrifying thing happened soon after dinner: my BG plummeted to 40 mg/dL., and I had made no changes to my insulin or diet regimen.
I then began to wonder if I was beginning to realize some BG control benefit from the Byetta, so I experimented with not injecting any insulin to cover meals and only injecting the Byetta. My post meal numbers were landing in the 80’s. I was amazed. Originally I was only using this to cover cravings, but now it too was providing me with some sort of returning endogenous insulin production. Not only did it give me perfect post-meal numbers, it also seemed to revive my first phase insulin response. My BG stayed flat during and after the whole meal. By this time I was using a continuous glucose monitor to validate this. There is plenty of anecdotal information suggesting these types of drugs can revive beta cells, and it seems this was the case with me.
This was nothing short of a miracle in my opinion and I began to experiment further. I found that it was only good in covering two of my meals a day. I tried injecting it before breakfast, lunch and dinner and found it covered breakfast and lunch, but by dinner the efficacy was gone. Maybe my beta cells were exhausted by this stage? I don’t know. Since my breakfasts were the easiest to cover with insulin, I used the Byetta for lunch and Dinner.
Note that I was still taking my daily Levemir dose, but my needs were starting to rise. In Jan I was up to 20 units/day.
I maintained my low carb diet but couldn’t help experimenting with some “off-plan” foods. For example, I tried a pre-packaged, white bread sandwich offered on a flight that had 70g of carbs listed on the label; zero rise in BG and I remained flat at 85 mg/dL. I had the same result with a cup of vanilla ice cream. Pizza was different: I remained at 80 mg/dL for almost two hours and then shot up to 200 mg/dL, requiring a Novolog correction. Again, these were just experiments and did not become a regular part of my diet.
Then in Feb I started going low after meals with the 10mcg Byetta dose, which suggested to me that my mealtime endogenous insulin production was improving even further. I was then able to cover lunch and dinner with only a 5mcg dose on my low-carb diet. I was now covering breakfast with 2 units of Novolog.
In my consultations with Dr. Bernstein I hypothesized that what was occurring could be the revitalization of my beta cells to the extent that the Byetta was lighting them up just long enough to cover my meals but not so long as to provoke an increased auto-immune response because my C-Peptide numbers held steady at 0.2. He felt that there was merit to this idea, but without any studies supporting this it was difficult to say it was conclusive. All I knew was that this drug worked, and it worked brilliantly. Why? Neither one of us was exactly sure.
By the end of March my Levemir requirements had risen further. I was up to 34 units/day and I was covering my breakfast with 3 units of Novolog. Lunch and dinner were covered with 5mcg of Byetta, respectively. C-Peptide was still holding steady at 0.2.
This was also when Jenny Ruhl posted the alarming results of a just released UCLA study on the side effects of Januvia and Byetta: http://phlauntdiabetesupdates.blogspot.com/2013/03/byetta-victoza-bydureon-appear-to-cause.html
After reading Jenny’s summary I bought and downloaded the actual study and sent it to Dr. Bernstein for his opinion. The study concluded that Januvia and Byetta did indeed spur the growth of beta cells, but they were abnormal. Jenny summarized “The Fatal Flaw with These Drugs: They Cause Abnormal Cell Growth and Pre-cancerous Tumors in the Pancreas.” The study was performed by dissecting the pancreases of participants who had been using Januvia or Byetta for at least a year and had died from non-diabetic related consequences. Bear in mind, the sample size was small: 7 people used Januvia, 1 person used Byetta, 14 non-diabetics were used as a control group. All of the Januvia and Byetta users showed abnormal growth.
I discussed what I should do with Dr. Bernstein. He stressed that while the results are concerning, the sample size was so small it is difficult to argue that this is conclusive. Since there was only one participant who was using Byetta, it is a statistically difficult case to make.
Regardless, I decided to err on the side of caution and discontinue using Byetta regularly. I use it occasionally when I’m at a business dinner in places like Asia where I cannot accurately gauge the protein/carb contents of many of the dishes, and sure enough, it consistently lands me in the mid 80’s. My cravings between lunch and dinner and after dinner have subsequently increased, but nowhere near the levels before I began this journey with Victoza and Byetta. Previously the cravings were all-consuming, now they’re moderately annoying.
I’ve been covering all my meals with Novolog since the beginning of April and some interesting changes have occurred. My 24hr dose of Levemir is still 34 units, but I’ve had to skew the split in favor of my nighttime dose in order to constantly land between the 80’s to 90’s in the morning. Whereas, previously I was splitting my dose exactly in two between my morning and evening injection, I’m now injecting 23 units at bedtime and 11 units in the morning. My mealtime Novolog doses are now 3, 6, and 6 units for breakfast, lunch and dinner, respectively. My diet and exercise has not changed at all over this time. Net: my basal requirements have basically doubled and my mealtime requirements have tripled since September last year. However, my C-Peptide remains at 0.2.
This experience leaves me with some key questions:
- Was my increase in insulin requirements hastened by my Byetta usage? Did I burn my beta cells out or was this just the natural progression of the autoimmune destruction? The consistent C-Peptide value seems to suggest neither, but why do I need more insulin? Remember, diet and exercise have remained consistent over this whole period.
- Did the Byetta foster growth of “abnormal” beta cells as per the UCLA study? Maybe, since I was getting excellent mealtime coverage but my basal needs increased over time. The only way to know for sure is through an autopsy, and I still plan on hanging around for a while. ☺
- Why have I needed to move my basal dosing from a 50:50 night/morning split to a 70:30 split? Dawn phenomenon is the simple answer, but my CGM was showing rises early, middle and the end of my sleep cycle with no clear pattern.
- Do I need to worry about pancreatic cancer? Although difficult to diagnose early, one of the early symptoms is an increase in insulin requirements, which in a non-diabetic would be a red flag, but in a diabetic could be due to any number of reasons.
- Should I continue using Byetta? The benefits have been nothing short of remarkable for me. Will I enjoy these benefits over the long term if I do? The potential risks, however, are troubling but still far from conclusive.
I welcome your thoughts and advice, especially from those of you that have used Byetta. And thank you for taking the time to read through such a long question!
Christopher