Bone turnover markers (CTX and P1NP): do you have a baseline?

I would be interested too Mike. Thanks

I just self-ordered the CTX and the P1NP from Quest, and I am not taking, nor have I ever taken medication. I’ve followed my declining T-scores for 20 years, with the most recent one a -3.7 in the spine and -2 in the femur. I wanted the information, even though my endocrinologist did not feel it was necessary unless I decided to start Evenity, which is what he suggests. Here are my lab results after a 12 hour fast and 8:30am blood draw:
CTX = 480
P1NP = 71
I was very surprised at these numbers. I understand that Dr. McCormick prefers a CTX range between 100-375, but since my blast to cast ratio is about 1:7, isn’t that good? I would appreciate anyone’s insight.

glojo, this isn't insight but I think your ratio indicates that you are slowly losing bone. I find your P1NP impressive. The -3.7 in the lumbar spine strikes me as concerning. I'd rather see you on Forteo, but Evenity may turn out to be a better drug than I think it is. I do think you are wise to have the bone markers. Best wishes with your decision.

Hi @glojo, I agree with @gently’s view. Looking at your results through the lens of premenopausal reference ranges from Quest, your P1NP shows bone formation is quite active, which is great. Bone turnover seems a bit more toward resorption than formation - not extreme, but consistent with what we often see in osteoporosis.

If yiur lumbar spine started normal 20 years ago, your current T-score of –3.7 suggests an average loss of about 2% per year, which is in line with typical postmenopausal bone loss. For context, my spine loss was higher at ~4% per year between age 53 and 59, but I don’t have baseline markers to compare, so it’s just a rough reference. Starting an anabolic treatment could help rebuild bone and improve strength.

Do you have a TBS score? Also, would you share the reason behind choosing Evenity over a PTH analog like Tymlos or Forteo? Thanks!

TBS is 1.141, which is not great. Also had a vertebral fracture assessment which is excellent. The endo, who is unaware of my bone markers, felt that Evenity would result in a faster response, especially in the spine; however, his resident fellow, who visited with me first, insisted on Forteo. Personally, I would be more comfortable with Forteo, if for no other reason than it’s been around longer!
I will also add, for anyone who might be interested, that I have had two REMs a year apart that show -1.8 T score in the spine and -2.3 in the femur, with a fracture risk of 3-5%,.just to add more drama and confusion! I don’t want to stir up a discussion on this thread about REMs, but I do find it all quite fascinating.
Based on my DXA, I was extremely surprised at the bone markers, especially the P1NP, and although high, the CTX was lower than I expected. I am not naive about all of this, but I am somewhat encouraged that my blasts are active at least. Maybe not enough to compensate for the breakdown, but not as dire as I had imagined.

Thanks for sharing glojo. With a lumbar Tscore of −3.7 and TBS of 1.141, guidelines often point toward starting with an anabolic first - it feels like a solid, proactive step at this stage. Evenity usually brings the fastest BMD gains and fracture protection, while Forteo and Tymlos also work very well, just over a longer timeline.

One aspect that doesn’t always get much attention is trabecular microarchitecture. TBS gives an indirect view, but increases can reflect either thicker trabeculae or true reconnection. Evenity mostly thickens what’s already there, while Forteo and Tymlos can do both. It’s hard to say how much that difference matters clinically, but it’s an interesting piece of the puzzle.

Either way, starting with an anabolic sounds like a strong first step. The bigger challenge then becomes how to maintain those gains over the long run, since optimal strategies for cycling anabolics, antiresorptives, and drug holidays are still evolving. On top of that, decisions are shaped by practical factors like insurance, what the current research shows, and the doctor’s guidance.

It’s great to see you taking charge of your bone health. Keep us posted on what you decide.

Tymlos versus Forteo?

Is there data on which of these drugs gets better results ?
My doctor had told me they are very similar and that the benefit to using Tymlos is that it doesn’t have to he refrigerated.
So-
I have done the Tymlos shots for a year now . Only side effect for me has been weight gain inches In my middle section .
With my recent dexa showing no gains I am wondering if I should’ve chosen forteo?
I should add that the dexa showed I did not lose any bone this last year so that’s good . ( if I had been on nothing I read post menopausal women can lose 2% bone a year ? Just wondering if there are studies about which is better forteo vs Tymlos

The ACTIVE trial compared Tymlos (abaloparatide) and Forteo (teriparatide):
https://jamanetwork.com/journals/jama/fullarticle/2544640
Tymlos showed significantly greater gains than Forteo at the total hip and femoral neck. At the spine, both drugs worked well, but the difference between them wasn’t statistically significant. Some have pointed out that this wasn’t a true head-to-head study because it wasn’t fully double-blind for the two drugs.

For fracture outcomes (primary outcome), both reduced risk a lot compared with placebo, and there wasn’t a statistically significant difference between the two drugs.

Since they act in very similar ways, switching from Tymlos to Forteo may not lead to a dramatically different result, imo.

I know it’s discouraging not to see gains so far. Most people do respond in the first year, but there’s a small group (5–15% I’ve read) who don’t show much change. Sometimes it’s just that bone is responding in ways DXA doesn’t fully capture, or it may take longer. It can also help to check vitamin D blood levels, calcium intake, and rule out other possible reasons the medicine might not be working as expected.

2024tymloshelp,
Tymlos is seen to be a stronger medication than Forteo.
The full course of two years is recommended for both because they remodel bone. That process is a longer process than just adding bone to existing structures. The value being that it is more integrated, more resilient bone. The usual advice is that if your bone is weaker in the spine, Forteo is a better bet and for the hip, Tymlos is the best choice.
My first year dexa showed no improvement on Forteo. The second year dexa evidenced the work that the drug has been doing.
The belly fat can be an unfortunate (mean) side effect of pth medications.
This is a retrospective study funded by the manufacturer of Tymlos indicating a reduced fracture risk with Tymlos compared to Forteo.
https://www.sciencedirect.com/science/article/pii/S1530891X24008279

I definitely agree that to start with an anabolic is the best way to go. I had great results from Evenity went from -4.6 to -3.3 in one year this is my t score in my spine.