@rjd If you do a search on: mayoclinic ctx p1np
you will find several discussions of BTM Bone Turnover Markers.

Here is an example thread with posts from this year, but there are several others, including ones posted by me:
https://connect.mayoclinic.org/discussion/bone-marker-tests-ctx-and-p1np/

@rjd Hi there, yes, I am doing my own tracking of blood markers. After successfully taking Evenity for a year I switched to monthly Risedronate. In order to know if Risedronate was holding my Evenity gains I did a number of CTX and a couple of P1NPs to see what was happening with my bone resorption primarily. I did monthly CTX tests for 3-4 months , 1 before and several after starting the Risedronate. In my case I saw that the CTX stayed down below 300 for about two weeks but by 4 weeks it was climbing to 350-400. I considered that to be too high a CTX reading for keeping my bones. I started taking the monthly Risedronate every two to three weeks after seeing that pattern.
Unfortunately I did not maintain that level of thoroughness due to various life events. Though I did continue to do the CTX tests it became less consistent. But also logical that after I saw the pattern I did not need to test as often. 15 months later at my next DXA and TBS my readings had improved. Unfortunately one of the life events included me moving across country from the DXA machine I had been tested on for years. So the next (recent scan) was a different machine, different maker, different technician. So can't compare before and after the Risedronate as well as I would like. But the numbers being better makes it unlikely that they would be worse if I had measured on the same machine again. I conclude I either gained more on Risedronate or at worst lost only a little.

Now I've stopped Risedronate due to needing dental implants. I will resume tracking CTX and P1NP to help gauge whether I'm in the right condition for implants. And that I'm not losing rapidly after stopping the Risedronate. Not claiming any of this is exact and certain but it's one of the only ways I know of to help make best guesses.
For instance if my CTX had gone up and stayed up despite the Risedronate i would have talked to my doctor about changing meds. As it was I knew pretty well that the Risedronate was working though not perfectly. I could relax knowing I wasn't losing my Evenity gains.

The total cost for each CTX test was $68 via Jason Health with the blood draw done at Quest. Jason Health was very easy to work with.
Good luck with your efforts!

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