Value of bone turnover markers

Insurance usually pays. if your doctor cooperates with the requisition. In defense of our doctors, the bone marker were less reliable in the past (when these doctors were in school). Research has now established the best reagents and the process has been standardized. Still, it is easy to compromise CTX results with use of biotin, lack of sleep, prior exercise and a late in the day draw.
Often the requisition requires a Statement of Necessity, hard to sign if you don't think the test necessary. But also, extra work struggling for approval.
More than anything though osteoporosis isn't center stage. Most doctors have more patients with diabetes and are much more focused on that and other diseases in their practices. An estimated that 80% of women in the US with low bone mass remain diagnosed. It is difficult to keep abreast of the research involving even one diagnosis.
The use of bone markers is not standard care. If we keep asking for those bone markers, maybe standard practice will change.

I agree with your instinct to want those bone turnover markers as a baseline before starting a new drug. It's odd that your rheumatologist is reluctant to order the tests now when she'd done so before. You might ask her for her reasoning about that. One hopes that doctors can hear a question and not get too defensive about it.

Prior to starting Zometa, which is similar to Reclast, I requested a baseline as well. The Zometa was recommended by my oncologist because of being on an aromatase inhibitor which is linked to serious bone loss. Although my recent Dexa scan indicated osteopenia, my FRAX score was considered high. I did not want to fracture so accepted my oncologist's advice. The breast cancer diagnosis ruled out anabolic osteoporosis drugs which would have been my first choice. They weren't even suggested by any of my doctors (oncologist, endocrinologists)

My oncologist would not order those bone markers, however, saying she didn't know enough about them. She referred me to my primary care doctor who also would not write an order saying she, too, didn't know enough about them. I searched around and found an endocrinologist whom I could see without waiting 6 months. I told her my interest in having the bone turnover markers tested. She said this is usually done after a drug has been used to see if it is working. I asked didn't it make sense to have a baseline PRIOR to starting to be sure the drug was working.

She somewhat reluctantly agreed and wrote an order but she also made it clear that she would not really work with me to interpret the test results. Odd but whatever. At least I had my baseline results. She ultimately did send me a note saying my bone turnover was high so the Zometa/Reclast infusion made sense.

Meanwhile, I finally got an appointment with a different endocrinologist who works in the same health system as my oncologist. She is relatively young and I'm glad I found her. She seemed more open in her discussion with me. She agreed to test me again 6 months after my Zometa infusion. I've seen some people checking results more frequently than that, but with an infusion, I don't see the need to do that.

I like Laura1970's suggestion. If they are non-responsive, you might seek out another opinion from a different endocrinologist if that's an option for you.

@gently
I am aware of the history of these biomarkers and of course, the protocol before blood draw for a CTX test. But seems to me that a medical practitioner who is comfortable prescribing osteo treatment ought to stay abreast of acceptable monitoring procedures, given the side effects of any of these drugs and their cost.

Could not agree more about the diabetes epidemic's role in affecting the health care of the rest of us.....it is my experience about the difficulty of even getting an appointment with an endo.

If I was to try to convince a PCP to order biomarker tests, is there research and/or literature that could be the most persuasive? And who issues the 'standard care' about the use of bone markers?

@prarysky Wow--what. you went through to get bone turnover markers tested!

@gently I’m surprised how reasonable the pricing is. That’s great

sebutler, yes. To measure the effectiveness of Reclast you would want the post Tymlos CTX and a CTX 3 to six months in. A 20% drop in baseline would be considered successful treatment It is quite useful after the first year of Reclast to have another CTX before deciding to take a second injection or to wait. Resting that decision until 6 and 12 month CTX serum draws indicate need.
If you are beginning an oral bisphosphonate, you might want the same level of testing, but with the orals you could alter dosages for best outcome.
The endocrinologist I see orders CTX and P1NP every six months. I want both because essentially we are wanting to balance CTX with P1NP. The best balance is not known, but speculated to be 3 -5 CTX to PNP.
My endocrinologist doesn't use the two markers in relation to each other. I'm on the third year of Forteo, and he feels like he knows Forteo is effective and that we no longer need the bone markers, but he already promised me that he would order them in this way.
The use of bone markers isn't widespread. Doctors are more likely to order them if they are in an osteoporosis -only practice, or if they are involved with research on osteoporosis.
Our doctors expect the medications to work for us, and they are usually right. But there are patients for whom the medications aren't effective and after year or two of tolerating side they sometimes realize that their osteoporosis has only progressed.
You can order your own CTX in some states the best price I've seen is with Jason Health.
Collagen Type I C-Telopeptide (CTx) $50.00
Lab Collection Fee $18.00

kshea2, hi.
These are my thoughts regarding bone markers, but I'm not a medical person or statistician. And my doctor says that you can't use bone markers in relationship to each other.
We want our bones to break down but want a commensurate building up, CTX and P1NP are measured products of bone destruction and construction. Your 370÷82 = a ratio or 4.5, withing the range I consider preferable. At a ratio of 5 to 1, I think there is a balance where you are not building new bone, nor losing more bone than you are replacing. At 6 CTX to 1 P1NP it looks from a careful study of various clinical trials.
As brilliant as he is, the endocrinologist I see only looks at my P1NP. Since it is now double my base line, and I'm on an anabolic, he is content that the medication is still working. If I were on an antiresorptive, he would only look at the CTX for reassurance wanting it to be at least 20% lower than baseline.
He wouldn't consider your numbers to yield information without baseline.
I also consider that I need higher numbers than a younger person, because my older bones need more repair. A person with a fracture would also need higher CTX initially and higher P1NP at some point in the process

( as an unnecessary aside McCormick and Lucas both convert pg/mL to ug.L (or ng/mL before finding the ratio. Lucas remains uncertain of best ratio though he is certain that there is one.)
All of this is unnecessary to explain that to get the ratio divide the CTX by P1NP. My last bone markers were CTX334/P1NP 117 which puts me at a nice 2.8, though I'd like both numbers to be higher. My endocrinologist looked at the P1NP which is about double baseline and was happy no matter the CTX.