Value of bone turnover markers
I had thought it would be useful to get reads on my baseline P1NP/CTX as I am finishing Tymlos and just starting a bisphosphonate. But neither of my doctors (a rheumatologist and an endocrinologist) wanted to order these tests -- both said they get them (or maybe just the CTX) after one year on the bisphosphonate. I found that weird since the rheumatologist ordered the measure of these bone turnover markers both when I first saw her and when I was on Tymlos for four months. Have you gotten different recommendations from your doctors??
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It sounds as though they don’t think it would be beneficial at this juncture. They are routinely ordered before starting treatment so that a baseline can be established. They are also many time ordered to see if a med is working to help decide if a med should be continued.
You don’t fit into either of these categories. Perhaps that is why they don’t think they would be beneficial
It is a little weird as you are starting a new drug so in theory a new baseline might be warranted.
You might ask if they could be ordered for your peace of mind. That way, you are not directly challenging their medical judgement. Just an idea
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4 ReactionsI 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.
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1 Reactionsebutler, 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
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3 Reactions@gently I’m surprised how reasonable the pricing is. That’s great
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2 ReactionsReasonable pricing? Except in comparison to my insurance which pays 100% when ordered by a doctor. My PCP was reluctant to order biomarkers and then said he would be surprised if insurance approved but then there was no problem.
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1 ReactionInsurance 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.
@laura1970 Thank you for this suggestion. I discovered when I got recent bloodwork done that in fact my endocrinologist, unbeknownst to me, did order the CTX -- tho for whatever reason not the P1NP!
@prarysky Wow--what. you went through to get bone turnover markers tested!
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2 Reactions@gently Thank you once again for sharing all this information.
As I mentioned in my reply to @laura1970, it turns out my endocrinologist did order a CTX, unbeknownst to me, tho not the P1NP test. I just got the results of bloodwork.
The kicker is that my CTX already dropped -- Before I started Tymlos or any other drug, my CTX was 250 (tho it was measured around noon on the day I first saw my rheumatologist). About a year later, after being on Tymlos, it jumped to 1,000 -- all to be expected, my rheumatologist
said, since Tymlos raises both CTX and P1NP. Now, it has dropped to 308, almost back to where it started. I am thinking that this means the Tymlos is no longer working. According to the research that the pharmaceutical company does, CTX drops to baseline 1.5 years after beginning Tymlos, but P1NP stays elevated about 45 percent above baseline. Hope that is true, but would certainly love to see my current P1NP to test that assumption. As suggested by laura1970 and prarysky, I just sent a msg to my endocrinologist asking for a P1NP.
You are so right: Our doctors expect that the medications they prescribe are going to work, so don't bother with the bone turnover markers. I would have expected that my rheumatologist, who is at Cleveland Clinic and specializes in bone diseases (osteoporosis, Paget's disease, etc.), would have ordered the P1NP and CTX as I switch to a bisphosphonate, but no. My rheumatologist also discounted the research someone on Mayo Connect referenced, showing that the incidence of ONJ is .7 percent for those on bisphosphonates for osteoporosis who have had a tooth extraction (not the .06 percent she had cited, which I had thought misleading because it took a broader sample of patients, that is, all patients taking the drug, not just those who had invasive dental work).
You have a wonderful doctor -- wish I could adopt him!! So your Forteo is still working. That is great. Have your bone turnover markers changed over time?
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3 ReactionsDid your rheumatologist offer any reasoning for discounting the ONJ research? It would be so helpful to know how some of these medical practitioners think.