HRT after Tymlos

I believe a couple of members here are using HRT after Tymlos, but it might not be one year yet (?) - you'd have to search for their posts. Not sure if you've read my thread "Forteo followed by HRT." It's been 2 years, but I'm not 100% certain if HRT is holding onto the gains - first year DXA results were good but there were confounding factors. My BTMs seem fine and DXA scan for 2nd year on HRT is still pending.

Interesting! Keep us posted . Are you taking any other bone drugs besides the HRT now?

@2024tymloshelp, i sure will. Estrogen (as in HRT) is the only antiresorptive I’ve been on since finishing Forteo.

Thanks - I’m seeing my doctor in a couple weeks to discuss what to do after Tymlos .
My gynecologist thinks I could be a candidate for going back on HRT ( I was on it once before)

@2024tymloshelp , please keep us updated on what you and your doctor decide.

@mayblin, I just got back my bone marker results 9 months after stopping Tymlos. I have been on a .25 mcg estrogen patch for 6 months. As you may recall, I was on .14 mcg of estrogen for 7 months before that along with a half dose of Tymlos. My P1NP is only 17 and CTX is 161. I think the CTX is OK, but I'm wondering if I should be concerned about my P1NP? I have more Tymlos, but am saving it for when I need dental work. I also am considering taking Strontium again, Apparently, all my exercise, good diet and supplements do not build bone. Does anyone know what the ratio of P1NP to CTX should be when trying to hold in gains?

@drsuefowler, i actually think your BTMs look quite reassuring. Your falling P1NP could reflect the anabolic signal from Tymlos wearing off, as well as the expected coupling effect as estrogen suppresses resorption.

By comparison, my CTX were all under 120 and P1Np under 20 during my 2nd year on HRT (i'm using the same E2 dose as you). Most recently, 86 and 15. I take that as suggesting my bone tissue is quite sensitive to estrogen's effect, and that HRT is doing what we would hope during maintenance - quieting down bone turnover. That said, I'll let DXA make the final call.

To my knowledge, there is no scientifically validated target P1NP/CTX ratio for holding onto bone gains. Dr. Eastell and colleagues have published numerous BTM analyses for antiresorptives as well as anabolics, including in the well-known ACTIVE trial of abaloparatide. They had both CTX and P1NP available and, rather than taking the ratio of the two, they developed a more complicated calculation - an "uncoupling index" - using data from ACTIVE trial. That makes me wonder, if a simple ratio were a particularly informative measure, wouldn't that have been an obvious low-hanging fruit analysis to try?

You probably know that SR was never approved in US. In Europe, its use has been restricted because of increased risks of venous thromboembolism and cardiovascular events. SC is an OTC dietary supplement with no efficacy or safety evidence for OP. Would adding SC confound the very monitoring you are relying on - particularly DXA, and possibly BTM? From what i've read, there is no reliable way to correct DXA for SC without knowing bone strontium content. I think this is a good discussion point with your doctor, as it may affect your future therapy decisions.

@mayblin, I don't really want to try Strontium now, since I have been struggling with constipation. I assume that like calcium it would tend toward that. However, I am curious as to what Strontium Citrate would do to the bone markers.

I have one endocrinologist who has prescribed the estrogen to hold in gains. The other endocrinologist doesn't think it will work and wants me to stay on Tymlos. I feel so much better on estrogen without the Tymlos.

Thanks so much for your input, especially your opinion that my bone markers look quite reassuring. Please keep us posted about your ongoing bone markers and your next DEXA results.