Dexa “T” scores and “Z” scores—- need advice

[Pamk1949]

I have GCA/PMR (temporal biopsy negative) and previously posted that my “new” (we moved) rheumatologist and eye doctor doubt that I ever really had GCA. At that time, I was put on high prednisone 100 mg, because of several Amaurosis Fugax attacks, as well as all the other symptoms. It’s been a year now, and I tapered down to 12 mg without any events.

I finally went for another opinion, this rheumatologist did several tests (for other auto immune s—results not back yet) and suggested that I probably did have GCA. At that meeting she suggested taking Fosamax or similar since I was on high doses of Pred.

Right before the first diagnosis, my T score of left hip was -2.4, and the Z score was .7

I know that I’m close to osteo with my T score, but doesn’t my Z score of .7 mean I am normal for my age of 68? What are your experiences, opinions and advice? I’m really afraid of the bone medication, yet also afraid of losing my bones! I have followed Heron’s advice on K2, calcium, diet, walking and weight bearing exercises. I really respect and appreciate suggestions from this site. There is a prescription waiting for me at the pharmacy. Should I take it?

[HeronNS]

As it's been a year and you are in a new community is it possible for you to have a follow up DXA scan before you start the medication? Ideally, of course, it should be on the same machine to get an accurate comparison but what you really need to know is what your reading is now.

If you do decide that medication is the best option for you, you are probably aware that the best results occur within the first two or at most three years and after that the likelihood of side effects increases.

Good luck.

[SnazzyD in reply to HeronNS]

Is there much variation between machines then?

[PMRpro Ambassador in reply to SnazzyD]

There can be. I can only find the bald statement on tinterwebs - no reasoning behind it. I just know that is what they have said all along!

Even your height and build influences it - they will underestimate bone density in short people and overestimate in tall ones.

[SnazzyD in reply to PMRpro]

Any idea what sort of error?

[PMRpro Ambassador in reply to SnazzyD]

I don't know offhand - but it is a more comparitive measurement than absolute and the angles the x-rays strike makes a difference I think. You can also measure body fat with dexa so that probably is involved.

Does this help?

scienceforsport.com/dexa-sc...

"The differences in the reported validity of DEXA scans for body composition may partly be due to differences in software, manufacturer, and the wide range of body composition values across various cohorts. It is worth noting that although current research is conflicting, it is commonly assumed that DEXA is a valid technique for the assessment of body composition."

[HeronNS in reply to SnazzyD]

I've read that even the technician should be the same! It does make one wonder just how wonderful these machines are doesn't it? it's something to do with the calibration, although I imagine as time has gone by this situation has improved and all modern, regularly maintained machines should be more identically calibrated. But I'm just guessing, really. There is always a small allowance for error. When a marked difference is noted between consecutive scans the first question should always be whether the same machine was used. It's also imperative that you be positioned in as close to the original way as before. My second scan was painful because I'd been having physiotherapy in the intervening year and my back was straighter. I had to be twisted into an uncomfortable position, and hold it of course, in order to get an accurate image. The result was severe back pain which required further physiotherapy and a new set of exercises!

[Pamk1949 in reply to HeronNS]

So I can take this short term then 1-2 years? Yes, another Dexa is ordered, but not until January. I’m going to ask for a dexa next week. Thanks Heron! By the way do you happen to know which medication is the best? Or is it more complicated than that.

[HeronNS in reply to Pamk1949]

if you take the meds at all the less you need the better as far as I'm concerned, but I have my own, probably better not expressed, opinion of these meds. I have no medical training but from reading I'd suggest you avoid Prolia (denosumab) like the plague because although it gives good results when started, it's very difficult to come off safely as it's now been shown that the risk of rebound osteoporosis (and fractures) seems quite significant when Prolia is discontinued, so one has to take another medication anyway until those after effects have worn off.

If you go over to the Bone Health forum you'll see a number of discussions started by people wondering if there will be class action suits against Prolia and describing their own, often horrendous, experiences. That forum has people contributing who can probably answer your questions about the different medications.

[Pamk1949 in reply to HeronNS]

Wow thanks for that info. What do you think about the once a month medication, or maybe the weekly Fosamax?

[HeronNS in reply to Pamk1949]

Pam, I really don't know. I only know what I will do for myself and it doesn't include osteoporosis drugs! but I wish you wll whatever your choice!

[Pamk1949 in reply to HeronNS]

Thanks for your help. I’ll investigate the bone forum too! And will keep you advised as to my big decision.

[HeronNS in reply to Pamk1949]

This is a particularly interesting and helpful site:

betterbones.com/

[HeronNS in reply to HeronNS]

And this one: saveourbones.com/

You don't have to buy anything from either of these sites, there's a lot of information in the articles they've published.

[PMRpro Ambassador]

The Z-score is fairly meaningless - it just compares us with all the other crumblies! Not that any of the figures are that certain as they just chose a number to be the borderline without any real evidence. Many people with low bone density don't have fractures, most fractures occur in people with "normal" bone density. But...

Your t-score is very borderline but it is your decision - I think even I would consider trying it, especially if you can get another dexascan. You can't compare it directly with the previous one but it should show whether you are that close to osteoporosis or not.

[Pamk1949 in reply to PMRpro]

Yes I’m afraid I might have to take this. My mom had very bad osteoporosis and had a really hard time with the medication. I was hoping since my Z score correlates to my age peers, that I would be considered “normal”. I guess there’s more to it.

[HeronNS in reply to Pamk1949]

But you are not your mother and your nutrition and exercise history will be different. Genes are, I think, only a small part of the bone thinning picture.

[PMRpro Ambassador in reply to Pamk1949]

Being "in normal range" doesn't make something healthy. Low vit D was ignored for a long time as almost everyone had similar levels - but they aren't the sort of levels that contribute to optimum functioning.

[Constance13]

I have been taking bone medication for 2 1/2 years now and have had no problems. At the start my t-score was -3.4, now it’s -2.2 so I don’t have OP any more. I’ll still keep taking it until it’s down just a tad more, then we’ll see.

[Pamk1949 in reply to Constance13]

Thanks that’s good to know, and wow you have made improvement! What medication are you taking, if I can ask?

[Constance13]

It’s an injection every three months (Bonviva) it’s an Ibandronic acid. I live in Germany so don’t know brand names in different countries.

[PMRpro Ambassador in reply to Constance13]

The substance name is always the same - ibandronic acid.

[Pamk1949 in reply to PMRpro]

Thanks!

[Pamk1949 in reply to Constance13]

Thank you !

[Jamie345]

I had a fusion of andronic in the hospital I was told that I could have side effects like a dose of flu that night I went really ill high temperature the lot, but at 3.am it suddenly all started to ebb I was fine by morning! I had to have it this way as I cannot take it orally. It's a once a year thing thank goodness I have multiple fractures and osteporisis I've lost height as well, anyway just thought I'd inform this way of taking andronic to strengthen bones? O

[Pamk1949 in reply to Jamie345]

That’s interesting...once a year. Is your osteoporosis from prednisone? I’m sorry to hear that you have had all those fractures. Hope you are doing better now...thank you I’ll research that andronic!

[PMRpro Ambassador in reply to Pamk1949]

It isn't andronic - sounds like an alien! It is probably zoledronic acid

nos.org.uk/media/1597/drug-...

otherwise known as Reclast or Aclasta depending on country.

[Jamie345 in reply to Pamk1949]

They have not told me how I got multiple fractures or osteoporosis I will let you know after I've seen the rheumy I will check what's the infusion called again but was told it was the same thing I will get the results out of my file and double check name.

[Jamie345]

I'm now on 7m tapering down I've had less pain feel better in myself obviously it's still controlling my life predisinone has taken the edge/worse of the condition since this awful desease hit me approx 18 months now, but the rheumy wants me off altogether as he is not sure it is PMA and he is investigating results of more tests. Very puzzling!

[Pamk1949]

Thanks Jaime. My local rheumatologist and eye doctor don’t believe I ever had GCA as well. I just went to another city for a second opinion and they are doing tests, etc. Still I have to keep taking this prednisone and taper slowly whether I have this or not. (Temporal biopsy negative). I’m on 12 now, down from 100 mg