Dialysis, calcium and phosphate binders

[okarol]

Dialysis, calcium and phosphate binders
dialyblog | May 29, 2011 at 6:48 pm | Categories: Uncategorized | URL: http://wp.me/puMEh-aU

One of the fun things that happen when two or three BigD members gather together for coffee or a meal is the phosphate binder ritual: all hands dip into pockets to find calcium pills, into the mouth, swallow with a sip of water and its back to the conversation.

We all do it, but I know it took me a while to understand why.  Just recently we had an in-house briefing about it at our dialysis unit from the very excellent Cath F, so I thought I’d share what was said.  (The good stuff is hers, any mistakes are mine.)  Thanks Cath.

It is all to do with ensuring that our calcium levels remain high enough to keep our bones and muscles strong and healthy.  I have often thought that my body is just a big bag of chemicals.  If all the chemicals are in balance, I feel fine and can take on the world.  If the chemicals are out of balance, I’m not worth talking to.

In the case of calcium (and its evil brother phosphate), it is very much getting the mix right.  In the normal course of events, we eat foods with calcium and phosphate (and many other things).  The calcium and phosphate travel to our stomach, where the right amounts are absorbed into the bloodstream and the rest flushed away via the bowel.

Guess which organs regulate the level of calcium and phosphate in the bloodstream?  You got it, the kidneys (with the liver).  They do this by producing a hormone called Calcitriol, or activated Vitamin D.  Calcitriol also controls another organ group, the parathyroids, four glands the size of a grain of rice in the neck, surrounding the Adam’s apple.  These control how much calcium is in our bones, and how much calcium is in our blood.

But for BigD members, it’s a little different.  Without the kidney producing the Calcitriol to control how much phosphate and calcium gets into the bloodstream, the gates are wide open.  That’s when the evil brother takes over.  All those extra phosphate molecules in the bloodstream attract and combine with the calcium, quickly causing a calcium shortage.  The parathyroids identify the shortage and instruct the body to release more calcium from our bones.  The phosphate combines with that calcium too and the parathyroids calls for more calcium, and so on in a vicious cycle until our bones become porous and fragile.  Bad news all around.
There are several actions we can take to prevent this.

Firstly, we can replace the Calcitriol that our kidneys no longer produce with artificial Calcitriol (in little red and white football-shaped pills) that performs the same function.  The level required varies and most people have a regular blood test (typically monthly) to track and manage it.  I take four every Thursday.  The level sorts itself out over the week.

Secondly, we can slow the operation of the parathyroids.  These days this is done with a drug called Sensipar® (or Mimpara®), that mimics a high calcium level for the parathyroids.   It stops them sending those "send more calcium" signals to our bones.  Before this drug, we used to have a small surgical procedure to remove some or all the glands.  I am in this "before" group.  You can tell who we are: we all have a nice white line below our Adam’s apple (indicating that we are all members of the BigD Parathyroid Subcommittee).

Thirdly and most commonly, we can take phosphate binders. These work pretty simply: you take at least one just before you have food or drink that has phosphate in it (just about everything has phosphate!).  The pill sits in your stomach and unravels into liquid.  As the phosphate-rich food arrives, it floats in the calcium liquid, and the phosphate binds with the calcium.  The joint phosphate-calcium molecules are then carried through the gut, into the bowel and out into the cold hard world again.

Pretty-well everyone’s monthly blood tests include phosphate levels, so it’s pretty easy to keep track.
I take about two 600mg Caltrate (calcium carbonate) tablets and one 750mg Fosrenol (lanthanum) chewable tablet as phosphate binders before meals.

Over the last few months mine have been stubbornly high, and I have the itches and aches to prove it.  However I recently increased my Calcitriol dose and I think things are improving.
The other technique of course is to cut the phosphate-rich food you put in your mouth.  I made the mistake about 6 months ago of going onto Soymilk.  I thought (without doing any research) that it must have lower phosphate than cow’s milk – seems logical, right?  Every week I got itchier and every month my phosphate level got higher.  I doubled my phosphate binders and it was still high.

Finally I spoke to our unit's dietician and she told me the awful truth: soymilk is VERY high in phosphate.  And I was having a great dose on my cereal every morning!  So I asked the obvious question: what should I be having?  The answer surprised me: Rice milk - low in phosphate and quite tasty (though rice milk on rice bubbles seems a little one-dimensional).  Still, the result has been impressive: my phosphate is nearly normal.

So next time you get together for coffee, don’t forget the ritual.  Do it early and do it often, and keep your bones healthy.

Blog post from "Big D and Me" http://bigdandme.wordpress.com/2011/05/29/dialysis-calcium-and-phosphate-binders/

[galvo]

Interesting article.

[greg10]

Dialysis, calcium and phosphate binders
dialyblog | May 29, 2011 at 6:48 pm | Categories: Uncategorized | URL: http://wp.me/puMEh-aU..

Secondly, we can slow the operation of the parathyroids.  These days this is done with a drug called Sensipar® (or Mimpara®), that mimics a high calcium level for the parathyroids.   It stops them sending those "send more calcium" signals to our bones.  Before this drug, we used to have a small surgical procedure to remove some or all the glands.  I am in this "before" group.  You can tell who we are: we all have a nice white line below our Adam’s apple (indicating that we are all members of the BigD Parathyroid Subcommittee)...

Finally I spoke to our unit's dietician and she told me the awful truth: soymilk is VERY high in phosphate.  ..

Blog post from "Big D and Me" http://bigdandme.wordpress.com/2011/05/29/dialysis-calcium-and-phosphate-binders/

A couple of points on this good article.

1.  Those who take sensipar may want to consider taking it a few hours ahead of their dialysis in order to prevent a spike in parathyroid production in response to the lower calcium levels in the dialysate during dialysis.  This seems to help in lowering the overall dosage of sensipar.

2. Those patients doing extended duration dialysis will generally have less phosphorus restriction due to the higher efficiency of phosphorus (and other middle molecules) removal.  Some nocturnal HD patients have no phosphorus restriction or even have too low levels of phosphorus.  Know your HDP (hemodialysis product, Scribner, B. H. and D. G. Oreopoulos (2002). "The Hemodialysis Product (HDP): A Better Index of Dialysis Adequacy than Kt/V." Dialysis & Transplantation 31(1).)
   http://www.therenalnetwork.org/qi/resources/HDP.pdf

3.  Soy milk is not naturally high in phosphorus.  It is a matter of additives and reading the labels. (see attached nutrient contents of soy milk).

[Marina]

3.  Soy milk is not naturally high in phosphorus.  It is a matter of additives and reading the labels. (see attached nutrient contents of soy milk).

Greg,
Soy  products  are  extremey  high in  phosphorus.           Therefore  Soy milk  is or  can  be  higher,  due  to  all the  added  nutrient  contents.
It's  always  a  good  idea  to check  with  dietitian  before  using  any  soy  products.

[boswife]

This is my kind of reading.  PERSONAL type that is   When a real person/people are talking about stuff, it makes it not only more interesting, but so much more understandable... IMHO that is 

[aharris2]

3.  Soy milk is not naturally high in phosphorus.  It is a matter of additives and reading the labels. (see attached nutrient contents of soy milk).

Greg,
Soy  products  are  extremey  high in  phosphorus.           Therefore  Soy milk  is or  can  be  higher,  due  to  all the  added  nutrient  contents.
It's  always  a  good  idea  to check  with  dietitian  before  using  any  soy  products.

As Greg10 said, soy milk is not naturally high in phosphorus. Take charge, always read labels!

[greg10]

Hi Marina.  You are right in that in general, soy products have high phosphorus, just as milk products have high phosphorus content.  However in modern manufacturing processes, the protein isolates are filtered or precipitated, such as soy protein isolate and whey protein isolate, such that the end products are very protein rich isolates that had much of the phosphorus washed off in the effluent.  Therefore you can have soy milk that has about 100mg of phosphorus per cup or whey protein isolates that has about 125 mg per 30 g serving, which is considered generally as acceptable in moderation.  You may have to watch out for excessive mineral additives such as calcium in some soy milk formulation, so always read the label and check twice because the labels can be wrong. 

http://nutritiondata.self.com/facts/legumes-and-legume-products/8010/2

3.  Soy milk is not naturally high in phosphorus.  It is a matter of additives and reading the labels. (see attached nutrient contents of soy milk).

Greg,
Soy  products  are  extremey  high in  phosphorus.           Therefore  Soy milk  is or  can  be  higher,  due  to  all the  added  nutrient  contents.
It's  always  a  good  idea  to check  with  dietitian  before  using  any  soy  products.

[Rerun]

Watch for the word "ENRICHED".  Even in the rice milk get the "Original Classic" not the Enriched.

[Bruno]

Very interesting comments because I recently had a phosphate problem (over 4) which indicated that my caltrate binder was no longer working well. I also noticed my itches were slightly worse so I thought it might have been my switch to soy milk but listening to what you are saying...maybe not?
Anyway, I gave up soy but that's not the end because my neph put me on a new phosphate binder called Renagel (costs a bomb here in Oz) and I just saw my last bloodwork and it's pulled my phosphate levels back to normal again.
So I live to fight another day.

[greg10]

Very interesting comments because I recently had a phosphate problem (over 4) which indicated that my caltrate binder was no longer working well. I also noticed my itches were slightly worse so I thought it might have been my switch to soy milk but listening to what you are saying...maybe not?
Anyway, I gave up soy but that's not the end because my neph put me on a new phosphate binder called Renagel (costs a bomb here in Oz) and I just saw my last bloodwork and it's pulled my phosphate levels back to normal again.
So I live to fight another day.

Hey Bruno, I hear you about the cost of new phosphate binders such as Renagel and Fosrenol (Lanthanum carbonate).  We find that it is actually cheaper and better to do longer (extended) hemodialysis and obtain the benefits of using little or no binders than to have to pay and put up with the side effects of the binders.  I understand extended dialysis may not be practical or available to everybody.

Please be aware that there are many different formulation of soy milk and there is no "standard" soy milk such as you can have regular cow's milk. I would stay away with any traditional soy milk such as you get at an Asian food store because you are less likely to get a modern preparation that has reduced phosphorus.  Also watch for excessive calcium and sugars additives.

[Alisa]

Upset no one told me about the drug Sensipar® (or Mimpara).  I had my parathyroids removed and now have had nothing but calcium and potassium problems.

[greg10]

Upset no one told me about the drug Sensipar® (or Mimpara).  I had my parathyroids removed and now have had nothing but calcium and potassium problems.

I am sorry to hear about the side effects of your parathyroidectomy, but I understand it is fairly common.  Sensipar or Cinacalcet as it was first described in studies funded by the National Science Foundation (US), is an effective treatment for high PTH but unfortunately it is not indicated for pre-dialysis patients.  The drug is quite expensive, from $500 to $1500 per month and unfortunately no generic form will likely to be available until 2014.  I find it incomprehensible that a drug first characterized mainly through US public funding is now having the rewards reaped by private corporations and most of the costs paid through the US public funded health care system of Medicare and Medicaid.

http://dailymed.nlm.nih.gov/dailymed/archives/fdaDrugInfo.cfm?archiveid=4733

[Treasure]

I am soooooo glad I had a parathyroidectomy last October. My PTH was not controlled by Sensipar (even upping the dosage to the maximum)...and Sensipar made me throw up all the time (much like Fosrenol...that combination should maybe be a new weightloss remedy hehehe...j/k). I could not get a doctor to approve the surgery in California, but got to work on it as soon as moved to Texas a few months ago, and having that surgery made all the difference in the world.

[Bruno]

Greg, what do you mean by 'extended dialysis'? I'm currently doing 24 hours per week (4 sessions each of 6 hours) so I'm interested in your thoughts.

[Zach]

Greg, what do you mean by 'extended dialysis'? I'm currently doing 24 hours per week (4 sessions each of 6 hours) so I'm interested in your thoughts.

Is that nocturnal hemodialysis?

[tyefly]

Now that I am doing nocturnal   or  extended   dialysis  my labs are great....  phos is way down and potassium is way down too... I drink and eat what ever I want.... I take no binders...  I do 40 hours of dialysis a week.... just sleep right thru it.....  Before I started nocturnal.... my phos was always in the 5's  and I was taking 9 binders a day...