To expand a little on Dori’s post:
B2m is an end product of compliment activation, and ESRD patient have higher levels even before starting on dialysis. The old non-biocompatible membranes caused even higher levels, and could not remove it. High flux dialyzers cause less compliment activation, and can remove nore of it, but I have not seen any recent studies that show that dialysis patients suffer less from carpal tunnel than they did 10 years ago.
Regarding bone disease and phosphorus, it is also important to understand the effect on soft tissue, such as cardiac and blood vessels. The following is cut and pasted from an article I wrote in the Feb 2004 issue of Dialysis and Trasnplantation Magazine.
[i]To prevent bone disease and calcification of cardiac muscles, it is
important for dialysis patients to maintain the correct levels of calcium
and phosphorus in their blood. While healthy kidneys remove
excess calcium and phosphorus, it is difficult to remove phosphorus
through in-center or daily short dialysis because of its large molecular
composition. If the phosphorus level in the blood gets too high, it
causes calcium to precipitate out of the blood and be deposited in soft
tissue, such as blood vessels and heart tissue. When the blood calcium
level drops because of this precipitation, the parathyroid gland is
stimulated, causing the body to draw calcium from the bones to
replace the calcium lost from the blood. This can result in a neverending
cycle of removing the calcium from the bones, where it is
needed, and depositing it into tissue, where it is harmful.
In-center dialysis is ineffective at removing phosphorus. Using standard
dialysis to remove phosphorus is “akin to robbing a panhandler
outside of a bank rather than the bank itself.” Phosphorus is held
mostly within the cells of the body, and it takes longer than a normal
dialysis treatment to bring it into the vascular system where it can be
dialyzed. Nightly nocturnal dialysis, on the other hand, is so effective at
removing phosphorus that patients on this therapy are able to consume
much more phosphorus while requiring little to no phosphate binding
medication (Figure 2).
The calcium x phosphorus product is also reduced in patients
on nightly nocturnal dialysis (Figure 3). In fact, nightly nocturnal
dialysis often requires a higher calcium level in the dialysate,
of up to 3.5 mEq/L, and often the addition of phosphate to maintain
an appropriate calcium-phosphorus balance.[/i]
Here are the articles I cited in this section:
DeSoi CA, Umans JG. Does the dialysis prescription influence phosphate removal? Semin Dial 1995; 8(4):201-203.
Lindsay RM, Alhejaili F, Nesrallah G, Leitch R, Clement L, Heidenheim AP,
Kortas C. Calcium and phosphate balance with quotidian dialysis. Am J Kid
Dis 2003; 42(1, Suppl 1):S24-S29
Lockridge RS, Anderson HK, Coffey LT, Craft VW, Jennings FM, McPhatter II, Spencer MO, Swafford AC. Nightly home hemodialysis in Lynchburg, Virginia: Economic and logistic considerations. Semin Dial 1999; 12(6):440-447.
Pierratos A. Nocturnal home haemodialysis: An update on a 5-year experience. Nephrol Dial Transplant 1999; 14:2835-2840.
There is a test I have heard about at conferences called the Electron Beam Computed Tomography (EBCT) that can measure calcium deposits in soft tissue. Those studies have show that there are significant deposits in most dialysis patients within one year of starting dialysis. I have not seen any studies on patients undergoing daily dialysis.