The Achilles Heel of Mortality Risk by Dialysis Modality is Selection Bias

Author:
Open Access
Publisher website
Google Scholar
Abstract
Beneficial effect of increased treatment time on IDH is more than might be anticipated because of the logarithmic relationship between UFR and IDH: A small increase in time yields a proportionately greater decrease in IDH. 12 In addition, the reduction in UFR by itself may reduce mortality risk. 13 We write decreasing dietary sodium rather than focus on interdialytic fluid intake to emphasize two points. First, dietary sodium drives fluid intake and weight gain in most patients. Ignoring fluid restriction and concentrating on sodium intake more effectively reduces weight gain than does restricting both-illogical, but perhaps patients just give up from all their dietary restrictions. 14 The second reason for emphasizing dietary sodium is that weight gain as a result of primary fluid intake, recognized by predialysis hyponatremia, is far easier to remove without IDH than a similar isonatric fluid load because diffusive sodium gain supports extracellular volume. 15 Finally, increasing dry weight is really the default action taken to treat IDH. We may not order it, but patients override us with their low BP. The increased weight expands interstitial volume; the larger this space is, the faster it can be mobilized to replace ultrafiltrationinduced declines in plasma volume. 16,17 Unfortunately, volume expansion is undesirable and adversely affects mortality. 18 The list of adverse consequences from IDH keeps growing. VAT is but one more reason to be concerned about what IDH does to our patients. We can dance around the edges of the problem but it is going to take a change in our traditional thrice-weekly HD regimen to fix it. DISCLOSURES None. Since the introduction of ambulatory peritoneal dialysis (PD) in the late 1970s, several investigators have attempted to compare the risk of death between patients treated with PD and those treated with hemodialysis (HD). Clearly, the ideal study design to examine this question would be a ran

This publication has 34 references indexed in Scilit: