RenalWEB links to an interesting study in Nephrology Dialysis Transplantation Japanese haemodialysis anaemia management practices and outcomes (1999–2006): results from the DOPPS, the full text is available. There is a lot to take away from this research paper.
One thing I didn't know was the impact the body's position has on hemoglobin levels. Apparently if you draw a blood sample while an individual is lying down the hemoglobin will tend to be lower than if you draw the sample while the individual is seated. This implies a fairly rapid movement of fluid to the vascular fluid compartment from the fluid compartment between the cells - which would explain why the trendelenburg position works. Also drawing the sample on the first run of a three run week will result in lower hemoglobins than if the result is drawn during a later run in the week. In Japan most samples are drawn on the first run of the week and most people are lying down when the sample is drawn. As the paper discusses:
An extrapolation from the JSDT anaemia guideline paper[11] suggests that a target of 10–11 g/dl in Japan may be equivalent to a target of ~10.7–11.7 g/dl in another country measuring Hb levels in a seated position and during a mid-week session.
Another nugget in the paper is the graph showing the distribution of hemoglobins among the study population and facilities. I think if you shifted the distribution to the right to account for how the samples were taken you'd see a distribution very similar to the US hemoglobin distribution - post 11/2006 when changes were made to the US Epo reimbursement guidelines. It isn't just the target range that matters, it is what happens to reimbursement if the target range is exceeded. In the US rules that would withhold payment for going too far above the target would tend to shift the entire distribution to the left. New rules including epo in an expanded payment bundle would also tend to shift the distributions to the left. I think a comparison of US and Japanese hemoglobins in 2009 (assuming an expanded bundle) will show that they are about the same without any change in practice on the part of the Japanese.
Where the US and Japan don't match up is in the amount of EPO used per person and the mortality risk of being on dialysis. Japan uses far less EPO - a mere 6,300 units per week compared to I would think 24 or 25,000 units per week in the US. The Japanese mortality rate is the best in the world, below 10%, while the US dialysis mortality rate is the worst in the world, stubbornly above 20%. Is there a connection?
I would expect there to be a common thread: dose of dialysis per kilogram of body weight. All else being equal (case mix adjustment) I would expect those receiving more minutes of dialysis per kilogram to have better mortality outcomes and need less EPO - the Japanese results. It would be interesting to see the DOPPS data on the body weight distribution of people on dialysis and the per kilogram treatment time in the participating countries. My expectation would be that Japan has the highest per kilogram treatment times. If we had a betting pool I would wager on 4 - 5 minutes per kilogram per treatment in Japan vs. 2 to 3 minutes per kilogram per treatment in the US.
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