Thursday, April 12, 2012

Dialysis Unplugged: READ ALL ABOUT IT – MORE DIALYSIS IS BETTER

A number of people have chastised me for demanding, in my articles, that we need more evidence to prove the superiority of frequent daily or nocturnal dialysis over conventional dialysis. In fact, I’ve agreed to participate in a debate in NDT about this very issue.

So let me state for the record that I am a believer in more dialysis. If a family member or I was on dialysis I would opt for more frequent dialysis. And, I recommend home dialysis to my patient’s as they embark on dialysis. Yes, I am a believer.

But I do feel that we need more data. I really do feel that we have not reached that point, described by Malcolm Gladwell in his famous book, of tipping the majority to agree that more dialysis is better.

To reach the tipping point we need a fairly large randomized controlled trial, properly powered and evaluating the effect on hard end-points like mortality and cardiovascular complications. Besides, demanding for more evidence isn't that unreasonable - we all know that there is enough money in the dialysis industry to fund such a trial. After all, DaVita made over 3 billion in profit. Worse, Kent Thiry DaVita’s CEO made over 13 million dollars in compensation. The situation is similar at Fresenius I am sure.

We have gone as far as we can – short of a randomized trial – to establish the superiority of more dialysis. 

Take for example a study published in the current JASN. [One of the renal fellows had printed it over the weekend]. It's a nice study, well worth reading. Nesrallah and co-workers from London Ontario performed a analysis comparing outcomes in patient’s undergoing intensive versus in-center hemodialysis.

Nesrallah and co-workers identified 420 patients in the International Quotidian Dialysis Registry who received intensive home hemodialysis in France, the United States, and Canada between January 2000 and August 2010. They matched 338 of these patients to 1388 patients in the Dialysis Outcomes and Practice Patterns Study who received in-center conventional hemodialysis during the same time period by country, ESRD duration, and propensity score. The use of matching using propensity scores was targeted to attenuate the effect of confounding. The investigators also performed several sensitivity analysis to test the strength of their findings. Obviously one of the major limitations of the study is that they couldn't achieve perfect balance between the two groups (intensive vs. conventional HD) and they couldn't eliminate the potential effect of residual confounding.

The bottom-line: 13% receiving intensive hemodialysis died compared with 21% receiving conventional hemodialysis (6.1 versus 10.5 deaths per 100 person-years; hazard ratio, 0.55 [95% confidence interval, 0.34–0.87]). As well, patient’s undergoing intensive dialysis had better metabolic control.