Thursday, October 6, 2011

SLE and Dialysis

It is well known that patients who are referred to see a nephrologist earlier in the course of their disease are more likely to start dialysis with a functioning fistula and have better overall survival relative to those who are referred <12 months before starting dialysis. The care of many of these patients in the period before starting dialysis often involves doctors from multiple specialties and this is particularly true in patients with vasculitides and rheumatological diseases who are commonly co-managed by rheumatologists and nephrologists. What happens to these patients after they start dialysis?
Looking specifically at SLE, the feeling has been in the past that in a patient with lupus nephritis, after they go onto dialysis, their lupus burns out. In most cases, immunosuppression is reduced significantly or stopped. These patients are coming into their local dialysis unit 3 times weekly and because of this time commitment, they may be less likely to follow-up with other doctors that they might have attended during their pre-dialysis days. However, at least one study has shown that patients with SLE who start dialysis have a worse overall prognosis than matched controls.
A study was recently published in the Journal of Rheumatology that looked at patients with SLE after they start dialysis. They found that patients who saw a rheumatologist 2 or more times yearly following initiation of dialysis had improved overall mortality relative to those who attended less that twice yearly. One of the major differences between the groups was that patients who attended a rheumatologist more often were more likely to have continued on immunosuppressive therapy after starting dialysis. Specifically, patients who were taking hydroxychloroquine had a lower mortality independent of whether or not they received a renal transplant. The potential benefits of hydroxychloroquine are not just related to the immunosuppressive effects of the drug but it also appears to decrease thrombotic events and has a favorable effect on lipid profiles. There is increasing evidence that SLE remains active in the time after starting dialysis and that not treating this may be detrimental. Nephrologists need to be aware that SLE does not go away completely when a patient starts dialysis and we need to get better at recognizing the extra-renal manifestations of SLE so as not to allow these symptoms and signs to get lost amid the overall noise caused by being on dialysis itself.
This study was flawed. It is a small observational study with a large number of potential confounders. The patients who rarely saw a rheumatologist prior to initiation were also less likely to have followed up closely prior to initiation. There were likely other factors influencing their follow-up that may also have influenced their overall mortality. However, it does raise some interesting questions and suggests that we should be thinking again about the more routine use of hydroxychloroquine in this population.

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