Blog entry by Meguid El Nahas
I am attending the Annual meeting of the Egyptian Society of Nephrology and Transplantation (ESNT) in Marsa Alam, Egypt.
On the 13 and 14 of February and Pre Congress CME meeting is held.
On day 1 of the CME meeting, I attended a lecture by Professor Richard Glassock, USA, in which he discussed arguments related to the timing of the initiation of renal replacement therapy. He showed very elegantly in his lecture how timing of starting dialysis has evolved over the last 30 years from those who in the 70s and 80s advocated early start of RRT at GFR levels of around 15 to 20 ml/min to those morte recent observations arguing that late start of HD may be more beneficial.
A number of reviews and analysis concluded that there was little advantage in starting RRT too early; GFR>15 ml/min.
Professor Glassock referred to his work and that of Rosansky (2010) showing that those starting HD at the highest quartile of eGFR (>15) had the highest mortality. Of interest, this was more specifically evident in those with higher GFR and serum albuminlevels >35g/l. He also referred to the IDEAL study by Cooper et al (2009).
Prof Glassock explained the possible confounder of the interpretation of such observation with emphasis on the value of low serum creatinine as a marker of somatic malnutrition whilst changes in serum albumin are more reflective of visceral malnutrition. Sarcopenia and wasting may therefore explain some of the observations linking poor outcomes to early initiation of HD based on calculated GFR derived from equations such as the MDRD.
He also stressed the poor performance (imprecision and bias) of the MDRD formula in CKD stage 5. In fact, he showed data that eGFR calculated in CKD5 by such an equation considerably overestimates measured GFR. He suggested that the average of creatinine + Urea clearance may be a more accurate way of measuring GFR at this late stage of CKD.
It is also important to consider that timely referral of CKD4-5 patients to pre-dialysis care clinics and optimal preparation for RRT ar eas important in relation of the overall care of the CKD5 patient than the timing of the initiation of dialysis. Early referral to nephrologists is often not the case with patients presenting late and ill prepared for RRT. The setting up of pre-dialysis/low clearance clinics has been avocated in the UK to optimise the pre-RRT care of CKD patients. Optimal pre-ESRD care leads in many cases to prolong period of stable kidney function between eGFR of 10 and 15ml/min in asymptomatic patients. Many of the symptomas of these patients are alleviated by good anemia control as well as good control of their calcium and phosphorus metabolism as well as attention to their nutritional requirements. Pre dialysis clinics also allow for a better planning of vascular access as well as consideration/investigations for renal transplantation. Finally, good pre dialysis care involves social and psychological counselling for the patient and his family.
* See Review by Mustafa Arici in the OLA Libray on Timing of Start of RRT.