Blog entry by Denise Smith
I take the opportunity of this Nephron Digest to let you know that I have now completed my term as Editor of Nephron Clinical Practice.
It has been a great, enjoyable and challenging journey promoting a great journal and reaching for a broader readership.
I hope you enjoyed reading the Nephron Digests and continue to read and follow Nephron. The new Editor of Nephron Clinical Practice is Professor David Wheeler, Reader in Nephrology at University College London, London, UK. I have no doubt that under his stewardship and the guidance of Professor Leon Fine (Chief Editor of Nephron), Nephron Clinical Practice will continue to forge ahead and raise its global profile.
Professor Meguid El Nahas, PhD, FRCP
Editor, Nephron Clinical Practice
Association of Deprivation with Worse Outcomes in Chronic Kidney Disease: Findings from a Hospital-Based Cohort in the United Kingdom (M.P. Hossain, D. Palmer, E. Goyder and M. El Nahas, Sheffield; Nephron Clin Pract 2012;120:c59-c70) The authors report that area level low socio-economic status (SES) is associated with both heavy proteinuria at presentation and rapid progression of CKD. Unskilled professionals were also found to have a marginally significant association with increased risk of mortality. People living in more deprived areas presenting with CKD are likely to be at increased risk of poor outcomes and may need more active management and earlier referral. Such increased risk is likely to be more acute in emerging countries where late referral of CKD patients is a major nephrological healthcare challenge. Most patients who start RRT in these countries are seen within less than 3 months from initiation of therapy. That is the real challenge of CKD in emerging economies, not the early detection and prevention of CKD1 and 2, but the timely referral of CKD3!
Disappearance of Association in Diabetic Patients on Hemodialysis between Anemia and Mortality Risk: The Japan Dialysis Outcomes and Practice Pattern Study (M. Inaba and colleagues, Kyoto and Tokyo; Nephron Clin Pract 2012;120:c91-c100) Inaba and colleagues report a significant association between hematocrit with all-cause mortality in non-diabetic ESRD patients after adjustment for age, gender, BMI, hemodialysis duration, SBP, DBP, albumin, total cholesterol, calcium, phosphorus, and intact PTH. This association disappeared in diabetic patients suggesting that the association between anemia (lower hematocrit) and higher mortality disappeared in DM hemodialysis patients, in contrast with non-DM counterparts. Once more, an observational study highlights the fact that the higher the hematocrit, the better in terms of outcomes and survival in HD patients. This has not been confirmed by randomized clinical trials when raised hematocrit beyond a certain level (around 36%) has been associated with increased cardiovascular risk. Hence guidelines defining target hematocrit for HD patients between 33 and 36%. However, guidelines do not take into consideration the complexity and heterogeneity of HD patients, as they don't distinguish for instance between diabetic and non-diabetic patients, or young and older patients, and as shown in the paper by Inaba et al., different hematocrit targets may have different implications according to underlying comorbidities.
Non-Calcium-Containing Phosphate Binders: Comparing Efficacy, Safety, and Other Clinical Effects (J.M. Frazao and T. Adragao, Lisbon; Nephron Clin Pract 2012;120:c108-c119) The authors review the potential of non-calcium-containing phosphate binders in patients with CKD. They conclude that sevelamer and lanthanum carbonate are effective at reducing serum phosphorus levels to those recommended by international guidelines. They also suggest from a small number of studies that sevelamer (Renagel) may have therapeutic advantages in terms of reducing vascular calcifications. This was suggested in the RIND (Renagel in New Dialysis) and TTG (Treat to Goal) studies but not by others such as BRiC and CARE2. Such analysis is of considerable interest and highlights a number of issues: First, the jury is out on the superiority of Renagel over calcium-containing phosphate binders in terms of vascular calcifications. Second, the use of vascular calcifications as surrogate endpoint may be subject to analytical confounders and variability and does not negate the need for hard end-points such as major adverse cardiovascular events (MACE) or more importantly, mortality. Of interest, in that respect, in the DCOR study, in 12,100 chronic hemodialysis patients, there was no difference in all-cause mortality between sevelamer and calcium-based phosphate binder therapy over a 3-year observation time. Third, as often in nephrology, smaller clinical trials and observational studies tend to show promising effects of interventions that are all too often disappointed by larger studies. Fourth, a cost analysis is needed to support the cost:benefit of non-calcium-containing binders, including sevelamer. As so often in nephrology, tempered enthusiasm is warranted for newer agents compared to older ones, but enthusiasm should not replace critical analysis of available evidence as well as the requirement for hard and meaningful clinical endpoints. These remain lacking to favor newer phosphate binders.