Overview of Chronic Kidney Disease and ESRD

Overview of Chronic Kidney Disease and ESRD Gordon McLennan, MD Conflicts & Acknowledgments Member, Board of Trustees, The Renal Network Inc. Grant Support – Boston Scientific Corporation – Omnisonics Medical Technologies – Cook, Inc. – W. L. Gore, Inc. – Arrow International Take Home Message CKD represents a much larger problem than ESRD Use of calculated GFR to assess renal function will help us identify patients at risk for ESRD It is incumbent on us to identify patients who can have fistulas placed at stage 3 & 4 CKD Chronic Kidney Disease & ESRD ESRD (Renal Failure affects only about 400,000 Americans Chronic Kidney Disease affects 8 Million Chronic Kidney Disease Glomerular filtration rate (GFR) <60mL/min/1.73m2 for >3 months with or without kidney damage OR Kidney damage for >3 months, with or without decreased GFR, manifested by either – Pathologic abnormalities – Markers of kidney damage, eg, proteinuria Affects 11% of US popluation CKD Stage Description GFR mL/min/1.73 m2 Prevalence N (1000’s) % 0 1 At increase risk of CKD Kidney damage w/ normal or ↑ GFR > 90 > 90 20,000 5,900 11.2 3.3 2 3 4 5 Kidney damage w/ mild ↓ GFR moderate ↓ GFR severe ↓ GFR Kidney Failure 60-89 30-59 15-29 <15 or dialysis 5,300 7,600 400 300 3.0 4.3 0.2 0.1 Stages 0-4 NHANES III 1988-1994 Stage 5 USRDS 1998 Co-morbidities of CKD 50-500 x mortality Predominant cause is CVD Foley RN, Parfrey PS, Sarnak MJ: Clinical epidemiology of cardiovascular disease in chronic renal disease. Am J Kidney Dis 32:S112-S119, 1998 (suppl 3) Incidence of End Stage Renal Disease (ESRD) According to Primary Diagnosis USRDS. 2004. Available at: http://www.usrds.org/atlas.htm. Co-Morbidities of the ESRD Population 80% of dialysis patients who have an MI are dead within 3 years Herzog CA, Ma JZ, Collins AJ: Poor long-term survival after acute myocardial infarction among patients on long-term dialysis. N Engl J Med 339:799-805, 1998 Life Expectancy Patients Diagnosed with CKD ± DM Have a Greater Likelihood of Death than ESRD First nephrologist visit at an outpatient clinic (n=20,363) Percent of patients (%) 100 80 60 n=11,698 3,637 2,884 2,144 No Events ESRD Death 90.33 83.75 68.24 11.34 60.73 40 20 0 17.58 21.60 8.27 12.40 20.42 NDM/Non-CKD DM/Non-CKD NDM/CKD DM/CKD Status in the entry period CKD Principle #1 There are close to 20 million patients in the U.S. with CKD stages 1-5. There are perhaps another 20 million patients in the U.S. at risk for CKD – Many of these patients are not under a physician’s care, so targeted screening of at-risk populations is costeffective – For those patients under a physician’s care (usually a PCP), most of the CKD interventions can and should be delivered by the PCP – Early referral of a CKD patient to a nephrologist (when GFR <60 ml/min/1.73m2) to provide strategic guidance is associated with improved outcomes GFR Serum Creatinine is not very predictive of renal function GFR affected by age, gender, weight, & race Formulas exist to estimate GFR that are more accurate than 24 hour urine collection MDRD – GFR (mL/min/1.73 m2) = 186 x (Scr)-1.154 x (Age)-0.203 x (0.742 if female) x (1.210 if African American) Crockroft-Gault – – For men: CrCl = [(140 - Age) x Weight (kg)]/SCr x 72 For women: CrCl = ([(140 - Age) x Weight (kg)]/SCr x 72) x 0.85 GFR Lin J, Knight EL, Hogan ML, Singh AK: A Comparison of Prediction Equations for Estimating Glomerular Filtration Rate in Adults without Kidney Disease. J Am Soc Nephrol 14: 2573–2580, 2003 50 y/o AA Female referred from Family Practitioner for renal arteriography because of uncontrolled hypertension Significant history: Type 2 DM & Hypertention Serum Cr 1.4 What would you do? – – – – – – MRA Hydrate overnight Bicarb N-Acetyl Cystine Use alternative contrast agents Nothing special—Do arteriogram & limit contrast as much as possible Calculated MDRD GFR GFR (mL/min/1.73 m2) = 186 x (Scr)1.154 x (Age)-0.203 x (0.742 if female) x (1.210 if African American) GFR = 186 x 1.4-1.154 x 50-0.203 x 0.742 x 1.210 51 CKD Principle #2 Use of serum creatinine as a marker of kidney function grossly underestimates the presence and severity of CKD – Formulas for GFR (MDRD) or creat. clearance (Cockcroft-Gault) are more sensitive, easy to use and do not require 24 hour urine collection – 24 hour urine collection for creat. clearance is notoriously inaccurate – All labs should be encouraged to report renal function as GFR based on MDRD formula (age, gender and race) Optimal CKD Patient Care Early Detection of CRF Interventions that delay progression ACE inhibitors BP control Prevention of uremic complications Malnutrition Anemia Osteodystrophy Acidosis Modification of comorbidity Cardiac disease Vascular disease Preparation for RRT Education Informed choice of RRT Timely access placement Timely initiation of dialysis Blood sugar control Protein restriction Neuropathy (in diabetics) Retinopathy (in diabetics) Assessment for Renal Replacement Therapy Transplant Peritoneal Dialysis Hemodialysis – AVF – Graft Synthetic Material Biological Material (Bovine Carotid Artery) – Catheter Fistula First CMS, the ESRD Networks, the renal community, and IHI will work together to increase the likelihood that every eligible patient will receive the most optimal form of vascular access for that patient. In the majority of cases, this will be a fistula. Incident Patients Prevalent Patients NVAII Goals By June 2006 – 40% prevalent fistulas – 50% incident fistulas By June 2009 – 66% prevalent fistulas NVAII Change Concepts 1. Routine CQI review of 2. 3. 4. 5. 6. AVF placement in vascular access Early referral to nephrologist Early referral to surgeon for ―AVF only‖ Surgeon selection Full range of appropriate surgical approaches catheter patients 7. Cannulation training 8. Monitoring and surveillance 9. Continuing education: staff and patient 10.Secondary AVFs in AVG patients 11.Outcomes feedback Algorithms Venography or ultrasound in all catheter & graft patients – Look for conversions Algorithms to evaluate veins at Stage 3 & 4 – Physical Exam – Ultrasound – Venography where needed AVF Types Take Home Message CKD represents a much larger problem than ESRD Use of calculated GFR to assess renal function will help us identify patients at risk for ESRD It is incumbent on us to identify patients who can have fistulas placed at stage 3 & 4 CKD