Diabetes Educators Express Report

American Association of Diabetes Educators 33^rd Annual Meeting, August 9, 2006, in Los Angeles, California

Publication date: 2006-10-01

Strategies for Early Identification and Treatment of Complications Associated with Chronic Kidney Disease

This report was reviewed for medical and scientific accuracy by Abigail Zavod, MD, MPH, Senior Staff Physician, Lahey Clinic, Burlington, Massachusetts.

Introduction

Chronic kidney disease (CKD) is a worldwide epidemic; approximately 20 million Americans have some stage of CKD.¹ The number of individuals with end-stage renal disease is projected to increase from 340,000 in 1999 to 651,000 by 2010. ¹ Major outcomes of CKD include progression to kidney failure, complications of decreased kidney function, and cardiovascular disease which results in significant morbidity and mortality. Indeed, the risk of death substantially increases with the progression of CKD. ^2,3

Diabetes is the most common primary diagnosis in patients with kidney failure; ⁴ 45% of patients with CKD stage 5 have a primary diagnosis of diabetes. Aggressive intervention is warranted both to prevent diabetes and slow the rate of CKD progression in those diagnosed with diabetes.

There is a growing body of evidence to indicate that early stages of CKD are associated with disruption of the active vitamin D-parathyroid hormone axis. This disruption leads to secondary hyperparathyroidism (SHPT) and sub-sequent high rates of bone and cardiovascular disease common to later stages of CKD. ⁵ Increasing evidence suggests that adverse outcomes associated with CKD can be prevented or delayed by early detection and treatment. ⁶ Early stages of CKD can be detected through routine laboratory measurements.

Several laboratory values are used to assess kidney function. The measurement of serum creatinine is often used to assess kidney function. ⁷ Many studies support the similarity of creatinine clearance to glomerular filtration rate (GFR) and its reciprocal relationship with the serum creatinine level. ^8,9 However, a major limitation to this practice is that the relationship between levels of serum creatinine and GFR varies substantially among individuals and over time. As a consequence, serum creatinine lacks sensitivity in determining the onset of nephropathy-a critical juncture where kidney function is most sustainable by early intervention (eg, dietary and pharmacologic treatment). ^7,10,11

The GFR is accepted as the best overall measure of kidney function. ^12,13 Therefore, assessment of GFR is critical for the early identification of CKD. Two estimating equations for GFR have been extensively studied and widely applied primarily for patients with CKD and reduced GFR-the Cockcroft-Gault equation¹⁴ and the Modification of Diet in Renal Disease (MDRD) equation. ¹⁵ The MDRD equation, which takes into account ethnicity, race, gender, age and serum creatinine levels, has been adopted by the National Kidney Foundation (NKF) for use in its online GFR calculator. ^10,11

This Diabetes Educators Express Report^TM reviews the strategies for early identification and treatment of complications associated with CKD presented during a satellite symposium held during the American Association of Diabetes Educators 33^rd Annual Meeting, August 9, 2006, in Los Angeles, California.

eGFR: A More Reliable Tool for Early Screening

“Chronic kidney disease is a growing epidemic and diabetes is the most common primary diagnosis in patients with kidney failure,” according to Anne Daly, MS, RD, BC-ADM, CDE, Director of Nutrition and Diabetes Education, Springfield Diabetes and Endocrine Center, Springfield, Illinois. ¹⁶ Furthermore, nearly 20 million adults in the United States are in various stages of CKD (defined as GFR <60 mL/min/1.73 m² of body-surface area or the presence of kidney damage, regardless of the cause, for three or more months^4,17,18) (Table 1).

Ms. Daly emphasized that any degree of renal dysfunction increases the risk of cardiovascular disease^2,