Identifying Chronic Kidney Disease (CKD)

Advantages and Pitfalls of the Current Classification System

Risk Factors

Costs of CKD

End of Life

Mark D. Purcell DO Nephrology/Internal Medicine

Carolina Nephrology, PA

203 Mills Avenue

Greenville, SC 29605

(864) 271-1844

mpurcell@mykidneydoc.com

Objectives

Identify patients with chronic kidney disease (CKD), the staging of CKD, and recognize the challenges and limitations with the current classification system.

Identify risk factors in the development and progression of CKD as well as associated complications including death.

Recognize that early recognition of progressive CKD, with appropriate management and early referral, should lead to both clinical and economic benefits.

Case 56 y/o white female with hx of DM presents as a new patient to your

office

Vitals: BP: 165/102 HR: 80

PE/ROS otherwise unremarkable

UA reveals proteinuria

Creatinine of 1.2 mg/dL

Does this patient have CKD ? ?

How severely compromised is her renal function?

Is creatinine an acceptable marker

Etiology: DM vs. HTN

Objectives

Identify patients with chronic kidney disease (CKD), the staging of CKD, and recognize the challenges and limitations with the current classification system.

Identify risk factors in the development and progression of CKD as well as associated complications including death.

Recognize that early recognition of progressive CKD, with appropriate management and early referral, should lead to both clinical and economic benefits.

Vol 1, CKD, Ch i

Data Source: Medicare 5 percent sample. This graphic also appears as Figure 2.1.

Figure i.4 Temporal trends in CKD prevalence, overall and by CKD stage, among Medicare patients age 65+, 2000-2012

http://www.usrds.org/2014

Definition Of CKD

There are two independent criteria for CKD:

Kidney damage for ≥ 3 months structural or functional abnormalities of the kidney, with or without

decreased GFR, manifest by either:

pathological abnormalities; or

markers of kidney damage, including abnormalities in the composition of the blood or urine; or abnormalities in imaging tests.

GFR < 60 mL/min/1.73m2 for ≥ 3 months, with or without kidney damage.

Pathologic Abnormalities

By Radiology (US, CT, MR, etc.) Multiple cysts consistent with polycystic kidney disease

(PKD)

Extensive scarring

Small kidneys--but be careful of the term “medical renal disease”

Renal masses or cysts that are not simple should be referred to a urologist

By Histology--i.e., renal biopsy

Markers of “Kidney Damage”

Electrolyte and other abnormalities due to tubular disorders

Urine sediment abnormalities Proteinuria

Microalbuminuria

Hematuria (especially when seen with proteinuria) Isolated hematuria has a long differential: infection, stone, malignancy,

etc.

Casts (especially with cellular elements)

History of kidney transplantation

YES NO

Risk Factor Reduction • Determine Stage of CKD

• Determine underlying cause

• Identify risk factors for

progression

• Identify comorbidities

Patient meets definition of Chronic Kidney Disease?

Creatinine Vs GFR Why Estimate GFR From SCr ?

Serum Creatinine Alone Is a Poor Indicator

of Kidney Function

Why Estimate GFR From SCr, Instead

of Using SCr for Kidney Function?

Age Gender Race SCr (mg/dL) eGFR (mL/min/1.73 m2)

CKD stage

20 M B 1.3 91 1*

20 M W 1.3 75 2*

55 M W 1.3 61 2*

55 F B 1.3 55 3

55 F W 1.3 46 3

GFR calculator available at: www.kidney.org/index.cfm?index=professionals.

B = black; †W = all ethnic groups other than black.

* If pathological abnormalities or markers of kidney damage

Glomerular Filtration Rate (GFR)

GFR is the best overall index of kidney function in health and disease. Normal GFR varies according to age, sex, and

body size.

Young adults ≈ 120-130 mL/min/1.73 m 2 and declines with age.

GFR can be estimated from prediction equations (eGFR) MDRD Study (recommended by K/DOQI)

Cockcroft-Gault formula

Stage Description GFR Action

At increased risk ≥ 90 (with CKD

risk factors)

Screening, CKD risk reduction

1 Kidney damage with

normal or ↓ GFR

≥ 90 Diagnosis and treatment, Treatment of co-

morbid conditions, Slowing progression,

CVD risk reduction

2 Kidney damage with

mild ↓ GFR

60-89 Estimating progression

3 Moderate ↓ GFR 30-59 Evaluating and treating complications

4 Severe ↓ GFR

15-29 Preparation for kidney replacement

therapy

5 Kidney Failure <15 (or dialysis) Replacement (if uremic)

Stages of Chronic Kidney Disease (CKD)

Adapted from NKF K/DOQI

Vol 1, CKD, Ch i

Data Source: National Health and Nutrition Examination Survey (NHANES), 1988–1994, 1999-2004 & 2007–2012 participants age 20 & older. Abbreviations: CKD, chronic kidney disease. This graphic also appears as Figure 1.11.

Figure i.3 NHANES participants with CKD aware of their kidney disease, 1999-2010

http://www.usrds.org/2014

MDRD

eGFR (mL/min/1.73 m 2) = 186 x (Creat/88.4)-1.154 x (Age)– 0.203 x (0.742 if female) x (1.210 if AA)

Limitations The MDRD Study equation is less accurate at GFR estimates greater

than 60 mL/min/1.73 m2

At levels of estimated GFR less than 60 mL/min/1.73 m2, the equation is accurate for most persons of average body size and muscle mass

The MDRD Study equation has not been validated in children (age < 18 years)

pregnant women

elderly (age > 70 years)

racial or ethnic subgroups other than Caucasians and African Americans

individuals with normal kidney function who are at increased risk for CKD

Lab Results From 1995

Fast Forward to 2010

45 y/o female with cirrhosis

24 hour urine collection: 45 y/o with cirrhosis

By MDRD eGFR 53 mL/min/1.73 m2 based on serum creatinine of 1.11 mg/dL

Definition of Proteinuria

Nephrotic Range ≥ 3.5 g/day

Overt Proteinuria > 300 mg/day

Microalbuminuria 30-300 mg/day

Orthostatic Proteinuria

Objectives

Identify patients with chronic kidney disease (CKD), the staging of CKD, and recognize the challenges and limitations with the current classification system.

Identify risk factors in the development and progression of CKD as well as associated complications including death.

Recognize that early recognition of progressive CKD, with appropriate management and early referral, should lead to both clinical and economic benefits.

Causes of Kidney Failure

37%

19%4%

16%

24%

Diabetes

Hypertension

Glomerulonephritis

Polycystic Kidney

Disease

Other

Diabetes is the Predominant Cause of Kidney Failure

US Renal Data System 2005 Annual Data Report

Patient Characteristics Associated with Increased

Rate of GFR Decline

Nonmodifiable

African American race

Female gender

Old age

Lower baseline level of

kidney function

Modifiable

Higher level of

proteinuria

Higher BP

Poor glycemic control

Smoking

2nd study out of Kaiser Permanente

Analyzed outcomes in

1,120,295 adults with CKD.

Median follow up 2.84 yrs.

Cardiovascular events

followed stepwise

progression

0

5

10

15

20

25

30

35

40

>60 45-59

30--44

15-29

<15

Death from anycause

Cardiovasculardisease

•Most patients died of cardiovascular

causes

2004,351:1296-1305

Majority of CKD patients died before

ending up on dialysis.

Vol 1, CKD, Ch i

Data source: Medicare 5 percent sample. January 1 point prevalent Medicare patients age 66 and older. Adj: age/sex/race/prior year hospitalization/comorbidities. Ref: 2012 patients. Abbreviations: CKD, chronic kidney disease. This graphic also appears as Figure 3.1.

Figure i.7 Unadjusted and adjusted all-cause mortality rates (per 1,000 patient years at risk) for Medicare patients aged 66 and older, by CKD status and year, 1995-2012

(A) Unadjusted (B) Adjusted

http://www.usrds.org/2014

Objectives

Identify patients with chronic kidney disease (CKD), the staging of CKD, and recognize the challenges and limitations with the current classification system.

Identify risk factors in the development and progression of CKD as well as associated complications including death.

Recognize that early recognition of progressive CKD, with appropriate management and early referral, should lead to both clinical and economic benefits.

CKD

death

Stages in Progression of Chronic Kidney Disease

and Therapeutic Strategies

Complications

Screening

for CKD

risk factors

CKD risk

reduction;

Screening for

CKD

Diagnosis

& treatment;

Treat

comorbid

conditions;

Slow

progression

Estimate

progression;

Treat

complications;

Prepare for

replacement

Replacement

by dialysis

& transplant

Normal Increased

risk

Kidney

failure Damage GFR

AJKD 2002: 39(2)

Stage 1-2 Stage 3 Stage 4 Stage 5

GFR >60 30-59 15-29 <15

BP control, ACEI/ARB

Glycemic control

CVD risk reduction: Dyslipidemia

management, Tobacco cessation

Avoid NSAIDS/Contrast

Anemia

Nutrition

Renal bone disease

Vascular access & Transplantation

CKD Intervention: Clinical Action Plan

Preparation for Renal Replacement

Therapy

Pre-emptive transplantation

ESRD options/education

ESRD outcomes

Hemodialysis

Peritoneal Dialysis

Case 56 y/o white female with hx of DM presents as a new patient to your

office

Vitals: BP: 165/102 HR: 80

PE/ROS otherwise unremarkable

UA reveals proteinuria

Creatinine of 1.2 mg/dL

Does this patient have CKD ? ?

How severely compromised is her renal function?

Is creatinine an acceptable marker

Etiology: DM vs. HTN

Case : Suggestive findings

56 yr old W female hx DM, uncontrolled HTN with a cr 1.2 mg/dL and dipstick positive for 1 + proteinuria

Suggestive of Diabetic Nephropathy: evidence of micro-

vascular complications like retinopathy, neuropathy, large kidneys, macroalbuminuria or microalbuminuria plus retinopathy or > 10 yr of type 1 diabetes with microalbuminuria

Suggestive of Hypertensive Nephrosclerosis: long history of hypertension with retinopathy, left ventricular hypertrophy, small kidneys, slowly progressive renal insufficiency, gradually increasing non-nephrotic proteinuria

* Referring clinicians may wish to discuss with their nephrology service depending on local arrangements regarding monitoring or referring.

Source: KDIGO 2012 Clinical Practice Guideline for the Evaluation and Management of CKD. Volume 3, Issue 1, January 2013.

Reproduced with permission of Kidney Disease Improving Global Outcomes (KDIGO) / www.kdigo.org

COMPLIMENTS OF:

Referral Decision Making By GFR and Albuminuria

Early vs. Late Referral: Consequences and Benefits

Consequences of late referral

Anemia and bone disease

Severe hypertension and fluid overload

Low prevalence of permanent access

Higher initial hospitalization rate

Higher 1-year mortality

Less patient choice of dialysis modality choice

Worse psychosocial adjustment

Benefits of early referral

Delay need to initiate dialysis

Higher proportion of permanent access

Greater choice of treatment options

Reduced need for urgent dialysis

Reduced hospital LOS and cost

Improved nutritional status

Better management of CVD and comorbid conditions

Higher patient survival

Kidney Wellness Center

Components of Carolina Nephrology Kidney Wellness Center

Disease Monitoring

Integration with other chronic disease management programs including DM, HTN, and CHF

Rx management and dietary advice

Anemia Management

Vaccination programs

Information and psychosocial support

Renal replacement therapy education (HD, PD, and transplant)

Advanced care planning and end-of-life care (where appropriate)

Overall expenditures on Parts A and B services for the Medicare population age 65+ and for those with CKD, by year, 1993-2012

Vol 1, CKD, Ch 6

Data source: Medicare 5 percent sample. Abbreviations: CKD, chronic kidney disease.

http://www.usrds.org/2014

Summary

Optimal Management of the Rising Creatinine

Screen “Spot” urine albumin

microalbumin to creatinine ratio

Estimate GFR from serum creatinine using the MDRD prediction equation

Delay Progression

BP control ACE-I/ARB Blood sugar control ? Protein restriction in

advanced disease

Treat Comorbidities

Anemia

Mineral and Bone Disorder

Hyperlipidemia

Cardiovascular disease

Nutrition, Acidosis

Preparation for renal replacement

Questions/Comments

Mark D. Purcell DO Nephrology/Internal Medicine

Carolina Nephrology, PA

203 Mills Avenue

Greenville, SC 29605

(864) 271-1844

mpurcell@mykidneydoc.com