Lessons learned from AASK (African-American Study of Kidney Disease and Hypertension) Janice P. Lea, MD, MSc, FASN Professor of Medicine Chief Medical Director of Emory Dialysis ASH Clinical Specialist in Hypertension Emory University, Renal Division
Stage 5 CKD Incidence Rates per Million Vary by Race/Ethnicity Incidence Rate per Million (2001) 1000 750 500 250 0 254 988* 696* Caucasian Black Native American 395* Asian 325 Non- Hispanic 471* Hispanic Odds ratios: 1 3.89 2.74 1.56 1 1.45 *P<0.0001 Reference population. Data adjusted for age and gender from 2001 in United States Renal Data System. 2003 Annual Data Report. Available at: www.usrds.org.
Hypertension: The 2 nd Most Common Cause of ESRD Primary Diagnosis For Patients Who Start Dialysis Other Glomerulonephritis 700 600 Diabetes 50.1% 10% 13% Hypertension 27% No of Patients Projection 95% CI Number of Dialysis Patients 500 400 300 200 100 0 520,240 281,355 243,524 R 2 = 99.8% 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 United States Renal Data System. Annual data report. 2000.
Hypertension in African Americans Prevalence, severity, and impact of hypertension are increased in African Americans Lower achievement rate of BP control As monotherapy, β-blockers, ACE inhibitors or ARBs may produce less blood pressure lowering effects than in whites Diuretics and CCBs may have greater BP efficacy Differential responses are minimized by drug combinations that include adequate doses of diuretics National Heart, Lung, and Blood Institute. JNC 7 Express. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure. 2003.
AASK Study Questions Does very aggressive lowering of blood pressure result in slower decline in renal function? Does the type of antihypertensive agent used to initiate blood pressure lowering matter with regard to renal outcomes?
African American Study of Kidney Disease and Hypertension (AASK) Therapy: Usual Aggressive Goal MAP: 102-107 mm Hg 92 mm Hg N = 217 Amlodipine Amlodipine N = 436 Ramipril Ramipril N = 441 Metoprolol Metoprolol 1094 patients with HTN and CKD, 4 yr f/u GFR = 20-65 ml/min/1.73 m 2, Subsequent 10 yr f/u Excluded DBP <95 mm Hg, DM, UP/Cr >2.5 MAP = mean arterial pressure; DBP = diastolic blood pressure; UP/Cr = urinary protein to creatinine ratio. Wright et al for the AASK Study Group. JAMA. 2002;288:2421-2431.
Mean Arterial Pressure During Follow-up 130 MAP (mm Hg) 120 110 100 Lower BP Goal (Achieved: 128/78) Usual BP Goal (Achieved: 141/85) 90 80 0 4 12 20 28 36 44 52 60 Follow-up Month
Composite Clinical Outcome Declining GFR Event, ESRD or Death % with Events 40 35 30 25 20 15 10 5 0 Lower BP (Achieved: 128/78) Usual BP (Achieved: 141/85) Low vs. Usual: RR=2%, (p=0.85) 0 6 12 18 24 30 36 42 48 54 60 Follow-Up Time (Months) RR=Risk Reduction, adjusted for baseline covariates
Clinical Evidence for Risk Reduction With ACE Inhibitor or β Blockade: AASK Composite Risk (%) 0-10 -20-30 -40-38 Ramipril vs Amlodipine P = 0.004 Ramipril vs Metoprolol P = 0.04 Metoprolol vs Amlodipine P = 0.17-50 Composite risk of rapid GFR decline-decrease from baseline of 50% or 25 ml/min/1.73 m 2, kidney failure, or death -22-20 Patients with existing kidney damage (baseline UP/Cr >0.22). Wright et al for the AASK Study Group. JAMA. 2002;288:2421-2431.
Percent Change in Proteinuria from Baseline % Change (SE) 172 122 82 49 22 0-18 -33 Amlodipine Ramipril Metoprolol 0 6 12 18 24 30 36 42 48 Follow-up Month Geometric mean urine protein/creatinine ratio declined faster in ramipril and metoprolol groups than amlodipine group (p < 0.001)
% of Patients Reached Urine Protein/Creatinine Ratio>0.22 During Follow-up by Drug Group 60 50 Amlodipine Ramipril Metoprolol Ramipril vs. Metoprolol: p=0.014 Amlodipine vs. Metoprolol: p=0.009 Ramipril vs. Amlodipine: p<0.001 % w i t h E v e n t s 40 30 20 10 0 0 6 12 18 24 30 36 42 48 54 60 Follow-up Month Analysis of patients with UP/Cr < 0.22 at baseline
Albuminuria is mediated by efferent arteriolar constriction -Angiotensin II (Ang II) Ang II Hypertension Afferent arteriolar dilation Efferent arteriolar constriction Glomerular hypertension Albiminuria
% w i t h E v e n t s 70 60 50 40 30 20 10 0 Association of Main Clinical Composite Outcome (GFR Event, ESRD, or Death) With Baseline Proteinuria P < 0.001 Baseline UP/Cr < 0.22 Baseline UP/Cr > 0.22 0 6 12 18 24 30 36 42 48 54 60 Follow-up Month
Percent Change in Proteinuria from Baseline % Change (SE) 172 122 82 49 22 0-18 Lower BP Goal Usual BP Goal P < 0.001 0 6 12 24 36 48 Follow-up Month % change in geometric mean urine protein/creatinine ratio
Conclusion: AASK Blood Pressure Control Study Pharmacological lowering of blood pressure to levels known to protect against cardiovascular events are achievable in patients with hypertensive nephrosclerosis Aggressive lowering of BP did not result in a significantly slower rate of decline in GFR (primary endpoint) did not result in significant difference in composite endpoint of rapid decline in GFR or ESRD or death (secondary endpoint) did result in significant reduction in proteinuria
Lea et al, Arch. Int. Med. 2005 l
Six Month Change in Proteinuria from Baseline Predicts Outcome of Kidney Disease: Results from the AASK trial 4.0 Relative Risk of ESRD 2.0 1.0 0.5 0.25 0.125 >-50% >-50% to 20% -20% to +25% +25% to 100% >+100% Lea J et.al. Arch Intern Med. 2005;165:947
Magnitude of Proteinuria Reduction Predicts Risk of ESRD (AASK) Lea et al, Arch. Int. Med. 2005 The baseline level and change at 6 months in proteinuria were strong predictors of subsequent progression of hypertensive kidney disease. The relationship extended to participants with normo- to microalbuminuria.
Intensive Blood-Pressure Control in Hypertensive Chronic Kidney Disease Lawrence J. Appel, M.D., M.P.H., Jackson T. Wright, Jr., M.D., Ph.D., Tom Greene, Ph.D., Lawrence Y. Agodoa, M.D., Brad C. Astor, M.P.H., Ph.D., George L. Bakris, M.D., William H. Cleveland, M.D., Jeanne Charleston, R.N., Gabriel Contreras, M.D., M.P.H., Marquetta L. Faulkner, M.D., Francis B. Gabbai, M.D., Jennifer J. Gassman, Ph.D., Lee A. Hebert, M.D., Kenneth A. Jamerson, M.D., Joel D. Kopple, M.D., M.P.H., John W. Kusek, Ph.D., James P. Lash, M.D., Janice P. Lea, M.D., Julia B. Lewis, M.D., Michael S. Lipkowitz, M.D., Shaul G. Massry, M.D., Edgar R. Miller, Ph.D., M.D., Keith Norris, M.D., Robert A. Phillips, M.D., Ph.D., Velvie A. Pogue, M.D., Otelio S. Randall, M.D., Stephen G. Rostand, M.D., Miroslaw J. Smogorzewski, M.D., Robert D. Toto, M.D., and Xuelei Wang, M.S. for the AASK Collaborative Research Group N Engl J Med 2010; 363:918-929September 2, 2010
Prevalence and Correlates of LVH in AASK ( Peterson et al, HTN 2007) LVH present in 66.7% of men and 73.9% of women; this contrasts with most series ~ 30%. 24 hr ABPM- SBP, lower GFR, younger age in MV analyses predicted LVH.
Alves et al, JASN
Metabolic Syndrome in CKD (Cardiorenal) The tendency for cardiovascular disease risk factors to occur in clusters has lead to the description of metabolic syndrome. The impact of the different components of the syndrome on the relative risk of CV death in the general population is not clearly established. CKD has recently emerged as a CV mortality risk factor
National Cholesterol Education Program Clinical Identification of the Metabolic Syndrome RISK FACTOR Abdominal obesity Men Women Triglycerides HDL-C Men HDL-C Women DEFINING MEASURES Waist circumference: >40 in (>102 cm) >35 in (>88 cm) ³150 mg/dl <40 mg/dl 3 Risk factors comprise the metabolic syndrome. ICD-9 Code 277.7 Blood pressure <50 mg/dl Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. JAMA. 2001. 285:2486-2497.
Metabolic Syndrome, Proteinuria, and Progressive CKD in AASK ( Lea et al, AMJKD 2008) TABLE 3: Hazard ratio of metabolic syndrome with Time to Event analyses with and without adjustments for significant covariates and BMI and adjusted for BP goal group and Antihypertensive Drug group. Hazard Ratio Confidence Interval P value MS unadjusted 1.31 1.03-1.68.03 MS adjusted for other covariates, + uprot/cr 1.37 1.23 1.07-1.77.95-1.58.01.11 By BP goal 1.37 1.05-1.8.02 By Drug group 1.35 1.03-1.78.03
Key Points for Optimal Hypertension Management <140/90 mm Hg JNC 7 BP Goals <130/80 mm Hg in diabetes or renal disease JNC 7 recommends: If SBP >20 mm Hg, DBP >10 mm Hg over goal, consider initiating with 2-drug combination JNC 7 Report. Hypertension. 2003;42(6):1206-1252. 28
Recommendations for BP and RAS Management in CKD Patient Group Goal BP (mm Hg) First Line Adjunctive + Diabetes <130/80 ACE-I or ARB Diuretics then CCB or BB Diabetes + Proteinuria <130/80 ACE-I or ARB Diuretics then CCB or BB Diabetes Proteinuria <130/80 No specific preference: Diuretics then ACE-I, ARB, CCB, or BB EXPECT TO NEED TO USE 3+ AGENTS TO ACHIEVE GOALS Recommendations largely consistent across JNC 7, ADA, and K/DOQI BP = blood pressure; RAS = renin angiotensin system; CCB = calcium channel blocker; BB = β-blocker; JNC 7 = The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. ADA. Diabetes Care. 2005;28(suppl 1); Chobanian et al. JAMA. 2003;289:2560-2572; Kidney Disease Outcomes Quality Initiatives (K/DOQI). Am J Kidney Dis. 2004;43(5 suppl 1):S1-S290.
Average Number of Antihypertensive Agents Needed Per Patient to Achieve Diastolic BP Goals UKPDS (<85 mm Hg Diastolic) ABCD (<75 mm Hg Diastolic) MDRD (<92 mm Hg MAP) HOT (<80 mm Hg Diastolic) AASK (<92 mm Hg MAP) 1 1.5 2 2.5 3 3.5 4 No. of BP medications Bakris et al. Am J Kidney Dis. 2000;36:646.
Clinical Implications of AASK These results support the use of ACEI as initial therapy to control BP in a multidrug regime over DHP-CCB or β-blockers in CRF due to HTN. AASK documents renoprotective effects of ACEI in African-Americans, a population thought previously less responsive to ACEI. It is not known whether the addition of a CCB or β-blocker to an ACEI will blunt renoprotection. Aggressive lowering of BP to <140/90 in <1 gm proteinuria does not slow GFR decline or delay ESRD, findings c/w MDRD study.
Summary Lower BP goals mostly benefit hypertensive CKD pts with > 300 mg/g proteinuria. Degree of proteinuria predicts progression to ESRD in those with and without Metabolic syndrome. Future randomized prospective trials needed to evaluate racial disparities in CVD and mortality in CKD patients.
Reducing Risks of Kidney Disease in African-Americans Education Early detection of kidney disease Adequate treatment of hypertension and diabetes Adequate access to healthcare Proper dietary habits More clinical research in African- Americans to better understand the increased risks