Risk Factors for Progressive Chronic Kidney Disease
William M. McClellan and
W. Dana Flanders
Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia.
Correspondence to Dr. William McClellan, Georgia Medical Care Foundation, 57 Executive Park South, NE, Suite 200, Atlanta, GA. Phone: 404-982-7573; Fax: 678-527-3473
ABSTRACT. The occurrence of chronic kidney disease and subsequentrate of loss of renal function are highly variable among individualswith the same underlying cause of renal injury or degree offunctional impairment. Individual variability of risk is typicalof complex diseases and reflects the multifactorial nature ofthe biologic mechanisms that are involved in the underlyingdisease process. The utility of the risk factor concept in developingCKD prevention and control strategies includes identifying individualsat high risk for the occurrence and progression of CKD, definingat-risk populations, elucidating potential targets for intervention,and generating explanatory hypotheses for the variable riskof CKD noted in different populations. Future application ofthe risk factor concept in the prevention and control of CKDwill entail developing multivariate prediction equations; usingspatial and temporal, as well as personal, characteristics,to define at-risk populations; identifying biomarkers for complexrisk factors like race; and translating this information intotestable interventions. This should include active extensionof our current understanding of health care, social, and economicrisk factors at both the individual and the community level.E-mail: bmcclellan@gmcf.org
The incidence and progression of renal injury vary substantiallyamong individuals who are at-risk for kidney disease. For example,8% of new patients with type 2 diabetes mellitus already haveproteinuria at diagnosis (1). Among patients with type 2 diabetesmellitus who are initially free of proteinuria, the 20-yr riskof diabetic nephropathy is 41% (1). After proteinuria occurs,the subsequent 10-yr risk of progressive chronic kidney diseaseis 11% (2). Thus, about half of those with type 2 diabetes willdevelop nephropathy and 10% of these individuals will experienceprogressive loss of renal function. Variable risk of impairedrenal function has also been reported among hypertensive subjects.At study entry, 5.9% of the Hypertension Detection and Follow-upProgram trial participants had a serum creatinine of 1.5 mg/dlor greater and 2.3% of the 8683 participants with serial serumcreatinine measurements over 5 yr experienced clinically significantloss of renal function (3).
Similarly, the rate of loss of renal function among individualswith CKD also displays considerable person-to-person variability.For example, the Modification of Diet in Renal Disease (MDRD)study reported that the mean (SD) rate of decline in GFR duringfollow-up was 3.8 (± 4.2) ml/min per yr for patientswith moderate and 4.0 (± 3.1) ml/min per yr for thosewith severe renal insufficiency at baseline (4). Substantialproportions of each group, 19% and 11%, respectively, showedno progression during follow-up, further indicating variabilityin progression.
Risk Factors and Variable Risk.
Variability of risk for the occurrence and progression of CKDsuggests that biologically relevant characteristics exist thatinfluence the occurrence or course of the renal disease. Thevariable progression of CKD among individuals with autosomaldominant polycystic kidney disease (ADPKD) illustrates thisconcept. The mutation of the polycystin gene that occurs withinfamily members is a necessary risk factor for ADPKD. However,family members who inherit the same mutation demonstrate highlyvariable rates of progression to ESRD (5). The within-familyheterogeneity of time of onset of ESRD indicates that the rateof progression of CKD among individuals with the same ADPKDgene is associated with one or more independent exposures otherthan the mutation itself. Combinations of causal factors thatresult in rapid progression to ESRD define sufficient causesfor early loss of renal function among ADPKD patients (6). Althoughsome or all of the other component causes for rapid progressionof ADPKD may also be genetic, this formulation of necessaryand sufficient causes tempers inclinations to monogenic determinismand emphasizes the multifactorial nature of most, if not all,diseases.
The risk factor concept emphasizes that an exposure may be causalor may simply be associated with some other, perhaps unidentified,causal factor.1 Evidence supporting a potential causal rolefor a risk factor includes strong, graded associations withthe disease that are consistent across different populationsand study designs. A biologic link between the risk factor andthe disease, relevant animal models, and strong dose-responserelationships can also provide support of a causal role fora risk factor. However, in many instances neither the presenceof association nor the presence of strong supporting evidenceis sufficient to establish causality and, often, causal evidencemust rest on outcomes from randomized clinical trials.
Even though a risk factor need not be causal, the concept hasconsiderable utility in developing disease prevention and controlstrategies. First, risk factors can be used to identify individualsat high risk for the occurrence and progression of CKD. Second,risk factors can identify at-risk populations. Third, risk factorscan identify potential new targets for intervention. Fourth,risk factors generate explanatory hypotheses. Each of theseapplications of the risk factor model to CKD warrants furthercomment.
Prediction of increased risk of occurrence or progression ofCKD enables clinicians to identify individuals who may benefitfrom closer supervision of care or more intensive disease modifyinginterventions. Risk stratification using single patient characteristicsis a straightforward application of this concept. Extendingthis concept to multiple risk factors requires statistical modelsthat combine the contribution of multiple factors into a singlesummary score. For chronic kidney disease, interest has focusedon risk factors for its occurrence and rate of progression.Information about these risk factors can be used in risk prediction(7,8).
Associations between patient characteristics and the occurrenceof kidney disease identify risk factors for disease occurrence.For a factor that increases risk, the probability of diseasewhen the factor is present exceeds that in absence of the characteristic
(1)
Multivariate logistic regression models can account for thejoint effects of multiple factors on the occurrence of CVD (19,20).The multivariate logistic model provides an estimation of riskfor subsequent disease:
(2)
where p is the probability of CKD during a stipulated periodof observation, and i are logistic regression parameters derivedfrom data for the population of interest, risk factor i is theindividuals value for the ith characteristic and thesummation is over risk factors i = 1, 2, 3, ... n.
Although a widely accepted risk prediction model for the occurrenceof CKD has not yet been developed for CKD, a recent cohort studyillustrates a type of study design from which a prediction modelcould be derived (9). The study examined the 10-yr risk of developingESRD among 107,192 participants aged 18 yr and older at baseline.ESRD occurred in 193 patients (0.18%). Patient characteristicsconsidered as candidate risk factors for progressive CKD includedgender, age at screening, proteinuria, hematuria, and systolicand diastolic BP. An independent association (adjusted oddsratio, 95% confidence interval) was found between risk of ESRDand proteinuria (14.9, 10.9 to 20.2), hematuria (2.30, 1.62to 3.28), male gender (1.41, 1.04 to 1.92), and diastolic BP(1.39, 1.17 to 1.64).
Information about the rate of change in renal function overtime can serve as a measure of disease progression. Progressionrates, which measure change in renal function per unit of time,should be clearly distinguished from incidence rates for CKD,which are measured in incident cases per person-year. Progressionof CKD can be measured using serum creatinine (10), reciprocalof the serum creatinine (11), Cockcroft-Gault estimated GFR(or similar estimating equation) (12), creatinine clearance(13), or log-normalized albumin excretion rate (14). At presentthere is no consensus as to which of these measures is bestfor risk prediction.
Risk factors for progression can be defined in a manner similarto that for occurrence:
(3)
Multivariate linear models can extend the simple comparisonof rates in two groups to account for multiple risk factors.Finally, individual rates of progression can be predicted bythe multivariate model:
(4)
where the predicted rate is the expected decline in renal function, and i are linear regression parameters derived from the datafor the population of interest, and risk factors i the individualsvalues for the characteristics included in the model. Becauserenal function is measured serially for each patient, it isnecessary to account for the correlated nature of the outcomedata using a linear growth curve or similar models (15).
A widely accepted prediction model for the rate of progressionof CKD has not yet been developed. A report from the MDRD trialillustrates how an equation to predict progression of CKD mightbe derived (4). The MDRD investigators examined 41 potentialrisk factors for loss of renal function as measured by 125I-iothalamateGFR. Factors independently associated with the progression ofCKD included black race, increased mean arterial BP, baselineurine protein excretion, a diagnosis of polycystic kidney disease,and lower baseline levels of serum transferrin and HDL cholesterol.These six factors accounted for 34.5% of the variation in therate of progression in mild and 33.9% in moderate renal insufficiency.
The search for risk factors for CKD seeks to identify modifiableprocesses or mediators responsible for the occurrence and progressionof renal failure. Table 1 lists some known risk factors forrenal failure. Some of these factors, like the use of angiotensinconverting enzyme inhibitors, BP control and glycemic control,have been tested in randomized clinical trials (RCT) that haveestablished them as disease-modifying interventions and suitabletargets for intervention. Others, like analgesic abuse and smoking,are supported by strong observational evidence. Although RCTevidence is lacking that cessation of smoking or of chronicanalgesic use is renoprotective, it is reasonable to suggestthat interventions targeted at these risk factors, particularlyin high-risk populations, can be supported. Other factors, likeanemia, are currently the subjects of large, well designed RCT;recommendations for specific intervention await supportive evidencefrom the completion of these trials.
Table 1. Factors associated with the occurrence or progression of CKD
In contrast, many of the risk factors listed in Table 1 likerace, family membership, and socioeconomic status are complexmeasures and the biologic mechanisms that link them to the occurrenceand progression of CKD are not defined. One challenge posedby these poorly characterized risk factors is to find associatedbiomarkers that directly link them to disease processes. Biomarkersare measured at the tissue, cellular, subcellular, molecular,or genetic level (43). They can potentially reduce misclassificationand measurement variation. Furthermore, biomarkers may be moreindicative of relevant disease processes that can suggest therapeuticinterventions, which can be tested in RCT. Examples of biomarkersassociated with increased risk of CKD are listed in Table 1.
Risk factors can be used to define at-risk population that canbe targeted for education and early intervention programs. Groupsdefined by race are often mentioned as at-risk populations.Blacks, for example, have a considerably higher risk of ESRDpartially due to hypertension and diabetes. This increased riskpeaks during early adulthood and cannot be fully accounted forby racial differences in the underlying prevalence of hypertension(44). A recent study by Kiberd and Clase estimated the cumulativerisk of ESRD among different gender-race groups (45). They foundthat the lifetime of ESRD for a 20-yr-old black woman was 7.8%;for black males, 7.3%; for white women, 1.8%; and for whitemales, 2.5%. The number of years of life lost due to ESRD wascomparable to the loss due to breast cancer among black womenand prostate cancer among black men.
Space and time can also define at-risk populations. For example,maps of race- and cause-specific ESRD incidence published bythe United States Renal Data System reveal a substantial nonrandomdistribution of high risk populations for diabetes and hypertension(46). Those geographic areas where higher ESRD rates are foundmight be considered for targeted interventions. These geographicvariations in risk also suggest that there may be environmentaland social determinants of CKD risk, which are not accountedfor within the traditional risk factor model.
A recent study by Lopes and Port of the age-specific patternsof black to white risk of nondiabetic ESRD illustrates the useof time as a risk factor to identify high-risk groups (47).They found that the relative risk of blacks compared to whitesfor CKD demonstrated considerable variability with age, peakingin middle adulthood and then declining, suggesting that blacksin midlife experience greater absolute and relative risk ofCKD than at other times during their life span.
Risk factors generate explanatory hypotheses that can lead topotential interventions. One set of explanatory hypotheses seeksto reduce complex exposures to potential causal factors. Welldefined CKD risk factors that display a strong, graded associationwith the occurrence of CKD, which is consistent across studiesin different populations and is related to biologic mechanismsresponsible for renal injury and progressive loss of function,identify potential targets for disease modifying interventions.However, as noted above, many CKD risk factors are complex andnot well defined. In such cases, it is necessary to considerhow they might be linked to potential interventions.
A second explanatory issue revolves around the amount of therisk within a population that can be accounted for by a setof risk factors, a measure called population attributable risk(48). Questions of this nature seek to quantify the proportionof risk that can be prevented by eliminating a set of knowncausal risk factors. Understanding the amount of disease withina population attributable to one or more risk factors can facilitatea more appropriate allocation of resources for prevention programs.
An approach to dealing with a complex exposure is to identify,separately measure, and study the components of the exposure.Even complex risk factors like race can be related directlyor indirectly to genetic and molecular events responsible forthe pathogenesis and progression of kidney disease. For example,the increased risk of ESRD associated with race has generatedmultiple explanatory hypotheses. Examples include studies ofmisclassification of hypertensive renal disease (49,50), racialdifferences in birth weight (51), familial aggregation of risk(25), variations in mitochondrial genes (52), poverty (22),and differential access to health care (22). Many of these riskfactors are in themselves complex and subject to reduction componentfactors. The goal of reduction toward simpler component factorsis to identify molecular biomarkers or environmental factorsthat account for the observed risk and that can be linked tobiologically relevant disease mechanisms (43).
Characteristics measured at the group level that are associatedwith increased risk are called contextual factors. The geographicvariation in risk of ESRD described above is an example of acontextual risk factor. As one of many hypotheses, it has beensuggested that economically and environmentally disadvantagedneighborhoods may account for geographic variations in risk(53,54). For example, Whittle et al. examined the associationbetween ESRD incidence rates due to hypertension and neighborhoodlevel measures of socioeconomic status derived from a randomhousehold survey (55). They found an ecological associationthatis, one occurring at the group levelwherein communitieswith lower educational and income levels tended to have higherESRD incidence rates. The inference of an association basedon ecological observations is subject to ecologic bias if theexposure (low SES) and the CKD occur in different segments ofthe population (56).
In a case-control study, the same group reported increased riskof ESRD associated with individual measures of socioeconomicstatus (household annual income and years of education) andwith measures of health care access (health insurance status,dental health, usual source of health care, and use of preventivehealth care) (22). However, this study used individual levelinformation and failed to capture the ecological informationabout risk that was observed in the population-based study.One way of dealing with this limitation is to include measuresof SES and access to health care at both the individual andgroup level in a multilevel model. The statistical models shouldaccount for the complex correlated data structure that ariseswhen individuals within communities are studied (57). A recentarticle by Diez Roux et al. examining neighborhood environments,individual socioeconomic status, and risk of coronary heartdisease illustrates this approach to contextual, multilevelmodels of risk (58).
A recent report by Tarver-Carr et al. illustrates how multivariaterisk models can be used to estimate the fraction of excess riskfor CKD among African-Americans that can be attributed to riskfactors other than race (59). They used data from the secondNational Health and Nutrition Examination survey (NHANES II)follow-up study to examine risk factors associated with higherrisk of ESRD among African Americans compared with whites. Theyadjusted black to white relative risk estimates for: (1) ageand gender alone; (2) sociodemographic factors; (3) lifestylefactors; and (4) clinical factors. They found that the proportionof the black versus white excess risk attributable to sociodemographic(poverty status, educational level, and marital status) factorswas 12%; for lifestyle factors, 24%; and for clinical factors,32%. All studied risk factors accounted for 44% of the excessrisk for CKD experienced by African Americans. These resultssuggest that the factors included in the sociodemographic, lifestyleand clinical risk sets represent important intervention targets,and that substantial variation in black to white risk of ESRDremains to be explained.
Increasing our understanding of risk factors for the occurrenceand progression of CKD poses substantial challenges. Predictivemodels for risk and rates of progression based on this informationshould be derived and validated and their clinical applicationsstudied. Biomarkers should be sought to clarify the associationsbetween complex risk factors and risk of CKD. Once a risk factorhas been fully characterized, therapeutic interventions basedon this understanding should be devised and tested with randomizedclinical trials. We should actively extend our understandingof health care and social and economic factors at the individuallevel and at the contextual level.
Footnotes
1The definition of risk factor is inconsistent within the epidemiologicliterature and some authors reserve the term for causal factors((8). Further, risk prediction equations like those from theFramingham Heart Study for cardiovascular disease risk, typicallyuse both well defined causal factors like serum cholesterollevels and poorly specified risk factors like gender.
Larson TS, Santanello N, Shahinfar S, OBrien PC, Palumbo PJ, Melton LJ 3rd, Leibson CL: Trends in persistent proteinuria in adult-onset diabetes: A population-based study. Diabetes Care 23: 5156, 2000[Abstract]
Humphrey LL, Ballard DJ, Frohnert PP, Chu CP, OFallon WM, Palumbo PJ: Chronic renal failure in non-insulin-dependent diabetes mellitus. A population-based study in Rochester, Minnesota. Ann Intern Med 111: 788796, 1989
Shulman NB, Ford CE, Hall WD, Blaufox MD, Simon D, Langford HG, Schneider KA: Prognostic value of serum creatinine and effect of treatment of hypertension on renal function. Results from the hypertension detection and follow-up program. The Hypertension Detection and Follow-up Program Cooperative Group. Hypertension 13 (Suppl I): 8093, 1989
Hunsicker LG, Adler S, Caggiula A, England BK, Greene T, Kusek JW, Rogers NL, Teschan PE: Predictors of the progression of renal disease in the Modification of Diet in Renal Disease Study. Kidney Int 51: 19081919, 1997[Medline]
Gabow PA, Johnson AM, Kaehny WD, Kimberling WJ, Lezotte DC, Duley IT, Jones RH: Factors affecting the progression of renal disease in autosomal-dominant polycystic kidney disease. Kidney Int 41: 13111319, 1992[Medline]
Rothman KJ: Causes. Am J Epidemiol 104: 587592, 1976[Free Full Text]
Kleinbaum DG, Kupper LL, Morgenstern H: Epidemiologic Research: Principles and Quantitative Methods, Belmont, CA, Lifetime Learning Publications, 1982
Kannel WB, Larson M: Long-term epidemiologic prediction of coronary disease: The Framingham experience. Cardiology 82: 137152, 1993[Medline]
Iseki K, Iseki C, Ikemiya Y, Fukiyama K: Risk of developing end-stage renal disease in a cohort of mass screening. Kidney Int 49: 800805, 1996[Medline]
Perneger TV, Nieto FJ, Whelton PK, Klag MJ, Comstock GW, Szklo M: A prospective study of blood pressure and serum creatinine. Results from the "Clue" Study and the ARIC Study. JAMA 269: 488493, 1993[Abstract]
Gabow PA, Johnson AM, Kaehny WD, Kimberling WJ, Lezotte DC, Duley IT, Jones RH: Factors affecting the progression of renal disease in autosomal-dominant polycystic kidney disease. Kidney Int 41: 13111319, 1992
Mazouz H, Kacso I, Ghazali A, El Esper N, Moriniere P, Makdassi R, Hardy P, Westeel PF, Achard JM, Pruna A, Fournier A: Risk factors of renal failure progression two years prior to dialysis. Clin Nephrol 51: 355366, 1999[Medline]
Jungers P, Hannedouche T, Itakura Y, Albouze G, Descamps-Latscha B, Man NK: Progression rate to end-stage renal failure in non-diabetic kidney diseases: A multivariate analysis of determinant factors. Nephrol Dial Transplant 10: 13531360, 1995[Abstract/Free Full Text]
Goetz FC, Jacobs DR Jr, Chavers B, Roel J, Yelle M, Sprafka JM: Risk factors for kidney damage in the adult population of Wadena, Minnesota: A prospective study. Am J Epidemiol 145: 91102, 1997[Abstract/Free Full Text]
Liang KY, Zeger SL: Longitudinal data analysis a generalized linear models. Biometrika 73: 1322, 1986[Abstract/Free Full Text]
Rodriguez-Puyol D: The aging kidney. Kidney Int 54: 22472265, 1998[Medline]
Rostand SG: US minority groups and end-stage renal disease: A disproportionate share. Am J Kidney Dis 19: 411413, 1992[Medline]
Pugh JA, Stern MP, Haffner SM, Eifler CW, Zapata M: Excess incidence of treatment of end-stage renal disease in Mexican Americans. Am J Epidemiol 127: 135144, 1988[Abstract/Free Full Text]
Hoy WE, Megill DM: End-stage renal disease in southwestern Native Americans, with special focus on the Zuni and Navajo Indians. Transplant Proc 21: 39063908, 1989[Medline]
Neugarten J, Acharya A, Silbiger SR: Effect of gender on the progression of nondiabetic renal disease: A meta-analysis. J Am Soc Nephrol 11: 319329, 2000[Abstract/Free Full Text]
Lackland DT, Bendall HE, Osmond C, Egan BM, Barker DJ: Low birth weights contribute to high rates of early-onset chronic renal failure in the Southeastern United States. Arch Intern Med 160: 14721476, 2000[Abstract/Free Full Text]
Perneger TV, Whelton PK, Klag MJ: Race and end-stage renal disease. Socioeconomic status and access to health care as mediating factors. Arch Intern Med 155: 12011208, 1995[Abstract]
Orth SR, Ritz E, Schrier RW: The renal risks of smoking. Kidney Int 51: 16691677, 1997[Medline]
Perneger TV, Whelton PK, Puddey IB, Klag MJ: Risk of end-stage renal disease associated with alcohol consumption. Am J Epidemiol 150: 12751281, 1999[Abstract/Free Full Text]
Freedman BI, Soucie JM, McClellan WM: Family history of end-stage renal disease among incident dialysis patients. J Am Soc Nephrol 8: 19421945, 1997[Abstract]
Lin JL, Tan DT, Hsu KH, Yu CC: Environmental lead exposure and progressive renal insufficiency. Arch Intern Med 161: 264271, 2001[Abstract/Free Full Text]
McLaughlin JK, Lipworth L, Chow WH, Blot WJ: Analgesic use and chronic renal failure: A critical review of the epidemiologic literature. Kidney Int 54: 679686, 1998[CrossRef][Medline]
Norris KC, Thornhill-Joynes M, Robinson C, Strickland T, Alperson BL, Witana SC, Ward HJ: Cocaine use, hypertension, and end-stage renal disease. Am J Kidney Dis 38: 523528, 2001.[Medline]
Velasquez MT, Bhathena SJ: Dietary phytoestrogens: A possible role in renal disease protection. Am J Kidney Dis 37: 105668, 2001[Medline]
Rossert JA, McClellan WM, Roger SD, Verbeelen DL, Horl WH: Contribution of anemia to progression of renal disease: A debate. Nephrol Dial Transplant 17 [Suppl 1]: 6066, 2002[Abstract/Free Full Text]
Haugen E, Nath KA: The involvement of oxidative stress in the progression of renal injury. Blood Purif 17: 5865, 1999[CrossRef][Medline]
Manitius J, Biedunkiewicz B, Kustosz J, Rutkowski B: The relationship between insulin, glucose and serum uric acid and their contribution to the progression of renal damage in patients with primary glomerulonephritis. J Int Med Res 24: 449453, 1996[Medline]
Fried LF, Orchard TJ, Kasiske BL: Effect of lipid reduction on the progression of renal disease: A meta-analysis. Kidney Int 59: 260269, 2001[CrossRef][Medline]
Jafar TH, Stark PC, Schmid CH, Landa M, Maschio G, Marcantoni C, de Jong PE, de Zeeuw D, Shahinfar S, Ruggenenti P, Remuzzi G, Levey AS: Proteinuria as a modifiable risk factor for the progression of non-diabetic renal disease. Kidney Int 60: 11311140, 2001[CrossRef][Medline]
Luke RG: Hypertensive nephrosclerosis: pathogenesis and prevalence. Essential hypertension is an important cause of end-stage renal disease. Nephrol Dial Transplant 14: 22712278, 1999[Free Full Text]
Zucchelli P, Zuccala A: The kidney as a victim of essential hypertension. J Nephrol 10: 203206, 1997[Medline]
Anonymous: Retinopathy and nephropathy in patients with type 1 diabetes four years after a trial of intensive therapy. The Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Research Group. N Engl J Med 342: 381389, 2000[Abstract/Free Full Text]
Stratton IM, Adler AI, Neil HA, Matthews DR, Manley SE, Cull CA, Hadden D, Turner RC, Holman RR: Association of glycaemia with macrovascular and microvascular complications of type 2 diabetes (UKPDS 35): Prospective observational study. Br Med J 321: 405412, 2000[Abstract/Free Full Text]
UK Prospective Diabetes Study (UKPDS) Group: Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33). Lancet 352: 837853, 1998[CrossRef][Medline]
Kasiske BL, Kalil RS, Ma JZ, Liao M, Keane WF: Effect of antihypertensive therapy on the kidney in patients with diabetes: a meta-regression analysis. Ann Intern Med 118: 129138, 1993[Abstract/Free Full Text]
Young EW, Mauger EA, Jiang KH, Port FK, Wolfe RA: Socioeconomic status and end-stage renal disease in the United States. Kidney Int 45: 907911, 1994[Medline]
Byrne C, Nedelman J, Luke RG: Race, socioeconomic status, and the development of end-stage renal disease. Am J Kidney Dis 23: 1622, 1994[Medline]
Schulte PA: A conceptual and historical framework for molecular epidemiology. In: Molecular Epidemiology: Principles and Practice,edited by Schulte PA and Perera FP, New York, Academic Press, 1993
McClellan W, Tuttle E, Issa A: Racial differences in the incidence of hypertensive end-stage renal disease (ESRD) are not entirely explained by differences in the prevalence of hypertension. Am J Kidney Dis 12: 285290, 1988[Medline]
Kiberd BA, Clase CM: Cumulative risk for developing end-stage renal disease in the US population. J Am Soc Nephrol 13: 16351644, 2002[Abstract/Free Full Text]
United States Renal Data System: 2001 Annual Data Report: Atlas of end-stage renal disease in the United States, Bethesda, MD, National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, 2001
Lopes AA, Hornbuckle K, James SA, Port FK: The joint effects of race and age on the risk of end-stage renal disease attributed to hypertension. Am J Kidney Dis 24: 554560, 1994[Medline]
Rothman KJ: Modern Epidemiology, Boston, Little, Brown and Company, 1986
Perneger TV, Whelton PK, Klag MJ, Rossiter KA: Diagnosis of hypertensive end-stage renal disease: Effect of patients race. Am J Epidemiol 141: 1015, 1995[Abstract/Free Full Text]
Blythe WB, Maddux FW: Hypertension as a causative diagnosis of patients entering end-stage renal disease programs in the United States from 1980 to 1986. Am J Kidney Dis 18: 3337, 1991[Medline]
Lopes AA, Port FK: The low birth weight hypothesis as a plausible explanation for the black/white differences in hypertension, non-insulin-dependent diabetes, and end-stage renal disease. Am J Kidney Dis 25: 350356, 1995[Medline]
Watson B Jr, Khan MA, Desmond RA, Bergman S: Mitochondrial DNA mutations in black Americans with hypertension-associated end-stage renal disease. Am J Kidney Dis 38: 529536, 2001[Medline]
Diez-Roux AV: Bringing context back into epidemiology: Variables and fallacies in multilevel analysis. Am J Public Health 88: 216222, 1998[Abstract/Free Full Text]
Yen IH, Syme SL: The social environment and health: A discussion of the epidemiologic literature. Annu Rev Public Health 20: 287308, 1999[CrossRef][Medline]
Whittle JC, Whelton PK, Seidler AJ, Klag MJ: Does racial variation in risk factors explain black-white differences in the incidence of hypertensive end-stage renal disease? Arch Intern Med 151: 13591364, 1991[Abstract]
Greenland S, Morgenstern H: Ecological bias, confounding, and effect modification. Int J Epidemiol 18: 269274, 1989[Abstract/Free Full Text]
Diez Roux AV: Investigating neighborhood and area effects on health. Am J Public Health 91: 17831789, 2001[Abstract/Free Full Text]
Diez Roux AV, Merkin SS, Arnett D, Chambless L, Massing M, Nieto FJ, Sorlie P, Szklo M, Tyroler HA, Watson RL: Neighborhood of residence and incidence of coronary heart disease. N Engl J Med 345: 99106, 2001[Abstract/Free Full Text]
Tarver-Carr ME, Powe NR, Eberhardt MS, LaVeist TA, Kington RS, Coresh J, Brancati FL: Excess risk of chronic kidney disease in African-Americans versus whites in the United States: A population-based study of potential explanatory factors. JASN, in press
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