Implications of ethnicity for the treatment of hypertensive kidney disease, with an emphasis on African Americans

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Abstract

The recognition of chronic kidney disease (CKD) as an important public health issue has fostered an increasing number of strategies to increase CKD awareness and to reduce both the prevalence and the complications of CKD. Despite these advances, end-stage renal disease (ESRD) and cardiovascular events remain the major complications of CKD. Although the ESRD epidemic is attributed in greater part to the increasing rate of diabetes, hypertension remains the second most common reported cause of ESRD and is present in approximately 90% of cases of diabetes-related ESRD. The disproportionately high prevalence of hypertension in ethnic minorities, as well as the difficulty of achieving adequate blood-pressure control in these populations, contributes substantially to the high rate of CKD progression and complications in these groups. Although the role of hypertension as a primary cause of CKD is debated, hypertension is commonly recognized as the most important CKD progression factor. Important differences have been reported in the degree and likelihood of blood-pressure response to antihypertensive medications between ethnic groups, but ethnicity seems to be less important as a determinant of clinical outcomes. In this Review we examine key ethnic variations in hypertensive CKD in terms of pathophysiology, response to antihypertensive therapy, clinical outcomes, and evidence-based recommendations for blood-pressure control, with an emphasis on African Americans.

Key Points

  • Guidelines suggest that renin–angiotensin inhibition should be the initial therapy for hypertension in all patients with chronic kidney disease (CKD); a diuretic and at least one other agent is usually also required to achieve the blood-pressure goal of <130/80 mmHg

  • Ethnicity is associated with many biologic and sociocultural variations that might influence blood pressure, blood-pressure control and the risk and progression of CKD

  • African Americans with hypertension have a higher risk of developing CKD and a faster rate of CKD progression than white patients with hypertension

  • Some studies have reported that African Americans have lower blood-pressure response rates than whites to some antihypertensive agents

  • No clinically relevant ethnic differences in outcomes have been noted in patients with CKD following evidence-based pharmacologic interventions for blood-pressure control; in part, this is because of the paucity of data, which reinforces the need to achieve greater ethnic diversity in clinical trials

  • In addition to considering the evidence base when treating hypertensive CKD, clinicians should pay detailed attention to potential cultural and socioeconomic influences that disproportionately affect adherence among ethnic minority patients

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Figure 1: Key sociocultural determinants of chronic kidney disease.

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Acknowledgements

Support for this article was provided in part by the National Center for Research Resources, Research Centers in Minority Institutions (RR11145 to KCN, NT and DM; and U54 RR019234 to KCN, NT, DM, and NDV), and the DREW/UCLA Project EXPORT, National Institutes of Health, National Center on Minority Health & Health Disparities (P20-MD00182 to KCN).

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Correspondence to Keith C Norris.

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Competing interests

KC Norris has acted as a consultant for Amgen and Abbott, has received grant/research support from Monarch Pharmaceuticals and has been on speakers' bureaux for Abbott, Amgen, Merck, Monarch and Pfizer.

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