Albuminuria Risk in Hispanic Populations

Abstract

For over a century, epidemiological and clinical studies have relied on self-report for race and ethnicity. Subjects have mostly been classified into oversimplified categories such as black, white, and Hispanic. In this issue of Circulation: Cardiovascular Genetics , Peralta et al report the results from an investigation of the association between albuminuria and ethnicity and race, measured by both self-report and genetic admixture analysis, which provides an estimate of each subject's unique ancestral heritage.1 Article see p 240 The authors chose to analyze albuminuria as the major phenotype because it is an important marker of chronic kidney disease (CKD) and a risk factor for progression of CKD.2,3 Furthermore, albuminuria has long been recognized as a major risk factor for cardiovascular morbidity and mortality. Mogensen discovered over 25 years ago that albuminuria is associated with increased all-cause mortality in patients with type 2 diabetes.4 Since then, it has been shown that among nondiabetic subjects with hypertension, microalbuminuria is associated with cardiovascular and cerebrovascular events5 as well as CKD risk.6 In healthier populations, albuminuria is also a risk factor for mortality7 and for mortality, myocardial infarction, and end-stage renal disease at all levels of glomerular filtration rate.8 The link between albuminuria and increased morbidity and mortality is not well understood but may reflect endothelial dysfunction among multiple vascular beds.9 The importance of microalbuminuria, typically defined as a urine albumin to creatinine ratio between 30 and 300 mg/g, is debated because microalbuminuria often reverts to normoalbuminuria, and the associated risk for morbidity and mortality is significantly less than for macroalbuminuria.5,10,–,12 For this reason, microalbuminuria is …