Microalbuminuria in White and Black Hypertensive Nondiabetic Brazilian Patients

Andreza Alves Belo, Eduardo Luis Guimarães Machado, Amintas Fabiano de Souza Figueiredo, Estêvão Lanna Figueiredo

Centro de Desenvolvimento Inovação, Ciência e Tecnologia—CDICT, BHTEC, Belo Horizonte, MG, Brazil.
Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Faculdade de Ciências Médicas de Minas Gerais, Belo Horizonte, MG, Brazil.
Hospital Lifecenter, Belo Horizonte, MG, Brazil.

DOI: 10.4236/wjcd.2014.45031                

Abstract

Microalbuminuria (MAU) is a predictor of cardiovascular mortality in patients with diabetes mellitus (DM) and hypertension (HTN) and also in an unselected population. The American Diabetes Association (ADA) and the National Kidney Foundation (NKF) define MAU as an albumin/creatinine ratio (ACR) between 30 and 300 μg/mg in both men and women. Aim: To evaluate the possible relationship among MAU, HTN and gender and ethnicity in Brazilian nondiabetic primary hypertensive patients. Design: Population-based study. Participants: Ninety-eight men and women, seventy-two black and twenty-six white nondiabetic primary hypertensive patients aged 20 years or older were selected. Forty healthy individuals, paired according to age, gender, and ethnics were used as controls. Methods: Early-morning midstream urine was used. Urinary albumin was spectrophotometrically measured with Coomassie Brillant Blue G-250. Creatinine was determined by a method based on Jaffe’s reaction. ACR (μg albumin/mg creatinine) was calculated. Data are expressed as medians. Results: ACR level was significantly higher in 98 hypertensive patients (38.00) than in 40 control individuals (23.00) (P < 0.001). ACR level was significantly higher in 48 hypertensive male (46.00) than in 50 hypertensive female (34.00) (P = 0.008). No significant effect of ethnicity on ACR levels between 26 hypertensive Whites (35.50) and 72 hypertensive Blacks (38.00) was observed (P = 0.978). Conclusions: The ACR level, significantly higher in hypertensive patients than in control individuals, supports data from the literature. To our knowledge, this is the first study demonstrating that the ACR level is significantly higher in men than in women. The lack of an ethnicity effect supports what was already asserted, namely, that in Brazil, at an individual level, color, as determined by physical evaluation, is a poor predictor of genomic African ancestry, as estimated by molecular markers.

Keywords

Albumin Creatinine Rate, Microalbuminuria, Primary Hypertension, Ethnic Groups, Brazilian

Conflicts of Interest

The authors declare no conflicts of interest.

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