Racial differences in HbA1c: a cross-sectional analysis of a Brazilian public primary care population.

BACKGROUND: Blacks show higher levels of HbA1c in studies with different populations and are disproportionately affected by most diabetes-related complications. AIMS: The study aims to investigate if the prevalence of altered glycated hemoglobin (HbA1c) varies with skin color and if there is a familial aggregation of either skin color and HbA1c. METHODS: The study used the CAMELIA study (Cardio-Metabolic-Renal familiar) population, conducted between June 2006 and December 2007 (cross sectional). Families were recruited from 13 Family Doctor Program Unities of Niteroi, Brazil, a highly miscegenated population. The visits included questionnaire, medical consultation, anthropometric and nutritional assessment. Blood pressure, blood/urine samples were collected. The dosage of HbA1c was performed by immunoturbidimetry in Labmax 240 equipment. RESULTS: We compare data of 241 (25.5%) Blacks, versus 422 (44.7%) Mulattos or 272 (28.8%) Whites. The groups did not differ significantly with regard to most measures. Blacks had the lowest levels of income/education, higher frequency of diabetes and hypertension (p<0.20) as higher levels of HbA1c (p<0.05) that persisted after adjusting for possible confounders. Among blacks, the correlations between siblings of HbA1c were higher than among white/mulatto, reaching 86% versus 50%, respectively. CONCLUSION: Those results indicate that Brazilian Blacks patients must have more attention, focusing on diabetes preventive care. Longitudinal studies are needed to address the question if the altered level of HbA1c has a real clinical impact.

Prehypertension and cardiovascular risk factors in adults enrolled in a primary care programme.

BACKGROUND: An increase in cardiovascular (CV) disease has been observed in prehypertensive subjects who frequently carry other cardiovascular risk factors. In Brazil, little is known about prehypertension and its association with cardiovascular risk factors. OBJECTIVE: To estimate the association between prehypertension and cardiovascular risk factors in a public primary healthcare programme. METHODS: Associations in this cross-sectional study were estimated on the basis of generalized estimating equations. Results are expressed as odds ratio (OR) or adjusted odds ratio (OR(a)) with 95% confidence interval (CI). RESULTS: The 357 participants were classified as normotensive (64.4%) or prehypertensive (35.6%). In a univariate analysis, prehypertension was statistically associated with male gender, age, table salt use, diabetes, body mass index (BMI), uric acid, and all lipids except high-density lipoprotein cholesterol. When analysis was performed adjusting for gender, age, and table salt use, the association of each metabolic parameter with prehypertension, remained significant for BMI (OR(a) = 1.097; 95% CI 1.035-1.162), triglycerides (OR(a) = 1.008; 95% CI 1.003-1.013), and uric acid (OR(a) = 1.269; 95% CI 1.023- .576). To check for their independence of obesity, associations of triglycerides and uric acid with prehypertension were reanalysed after adjustment for BMI. The association of triglycerides remained statistically significant. A trend of association was present for uric acid. The prevalence of prehypertension paralleled the increase of the number of risk factors. CONCLUSION: Prehypertension in Brazil is associated with well-recognized cardiovascular risk factors even in a continuously monitored population such the one under study. Prehypertension can be a valuable clue to alert health professionals to treat underlying perturbations to prevent overt cardiovascular disease.