Heart rate variability (HRV) is a noninvasive method for assessing autonomic function. Age, sex, and chronic conditions influence HRV. Our aim was to evaluate HRV measures exploring differences by age, sex, and race in a sample from a rural area. Analytical sample (n = 1,287) included participants from the 2010 to 2016 evaluation period of the Baependi Heart Study, a family-based cohort in Brazil. Participants underwent 24-hour Holter-ECG (Holter) monitoring. To derive population reference values, we restricted our analysis to a ‘healthy’ subset (i.e. absence of medical comorbidities). A confirmatory analysis was conducted with a subgroup sample that also had HRV derived from a resting ECG 10’-protocol obtained during the same time period. The ‘healthy’ subset included 543 participants. Mean age was 40 ± 14y, 41% were male, 74% self-referred as white and mean body-mass-index was 24 ± 3kg/m2. Time domain HRV measures showed significant differences by age-decade and by sex. Higher values were observed for males across almost all age-groups. Parasympathetic associated variables (rMSSD and pNN50) showed a U-shaped distribution and reversal increase above 60y. Sympathetic-parasympathetic balance variables (SDNN, SDANN) decreased linearly by age. Race differences were no significant. We compared time domain variables with complete data (Holter and resting ECG) between ‘healthy’ versus ‘unhealthy’ groups. Higher HRV values were shown for the ‘healthy’ subset compared with the ‘unhealthy’ group. HRV measures vary across age and sex. A U-shaped pattern and a reversal increase in parasympathetic variables may reflect an age-related autonomic dysfunction even in healthy individuals that could be used as a predictor of disease development.

Recently, some studies have evaluated the role of adiposity measures in the prediction of hypertension risk, but the results are conflicting. Thus, the aim of this study was to compare which of the four indicators of adiposity (waist circumference–WC, body mass index–BMI, body adiposity index–BAI, and visceral adiposity index–VAI) were better associated with hypertension in a Brazilian population. For this study, were selected 1627 individuals (both genders, and aged over 18 years) resident in the municipality of Baependi, a city located in the Southeast of Brazil. WC, BMI, BAI and VAI were determined according to a standard protocol. Hypertension was defined as mean systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg, and/or antihypertensive drug use. The indicators of adiposity WC, BMI, BAI, and VAI were higher in hypertensive when compared to non-hypertensive individuals. In addition, WC and BMI were most strongly associated with hypertension in men and women, respectively. The area under the curve (AUC) of WC was significantly higher than VAI in men. In women, both AUC of BMI and WC showed higher discriminatory power to predict hypertension than BAI and VAI. The indicators of adiposity WC and BMI were better associated with hypertension than BAI and VAI, in both genders, and it could be a useful tools for the screening of hypertensive patients.

Increased arterial stiffness is an important determinant of the risk of cardiovascular disease. Lipid profile impairment, especially hypercholesterolemia, is associated with stiffer blood vessels. Thus, the aim of this study was to determine which of the five circulating lipid components (high-density lipoprotein cholesterol (HDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), low-density lipoprotein cholesterol (LDL), total cholesterol (TC) and triglycerides) is the best predictor of increased arterial stiffness in an urban Brazilian population. A random sample of 1,662 individuals from the general population of Vitoria, Brazil (25-64 years), was selected, and lipid components were measured using standard methods. Pulse wave velocity was measured using a non-invasive automatic device, and increased arterial stiffness was defined as a pulse wave velocity ≥10 m/s. In men, only total cholesterol (OR=1.59; CI=1.02 to 2.48, p=0.04) was associated with the risk of increased arterial stiffness. In women, HDL-C (OR=1.99; CI=1.18 to 3.35, p=0.01) and non-HDL-C (OR=1.61; CI=1.01 to 2.56, p=0.04) were good predictors of the risk of increased arterial stiffness. However, these associations were only found in postmenopausal women (OR=2.06; CI=1.00 to 4.26, p=0.05 for HDL-C and OR=1.83; CI=1.01 to 3.33, p=0.04 for non-HDL-C). Our findings indicate that both HDL-C and non-HDL-C are good predictors of the risk of increased arterial stiffness in postmenopausal women in an urban Brazilian population and may be useful tools for assessing the risk of arterial stiffness.

Given the importance of incorporating simple and low-cost tools into the pediatric clinical setting to provide screening for insulin resistance, the present study sought to investigate whether waist-to-height ratio is comparable to biochemical markers for the discrimination of insulin resistance in children and adolescents. This cross-sectional study involved students from nine public schools. In total, 296 children and adolescents of both sexes, aged 8-14 years, composed the sample. Waist-to-height ratio, triglycerides/glucose index, and triglycerides-to-HDL-C ratio were determined according to standard protocols. Insulin resistance was defined as homeostatic model assessment for insulin resistance with cut-off point ≥ 3.16. Age, body mass index, frequency of overweight, waist circumference, waist-to-height ratio, insulin, glucose, homeostatic model assessment for insulin resistance, triglycerides, triglycerides/glucose index, and triglycerides-to-HDL-C were higher among insulin resistant boys and girls. Moderate correlation of all indicators (waist-to-height ratio, triglycerides/glucose index, and triglycerides-to-HDL-C ratio) with homeostatic model assessment for insulin resistance was observed for both sexes. The areas under the receiver operational characteristic curves ware similar between waist-to-height ratio and biochemical markers. The indicators provided similar discriminatory power for insulin resistance. However, taking into account the cost-benefit ratio, we suggest that waist-to-height ratio may be a useful tool to provide screening for insulin resistance in pediatric populations.

The association between diabetes and obesity is very well established. Faced with this, several anthropometric indices of adiposity are often involved in studies on diabetes. Our main goal in this paper is to evaluate the association between body adiposity index (BAI) and type 2 diabetes mellitus (T2DM) in a sample of the Brazilian population after 5-year follow-up. The data used come from the Baependi Heart Study cohort, which consists of two periods: cycle 1 (2005–2006) and cycle 2 (2010–2013). Individuals of both sexes (n = 1121) were selected by excluding participants with type 2 diabetes mellitus at baseline or those that were lost to follow-up. The diabetic subjects showed higher systolic blood pressure, BAI, body mass index, waist circumference and fasting glucose levels. In addition, using mixed-effects logistic regression, we found that the elevation of a single unit of BAI represented an increase of 8.4% in the risk of a patient developing T2DM (OR = 1.084 [95% CI 1.045–1.124]). Obesity is recognised as one of the most important risk factors for T2DM and BAI has proven to be a useful tool in estimating the risk of a patient developing T2DM in a Brazilian population.