ABC | Volume 115, Nº1, July 2020

Original Article Family History of Hypertension Impairs the Autonomic Balance, but not the Endothelial Function, in Young Soccer Players Walter Vargas 1 and Katya Rigatto 1 Universidade Federal de Ciências da Saúde de Porto Alegre, 1 Porto Alegre, RS - Brazil Mailing Address: Walter Vargas • Universidade Federal de Ciências da Saúde de Porto Alegre - Sarmento Leite, 245. Postal Code 90050-170, Porto Alegre, RS – Brazil E-mail: walter.efi@gmail.com Manuscript received December 23, 2018, revised manuscript June 25, 2019, accepted July 17, 2019 DOI: https://doi.org/10.36660/abc.20180441 Abstract Background: The family history of hypertension (FHH) imposes consistent risk for diverse chronic diseases that are accompanied by hypertension. Furthermore, the heart rate variability (HRV) and flow-mediated dilation (FMD) are both related to maximal oxygen uptake (VO 2max ), and are usually impaired during hypertension Objective: To compare the autonomic modulation, the endothelial function (EF) and maximum oxygen uptake (VO 2max ) of young athletes, separated according to their parents’ blood pressure (BP) history, in order to study the influence of their genetic background on those parameters. Methods: A total of 46 young male soccer players (18±2 years of age) were divided into four groups: 1-normotensive father and mother (FM-N); 2-only father was hypertensive (F-H); 3-only mother was hypertensive (M-H); 4-father and mother were hypertensive (FM-H). Measurements of BP, FMD, HRV and VO 2max were performed. The significance level adopted in the statistical analysis was 5%. Results: The standard deviation of normal RR intervals (SDNN; FM-N=314±185; FM-H=182.4± 57.8), the square root of the mean squared differences in successive RR intervals (RMSSD; FM-N=248±134; FM-H=87±51), the number of interval differences of successive NN intervals greater than 50ms (NN50; FM-N=367±83.4; FM-H=229±55), the ratio derived by dividing NN50 by the total number of NN intervals (pNN50; FM-N=32.4±6.2; FM-H=21.1±5.3) and the high (HF; FM-N=49±8.9; FM-H=35.3±12) and low-frequency (LF; FM-N=50.9±8.9; FM-H=64.6±12) components, in normalized units (%), were significantly lower in the FM-H group than in the FM-N group (p<0.05). On the other hand, the LF/HF ratio (ms 2 ) was significantly higher (p<0.05). We found no significant difference between the groups in VO 2max and FMD (p<0.05). Conclusions: In young male soccer players, the FHH plays a potentially role in autonomic balance impairment, especially when both parents are hypertensive, but present no changes in VO 2max and FMD. In this case, there is a decrease in the sympathetic-vagal control, which seems to precede the endothelial damage (Arq Bras Cardiol. 2020; 115(1):52-58) Keywords: Hypertension; Blood Pressure; Heredity/genetics; Soccer; Athletes; Youth Sports; Endothelium/function Introduction Cardiovascular disease is the leading cause of death worldwide. 1 The correlation between blood pressure (BP) and the risk of cardiovascular events is continuous and independent of other risk factors 2 . The latest Guidelines for the management of arterial hypertension established that the optimal values of systolic (SBP) and diastolic BP (DBP) are <120 and 80 mmHg, respectively. 2 Cardiovascular events, such as sudden coronary death, myocardial infarction and stroke might easily occur at pressure even below 139/89mmHg, a threshold considered as normal BP. 3,4 This fact indicates the importance of keeping the BP at lower values. In this context, family history of hypertension emerges as an important predictor of risk to be considered in creating prevention strategies. In fact, professional guidelines for health risk assessment already include the genetic family history. 5 Evidence suggests that the variation of 66% in SBP and 60% in DPB are due to genetic background. 6 Data from the literature have shown that normotensive subjects with a family history of hypertension have lower cardiac parasympathetic modulation and also heart rate variability (HRV). These findings are accompanied by sympathovagal imbalance. 7 Moreover, it has been postulated that this imbalance is associated to increased sympathetic participation, which could be used as a marker for monitoring the cardiovascular system. 8 A decrease in sympathetic modulation helps preventing the risk of premature death, even in non-obese young adults, 9 and should be a goal for treating cardiovascular system diseases. Nevertheless, in healthy young subjects, there is consistent evidence that enhanced parasympathetic activity is associated 52