IJCS | Volume 33, Nº4, July and August 2020

Some considerations, however, deserve to be highlighted. It is important to stress that present findings do not allow one to infer the presence of disease or dysfunction in healthy teenager population. All variables showed results within expected normal limits, although significant differences were found between groups. The paired data table of adolescent populations in the study does not inform whether there was also a pairing regarding gender, since it is known that sex can influence HRV. In 2006, Rajendra Acharya et al., 11 observed that HRV is lower with age and that variation is greater in women, particularly during and preceding themenstrual period. It is also necessary when analyzing HRV in a population, that all variables that might affect it in some way should be controlled. In addition to gender, variables such as major or minor component of REM sleep, presence or absence of sleep apnea, would be more useful than just the sleep quality questionnaire, which, in addition to being flawed, does not report relevant sleep data that can influence HRV. Finally, due to the small sample size, these findings must be confirmed later. 1. Lopes P, Oliveira M, André S, Nascimento DLA, Silva SSS, Rebouças GM, et al.et al. Aplicabilidade Clínica da Variabilidade da Frequência Cardíaca. Rev Neurociênc. 2014;21(4):600–3. 2. Wolf MM, Varigos G A, Hunt D SJG. Sinus Arrhythmia in Acute Myocardial Infarction .Med J Aust. 1978;52–3. 3. Kleiger RE, Miller JP, Bigger JT, MossAJ. Decreased heart rate variability and its association with increased mortality after acute myocardial infarction. Am J Cardiol 1987;59(4):256–62. 4. Vanderlei LCM, Pastre CM, Hoshi RA, de Carvalho TD, de Godoy MF. Noções básicas de variabilidade da frequência cardíaca e sua aplicabilidade clínica. Brazilian J Cardiovasc Surg. 2009;24(2):205–17. 5. Barbosa PR, Barbosa Filho J, Sá CAM. Influência da Idade, Sexo e Doença Coronária sobre aModulaçãoAutonômica do Coração.Arq Bras Cardiol. 1996; 67(5): 325-9 6. Nunes NSV. [Contribution to the study of heart rate variability in children without evidences of structural heart disease]. Tese. Rio de Janeiro:Universidade Federal Fluminense, (Cardiologia Clínica);2002.  7. Karayannis G, Giamouzis G, Cokkinos D V., Skoularigis J, Triposkiadis F. Diabetic cardiovascular autonomic neuropathy: Clinical implications. Expert Rev Cardiovasc Ther. 2012;10(6):747–65. 8. Fisher VL, Tahrani AA. Cardiac autonomic neuropathy in patients with diabetes mellitus: Current perspectives. Diabetes, Metab Syndr Obes Targets Ther. 2017;10:419–34. 9. Balcıoğlu AS. Diabetes and cardiac autonomic neuropathy: Clinical manifestations, cardiovascular consequences, diagnosis and treatment. World J Diabetes. 2015;6(1):80. 10. Dias-Filho CA, Soares Jr NJ, Dias CJ, et. al. Influence of Family History of Diabetes on Cardiac Autonomic Dysfunction of Adolescents. Int J Cardiovasc Sci. 2020; 33(4):360-367. DOI: 10.36660/ijcs.20180064 11. Acharya UR, Joseph KP, Kannathal N, Lim CM, Suri JS. Heart rate variability: A review. Med Biol Eng Comput 2006;44(12):1031–51. References 370 Nunes & Benchimol-Barbosa Autonomic modulation in hereditary diseases Int J Cardiovasc Sci. 2020; 33(4):368-370 Editorial