Published: 2016-12-24

Analysis of cardiac autonomic modulation in normotensive obese and eutrophic adults of Nepal

Ram Lochan Yadav, Rita Khadka, Kopila Agrawal, Dilip Thakur, Deepak Sharma, Dev Kumar Shah, Prakash Kumar Yadav, Niraj Khatri Sapkota, Bishnu Hari Paudel, Md. Nazrul Islam


Background: Obese people have a higher prevalence of cardiovascular disease, though unknown mechanism, supposed to be due to autonomic dysfunction which is still in controversy. This study aimed to assess and compare heart rate variability (HRV) between normotensive obese and adults.

Methods: The study was conducted on 30 normotensive obese adults (mean age 32.07±7.25 years) with BMI>30 and 29 age- and sex-matched normal weight controls (mean age 30.48±8.01 years) with BMI: 18-24 Kg/m2. Short-term HRV variables were assessed using standard protocol. The data were compared between the groups using Mann Whitney ‘U’ test.

Results: In obese group, there was significant increase in the mean heart rate [79.17±8.80 Vs 71.48±8.41 beats/min, p=0.001], systolic blood pressure [121.20±9.89 Vs 113.24±11.07, mmHg, p=0.004] and diastolic blood pressure [84.97±7.87 Vs 74.83±10.31 mmHg, p=0.000]. The HRV parasympathetic indicators were less [RMSSD {28.75(16.72-38.35) Vs 41.55(30.6-56.75) ms, p=0.018}, NN50 {15.5(2-39) Vs 83.5(32.75-116.25), p=0.010}], and sympathetic indicator LF/HF ratio [1.2(0.65-2.20) Vs 0.79(0.5-1.02), p=0.004] was more in obese group.

Conclusions: Obese persons have increased sympathetic activity with a reduction in parasympathetic (vagal) tone indicating poor autonomic cardiac rhythm control. Moreover, the altered autonomic activity could be the reason for increased mean heart rate and blood pressures in normotensive obese persons.


Obesity, Heart rate variability, Body mass index, Autonomic nervous system, Normotensive obese

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Balarajan Y, Villamor E. Nationally representative surveys show recent increases in the prevalence of overweight and obesity among women of reproductive age in Bangladesh, Nepal, and India. J. Nutr. 2009;139:2139-44.

Daniels SR. Complications of obesity in children and adolescents. Int J Obesity. 2009;33(Suppl 1):S60-5.

Lee YS. Consequences of childhood obesity. Ann Acad Med Singapore. Ind J Nutr. 2009;38:75-81.

Calle EE, Thun MJ, Petrelli JM, Rodriguez C, Heath CW Jr. Body-mass index and mortality in a prospective cohort of US adults. N Engl J Med. 1999;341:1097-105.

Lobstein T, Baur L, Uauy R. IASO International Obesity Task Force. Obesity in children and young people: a crisis in public health. Obes Rev. 2004;5:4-104.

WHO. Obesity: preventing and managing the global epidemic: report of a WHO consultation (ISSN 05 12-3054): WHO; Geneva, Switzerland; 1999. WHO Tech Rep Ser, 894.

Han TS, Sattar N, Lean M. ABC of obesity. Assessment of obesity and its clinical implications. BMJ. 2006;333(7570):695-708.

Obesity: preventing and managing the global epidemic. Report of a WHO consultation. World Health Organ Tech Rep Ser. 2000;894:1-253.

Kaufman CL, Kaiser DR, Steinberger J, Kelly AS, Dengel DR. Relationships of cardiac autonomic function with metabolic abnormalities in childhood obesity. Obesity. 2007;15:1164-71.

Tonhajzerova I, Javorka M, Trunkvalterova Z, Chroma O, Javorkova J,Lazarova Z, et al. Cardio-respiratory interaction and autonomic dysfunction in obesity. J Physiol Pharmac. 2008;59(Supply 6):709-18.

Lown B, Verner RL. Neural activity and ventricular fibrillation. N Engl J Med. 1976;294:1165-70.

Corr PB, Yamada KA, Witkowski FX. Mechanisms controlling cardiac autonomic function and their relation to arrhythmogenesis. In: Fozzard HA, Haber E, Jennings RB, Katz AN, Morgan HE, eds. The Heart and Cardiovascular System. New York: Raven Press. 1986:1343-1403.

Schwartz PJ, Priori SG. Sympathetic nervous system and cardiac arrhythmias. In: Zipes DP, Jalife J, eds. Cardiac Electrophysiology. From Cell to Bedside. Philadelphia: W.B. Saunders. 1990:330-343.

Levy MN, Schwartz PJ eds. Vagal control of the heart: Experimental basis and clinical implications. Armonk: Future, 1994.

Vanderlei LCM, Pastre CM, Hoshi RA, Carvalho TD, Godoy MF. Basic notions of heart rate variability and its clinical applicability. Rev Bras Cir Cardiovasc 2009; 24: 205-217.

Haslam DW, James WP. Obesity. Lancet. 2005;366(9492):1197-209. (WHO/obesity and overweight: fact sheet no.311, Sept. 2006).

The seventh report of the Joint National Committee on the prevention, detection, evaluation, and treatment of high blood pressure. National Heart, Lung, and Blood Institute. August 2004.

Task force of the European Society of Cardiology and The North American Society of Pacing and Electrophysiology. Heart rate variability. Europian Heart Journal. 1996;17:354-84.

Rumantir MS, Vaz M, Jennings GL, Collier G, Kaye DM, Seals DR, et al. Neural mechanisms in human obesity-related hypertension. J Hypertens. 1999;17:1125-33.

Messerli FH, Nunez BD, Ventura HO, Snyder DN. Overweight and sudden death. Arch Intern Med. 1987;147:1725-8.

Grassi G. Debating sympathetic overactivity as a hallmark of human obesity: a pro’s position. J Hypertens. 1999; 17: 1059-1060.

Rabbia F, Silke B, Conterno A, Grosso T, DeVito B, Rabbone I, et al. Assessment of cardiac autonomic modulation during adolescent obesity. Obes Res. 2003;11:541-8.

Riva P, Martini G, Rabbia F, Milan A, Paglieri C, Chiandussi L, et al. Obesity and autonomic function in adolescence. Clin Exp Hypertens. 2001;23:57-67.

Wong CY, O’Moore-Sullivan T, Leano R, Byrne N, Beller E, Marwick TH. Alterations of left ventricular myocardial characteristics associated with obesity. Circulation. 2004;110:3081-7.

Gutin B, Barbeau P, Litakar MS, Ferguson M, Owens S. Heart rate variability in obese children: relations to total body and visceral adiposity, and changes with physical training and detraining. Obes Res. 2000;8:12-9.

Zahorska-Markiewicz B, Kuagowsa E, Kucio C, Klin M. Heart rate variability in obesity. Int J Obes Relat Metab Disord. 1993;17:21-3.

Masuo K, Mikami H, Ogihara T, Tuck ML. Weight gain-induced blood pressure elevation. Hypertension. 2000;35:1135-40.

Macmohan S, Cutler J, Brittain E, Higgins M. Obesity and hypertension: epidemiological and clinical issues. Eur Heart J. 1987;8(suppl B):57-70.

Stamler R, Stamler J, Riedlinger WF, Algera G, Roberts RH. Weight and blood pressure. Findings in hypertension screening of 1 million Americans. JAMA. 1978;240:1607-10.

Laederach-Hofmann K, Mussgay L, Ru´ddel H. Autonomic cardiovascular regulation in obesity. J Endocrinol. 2000;164:59-66.

Peterson HR, Rothschild M, Weinberg CR, Fell RD, McLeish KR, Pfeifer MA. Body fat and the activity of the autonomic nervous system. N Engl J Med. 1988;318:1077-183.

Nagai N, Matsumoto T, Kita H, Moritani T. Autonomic nervous system activity and the state and development of obesity in Japanese school children. Obes Res. 2003;11:25-32.

Nagai N, Moritani T. Effect of physical activity on autonomic nervous system function in lean and obese children. Int J Obesity. 2004;28:27-33.

Marques Vanderlei LC, Pastre CM, Freitas Júnior IF, Fernandes de Godoy M. Geometric Indexes of Heart Rate Variability in Obese and Eutrophic Children. Arq Bras Cardiol. 2010;65(8):789-92.

Hambdy RC. Obesity: an epidemic. South Med J. 2003;96:531-2.

Spraul M, Ravussin E, Fontvieille AM, Rising R, Larson DE, Anderson EA. Reduced sympathetic nervous activity. A potential mechanism predisposing to body weight gain. J Clin Invest. 1993;92(4):1730-5.

Yakinci C, Mungen B, Karabiber H, Tayfun M, Evereklioglu C. Autonomic nervous system functions in obese children. Brain Dev. 2000;22:151-3.