Influence of age and gender on autonomic regulation of heart

Abstract

Heart rate variability (HRV) is a non-invasive method to measure cardiac autonomic function. Impairments in HRV have been proposed as independent risk factor for increased cardiac mortality and morbidity. Cardio protective phenomenon in females has been hypothesized to be due to differential autonomic tone. Age related loss of vagal control has been reported as predisposing factor for the development of cardiovascular disease. In this study we assessed effect of age and gender on autonomic regulation of heart in healthy volunteers. HRV data of 189 subjects (114 males and 75 females) were analyzed in time and frequency domains using customized program. Artifact free 5 min electrocardiogram segment was used for analysis. It was ensured that none of the subject had medical illness such as diabetes, hypertension, thyroid disorders, cardiac disorders, diseases potentially related with autonomic neuropathy and major psychiatric illness by careful history and clinical examination. HRV recordings were done under standard laboratory condition. On correlation analysis SDNN, RMSSD, total power negatively correlated with age suggesting reduced autonomic regulation of heart with increase in age (SDNN: r = -0.444, p < 0.01; RMSSD: r = -0.552, p < 0.01; total power: r = -0.474, p < 0.01); similarly High frequency power (HF.nu) negatively correlated with age (r = -0.167, p = 0.02), denoting loss of vagal tone with aging. LF/HF ratio correlated positively with age (r = 0.19, p < 0.01) suggesting a relative increase of sympathetic activity with increase in age. On multiple regression analysis to control for effect of age and heart rate while comparing males and females, LF.nu showed significant reduction suggesting lower sympathetic tone in females (β = -6.64; p < 0.01) and HF.nu showed increase at trend level (β = 4.47; p = 0.053). In conclusion, there is overall reduction in autonomic control of heart with increase in the age. Sympathetic tone predominates and vagal tone diminishes with aging process. Females showed greater vagal tone than male. This differential autonomic tone indicate age, gender related predisposition to cardiovascular disease.

Impact of type of intervention for aortic valve replacement on heart rate variability

“…Perioperative hemodynamic instability, that has been described in patients with cardiac dysautonomia due for instance to diabetes [31], is likely to occur also in patients after surgical aortic valve replacement. Special attention is therefore advisable for patients with possible coexisting cardiac autonomic impairments, such as subjects with more advanced age, previous myocardial infarction, diabetes mellitus, Parkinson's disease [31][32][33][34]. Besides the usual criteria for the choice of type of approach for aortic valve replacement, diseases possibly associated with autonomic disorders should also be considered.…”

Einfluss einer posttraumatischen Belastungsstörung auf die Herzfrequenzvariabilität als Marker des autonomen Nervensystems – eine systematische Literaturübersicht

“…So ist die Studienlage hinsichtlich einer erhöhten sympathischen bzw. parasympathischen Grundaktivität beim Geschlecht zwar noch nicht eindeutig [21 -23], hingegen ist die HRV im jungen Erwachsenenalter am höchs-ten und fällt mit zunehmendem Lebensalter ab [23]. Darüber hinaus sind zahlreiche chronische Erkrankungen bekannt, die die HRV reduzieren [18], u. a. Diabetes mellitus [24], eine koronare Herzerkrankung und/oder ein stattgehabter Myokardinfarkt [25].…”

Factors influencing heart rate variability

“…A person's HRV first increases sharply until they reach the age of one and continues to increase considerably until they reach the age of 15, while the resting heart rate decreases 15 . Their HRV then decreases as they grow older [16][17][18] . It also seems clear that there is a difference between men and women in the way the autonomous nervous system is regulated and thus in the sympathetic-parasympathetic balance, and this manifests itself in differing HRVs 16,[19][20][21][22][23][24][25][26] .…”

“…Their HRV then decreases as they grow older [16][17][18] . It also seems clear that there is a difference between men and women in the way the autonomous nervous system is regulated and thus in the sympathetic-parasympathetic balance, and this manifests itself in differing HRVs 16,[19][20][21][22][23][24][25][26] . This difference between the genders seems to become less prominent when people reach the age of 50, a fact that is attributed to the postmenopausal hormonal changes that take place in women 27,28 .…”