Low birth weight (LBW) has been considered as a risk factor for adult hypertension that is associated with deterioration of autonomic functions and low-grade inflammation. To explore the above effects of LBW, we measured blood pressure (BP) and heart rate variability during postural change from a supine position to a sitting position in 21 healthy Mongolian adults aged 23-34 years: 4 with LBW (birth weight < 2,500 g), 13 with normal birth weight (NBW, 2,500 g ≤ birth weight < 4,000 g), and 4 with high birth weight (HBW, ≥ 4,000 g). Mongolian population is known to have higher prevalence of hypertension. The ratio of low frequency (LF, 0.04-0.15 Hz) to high frequency components (HF, 0.15-0.40 Hz) was used as an index of sympathetic nerve activity, and HF was used as an index of parasympathetic nerve activity. In contrast to the NBW group, the LBW and HBW groups showed no significant increase in heart rate, systolic BP and LF/HF following postural change. We also measured blood cell counts and other blood parameters related to inflammation. After adjusting for age, BMI, sex and family history of hypertension, LBW was retained as an independent predictor only for higher counts of leukocytes (β = −0.51, p < 0.05), basophils (β = −0.62, p < 0.01), eosinophils (β = −0.83, p < 0.001), and platelets (β = −0.61, p < 0.05). We propose that LBW leads to blunted autonomic responses and low-grade inflammation in seemingly healthy Mongolian adults.
Objectives: The aim of this study was to evaluate the effect of the supine, left lateral decubitus, and right lateral decubitus positions on autonomic nervous activity in elderly adults by using spectral analysis of heart rate variability (HRV). Method: Forty-five adults aged 73.6 ± 5.7 years were enrolled. After lying in the supine position, all participants moved to the lateral decubitus positions in a random order and maintained the positions for 10 min, while electrocardiographic data were recorded to measure HRV. Results: The lowest heart rate continued for 10 min when participants were in the left lateral decubitus position compared with the other two positions (p < .001), while the HRV indexes remained unchanged. The low-frequency HRV to high-frequency HRV ratio (LF/HF) for the right lateral decubitus position was significantly lower than that for the other positions. Discussion: The right lateral decubitus position may attenuate sympathetic nerve activity in elderly adults.
It is well known that sex differences in body weight, blood pressure (BP) and heart rate (HR) exist. However, little research has been conducted on sex differences in circulatory effects, including autonomic nervous activity, between various recumbent positions. This study aimed to evaluate whether male and female young adults show differences in circulatory effects and autonomic nervous activity between 3 positions (supine, right lateral, and left lateral decubitus). Twenty‐nine male (22.5 ± 0.5 years) and 29 female (23.1 ± 0.7 years) healthy volunteers participated in this study. We measured HR variability (HRV) and BP in each of the 3 positions for 10 min. Compared to females, males had a significantly higher systolic BP and low frequency‐to‐high frequency component ratio (LF/HF) in all 3 positions. In females, HF was significantly higher than that in males in the right and left lateral decubitus positions. In both sexes, HR was significantly decreased in the left lateral decubitus position compared to the supine position. Interestingly, neither sex showed significant changes in HF and LF/HF during the change from the supine position to the recumbent positions. The results suggest that there are differences in baseline autonomic nervous activity between males and females. However, both sexes have same reaction to postural changes in circulatory dynamics.
The effect of lateral decubitus positions on the autonomic nervous system and circulatory regulation has not been well clarified in normal healthy adults. Our aim was to evaluate whether the left and right lateral decubitus positions affect heart rate variability (HRV), including hemodynamics, compared to the supine position. We non‐invasively measured blood pressure (BP), heart rate (HR), stroke index (SI), cardiac index (CI) and total peripheral resistance index (TPRI) in each posture in 10 nonsmoking healthy volunteers. After lying in the supine position, the subjects maintained each lateral decubitus position in random order for 10 min at an angle of about 45 degrees. The postural change was performed manually by two trained researchers. No significant differences were observed in mean BP, low frequency HRV, high frequency HRV, and their ratio. However, in the left lateral decubitus position, HR was significantly lower than in the supine position. In both lateral decubitus positions, SI and CI tended to decrease compared to the supine position, and an upward trend was noted for TPRI. The HRV results suggest that the both recumbent positions have no influence on the autonomic nervous system. The reduction in HR and SI in the left recumbent position may not be related to autonomic nervous activity.
Low birth weight (LBW) was confirmed as a risk of high blood pressure (BP) in later stages of life (Barker DJ et al, 1989). Low‐grade inflammation and deterioration of autonomic regulation play an important role in hypertension. However, the associations with birth weight are poorly understood. We examined these relationships among Mongolian, Han Chinese and Japanese young adults, and investigated whether ethnicity affected these relationships. We measured BP and heart rate variability at rest and during postural change from a supine to a sitting position in 16 Mongolian, 4 Han Chinese and 21 Japanese healthy volunteers aged 18–34 years. Blood cell counts, and total cholesterol, high‐density lipoprotein cholesterol (HDL‐C), low‐density lipoprotein cholesterol, triglyceride, and high sensitivity C‐reactive protein levels were measured. Mongolians had lower levels of HDL‐C than did the Japanese (p < 0.01) and the Han Chinese. In Mongolians, the platelet count was higher in the LBW group than in the normal birth weight (NBW) group (p < 0.05). Following postural change, systolic blood pressure and heart rate showed no significant increases in the Mongolian and Japanese LBW groups, whereas the NBW groups had normal responses (p < 0.05). The Mongolian LBW group displayed a slight decrease in sympathetic nerve activity from a supine to a sitting position, although it increased in the Japanese LBW group (p < 0.05). These relationships were not able to examine in Han Chinese because of the small sample size. We suggested that Mongolian low birth weight young adults have higher risk of hypertension compared with Han Chinese and Japanese counterparts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.