longitudinal changes
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2022 ◽  
Vol 12 ◽  
Author(s):  
Chenbin Ma ◽  
Haoran Xu ◽  
Muyang Yan ◽  
Jie Huang ◽  
Wei Yan ◽  
...  

Background: The autonomic nervous system (ANS) is crucial for acclimatization. Investigating the responses of acute exposure to a hypoxic environment may provide some knowledge of the cardiopulmonary system’s adjustment mechanism.Objective: The present study investigates the longitudinal changes and recovery in heart rate variability (HRV) in a young healthy population when exposed to a simulated plateau environment.Methods: The study followed a strict experimental paradigm in which physiological signals were collected from 33 healthy college students (26 ± 2 years, 171 cm ± 7 cm, 64 ± 11 kg) using a medical-grade wearable device. The subjects were asked to sit in normoxic (approximately 101 kPa) and hypoxic (4,000 m above sea level, about 62 kPa) environments. The whole experimental process was divided into four stable resting measurement segments in chronological order to analyze the longitudinal changes of physical stress and recovery phases. Seventy-six time-domain, frequency-domain, and non-linear indicators characterizing rhythm variability were analyzed in the four groups.Results: Compared to normobaric normoxia, participants in hypobaric hypoxia had significantly lower HRV time-domain metrics, such as RMSSD, MeanNN, and MedianNN (p < 0.01), substantially higher frequency domain metrics such as LF/HF ratio (p < 0.05), significantly lower Poincaré plot parameters such as SD1/SD2 ratio and other Poincaré plot parameters are reduced considerably (p < 0.01), and Refined Composite Multi-Scale Entropy (RCMSE) curves are reduced significantly (p < 0.01).Conclusion: The present study shows that elevated heart rates, sympathetic activation, and reduced overall complexity were observed in healthy subjects exposed to a hypobaric and hypoxic environment. Moreover, the results indicated that Multiscale Entropy (MSE) analysis of RR interval series could characterize the degree of minor physiological changes. This novel index of HRV can better explain changes in the human ANS.


Healthcare ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 144
Author(s):  
Herman de Vries ◽  
Wim Kamphuis ◽  
Cees van der Schans ◽  
Robbert Sanderman ◽  
Hilbrand Oldenhuis

The emergence of wearable sensors that allow for unobtrusive monitoring of physiological and behavioural patterns introduces new opportunities to study the impact of stress in a real-world context. This study explores to what extent within-subject trends in daily Heart Rate Variability (HRV) and daily HRV fluctuations are associated with longitudinal changes in stress, depression, anxiety, and somatisation. Nine Dutch police officers collected daily nocturnal HRV data using an Oura ring during 15–55 weeks. Participants filled in the Four-Dimensional Symptoms Questionnaire every 5 weeks. A sample of 47 five-week observations was collected and analysed using multiple regression. After controlling for trends in total sleep time, moderate-to-vigorous physical activity and alcohol use, an increasing trend in the seven-day rolling standard deviation of the HRV (HRVsd) was associated with increases in stress and somatisation over 5 weeks. Furthermore, an increasing HRV trend buffered against the association between HRVsd trend and somatisation change, undoing this association when it was combined with increasing HRV. Depression and anxiety could not be related to trends in HRV or HRVsd, which was related to observed floor effects. These results show that monitoring trends in daily HRV via wearables holds promise for automated stress monitoring and providing personalised feedback.


2022 ◽  
Vol 158 ◽  
pp. 107018
Author(s):  
Hui-Ju Tsai ◽  
Chia-Fang Wu ◽  
Chao A. Hsiung ◽  
Chieng-Hung Lee ◽  
Shu-Li Wang ◽  
...  

Diabetologia ◽  
2021 ◽  
Author(s):  
Milana A. Bochkur Dratver ◽  
Juliana Arenas ◽  
Tanayott Thaweethai ◽  
Chu Yu ◽  
Kaitlyn James ◽  
...  

2021 ◽  
Vol 13 ◽  
Author(s):  
Tien Viet Pham ◽  
Daiki Sasabayashi ◽  
Tsutomu Takahashi ◽  
Yoichiro Takayanagi ◽  
Manabu Kubota ◽  
...  

Previous magnetic resonance imaging (MRI) studies reported increased brain gyrification in schizophrenia and schizotypal disorder, a prototypic disorder within the schizophrenia spectrum. This may reflect deviations in early neurodevelopment; however, it currently remains unclear whether the gyrification pattern longitudinally changes over the course of the schizophrenia spectrum. The present MRI study using FreeSurfer compared longitudinal changes (mean inter-scan interval of 2.7 years) in the local gyrification index (LGI) in the entire cortex among 23 patients with first-episode schizophrenia, 14 with schizotypal disorder, and 39 healthy controls. Significant differences were observed in longitudinal LGI changes between these groups; the schizophrenia group exhibited a progressive decline in LGI, predominantly in the fronto-temporal regions, whereas LGI increased over time in several brain regions in the schizotypal and control groups. In the schizophrenia group, a greater reduction in LGI over time in the right precentral and post central regions correlated with smaller improvements in negative symptoms during the follow-up period. The cumulative medication dosage during follow-up negatively correlated with a longitudinal LGI increase in the right superior parietal area in the schizotypal group, but did not affect longitudinal LGI changes in the schizophrenia group. Collectively, these results suggest that gyrification patterns in the schizophrenia spectrum reflect both early neurodevelopmental abnormalities as a vulnerability factor and active brain pathology in the early stages of schizophrenia.


Neurology ◽  
2021 ◽  
pp. 10.1212/WNL.0000000000013250
Author(s):  
Deanne Thompson ◽  
Joseph Yuan-Mou Yang ◽  
Jian Chen ◽  
Claire Kelly ◽  
Christopher L Adamson ◽  
...  

Objective:To investigate brain regional white matter development in full-term (FT) and very preterm (VP) children at term-equivalent, 7 and 13 years of age based on the ratio of T1-weighted and T2-weighted magnetic resonance images (T1-w/T2-w), including: (1) whether longitudinal changes differ between birth groups or sexes; (2) associations with perinatal risk factors in VP children, and; (3) relationships with neurodevelopmental outcomes at 13 years.Methods:Prospective longitudinal cohort study of VP (born <30 weeks’ gestation or <1250 g) and FT infants born between 2001-2004 and followed up at term-equivalent age, 7 years of age and 13 years of age, including magnetic resonance imaging studies and neurodevelopmental assessments. T1-w/T2-w images were parcellated into 48 white matter regions of interest.Results:Of 224 VP participants and 76 FT participants, 197 VP and 55 FT participants had usable T1-w/T2-w data from at least one timepoint. T1-w/T2-w values increased between term-equivalent and 13 years of age, with little evidence that longitudinal changes varied between birth groups or sexes. VP birth, neonatal brain abnormalities, being small for gestational age and postnatal infection were associated with reduced regional T1-w/T2-w values in childhood and adolescence. Increased T1-w/T2-w values across the white matter at 13 years were associated with better motor and working memory function for all children. Within the FT group only, larger increases in T1-w/T2-w values from term-equivalent to 7 years were associated with poorer attention and executive function, and higher T1-w/T2-w values at 7 years were associated with poorer mathematics.Conclusion:VP birth and multiple known perinatal risk factors are associated with long-term reductions in the T1-w/T2-w ratio in white matter regions in childhood and adolescence, which may relate to alterations in microstructure and myelin content. Furthermore, increased T1-w/T2-w ratio at 13 years appeared to be associated with better motor and working memory function, and there appeared to be developmental differences between VP and FT children in the associations for attention, executive functioning and mathematics.


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