Browsing by Subject "heart rate variability"

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  • Korkalainen, Noora; Mäkikallio, Timo; Räsänen, Juha; Huikuri, Heikki; Mäkikallio, Kaarin (2021)
    Background: According to epidemiological studies, impaired intrauterine growth increases the risk for cardiovascular morbidity and mortality in adulthood. Heart rate variability (HRV), which reflects the autonomic nervous system function, has been used for risk assessment in adults while its dysfunction has been linked to poor cardiovascular outcome. Objective: We hypothesized that children who were born with fetal growth restriction (FGR) and antenatal blood flow redistribution have decreased HRV at early school age compared to their gestational age matched peers with normal intrauterine growth. Study design: A prospectively collected cohort of children born with FGR (birth weight = -2SD. Conclusions: Early school age children born with FGR and intrauterine blood flow redistribution demonstrated altered heart rate variability. These prenatal and postnatal findings may be helpful in targeting preventive cardiovascular measures in FGR.
  • Somppi, Sanni; Törnqvist, Heini; Koskela, Aija; Vehkaoja, Antti; Tiira, Katriina; Väätäjä, Heli; Surakka, Veikko; Vainio, Outi; Kujala, Miiamaaria (2022)
    Simple Summary The relationship between owner and the dog affects the dog's attachment behaviors and stress coping. In turn, the quality of the relationship may affect owner's interpretations about their dog's behavior. Here, we assessed dogs' emotional responses from heart rate variability and behavioral changes during five different situations. Dog owners evaluated the emotion (valence and arousal) of their dog after each situation. We found that both negative and positive incidents provoked signs of emotional arousal in dogs. Owners detected the dog's arousal especially during fear- and stress-evoking situations. The dog-owner relationship did not affect owners' interpretation of dogs' emotion. However, the dog-owner relationship was reflected in the dog's emotional reactions. Close emotional bond with the owner appeared to decrease the arousal of the dogs. Dog owners' frequent caregiving of their dog was associated with increased attachment behaviors and heightened arousal of dogs. Owners rated the disadvantages of the dog relationship higher for the dogs that were less owner-oriented and less arousable. Dog's arousal may provoke dog's need to seek human attention, which in turn may promote the development of emotional bond. We evaluated the effect of the dog-owner relationship on dogs' emotional reactivity, quantified with heart rate variability (HRV), behavioral changes, physical activity and dog owner interpretations. Twenty nine adult dogs encountered five different emotional situations (i.e., stroking, a feeding toy, separation from the owner, reunion with the owner, a sudden appearance of a novel object). The results showed that both negative and positive situations provoked signs of heightened arousal in dogs. During negative situations, owners' ratings about the heightened emotional arousal correlated with lower HRV, higher physical activity and more behaviors that typically index arousal and fear. The three factors of The Monash Dog-Owner Relationship Scale (MDORS) were reflected in the dogs' heart rate variability and behaviors: the Emotional Closeness factor was related to increased HRV (p = 0.009), suggesting this aspect is associated with the secure base effect, and the Shared Activities factor showed a trend toward lower HRV (p = 0.067) along with more owner-directed behaviors reflecting attachment related arousal. In contrast, the Perceived Costs factor was related to higher HRV (p = 0.009) along with less fear and less owner-directed behaviors, which may reflect the dog's more independent personality. In conclusion, dogs' emotional reactivity and the dog-owner relationship modulate each other, depending on the aspect of the relationship and dogs' individual responsivity.
  • Pradhapan, Paruthi; Tarvainen, Mika P.; Nieminen, Tuomo; Lehtinen, Rami; Nikus, Kjell; Lehtimaki, Terho; Kahonen, Mika; Viik, Jari (2014)
  • Ollila, Meri-Maija; Kiviniemi, Antti; Stener-Victorin, Elisabet; Tulppo, Mikko; Puukka, Katri; Tapanainen, Juha; Franks, Stephen; Morin-Papunen, Laure; Piltonen, Terhi (2019)
    OBJECTIVES: Previous studies of women in their 20s and 30s have reported impaired autonomic function in women with polycystic ovary syndrome (PCOS). We aimed to study, for the first time, whether PCOS is associated with impaired cardiac autonomic function independent of metabolic and hormonal status in their late reproductive years. DESIGN: A prospective Northern Finland Birth Cohort 1966 (NFBC1966) study including 5889 women born in 1966 and followed through the age of 46. At that age, n=3706/5123 women (72%) answered the postal questionnaires and n=3280/5123 women (64%) participated in the clinical examination. SETTING: General community. PARTICIPANTS: The sample included women presenting both irregular menses (oligomenorrhoea or amenorrhoea) and hirsutism at age 31 (n=125) or with formally diagnosed PCOS by age 46 (n=181) and women without PCOS symptoms or diagnosis (n=1577). PRIMARY AND SECONDARY OUTCOME MEASURES: Heart rate variability parameters: the root mean square of successive R-R differences (rMSSD), spectral power densities (LF: low frequency and HF: high frequency) and baroreflex sensitivity (BRS). RESULTS: We found that parasympathetic activity (assessed by rMSSD: 19.5 (12.4; 31.9) vs 24.3 (16.1; 34.8) ms, p=0.004 and HF: 172 (75; 399) vs 261 (112; 565) ms(2), p=0.002) and BRS (6.13±3.12 vs 6.99±3.52 ms/mm Hg, p=0.036) were lower in women with PCOS compared with the controls. However, in the multivariate regression analysis, PCOS, body mass index and the free androgen index did not significantly associate with rMSSD, whereas blood pressure, insulin resistance and triglycerides did. CONCLUSIONS: We report here for the first time that late reproductive-aged women with PCOS display impaired cardiac autonomic function manifested as decreased vagal activity. Metabolic status, rather than hyperandrogenaemia and PCOS per se, was the strongest contributing factor. Given the link between cardiac morbidity and impaired autonomic function, the findings underline the importance of screening and treating metabolic abnormalities early on in women with PCOS.
  • Hein, Emil (Helsingin yliopisto, 2022)
    Poor quality of sleep and the following health problems affecting daily life are in many cases caused by cognitive and physiological arousal resulted from a stressful event. Such stress detrimental to sleep may originate from psychosocial factors such as feelings of shame and social rejection. Our goal was to elucidate the impact of acute psychosocial stress occurring before bedtime on sleep macrostructure and the early night non-rapid eye movement sleep (NREMS). In addition, virtual reality solutions are emerging as options to simulate social threats in laboratory environments. We studied whether a virtual reality variation of a public speaking scenario was sufficient in producing a physiological stress response evident in heart rate variability (HRV) parameters. We compared two experimental groups of healthy young adults (n=34), which differed in the scenario completed within the virtual reality. The stress condition involved a public speaking simulation in front of an attentive virtual audience whereas the control condition involved listening to a neutral presentation in the same but empty virtual seminar room. The participants’ physiological responses were measured with a HRV monitor for 38 hours and the quality of sleep during the laboratory night following stress induction with electroencephalography (EEG). The examined early sleep period was divided into two separate cycles of NREMS, whose results were juxtaposed. For analysing frequency band activity during sleep, we processed the data from EEG with Fourier transformation to yield power spectral density values i.e. frequency activity values. Comparing the two conditions, we observed a distinct effect of stress both during the virtual public speaking scenario and in the subsequent early sleep in the participants from the stress group. We found a significant increase in heart rate and rising fluctuations in the LF/HF (HRV power spectrum high frequency/low frequency) ratio around the stress task period contrasting the results of the control condition, reflecting increased sympathetic tone in the stress group. In the following night, the percentage of stage N3 sleep significantly increased at the cost of N2 sleep during the first NREMS cycle in the stress condition, but this effect resolved in the second NREMS cycle where group differences were absent. As a key finding, the stress group exhibited higher beta frequency activity in proportion to delta activity throughout both cycles and sleep stages. This effect was significantly magnified in N3 sleep where the delta/beta activity ratio decreased in the stress group from cycle 1 to 2, indicating worsening quality of sleep as the night progressed. We reflected our results through a homeostatic point of view, where the increased high frequency beta activity at sleep onset and early sleep in the stress group might explain their increased N3 sleep duration in the first NREMS cycle. A stronger affinity for the important N3 sleep may be a sleep protective mechanism to counter the stress induced abnormally high frequency EEG activity at sleep onset and early sleep to ensure the restorative benefits of slow-wave activity.
  • Orjatsalo, Maija; Alakuijala, Anniina; Partinen, Markku (2020)
    Introduction:Postural tachycardia syndrome (POTS) is a suspected dysautonomia with symptoms of orthostatic intolerance and abnormally increased heart rate while standing. We aimed to study cardiac autonomic nervous system functioning in head-up tilt (HUT) in adolescents with POTS to find out if parasympathetic tone is attenuated in the upright position. Methods:We compared characteristics of a group of 25 (females 14/25; 56%) adolescents with POTS and 12 (females 4/12; 34%) without POTS aged 9-17 years. We compared heart rate variability with high- and low-frequency oscillations, and their temporal changes in HUT. Results:The high-frequency oscillations, i.e., HF, attenuated in both groups during HUT (p<0.05), but the attenuation was bigger in POTS (p= 0.04). In the beginning of HUT, low-frequency oscillations, i.e., LF, increased more in POTS (p= 0.01), but in the end of HUT, an attenuation in LF was seen in the POTS group (p<0.05), but not in the subjects without POTS. There were no associations of previous infections or vaccinations with POTS. Subjects with POTS were sleepier and their overall quality of life was very low. Conclusion:The results imply to an impaired autonomic regulation while standing in POTS, presenting as a lower HF and higher LF in the beginning of HUT and an attenuated LF in the prolonged standing position.
  • Frondelius, Lilli; Hietaoja, Juha Kalevi; Pastell, Matti; Hänninen, Laura Talvikki; Anttila, Paula; Mononen, Jaakko (2018)
    This Research Communication describes the effect of post-operative pain and non-steroidal anti-inflammatory drug (NSAID) treatment on heart rate variability (HRV) of dairy cows. Postoperative pain in farm animals is often left untreated, and HRV could be a promising tool for assessing pain. The aim of this study was to assess if postoperative state after subcutaneous surgery affects HRV in dairy cows and to determine whether this could be modulated by NSAID. Nine cows were inserted with an implantable electrocardiograph logger. Cows were divided into the NSAID treatment group and the control group. The cows in the NSAID group had higher HRV than the control group, indicating a higher sympathetic activity in control animals, most likely due to untreated post-operative pain. Besides the ethical need for treating pain in production animals, ongoing pain has an adverse effect on animal productivity. Thus post-operative pain alleviation is recommended.
  • Hietaoja, Juha (Helsingfors universitet, 2012)
    The heart rate of an individual varies all the time. This phenomenon is called heart rate variability. Both respiration and physical activity induce variations in heart rate. Heart rate variability can be assessed by studying electrical changes in the heart cycle. Electrical changes can be monitored by measuring ECG (electrocardiography). The main target of this study was to find out cow’s normal heart rate variability while they were awake, ruminating or sleeping. For this study, the heart rate of nine cows was recorded as well as their behavior during that time. Cows were monitored while they were sleeping, ruminating, standing or lying down. Four of the cows were from Finland and five of them from Sweden. From those nine cows, 543 one minute samples were obtained. This was the first time that cow’s heart rate was studied during their sleep cycle. The cows were not stressed in any way and their autonomic nervous system was not affected by drugs. One minute samples were analyzed. Samples were gathered by using a Matlab-based computer program, CowSS. All samples were checked visually, and all errors, for instance missing S-peaks or the errors caused by timing, were corrected. Statistical analysis was made by using a linear mixed effects model. According to the analysis, the best way to represent a cow’s heart rate variability is to use RMSSD-value. RMSSD-value describes the variations of adjacent intervals in different recordings. The result of this study show that during sleep the heart rate and the heart variability of cows are different from humans´. Cows´ sleep periods (NREM- and REM-sleep) are shorter and during REM-sleep the parasympathetic toning is stronger in cows. Cow is herbivore and prey for many predators, which may well explain the dominance of the parasympathetic system. Parasympathetic toning works faster than sympathetic toning, and this may give the cow a better chance to escape.
  • Martikainen, Joni (Helsingfors universitet, 2016)
    Depression is a phenomenon determined by multiple factors and it can be conceptualized both from psychological and physiological point of view. Psychological and physiological risk factors form a vulnerability that predispose to depression. The purpose of this study was to research the relationship between the psychological risk factors of depression and physiological stress reactivity. Cloninger's temperament trait harm-avoidance (Temperament and Character Inventory) and tendency for ruminative thinking (Self-rumination Scale) were used as psychological risk factors in this study. The physiological stress reactivity was measured by the individual differences in the heart rate variability. 58 women were invited to laboratory based on the earlier web-based study (n=588). In laboratory the women answer to self-report questionnaires and their EKG was measured under a stressful task. Study found a statistically significant association between psychological risk factors of depression and physiological stress reactivity. Psychological risk factors of depression constituted a whole that predicted physiological stress reactivity in a specific experimental setting in a statistically significant way. The results of this study can be used as a foundation for the development of more effective medical interventions and psychotherapies, and for the development of more specific categorization of depressive subcategories.
  • Seipäjärvi, Santtu M.; Tuomola, Anniina; Juurakko, Joona; Rottensteiner, Mirva; Rissanen, Antti-Pekka E.; Kurkela, Jari L. O.; Kujala, Urho M.; Laukkanen, Jari A.; Wikgren, Jan (2022)
    Objective. Autonomic nervous system function and thereby bodily stress and recovery reactions may be assessed by wearable devices measuring heart rate (HR) and its variability (HRV). So far, the validity of HRV-based stress assessments has been mainly studied in healthy populations. In this study, we determined how psychosocial stress affects physiological and psychological stress responses in both young (18-30 years) and middle-aged (45-64 years) healthy individuals as well as in patients with arterial hypertension and/or either prior evidence of prediabetes or type 2 diabetes. We also studied how an HRV-based stress index (Relax-Stress Intensity, RSI) relates to perceived stress (PS) and cortisol (CRT) responses during psychosocial stress. Approach. A total of 197 participants were divided into three groups: (1) healthy young (HY, N = 63), (2) healthy middle-aged (HM, N = 61) and (3) patients with cardiometabolic risk factors (Pts, N = 73, 32-65 years). The participants underwent a group version of Trier Social Stress Test (TSST-G). HR, HRV (quantified as root mean square of successive differences of R-R intervals, RMSSD), RSI, PS, and salivary CRT were measured regularly during TSST-G and a subsequent recovery period. Main results. All groups showed significant stress reactions during TSST-G as indicated by significant responses of HR, RMSSD, RSI, PS, and salivary CRT. Between-group differences were also observed in all measures. Correlation and regression analyses implied RSI being the strongest predictor of CRT response, while HR was more closely associated with PS. Significance. The HRV-based stress index mirrors responses of CRT, which is an independent marker for physiological stress, around TSST-G. Thus, the HRV-based stress index may be used to quantify physiological responses to psychosocial stress across various health and age groups.
  • Ylikoski, Jukka; Lehtimaki, Jarmo; Pirvola, Ulla; Makitie, Antti; Aarnisalo, Antti; Hyvarinen, Petteri; Ylikoski, Matti (2017)
    Conclusion: Transcutaneous vagal nerve stimulation (tVNS) might offer a targeted, patient-friendly, and low-cost therapeutic tool for tinnitus patients with sympathovagal imbalance. Objectives: Conventionally, VNS has been performed to treat severe epilepsy and depression with an electrode implanted to the cervical trunk of vagus nerve. This study investigated the acute effects of tVNS on autonomic nervous system (ANS) imbalance, which often occurs in patients with tinnitus-triggered stress. Methods: This study retrospectively analysed records of 97 patients who had undergone ANS function testing by heart rate variability (HRV) measurement immediately before and after a 15-60min tVNS stimulation. Results: The pre-treatment HRV recording showed sympathetic preponderance/reduced parasympathetic activity in about three quarters (73%) of patients. Active tVNS significantly increased variability of R-R intervals in 75% of patients and HRV age was decreased in 70% of patients. Either the variability of R-R intervals was increased or the HRV age decreased in 90% of the patients. These results indicate that tVNS can induce a shift in ANS function from sympathetic preponderance towards parasympathetic predominance. tVNS caused no major morbidity, and heart rate monitoring during the tVNS treatment showed no cardiac or circulatory effects (e.g. bradycardia) in any of the patients.