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Emerging evidence suggests beneficial effects of sauna bathing on the cardiovascular system. However, the effects of sauna bathing on parameters of cardiovascular function and blood-based biomarkers are uncertain. We aimed to investigate whether sauna bathing induces changes in arterial stiffness, blood pressure (BP), and several blood-based biomarkers. We conducted an experimental study including 102 participants (mean age (SD): 51.9 (9.2) years, 56% male) who had at least one cardiovascular risk factor. Participants were exposed to a single sauna session (duration: 30 min; temperature: 73 °C; humidity: 10-20%). Cardiovascular as well as blood-based parameters were collected before, immediately after, and after 30-min recovery. Mean carotid-femoral pulse wave velocity was 9.8 (2.4) m/s before sauna and decreased to 8.6 (1.6) m/s immediately after sauna (p < 0.0001). Mean systolic BP decreased after sauna exposure from 137 (16) to 130 (14) mmHg (p < 0.0001) and diastolic BP from 82 (10) to 75 (9) mmHg (p < 0.0001). Systolic BP after 30 min recovery remained lower compared to pre-sauna levels. There were significant changes in hematological variables during sauna bathing. Plasma creatinine levels increased slightly from sauna until recovery period, whereas sodium and potassium levels remained constant. This study demonstrates that sauna bathing for 30 min has beneficial effects on arterial stiffness, BP, and some blood-based biomarkers. These findings may provide new insights underlying the emerging associations between sauna bathing and reduced risk of cardiovascular outcomes.
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Journal of Human Hypertension (2018) 32:129138
https://doi.org/10.1038/s41371-017-0008-z
ARTICLE
Acute effects of sauna bathing on cardiovascular function
Tanjaniina Laukkanen1Setor K. Kunutsor2Francesco Zaccardi 3Earric Lee 4Peter Willeit 5,6
Hassan Khan7Jari A. Laukkanen 1,8
Received: 1 July 2017 / Revised: 3 September 2017 / Accepted: 19 September 2017 / Published online: 21 December 2017
© Macmillan Publishers Limited, part of Springer nature 2018
Abstract
Emerging evidence suggests benecial effects of sauna bathing on the cardiovascular system. However, the effects of sauna
bathing on parameters of cardiovascular function and blood-based biomarkers are uncertain. We aimed to investigate
whether sauna bathing induces changes in arterial stiffness, blood pressure (BP), and several blood-based biomarkers. We
conducted an experimental study including 102 participants (mean age (SD): 51.9 (9.2) years, 56% male) who had at least
one cardiovascular risk factor. Participants were exposed to a single sauna session (duration: 30 min; temperature: 73 °C;
humidity: 1020%). Cardiovascular as well as blood-based parameters were collected before, immediately after, and after
30-min recovery. Mean carotidfemoral pulse wave velocity was 9.8 (2.4) m/s before sauna and decreased to 8.6 (1.6) m/s
immediately after sauna (p<0.0001). Mean systolic BP decreased after sauna exposure from 137 (16) to 130 (14) mmHg (p
<0.0001) and diastolic BP from 82 (10) to 75 (9) mmHg (p<0.0001). Systolic BP after 30 min recovery remained lower
compared to pre-sauna levels. There were signicant changes in hematological variables during sauna bathing. Plasma
creatinine levels increased slightly from sauna until recovery period, whereas sodium and potassium levels remained
constant. This study demonstrates that sauna bathing for 30 min has benecial effects on arterial stiffness, BP, and some
blood-based biomarkers. These ndings may provide new insights underlying the emerging associations between sauna
bathing and reduced risk of cardiovascular outcomes.
Introduction
Sauna bathing, a form of passive heat therapy, is commonly
used for relaxation and pleasure purposes [1,2]. Repeated
sauna therapy has been shown to increase left ventricular
ejection fraction and reduce plasma levels of norepinephrine
and brain natriuretic peptide and increase the 6-min walk
distance [3]. After 1 week of repeated sauna exposure
(twice a day) in 10 healthy male volunteers, diastolic blood
pressure (DBP) was shown to decrease substantially [4].
Warm water immersion, which is also a form of passive
heat therapy, is associated with health benets that include
improved endothelial and microvascular function as well as
reduced arterial stiffness (AS) and BP [5,6]. Passive heat
therapy (hot tub) improves cutaneous microvascular func-
tion by enhancing nitric oxide-dependent dilation in
sedentary humans [5]. It has been demonstrated that sauna
exposure results elevations in core temperature and changes
in cardiovascular hemodynamics, such as cardiac output
and vascular shear stress, which are similar to the effects of
exercise, and thus may provide an alternative means of
improving health [6]. In a 2-week trial of once-a-day
infrared-sauna exposure for patients with cardiovascular
*Jari A. Laukkanen
jariantero.laukkanen@uef.
1Institute of Public Health and Clinical Nutrition, University of
Eastern Finland, Kuopio, Finland
2Translational Health Sciences, Bristol Medical School, University
of Bristol, Learning and Research 11 Building (Level 1),
Southmead Hospital, Bristol, UK
3Diabetes Research Centre, Leicester General Hospital, University
of Leicester, Leicester, UK
4Department of Biology of Physical Activity, University of
Jyväskylä, Jyväskylä, Finland
5Department of Public Health and Primary Care, University of
Cambridge, Cambridge, UK
6Department of Neurology, Medical University Innsbruck,
Innsbruck, Austria
7Emory University, Atlanta, GA, USA
8Central Finland Health Care District, Department of Internal
Medicine, Jyväskylä, Finland
Electronic supplementary material The online version of this article
(https://doi.org/10.1038/s41371-017-0008-z) contains supplementary
material, which is available to authorized users.
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... A decrease in blood pressure, improved arterial elasticity and a temporary increase in blood cell parameters such 4 as hemoglobin levels, leukocyte and platelet counts were observed. These effects may contribute to long-term protection against arterial stiffness and reduced risk of cardiovascular disease and mortality, as shown in the studies we cited earlier (10). Studies on the effects of sauna bathing show that regular use has numerous benefits for cardiovascular health. ...
... SBP averaged 137 mmHg before the sauna session, 130 mmHg immediately after, and 130 mmHg after 30 minutes of rest. Diastolic blood pressure (DBP) values were 82 mmHg before, 75 mmHg after the sauna bath, and 81 mmHg after a 30-minute rest, respectively, suggesting that sauna bathing may have health benefits for patients with cardiovascular risk factors (10,12). A more recent 2019 study, also conducted on participants without a heavy health history, found similar results. ...
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... Growing evidence demonstrates that whole-body heat therapy may reduce all-cause mortality (Laukkanen et al. 2015(Laukkanen et al. , 2018a, fatal cardiovascular disease (Laukkanen et al. 2015(Laukkanen et al. , 2018a, stroke (Kunutsor et al. 2018), dementia , and respiratory disease . These benefits may be mediated, in part, through improvements in cardiovascular function including improvements in cardiac autonomic nervous system balance (Laukkanen et al. 2019) and reductions in blood pressure (Brunt et al. 2016;Laukkanen et al. 2018b), arterial stiffness (Brunt et al. 2016;Laukkanen et al. 2018b), and intima-media thickness (Brunt et al. 2016); metabolic parameters, such as blood lipids (Pilch et al. 2010; Gryka et al. 2014) and glucose (Hooper 1999); and inflammation Hoekstra et al. 2018). Notably, there are marked differences in the effect of heat exposure on glycemic parameters depending on whether they are measured after acute or chronic exposure and if the heating intervention entails whole-body or partial-body heat exposure. ...
... Growing evidence demonstrates that whole-body heat therapy may reduce all-cause mortality (Laukkanen et al. 2015(Laukkanen et al. , 2018a, fatal cardiovascular disease (Laukkanen et al. 2015(Laukkanen et al. , 2018a, stroke (Kunutsor et al. 2018), dementia , and respiratory disease . These benefits may be mediated, in part, through improvements in cardiovascular function including improvements in cardiac autonomic nervous system balance (Laukkanen et al. 2019) and reductions in blood pressure (Brunt et al. 2016;Laukkanen et al. 2018b), arterial stiffness (Brunt et al. 2016;Laukkanen et al. 2018b), and intima-media thickness (Brunt et al. 2016); metabolic parameters, such as blood lipids (Pilch et al. 2010; Gryka et al. 2014) and glucose (Hooper 1999); and inflammation Hoekstra et al. 2018). Notably, there are marked differences in the effect of heat exposure on glycemic parameters depending on whether they are measured after acute or chronic exposure and if the heating intervention entails whole-body or partial-body heat exposure. ...
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... A study by Laukkanen et al. found that sauna bathing positively affects arterial stiffness, blood pressure, and some blood-based biomarkers for cardiovascular disease. 36 Sauna bathing has also been linked to improvement in pain from disorders like osteoarthritis. 37 However, individuals with SB should use caution, as autonomic dysfunction can impair heat regulation, and autonomic dysreflexia may cause dangerous spikes in blood pressure. ...
... In Korea, bathing has evolved through history from ritualistic and skincare practices to therapeutic uses, such as hot spring bathing, which emphasizes its health benefits [6] [7]. Recent studies have highlighted the positive effects of bathing on both physical and mental health, especially for those seeking stress relief and overall health improvement [8]. ...
... Sauna under the influence of high ambient temperature leads to the dilation of blood vessels and their relaxation, which leads to a decrease in blood pressure [10,11,12,13,14]. As a result, blood flow through the tissues increases, along with the nutrients and oxygen it contains. ...
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... Passive heat therapy, whereby individuals are exposed to acute bouts of heating for periods of ∼10-90 mins (Harwood et al. 2021;Pizzey et al. 2021), eliciting increases in heart rate and sweating, and a redistribution of blood from the core to the periphery (Laukkanen et al. 2018), is a nonpharmacological intervention that has been used for millennia for the treatment of a range of ailments and diseases (Papaioannou et al. 2016). More recently, passive heat therapy interventions have been utilised across a range of clinical (Akerman et al. 2019;Rodrigues et al. 2020) and rehabilitation settings (Brunt and Minson 2021) to promote physiological adaptations akin to those associated with exercise r Healthy persons with a mean age < 50 years. ...
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Background: there are no previous studies linking repeated heat exposure of sauna and the risk of memory diseases. We aimed to investigate whether frequency of sauna bathing is associated with risk of dementia and Alzheimer's disease. Setting: prospective population-based study. Methods: the frequency of sauna bathing was assessed at baseline in the Kuopio Ischaemic Heart Disease population-based prospective cohort study of 2,315 apparently healthy men aged 42-60 years at baseline, with baseline examinations conducted between 1984 and 1989. Hazard ratios (HRs) with 95% confidence intervals (CIs) for dementia and Alzheimer's disease were ascertained using Cox-regression modelling with adjustment for potential confounders. Results: during a median follow-up of 20.7 (interquartile range 18.1-22.6) years, a total of 204 and 123 diagnosed cases of dementia and Alzheimer's disease were respectively recorded. In analysis adjusted for age, alcohol consumption, body mass index, systolic blood pressure, smoking status, Type 2 diabetes, previous myocardial infarction, resting heart rate and serum low-density lipoprotein cholesterol, compared with men with only 1 sauna bathing session per week, the HR for dementia was 0.78 (95% CI: 0.57-1.06) for 2-3 sauna bathing sessions per week and 0.34 (95% CI: 0.16-0.71) for 4-7 sauna bathing sessions per week. The corresponding HRs for Alzheimer's disease were 0.80 (95% CI: 0.53-1.20) and 0.35 (95% CI: 0.14-0.90). Conclusion: in this male population, moderate to high frequency of sauna bathing was associated with lowered risks of dementia and Alzheimer's disease. Further studies are warranted to establish the potential mechanisms linking sauna bathing and memory diseases.
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Often I have advised a patient who was considering an unnecessary test, such as a coronary artery calcium test or carotid ultrasonography from a mobile van, to forgo that test and instead spend the money on something that he or she would actually enjoy, such as a massage or spa treatment. In this issue, Laukkanen et al¹ present data indicating that my advice would not only help my patients feel good but would also, if they chose to regularly use a sauna bath, help them live longer. Analyzing data from the Finnish Kuopio Ischemic Heart Disease Study, the authors found that men who took more frequent saunas (4-7 times per week) actually live longer than once-per-week users. Although we do not know why the men who took saunas more frequently had greater longevity (whether it is the time spent in the hot room, the relaxation time, the leisure of a life that allows for more relaxation time, or the camaraderie of the sauna), clearly time spent in the sauna is time well spent.
Article
Screening for atrial fibrillation (AF) by assessing the pulse is recommended in high risk patients. Some clinical trials demonstrated that the Microlife blood pressure monitor (BPM) with AF detection is more accurate than pulse palpation. This led to a change in practice guidelines in the UK where AF screening with the Microlife device is recommended instead of pulse palpation. Many BPMs have irregular heart beat detection (IHD) but they have not been shown to detect AF reliably. Recently, one study, in a highly select population, suggested that the Omron BPM with IHD has a higher sensitivity for AF than the Microlife BPM. We compared the Microlife and the Omron BPMs to ECG readings for AF detection in general cardiology patients. Inclusion criteria were age >50 without a pacemaker or defibrillator. A total of 199 subjects were enrolled, 30 with AF. Each subject had a 12-lead ECG, one Omron BPM reading and three Microlife BPM readings as per device instructions. The Omron device had a sensitivity of 30% (95% confidence interval (CI) 15.4%-49.1%) with the sensitivity for the first Microlife reading of 97% (95% CI 81.4%-100%) and the Microlife readings using the majority rule (AF positive if at least two out of three individual readings positive for AF) of 100% (95% CI 85.9%-100%). Specificity for the Omron device was 97% (95% CI 92.5%-99.2%) and for the first Microlife reading of 90% (95% CI 83.8%-94.2%%) and for the majority rule Microlife device 92% (95% CI 86.2%-95.7%) (p<.0001). The specificity of both devices is acceptable but only the Microlife BPM has a sensitivity value that is high enough to be used for AF screening in clinical practice.