Don’t sweat it! A reflection on the benefits of sauna therapy in chronic disease

Paul McNamara (PM) is a GP in Glasgow and honorary clinical lecturer at the University of Glasgow. He is on X: @DocPaulMcNamara
Khalid Abdalla is a 5th year medical student at the University of Glasgow

Ten years ago, at the age of 30, I  (PM) found myself on the other side of the doctor-patient interaction. The transition from doctor to patient was difficult, to say the least. I was used to being in control and making the treatment plans. Then I became like any other patient; vulnerable, anxious, and well, if I’m really honest; absolutely petrified.

I had crippling back pain. I had to roll out of bed in the morning, wincing in pain with every movement. I lost 2 stone in weight in 6 weeks. I was having fevers and severe fatigue that made every step I took feel like I was wadding through treacle. Oh, and then there was the drenching night sweats.

was dying. I knew it. I was riddled with metastatic malignancy. What else could it be? I became the patients that I had read about when revising for exams and who presented in my clinics.

Thankfully, after numerous investigations, I wasn’t dying (not yet anyway); I was diagnosed with ankylosing spondylitis with severe systemic inflammation. I let the diagnosis drench and nourish me like a scorched meadow in desperate need of life giving water. I wasn’t well, but it wasn’t the untreatable metastatic monster I had manifested in my mind!

After trying multiple treatments, I was started on biological therapy and my symptoms ‘settled.’ However, the fatigue persisted and the pain and stiffness was relentless. I decided to try and implement the non-pharmacological methods I informed my patients about on a regular basis.

Physio, stretching and sauna therapy became an almost daily routine. I noticed significant benefits from sauna therapy. What was this simple, cheap and accessible ‘therapy’ doing to my physiology?

Hyperthermal therapy, via infrared saunas or other modalities has been used for centuries as a tool to improve general health and wellbeing. It has received significant recent academic attention, as it shows promise in improving musculoskeletal, metabolic and cardiovascular health.

Chronic musculoskeletal pain and stiffness caused by inflammatory conditions such as axial spondyloarthritis can have a significant impact on an individual’s quality of life. I can testify it’s no joke. Greater disease activity can impact individuals’ ability to work, exercise or maintain independence, in addition to the psychological implications of chronic disease. Sauna therapy is a promising adjunct in the non-pharmacological management of these conditions. Theoretically, this could provide patients with an easy, fast-acting and effective method to improve functionality and reduce symptoms.

A pilot study by Oosterveld et al demonstrated proof of concept. 17 patients with Rheumatoid Arthritis and 17 patients with ankylosing spondylitis were treated with twice weekly infrared sauna therapies over 4 weeks. This study demonstrated a statistically significant improvement in pain and stiffness during treatment sessions. Clinical improvements in pain, stiffness and fatigue were also observed after treatments.¹ Importantly, there was no evidence of adverse effects or exacerbation of disease activity.

These clinical improvements may correlate to immune molecular changes. A 2014 meta-analysis study investigated the immunological responses of whole-body hyperthermal treatment in patients with ankylosing spondylitis. Compared to placebo subjects, patients with ankylosing spondylitis exhibited an earlier and more pronounced increase of Interleukin-10 post treatment.² Interleukin-10 is a key anti-inflammatory cytokine, which exhibits its action by blocking cytokine production by immune cells. A 2023  meta-analysis reviewing the clinical and molecular effects of heat therapy in rheumatic and musculoskeletal diseases elaborated on this, demonstrating a decrease in TNF-alpha correlated with an up to 3 month improvement in pain associated with serial hyperthermia exposure.³ Another study demonstrated a statistically significant inverse correlation between sauna frequency and serum C-reactive protein concentrations.⁴

Sauna therapy has also been linked to improved cardiovascular health. Multiple studies between 2018 and 2022 by Lee et al. demonstrated statistically significant improvement in systolic and diastolic blood pressure in patients with at least one cardiovascular risk factor.⁵ These are seen both acutely, and longer term compounded improvements are also seen after 4 weeks of sauna therapy. A 2022 study by the same author showed that exercise regimes with post-exercise sauna therapy displayed greater improvements in cardio-respiratory function, reduced BP and reduced cholesterol levels compared to cohorts with the same exercise regimes but no post-exercise sauna.⁶ Laukkanen et al showed that frequent sauna use reduces the risk of fatal cardiovascular disease by 50%.⁷ This cardioprotective effect is attributed to increased production of nitrous oxide from the cardiac endothelial cells. This is supported by a study by Kihara et al, which demonstrated improved arterial dilatation and reduced serum BNP levels in patients with chronic heart failure treated with sauna therapy. Sauna therapy can be recommended in addition to exercise to improve cardiac health, or as a low-impact alternative to chronically ill individuals who wouldn’t tolerate traditional exercise regimes.⁸

A 2023 study demonstrated a decrease in both fasting glucose and cortisol compared after a 12 week sauna therapy regime.⁹ Further, a 2017 retrospective analysis has also linked increase sauna usage to a 65% lower incidence of Alzheimer disease.¹⁰ Repeat sauna usage was also linked with reduced total cholesterol, LDLC and increased levels of HDL.¹¹ Finally, sauna therapy has also been shown to promote better sleep quality,⁹ improve mood and support appetite,¹² making it a valid consideration as an adjunct to those affected by psychological manifestations of chronic disease.

There are some contraindications to Sauna use. These include unstable angina pectoris, recent myocardial infarction, and severe aortic stenosis.¹³

Personally, I have found regular sauna therapy to have been transformative. It is a simple, non-invasive and effective modality with a considerable and growing evidence base. Should we, as primary care physicians, be recommending it as an adjunct to promote chronic pain relief, psychological wellbeing and improved metabolic health to our patients? It’s a hot yes from me!

References:

1. Oosterveld FGJ, Rasker JJ, Floors M, Landkroon R, van Rennes B, Zwijnenberg J, et al. Infrared sauna in patients with rheumatoid arthritis and ankylosing spondylitis. Clinical Rheumatology. 2008 Aug 7;28(1):29–34.
2. Zauner D, Franz Quehenberger, Hermann J, Dejaco C, Stradner MH, Tatjana Stojakovic, et al. Whole body hyperthermia treatment increases interleukin 10 and toll-like receptor 4 expression in patients with ankylosing spondylitis: A pilot study. International Journal of Hyperthermia. 2014 Sep 1;30(6):393–401.
3. Klemm P, Schulz N, Boettger P, Lange U. Heat therapy in rheumatic and musculoskeletal diseases – an overview of clinical and molecular effects. International journal of hyperthermia. 2024 Mar 4;41(1).
4. Laukkanen JA, Laukkanen T. Sauna bathing and systemic inflammation. European Journal of Epidemiology [Internet]. 2017 Dec 5;33(3):351–3. Available from: https://link.springer.com/article/10.1007%2Fs10654-017-0335-y
5. Lee E, Willeit P, Tanjaniina Laukkanen, Kunutsor SK, Zaccardi F, Khan H, et al. Acute effects of exercise and sauna as a single intervention on arterial compliance. European Journal of Preventive Cardiology. 2019 Jun 8;27(10):1104–7.
6. Lee E, Kolunsarka I, Kostensalo J, Ahtiainen JP, Haapala EA, Willeit P, et al. Effects of regular sauna bathing in conjunction with exercise on cardiovascular function: a multi-arm, randomized controlled trial. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology. 2022 Sep 1;323(3):R289–99.
7. Laukkanen T, Kunutsor SK, Khan H, Willeit P, Zaccardi F, Laukkanen JA. Sauna bathing is associated with reduced cardiovascular mortality and improves risk prediction in men and women: a prospective cohort study. BMC Medicine [Internet]. 2018 Nov 29;16(1). Available from: https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-018-1198-0
8. Kihara T, Biro S, Imamura M, Yoshifuku S, Takasaki K, Ikeda Y, et al. Repeated sauna treatment improves vascular endothelial and cardiac function in patients with chronic heart failure. Journal of the American College of Cardiology. 2002 Mar;39(5):754–9.
9. Fatahi J, Baigzadeh M, Ghahramani M. The Effect of 12 Weeks of Dry and Steam Sauna on Fasting Glucose, Sleep Quality, and Cortisol Hormone in Middle-Aged Men. Journal of Nutrition,Fasting and Health [Internet]. 2023 Sep 1 [cited 2024 Feb 12];11(3):225–36. Available from: https://jnfh.mums.ac.ir/article_23335.html
10. Laukkanen T, Kunutsor S, Kauhanen J, Laukkanen JA. Sauna bathing is inversely associated with dementia and Alzheimer’s disease in middle-aged Finnish men. Age and ageing [Internet]. 2017;46(2):245–9. Available from: https://www.ncbi.nlm.nih.gov/pubmed/27932366
11. Pilch W, Szyguła Z, Klimek AT, Pałka T, Cisoń T, Pilch P, et al. Changes in the lipid profile of blood serum in women taking sauna baths of various duration. International Journal of Occupational Medicine and Environmental Health [Internet]. 2010 [cited 2023 Sep 19];23(2):167–74. Available from: https://pubmed.ncbi.nlm.nih.gov/20682487/
12. Masuda A, Nakazato M, Kihara T, Minagoe S, Tei C. Repeated Thermal Therapy Diminishes Appetite Loss and Subjective Complaints in Mildly Depressed Patients. Psychosomatic Medicine [Internet]. 2005 Jul;67(4):643–7. Available from: https://insights.ovid.com/crossref?an=00006842-200507000-00021
13. Hannuksela ML, Ellahham S. Benefits and risks of sauna bathing. Am J Med. 2001 Feb 1;110(2):118-26. doi: 10.1016/s0002-9343(00)00671-9. PMID: 11165553.

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