Kyushu University sheds light on the relationship between hot springs and hypertension in older people - possible prevention of hypertension through habitual use at night

The proportion of people with hypertension is rising around the world - in Japan, over 60% of men aged 50 and over and women aged 60 and over have hypertension. Currently, hypertension is the main reason for hospital visits, and as the medical treatment period is long, it creates a large burden on medical finances. On top of this, hypertension is a risk factor for serious illness as a result of COVID-19. It has long been thought that hot spring bathing has the effect of suppressing hypertension, but the details of the relationship between hot spring use and hypertension were unclear.

Professor Takahiko Horiuchi, Associate Professor Toyoki Maeda, Lecturer Satoshi Yamasaki and Lecturer Tomotake Tokunou of the Department of Internal Medicine, Kyushu University Beppu Hospital and their colleagues carried out a survey of over 10,000 people aged 65 and over living in Beppu City, Oita Prefecture and found that minimal occurrence of hypertension in the past is linked to the use of hot springs. It is hoped that the effective use of hot springs could help prevent the onset of hypertension in older people. Their outcomes were published in Scientific Reports.

In 2011, the research group carried out a survey of over 10,000 people aged 65 and over living in Beppu City, Oita Prefecture, focusing on their use of hot springs and their medical history. When the group carried out logistic regression analysis, they found that being 85 or over and/or having a medical history of arrhythmia, stroke, gout, diabetes, dyslipidemia or renal impairment were risk factors for the onset of hypertension, while the use of hot springs at night and a history of chronic hepatitis were associated with minimal hypertension.

It is possible that habitual hot spring bathing at night is associated with preventing the onset of hypertension in older people because it leads to improvements in sleep disorders caused by chronic stress. In the future, researchers must carry out systematic randomized comparisons to prove this hypothesis. The details of these survey results are to be announced on May 12, 2023 at the 88th Annual Meeting of the Japanese Society of Balneology, Climatology and Physical Medicine.

Journal Information
Publication: Scientific Reports
Title: Hot spring bathing is associated with a lower prevalence of hypertension among Japanese older adults: a cross-sectional study in Beppu
DOI: 10.1038/s41598-022-24062-3