Houston, Texas, USA : Regular sauna use is associated with a lower risk of death from cardiovascular disease (CVD) in men and women aged 50 years and over, according to a study published in the open access journal BMC Medicine.
Researchers from the University of Eastern Finland and the University of Jyväskylä, Finland found that mortality from CVD among people who used a sauna four to seven times a week was 2.7 fatal CVD events per 1,000 person years, compared to 10.1 events per 1,000 person years in those who used a sauna once a week. Person years refers to the total number of years that participants remained in the study. It is a way of measuring the number of new events in the study population in a given time period, with a lower number of events indicating a lower risk.
Professor Jari Laukkanen, the corresponding author, said: “An important finding of this research is that more regular sauna use is associated with a lower risk of death from CVD in middle-aged to elderly women as well as in men. Previous population studies were done mostly in men only.”
Professor Laukkanen continued: “There are several possible reasons why sauna use may decrease the risk of death due to CVD. Our research team has shown in previous studies that high sauna use is associated with lower blood pressure. Additionally, sauna use is known to trigger an increase in heart rate equal to that seen in low to moderate intensity physical exercise.”
The incidence (i.e. number of new cases) of CVD mortality over the study period was also found to decrease as the length of time spent in the sauna per week increased. For those who spent over 45 minutes per week in the sauna in total the incidence was 5.1 per 1,000 person years whilst it was 9.6 for those who spent less than 15 minutes per week in the sauna in total.
The authors assessed sauna use by a self-reported questionnaire and checked deaths from cardiovascular causes against documents from hospitals and health centre wards, death certificates, as well as medico legal reports for 1,688 participants living in and around Kuopio, Finland. At the start of the study, the participants were on average 63 years old and 51.4% were women. Data for this prospective study were collected between 1998 and 2015 and the mean follow-up time was 15 years.
The authors caution that all the patients whose data were analyzed in this study were from one region and therefore there is a need for further research to understand if the findings apply to other populations. The observational nature of the study does not allow for conclusions about cause and effect.
Citation : Tanjaniina Laukkanen et al, Sauna bathing is associated with reduced cardiovascular mortality and improves risk prediction in men and women: a prospective cohort study, BMC Medicine (2018). DOI: 10.1186/s12916-018-1198-0
A second study found sauna use to be associated with reduced risk of cardiac and all-cause mortality.
Sauna use associated with reduced risk of cardiac, all-cause mortality
A sauna may do more than just make you sweat. A new study suggests men who engaged in frequent sauna use had reduced risks of fatal cardiovascular events and all-cause mortality, according to an article published by JAMA Internal Medicine.
Although some studies have found sauna bathing to be associated with better cardiovascular and circulatory function, the association between regular sauna bathing and risk of sudden cardiac death (SCD) and fatal cardiovascular diseases (CVD) is not known.
Jari A. Laukkanen, M.D., Ph.D., of the University of Eastern Finland, Kuopio, and coauthors investigated the association between sauna bathing and the risk of SCD, fatal coronary heart disease (CHD), fatal CVD and all-cause mortality in a group of 2,315 middle-aged men (42 to 60 years old) from eastern Finland.
Results show that during a median (midpoint) follow-up of nearly 21 years, there were 190 SCDs, 281 fatal CHDs, 407 fatal CVDs and 929 deaths from all causes. Compared with men who reported one sauna bathing session per week, the risk of SCD was 22 percent lower for 2 to 3 sauna bathing sessions per week and 63 percent lower for 4 to 7 sauna sessions per week. The risk of fatal CHD events was 23 percent lower for 2 to 3 bathing sessions per week and 48 percent lower for 4 to 7 sauna sessions per week compared to once a week. CVD death also was 27 percent lower for men who took saunas 2 to 3 times a week and 50 percent lower for men who were in the sauna 4 to 7 times a week compared with men who indulged just once per week. For all-cause mortality, sauna bathing 2 to 3 times per week was associated with a 24 percent lower risk and 4 to 7 times per week with a 40 percent reduction in risk compared to only one sauna session per week.
The amount of time spent in the sauna seemed to matter too. Compared with men who spent less than 11 minutes in the sauna, the risk of SCD was 7 percent lower for sauna sessions of 11 to 19 minutes and 52 percent less for sessions lasting more than 19 minutes. Similar associations were seen for fatal CHDs and fatal CVDs but not for all-cause mortality events.
“Further studies are warranted to establish the potential mechanism that links sauna bathing and cardiovascular health,” the study concludes.