Table 1

Studies supporting use of FIRSs

STUDYNDURATIONLEVEL OF EVIDENCEINDICATIONPRIMARY OUTCOMESCOMMENTS
Kihara et al,3 20043014 dICHFFewer PVCs and lowered BNP levelsInfrared sauna treatment improves ventricular arrhythmias in patients with CHF
Kihara et al,4 20023014 dICHFClinical symptoms improved and BNP levels decreased; endothelial function improvedClinical improvement in CHF seen after FIRS therapy might be owing to improved endothelial function
Miyamoto et al,5 20051528 dIICHFCHF symptoms, ejection fraction, and walking distance improved; catecholamine levels decreasedInfrared sauna therapy is a safe and effective treatment of CHF
Sugahara et al,6 20031228 dIIPediatric CHF due to VSDClinical signs and symptoms of CHF decreased, urine nitrate levels decreased, and 75% of patients avoided surgical repairInfrared sauna therapy is safe and might be helpful in treating pediatric CHF; VSDs have a high incidence of spontaneous improvement
Masuda et al,7 20042814 dIPrevention of atherosclerosis by decreasing oxidative stressSystolic BP decreased, as did serum PGF2αInfrared sauna therapy might be cardioprotective
Imamura et al,8 20013514 dIIImpaired endothelial function in those with coronary risk factorsEndothelium-dependent vasodilatation improved; BP and fasting glucose levels decreasedInfrared sauna therapy is safe and improves vascular endothelial function
Biro et al,9 20031014 dIIObesityDespite weight loss, plasma ghrelin and leptin levels did not changeInfrared sauna therapy might blunt neurohormonal effects of weight loss due to calorie restriction
Masuda et al,10 20054628 dIChronic painIncreased likelihood of return to work; trend toward decreased pain and angerInfrared sauna therapy might be promising for the treatment of chronic pain
Masuda et al,11 2005235 dII*Chronic fatigue syndromeFatigue, pain, sleep, and low- grade fever improvedInfrared sauna treatment might be helpful for chronic fatigue syndrome

  • BNP—brain natriuretic peptide, BP—blood pressure, CHF—congestive heart failure, FIRS—far-infrared sauna, PGF2α—prostaglandin F2α, PVC—premature ventricular contraction, VSD— ventricular septal defect.

  • ↵* Although this study represents level II evidence, it is very weak owing to small sample size.