Frequent sauna bathing may reduce the risk of pneumonia in middle-aged Caucasian men: The KIHD prospective cohort study

Objective Emerging evidence suggests sauna bathing to be linked with numerous health benefits. Having frequent sauna baths has been found to be associated with reduced risk of acute and chronic disease conditions. Sauna bathing may reduce the risk of respiratory diseases; however, the evidence is uncertain. We aimed to assess the association of frequency of sauna bathing with risk of pneumonia. Methods Baseline sauna bathing habits were assessed by administration of questionnaires in a prospective cohort of 2210 men aged 42–61 years. Results During a median follow-up of 25.6 years, 375 hospital diagnosed cases of pneumonia were recorded. In age-adjusted analyses, the hazard ratios (HRs) 95% confidence intervals (CIs) of pneumonia were 0.67 (0.53–0.83) and 0.53 (0.34–0.84) for participants who had 2-3 and ≥4 sauna sessions per week respectively compared with participants who had ≤ 1 sauna session per week. After further adjustment for several major risk factors, the HRs were 0.69 (0.55–0.86) and 0.56 (0.35–0.88) respectively. The associations remained on additional adjustment for total energy intake, socioeconomic status, physical activity, and C-reactive protein, 0.72 (0.57–0.90) and 0.63 (0.39–1.00) respectively. Conclusions Frequent sauna baths is associated with reduced pneumonia risk in a middle-aged male Caucasian population.