Sauna bathing is associated with reduced cardiovascular mortality and improves risk prediction in men and women: a prospective cohort study

Table 3 Hazard ratios of cardiovascular mortality according to the weekly duration of sauna bathing, overall and among men and women

Duration of sauna bathing (minutes/week)	Events/total	Model 1		Model 2		Model 3		Model 4*
Duration of sauna bathing (minutes/week)	Events/total	HR (95% CI)	P value	HR (95% CI)	P value	HR (95% CI)	P value	HR (95% CI)	P value
Overall
≤ 15	62/463	Ref		Ref		Ref		Ref
16–45	96/906	0.69 (0.50 to 0.96)	0.027	0.77 (0.55 to 1.06)	0.112	0.77 (0.55 to 1.07)	0.123	0.74 (0.51 to 1.09)	0.132
> 45	23/319	0.49 (0.30 to 0.80)	0.004	0.57 (0.35 to 0.93)	0.025	0.57 (0.35 to 0.94)	0.028	0.60 (0.34 to 1.05)	0.074
Men
≤ 15	29/157	Ref		Ref		Ref		Ref
16–45	72/461	0.83 (0.54 to 1.28)	0.406	0.92 (0.59 to 1.43)	0.711	0.92 (0.59 to 1.43)	0.705	1.05 (0.61 to 1.83)	0.846
> 45	17/203	0.50 (0.27 to 0.91)	0.023	0.57 (0.31 to 1.04)	0.068	0.57 (0.31 to 1.05)	0.073	0.68 (0.33 to 1.43)	0.311
Women
≤ 15	33/306	Ref		Ref		Ref		Ref
16–45	24/445	0.53 (0.31 to 0.89)	0.017	0.62 (0.36 to 1.08)	0.093	0.61 (0.35 to 1.07)	0.084	0.51 (0.28 to 0.91)	0.024
> 45	6/116	0.58 (0.24 to 1.39)	0.222	0.75 (0.31 to 1.83)	0.528	0.75 (0.31 to 1.85)	0.532	0.66 (0.25 to 1.76)	0.408

Model 1: adjusted for age and gender
Model 2: model 1 plus body mass index, smoking, systolic blood pressure, serum low-density lipoprotein cholesterol, alcohol consumption, previous myocardial infarction, and type 2 diabetes
Model 3: model 2 plus physical activity (duration per week) and socio-economic status
Model 4: model 3 plus incident coronary heart disease as a time-dependent covariate
CI confidence interval, HR hazard ratio; analysis is based on 1688 participants and 181 cardiovascular deaths
*The model was limited to the population at risk and did not include those who already had coronary heart disease

ISSN: 1741-7015