Table 2. Proportional hazard regression analysis of cardiovascular mortality in the study population with a basal selenium level < 65 μg/L (mean value) during an intervention time of four years.

Variable	Hazard ratio	95% CI	P-value
Male	1.17	0.67–2.04	0.57
Smoking	1.84	0.96–3.52	0.07
IHD	1.02	0.59–1.77	0.94
EF<40%	2.23	1.15–4.30	0.02
Active treatment	0.50	0.26–0.95	0.03

Notes: CI: Confidence interval; COPD; EF: Ejection fraction. EF as obtained by echocardiography; IHD: Ischemic heart disease.