Low plasma selenium as a risk factor for cancer death in middle‐aged men

Abstract

In a population study, 10,000 men (aged 46–48 years) were invited to a health screening program. At follow‐up, which was up to eight years later, 61 subjects had died from cancer; from 35 of these subjects, plasma samples were available that were obtained at the initial screening. These samples, together with samples from two living controls for each case, were analyzed for selenium, retinol, cholesterol, triglyceride, and a number of plasma proteins. Plasma selenium was significantly lower (p < 0.05) in cases than in controls (means: 1.06 vs. 1.12 μmol/l). The proportion of cases increased significantly from the highest to the lowest quintile of plasma selenium, and the relative risk for cancer death was 3.8 times higher in the lowest quintile compared with the highest. Mean plasma retinol was similar in cases (2.53 μmol/l) and controls (2.56 μmol/l). Cases and controls also had similar values for plasma cholesterol, triglyceride, uric acid, apolipoprotein B, orosomucoid, prealbumin, retinol‐binding protein, and β₂‐microglobulin. Apolipoprotein AI in plasma was lower among cases (p < 0.025). Cases smoked significantly more than controls did (p < 0.05). Data indicate that low plasma selenium was a risk factor for cancer death in middle‐aged men who lived in the same area. Further studies are necessary to establish whether differences in selenium intake, selenium metabolism, or other factors related to selenium are responsible for the relations observed. At present, the available data do not justify selenium supplementation programs in the whole population.