Blood pressure and blood selenium: a cross-sectional and longitudinal population study.

Abstract

Western Europeans have low blood levels of selenium (BSe), an antioxidant trace element. In a Flemish population, we investigated the cross-sectional and longitudinal association of blood pressure (BP) with BSe. We randomly recruited 710 subjects (mean age 48.8 years; 51.8% women). We measured BP and BSe and kept participants in follow-up for BP. At baseline, systolic/diastolic BP averaged (SD) 130/77 (17.3/9.2) mmHg. BSe was 97.0 (19.0) microg/L. Of 385 participants with normal baseline BP (<130 and <85 mmHg), over 5.2 years (range 3.4-8.4 years), 139 developed high-normal BP (130-139/85-90 mmHg) or hypertension (>or=140/90 mmHg). In multivariate-adjusted cross-sectional analyses of men, a 20 microg/L ( approximately 1 SD) higher BSe was associated with lower BP with effect sizes of 2.2 mmHg systolic (95% CI -0.57 to -5.05; P = 0.009) and 1.5 mmHg diastolic (95% CI -0.56 to -2.44; P = 0.017). In prospective analyses of men, a 20 microg/L higher baseline BSe was associated with a 37% (95% CI -52 to -17; P = 0.001) lower risk of developing high-normal BP or hypertension. None of these associations was significant in women. Deficiency of selenium might be an underestimated risk factor for the development of high BP in European men.