Serum selenium is low in newly diagnosed Graves’ disease: a population‐based study

Abstract

Selenium deficiency may play an important role in the initiation and progression of autoimmune thyroid disease. To compare serum selenium (s-Se) values in patients with newly diagnosed autoimmune thyroid disease and controls from the Danish population. S-Se was measured in triplicate by a fluorimetric method. Patients with newly diagnosed Graves' disease (GD) (n=97) or autoimmune overt hypothyroidism (AIH) (n=96), euthyroid subjects with high serum levels of thyroid peroxidase antibody (TPO-Ab) (TPO-Ab >1500U/ml, n=92) and random controls (n=830). Differences in s-Se values. S-Se was lower in patients with GD than in controls (mean (SD), GD: 89·9μg/l (18·4); controls: 98·8μg/l (19·7), P<0·01). This was confirmed in a multivariate logistic regression model adjusting for age, sex, mineral supplements, smoking, geographical region and time of sampling (P<0·01). In a linear model, s-Se was similar in patients with AIH (mean (SD): 98·4μg/l (24·9)) and in controls (P=0·86). In the multivariate model however, s-Se was marginally lower in patients with AIH compared to controls (P=0·04). There was no significant difference in s-Se between euthyroid participants with high TPO-Ab and random controls (linear: P=0·97; multivariate: P=0·27). Patients with newly diagnosed GD and AIH had significantly lower s-Se compared with random controls. Our observation supports the postulated link between inadequate selenium supply and overt autoimmune thyroid disease, especially GD.