This systematic review and meta analysis of randomized, placebo-controlled, blinded trials summarized the evidence on selenium’s effect on thyroid autoantibody titers, requirement for LT₄ replacement therapy, ultrasonographic thyroid morphology, and mood in patients with HT under LT₄ treatment. The meta analysis included 4 studies. Patients with HT assigned to Se supplementation for 3 months demonstrated significantly lower thyroid peroxidase autoantibodies (TPOab) titers (four studies, random effects weighted mean difference: −271.09, 95% CI: −421.98 to −120.19, p< 10-⁴) overall and for selenomethionine 200mcg/d, but not sodium selenite; and a significantly higher chance of reporting an improvement in well-being and/or mood (three studies, random effects risk ratio: 2.79, 95% CI: 1.21-6.47, p= 0.016) when compared with controls. Demands in LT₄ replacement therapy and ultrasonographic thyroid morphology were found either unaltered or underreported. The evidence suggests a different pattern of response to Se supplementation in HT relative to baseline TPOab titers, with a larger response in those with higher antibody levels; if confirmed, this could be used to identify which patients would benefit most from treatment. Further study is required to demonstrate an improvement in thyroid function and morphology. (Thyroid. 2010 Oct;20(10):1163-73.) PMID: 20883174.
