Free triiodothyronine/free thyroxine ratio rather than thyrotropin is more associated with metabolic parameters in healthy euthyroid adult subjects

Abstract

Thyrotropin levels were positively associated with FT3/FT4 ratio within the euthyroid range. The higher FT3/FT4 ratio is associated with increased risk of metabolic syndrome parameters and insulin resistance. FT3/FT4 ratio has a better predictive power for metabolic syndrome than TSH.