Here is yet another systmatic analysis on lots of patients. It shows that FT4 high in the reference range but not TSH is correlated with increased chance of AF. It contradicts other studies showing the opposite. Here is a beautiful example of false findings from the result of a statistical anomaly called Simpson's amalgamation paradox. First no FT3 was done, so we have no knowledge as to whether this was a factor or not. Secondly we do not know if the people with higher FT4 were all in their comfort zones and thirdly this underlines what we wrote in our latest paper about the danger of lumping everyone into a big study regardless of their individual physiology, without previous stratification to study relevant subgroups.
Higher Serum FT4 Level Within the Reference Range, but Not Serum TSH, Is Associated With the Development of Atrial Fibrillation
Leung Angela M.. Clinical Thyroidology. December 2017, 29(12): 454-456. doi.org/10.1089/ct.2017;29....