Genetic Thyrotropin Regulation of Atrial Fibrillation Risk Is Mediated Through an Effect on Height.

Context: A genetic predisposition to lower thyrotropin (TSH) levels is associated with increased atrial fibrillation (AF) risk through undefined mechanisms.

Objective: Defining the genetic mediating mechanisms could lead to improved targeted therapies to mitigate AF risk.

Methods: We used 2-sample mendelian randomization (MR) to test associations between TSH-associated single-nucleotide variations and 16 candidate mediators.