Letters Section Editor: Robert M. Golub,
MD, Senior Editor.
In Reply: We appreciate Dr Palatini's elaboration
on a point that we raised in our article. Whereas we adjusted for several
established risk factors for AF,1 we acknowledged
in our discussion that we were unable to account for all AF risk factors,
including some known to have a genetic basis, such as C-reactive protein,2 hemostatic factors,3 left
atrial enlargement,4 Graves disease, alcohol
use,5 and echocardiographic features that
are associated with AF.4 Palatini et al6 have shown that left atrial size is heritable,
and call for a similar analysis to be undertaken in the Framingham study.
We concur that it would be informative to examine whether adjustment for left
atrial size in our regression models would diminish the estimated risk of
parental history for offspring AF; a diminished odds ratio might suggest that
the genetic component of AF is partially mediated through left atrial size.
Overall, we concur with Palatini that further research is necessary to understand
the mechanism(s) by which parental history of AF increases the risk of AF
Fox CS, Vasan RS, Benjamin EJ. Parental Atrial Fibrillation as a Risk Factor for Atrial Fibrillation in Offspring—Reply. JAMA. 2004;292(10):1174-1175. doi:10.1001/jama.292.10.1175-a