ONLINE FIRST Impact of Smoking on Cognitive Decline in Early Old Age The Whitehall II Cohort Study Séverine Sabia, PhD; Alexis Elbaz, MD, PhD; Aline Dugravot, MSc; Jenny Head, MSc; Martin Shipley, MSc; Gareth Hagger-Johnson, PhD; Mika Kivimaki, PhD; Archana Singh-Manoux, PhD Arch Gen Psychiatry. Published online February 6, 2012. doi:10.1001/archgenpsychiatry.2011.2016 http://archpsyc.ama-assn.org