[1] Harvard TH Chan Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA
[2] Erasmus MC, Dept Epidemiol, Rotterdam, Netherlands
[3] Erasmus MC, Dept Neurol, Rotterdam, Netherlands
[4] Leiden Univ, Dept Gerontol & Geriatr, Med Ctr, Leiden, Netherlands
[5] Erasmus MC, Dept Radiol & Nucl Med, Rotterdam, Netherlands
[6] Northwestern Univ, Dept Neurol, Feinberg Sch Med, Chicago, IL 60611 USA