Department of Dietetics and Nutrition, University of Kansas Medical Center, Kansas City, KS, USA. Electronic address: scarlson@kumc.edu. Department of Biostatistics, University of Kansas Medical Center, Kansas City, KS, USA. Department of Dietetics and Nutrition, University of Kansas Medical Center, Kansas City, KS, USA. Schiefelbusch Institute for Life Span Studies/Department of Psychology, University of Kansas, Lawrence, KS, USA. Department Neurology, University of Kansas Medical Center, Kansas City, KS, USA.