This study will enroll people who have participated in the second GENOA exam and who live in Jackson, Mississippi. Participants will attend one study visit at the University of Mississippi Medical Center. During the study visit, participants will be interviewed by study staff about their medical and family health history; health behaviors; physical activity levels; and use of tobacco, alcohol, and medications. They will complete a walking activity and tasks to assess memory, thinking speed, and accuracy. Participants will also complete a questionnaire about their mood, a physical examination, a CT scan of the heart, and a blood collection. A portion of blood will be stored for future research studies.