100 study participants with mild-to-moderate AD who are scheduled to have elective noncardiac, nonneurologic, nonvascular surgery will be recruited at MGH. Surgeons will first introduce the study to patients at their preoperative surgical clinic visit. If a patient expresses interest in the study, and with permission of the surgeon, the patient will then be contacted by study staff at his/her PATA preoperative evaluation and medical optimization clinic visit. Recruitment, screening, and enrollment will then occur at the patient's PATA clinic visit.