Efforts to find treatments for AD have yielded only modest benefits, likely because longstanding AD pathological processes induce irreversible neurological compromise. These processes begin years before the onset of clinical symptoms. This possibility has been incorporated into a model describing stages of AD development, articulated by the NIA/Alzheimer's Association preclinical workgroup of which the Co-Director of the Kulynych Alzheimer's Research Center, Dr. Suzanne Craft, was a member. According to this model, the best hope for countermanding the effects of AD lies in intervening at the earliest possible point in the pathological cascade. There are several important ongoing efforts in adults with preclinical AD that directly target amyloid aggregation. Although this strategy addresses an important aspect of the AD pathological cascade, we believe that addressing metabolic dysfunction affecting glucose and insulin regulation offers a complementary approach, in that it may reduce amyloid burden and toxicity, while also directly enhancing synaptic health, brain metabolism, tau regulation and neurovascular function. The purpose of the ADCC is to identify and characterize early risk factors that predict cognitive decline and dementia in asymptomatic adults and adults with early signs of cognitive impairment. The data obtained from this study, collected at enrollment and follow-up will allow us to examine disease trajectory in individuals with and without prediabetes and other measures of glucoregulatory dysfunction in this process. The enrollees, who will be well-characterized with regard to cognitive and metabolic status through ADCC assessments, will provide an important resource for other local (institution) and national investigations. Data collected from participants enrolled in the ADCC will be stored indefinitely for future investigations.