Conceptual evolution in Alzheimer's disease: implications for understanding the clinical phenotype of progressive neurodegenerative disease.

Over the past several decades, our understanding of Alzheimer's disease (AD) has seen an evolution from the dichotomous concept of normal versus AD in the dementia state to a more accurate and complete appreciation of AD as a progressive disorder with clinical, biological, and pathological features occurring along a continuum from normal to end-stage disease. Integrating our understanding of the relationships and interplay between the clinical, biological, and pathological features of AD may allow the identification of AD at even preclinical, completely asymptomatic stages of the disease. This review attempts to summarize the clinical stages of AD in terms of epidemiology, historical evolution of disease stage diagnoses, cognitive/neuropsychologic features, psychiatric/behavioral manifestations, and functional decline in the context of our developing understanding of the biological processes responsible for the pathogenesis of AD described in detail in the accompanying articles.

Comparison of recruitment efforts targeted at primary care physicians versus the community at large for participation in Alzheimer disease clinical trials.

Inefficient and delayed recruitment into clinical trials in Alzheimer disease are major obstacles impeding progress in the discovery of more effective therapeutic strategies to combat this disease. Despite widespread recognition of this problem, limited empirical data demonstrating the effectiveness of specific recruitment strategies are available to guide recruitment endeavors. This study was designed to evaluate the effectiveness of recruitment efforts targeting either the primary care health professionals (PCPs) or patients and families with a community grass-roots outreach event.