Introduction

Alzheimer's Disease (AD), the most common disease manifesting as memory loss and dementia in the elderly, affects more than 4 million elderly individuals in the United States (Brookmeyer et al., 1998; Mayeux, 2003; Cummings, 2004). Due to increased life expectancy and the baby boom, the elderly are the most rapidly growing segment of our society. Thus, over the next several decades, the number of persons with AD in the United States will triple. Because of its prevalence, costs, lack of mechanismbased treatments, and impact on individuals and caregivers, AD is one of the most challenging diseases in medicine (Price et al., 1998; Wong et al., 2002; Citron, 2004; Walsh and Selkoe, 2004). The development of effective new therapies will have a significant impact on the health and care of the elderly. This review focuses on important research relevant to AD, including: the diagnosis of clinical syndrome; value of laboratory studies, particularly new imaging efforts; advances in genetics and neuropathology/biochemistry; knowledge of pathogenesis; and development of experimental models of value for understanding disease mechanisms and for developing experimental therapeutics.

The classical clinical syndrome of AD (i.e. progressive memory loss, altered cognition, and dementia) (Cummings, 2004) results from abnormalities associated with dysfunction and death of specific populations of neurons in neural systems involved in memory and cognition (Price et al., 1998). A variety of laboratory approaches and imaging methods are useful for diagnosis, for predicting the clinical course and for assessing outcomes of therapy.