Diagnostic issues in non-AD dementias

Abstract

Disease diagnosis would be a relatively easy task for clinicians if there were biologic markers for the disease in question. However, there are no established markers for the diagnosis of Alzheimer's disease (AD) or non-Alzheimer's disease (non-AD) dementias. Identifying specific markers has proven to be severely hindered by the lack of awareness of reliable and valid diagnostic criteria for these diseases. This chapter focuses on a review of current criteria used for diagnosing non-AD dementias and a critical evaluation of their accuracy (i.e. sensitivity, specificity, and positive predictive values) and inter-rater reliability. This review emphasizes the critical need for prospective, longitudinal clinicopathologic studies in order to facilitate a comprehensive revision of the current strategies and criteria used for the diagnosis of non-AD dementias. Such investigations will not only help the clinician in making accurate diagnoses early in the disease process, but also enable future studies to identify possible biologic markers for non-AD dementias. This in turn may allow research to focus on possible cures for these diseases rather than solely on symptomatic treatment.