Progression of Mild Cognitive Impairment to Dementia in Clinic- vs Community-Based Cohorts

Abstract

The term mild cognitive impairment (MCI) has been used to describe the transition between normal cognition and Alzheimer dementia.^1,2 Mild cognitive impairment is recognized as an important public health problem as a dementia risk. Annual conversion rates often range from 10% to 15% in clinic samples.^3-5 Conversion rates in community-based studies are often substantially lower (ie, 3.8%-6.3% per year^6-9). Mild cognitive impairment is also less stable in community samples.^8,10,11 Clearly patients with MCI compose a heterogeneous group, of whom not all rapidly convert to dementia. As such, it is important to identify risk factors for progressing rapidly among individuals diagnosed with MCI.