Effect of a clinical stroke on the risk of dementia in a prospective cohort.

Gamaldo et al. reported the results of the Baltimore Longitudinal Study on Aging (BLSA), a prospective community-based study in which clinically overt stroke conferred an increased risk of dementia compared to subjects without stroke. The majority of patients who became demented after a stroke had evidence of mild cognitive impairment (MCI) preceding the stroke. Moreover, a clinically symptomatic stroke was a major risk factor for the progression of MCI to dementia. The authors discussed these results as consistent with the findings of the Italian Longitudinal Study on Aging (ILSA). In this study, the rate of progression to overt dementia in subjects with MCI was not 100%. This suggests that MCI is a heterogenous condition with a substantial number …