Better treatment of stroke and higher education in later-born generations are the two main explanations for the decreasing prevalence of dementia among the oldest old, according to a new report from Swedish researchers – Between 1986 and 2008, the prevalence of dementia among 85-year-olds decreased from 30% to 22%, says Professor Ingmar Skoog, one of the researchers behind the study. The decrease was most accentuated for vascular dementia, a disorder…