Regional Differences in Diagnostic Conversion to Dementia

The worldwide increase in dementia incidence has important health and environmental implications for both patients and caregivers. The ability to predict who will develop dementia and to identify risk factors of rapid progression would be a major advance in preventative healthcare. Few studies have surveyed the impact of environmental differences in combination with clinical and genetic factors in modifying dementia progression. We examined variation in diagnostic conversion from normal cognition to dementia in a multi-site cohort of study volunteers. Center-to-Center differences, residence in sparsely populated regions, lower education, older age and more severe cognitive impairment at study entry were associated with conversion to dementia within 5 years following the baseline visit. Because of strong individual Center effects, for which the underlying determinants were not identified, studying diagnostic conversion on a Center-by-Center basis may reveal viable genetic and environmental influences.