Lead author Francine Grodstein, ScD, Rush Alzheimer's Disease Center, Chicago, Illinois, explained that resilience to Alzheimer's pathology is characterized by individuals having no clinical symptoms of dementia despite having significant pathology that would be expected to be associated with such symptoms.
"Reductions in cerebrovascular pathology are very encouraging and show that we really need to continue to emphasize public health and medical efforts to reduce stroke and stroke risk factors, such as diabetes, obesity, and hypertension," Grodstein stated. In the study, the authors explain that in recent years, several studies have indicated the incidence of dementia in the US may be declining, but data are not entirely consistent.
Grodstein explained that the researchers used data from unique cohorts of individuals who had agreed to be followed throughout their life and also post-mortem, giving unique data on brain pathology over time. In contrast, cerebral atherosclerosis and arteriosclerosis were dramatically lower over time; for example, age-standardized prevalence of moderate to severe atherosclerosis ranged from 54% among those born from 1905-1914 to 22% for 1925-1930.
"For example, enhanced resilience to neuropathology over time is plausible. Indeed, several cohorts have reported that controlling for education, a marker of cognitive resilience, attenuates apparent time trends in dementia incidence, providing evidence that changes in cognitive resilience may be an effective path to reducing dementia," they note.