A systematic review of type 2 diabetes mellitus and hypertension in imaging studies of cognitive aging: time to establish new norms

摘要: The rising prevalence of type 2 diabetes (T2DM) and hypertension in older adults, the deleterious effect these conditions on cerebrovascular brain health, is creating a growing discrepancy between "typical" cognitive aging trajectory "healthy" trajectory. These changing health demographics make T2DM important topics study their own right, warrant attention from perspective neuroimaging research. Specifically, interpretation individual or group differences blood oxygenation level dependent magnetic resonance imaging (BOLD MRI) positron emission tomography (PET H2O15) signals as reflective neural activation underlying operation interest requires assumptions intact vascular amongst participants. Without adequate screening, inclusion individuals with samples may introduce unwanted variability bias to and/or measures, increase potential for error. We conducted systematic review literature document extent which researchers account conditions. Of 232 studies selected review, few explicitly excluded (9%) (13%). A large portion had exclusion criteria that made it difficult determine whether were (44% 37%), many did not mention any selection related (34% 22%). all surveyed studies, only 29% acknowledged addressed influence intersubject measured BOLD PET signals. To reinforce notion should be overlooked source bias, we also provide an overview metabolic changes associated hypertension, they relate health.