Table 2.

Brain glucose hypometabolism in persons at risk of AD but in whom cognitive performance is normal.

	Mean age (y)	Brain region	Brain glucose hypometabolism (% difference from control)	Reference
Insulin resistant young women with PCOS	25	Frontal cortex	-9 to -14	Castellano et al., 2015a
		Middle temporal cortex
Young adult carriers of Presenilin-1	30	Posterior cingulate	-14 to -25	Scholl et al., 2011
		Parietal cortex
		Temporal cortex
Young adult carriers of Apolipoprotein-E4	31	Parietal cortex	-9 to -11	Reiman et al., 2004
		Temporal cortex
		Posterior cingulate
		Prefrontal cortex
Maternal family history of AD	43	Parietal cortex	-12 to -21	Mosconi et al., 2006
		Temporal cortex
		Hippocampus
		Entorhinal cortex
		Posterior cingulate
Cognitively healthy older adults	72	Frontal cortex	-10 to -18	Nugent et al., 2016
		Temporal cortex
		Anterior cingulate
		Putamen
		Thalamus
Pre-diabetic older persons	74	Temporal cortex	N/A	Baker et al., 2011
		Parietal cortex
		Posterior cingulate
		Precuneus
		Prefrontal cortex

N/A, not available.