Neuroanatomical signature of super‐ageing: Structural brain study of youthful episodic memory in people over the age of 80

Abstract

AbstractBackgroundSuperagers are people over the age of 80 that possess an episodic memory function of a person 20‐30 years younger. By drawing on a large (N=1213) longitudinal cohort of elderly individuals, we aimed to identify a superager subgroup and to determine key differences, including brain structure, between superagers and peers with normal episodic memory for their age.MethodA sample of 64 superagers (mean age 81.9 years, 59.4% women) and 19 age‐matched controls (mean age 82.6 years, 57.9% women) from the Vallecas Project cohort based at Fundación CIEN were selected according to their episodic memory score in the Free and Cued Selective Reminding Test; superagers scored at or above the mean value of a 50‐56yo person and controls scored within one standard deviation for their age. Demographic, genetic (APOE), lifestyle, clinical and neuropsychological variables were compared. Structural whole‐brain measures of grey matter volume are analised across groups at baseline and over time for up to 5 years (2‐6 time points) using CAT12 toolbox in SPM12.ResultThere were no differences in age, sex, years of education, current frequency of physical exercise or APOE genotype across groups. A history of anxiety, depression and cardiopathy was less frequent in superagers. At baseline, a higher grey matter volume in superagers compared to controls was shown in the bilateral anterior thalamus and regions within the temporal lobe including bilateral effects in the hippocampus, the amygdala, the entorhinal cortex, the parahippocampal gyrus and the fusiform gyrus (p < 0.05 FWE corrected). The longitudinal analysis revealed reduced grey matter volume loss over time in superagers in bilateral hippocampus, entorhinal cortex, parahippocampal gyrus, the left amygdala, bilateral basal forebrain, caudate, anterior insula, and right posterior cingulate (p < 0.05 FWE corrected).ConclusionBaseline differences between these two populations were located in a neuroanatomical network linked with memory function including key areas within the temporal lobe and also the anterior thalamus. The atrophy rate over time in these temporal regions is slower for the superager group, suggesting that they are more resistant than controls to the ageing decline of memory‐related areas.