Effects of Age and Sex on Subcortical Volumes

Abstract

PurposeIn an increasingly aging society, it is of great importance to consider trajectories of subcortical volumes at different ages for understanding biological markers of aging. Thus, we investigated sex, age, and their interactions on subcortical volumes, including the basal ganglia (caudate, putamen, accumbens, and pallidum), thalamus, hippocampus, and amygdala.MethodsWe analyzed the adult lifespan trajectory of subcortical volumes and asymmetries in 563 healthy subjects aged from 19 to 86 using magnetic resonance imaging (MRI) data from the publicly available 7IXI data set.ResultsThe sex made strong contributions to the trajectories of subcortical volumes with aging, including the right putamen, right pallidum, bilateral thalamus, hippocampus, and amygdala. The volume of the right putamen, right pallidum, and right thalamus decreased more rapidly in males than in females, and the volume of the left thalamus, bilateral hippocampus, and amygdala in males followed a quadratic model, while those in females followed a linear decline model. The asymmetries in the caudate and hippocampus showed a linear decline, and a sex and age interaction was found in the hippocampus; that is, the asymmetry in the hippocampus decreased only in the males and not in the females. Changes in the accumbens and pallidum fit quadratic trajectories, in which females increased until 39.26 years old in the accumbens asymmetry and then began to rapidly decline, and males showed a linear decline. The asymmetry in the pallidum in males and females showed a slow decreasing period until almost 45 years of age and then increased.ConclusionThe results suggest that compared with females, males have a faster decline in the volume of the right putamen, right pallidum, and right thalamus, while aging occurred later but also faster in the left thalamus, bilateral hippocampus, and amygdala. Interestingly, we found the inflection point in the thalamus, bilateral hippocampus, and amygdala volume in the quadratic model, and after this point, the volume change accelerated with aging, which may have resulted from the stronger work pressure in the middle-aged men and the low levels of testosterone in the older adults. The interaction of age and sex on individual subcortical structures provides evidence to support the impact of sex on psychopathologies associated with degenerative brain disorders in the elderly. The findings may be significant to investigate the occurrence and prevalence of degenerative brain disorders in males and females. Future studies can focus on the functional and behavioral relations with subcortical structures for preventive measures of related disorders.

Whole Brain and Cranial Size Adjustments in Volumetric Brain Analyses of Sex- and Age-Related Trends

“…After such adjustment, this region becomes statistically insignificant (Table 4, Figure 6). However, there are contradictory reports for this structureno significant sex-related difference was found by Ritchie et al (2018), while Yanpei Wang et al observed more rapid decrease of the volume of right thalamus in the males than in the females (Wang et al, 2019).…”

“…Moreover, the standardized regression coefficients (β) and the significance of the regressor effects (p-values) were calculated to characterize age-related dimorphism and in the subsequent models, to adjust the TBV and ICV factors in this description. The p-values less than 0.05-a predetermined significance level-were accepted as indicating that the observed result would be highly unlikely under the null hypothesis (Király et al, 2016;Wang et al, 2019).…”

“…To optimally balance between Type I and Type II error, we took the correlation between the dependent variables (the volumes of the seventeen structures) into account by using the Simple Interactive Statistical Analysis Bonferroni tool. Using a Bonferroni correction that treats the variables as independent (proper Bonferroni: alpha/number of tests) would lead to a too stringent correction, as the dependent variables are not obtained in independent sub-groups (Wang et al, 2019). The subcortical volumes showed a mean correlation coefficient of r = 0.565, leading to an equivalent corrected alpha of 0.0146.…”

The Long-Term Outcome of Treatment for Graves' Hyperthyroidism

“…[111][112][113][114][115][116] Although the question whether there is significant adult neurogenesis remains a matter of controversy, 117 this specific region of the brain has been suggested as having an annual turnover of neurons of almost 2%. 118 Hippocampal gray matter volume alterations have been demonstrated in connection with normal physiological variability like exercise, 119 the menstrual cycle, 120 and aging 121 as well as in pathological conditions like Alzheimer's disease, 122 mild cognitive impairment, 123 post-traumatic stress disorder, 124 major depressive disorder, 125 126 Parkinson's disease, 127 and Cushing's syndrome, [112][113][114][115][116] all of which are illnesses with mental symptoms. These wideranging results are not easy to interpret.…”

Brain/MINDS Beyond Human Brain MRI Project: A Protocol for Multi-Site Harmonization across Brain Disorders Throughout the Lifespan

“…Such non-specificity may be at least partly addressed by investigating diseases across the lifespan, since some of brain changes reported in psychiatric disorders also occur in aging or development in healthy subjects, e.g. volumetric changes in subcortical structures in schizophrenia (Okada et al, 2016; and in healthy aging (O'Shea et al, 2016;Wang et al, 2019). We initially coordinated with 13 sites to explore various psychiatric and neurological disorders throughout the lifespan and to make use of a powerful harmonization method.…”