◇発表者◇
　劉　蛍旭
　人間・社会領域
　博士研究教育院生2年
　医学系研究科　医科学専攻

◇学会名称◇
　The Annual Meeting of the Gerontological Society of America (GSA)
◇開催地◇
　Indianapolis, USA
◇開催期間◇
　2022年11月2日 ～2022年11月6日

◇発表題目◇
　Socioeconomic Status, Lifestyle factors, and Brain Vulnerability among Japanese and Swedish female

◇発表内容◇
Females and populations of low socioeconomic status (SES) are at risk of Alzheimer's disease (AD) and related dementia. For example, the prevalence of AD among those aged 60 to 69 is almost twice higher in females than in males. Here, we hypothesize that SES is inversely associated with the cognitive performance of older females; furthermore, lifestyle and related diseases account for the effect of SES on brain cognition. To test these hypotheses, we horizontally compared Japanese and Swedish community cohorts, with the aim of describing the common and/or distinct socio-biological features underpinning dementia vulnerability. Brain structure was measured by regional gray matter (GM) volume and GM surface thickness obtained from T1 weighted magnetic resonance imaging scans. Cognition was evaluated by the Mental State Examination score. The relationships between SES-lifestyle-brain cognition were modeled by structural equations. Additionally, we used voxel-based morphometric analysis to detect locations in the brain where GM volume and surface thickness was affected by SES. Our findings indicate that lifestyle-related diseases (DCI in figure1), and not direct lifestyle indicators, are involved in the pathways linking SES to GM volume (not surface thickness). Likewise, the GM volume measure was better than the surface thickness at predicting the effect of SES at the whole brain level in both cohorts (Figure 2). We found no single risk factor or protective factor that could adequately explain the disparities due to low SES. For dementia prevention, older females in high-income countries such as Japan and Sweden may benefit more from disease control initiatives targeting obesity, diabetes, hypertension, and depressive disorders. Moreover, our results suggest that a healthier lifestyle does not necessarily guarantee better brain cognitive outcomes in response to low SES.

◇今回の発表によって得られた成果及び問題点◇
Beginning from the fundamental methodological perspective, the cross-sectional analysis in our study precludes causal inferences to explain brain-cognitive variation due to SES and lifestyle engagement. However, findings that are consistent across two different cultural backgrounds and races could be the basis for policymaking. Second, the different definitions of SES in the two cohorts may confound the results and tend to be underestimated or exaggerate. Future studies using the same material should seek to eliminate confounding noise to capture SES effects.

◇今後の研究目標及び課題◇
From the whole picture at GSA, I realized that the trend in gerontological studies is first, to be pragmatic and feasible to real-world implications. Studies that start from the statistical association should go beyond solutions on community. Researchers at GSA highlighted the importance to translate academic problems into real community-based interventions, always considering ‘how’ and ‘what’ is valued for the general public.