005) with increased pre-loss grief in caregivers of older adults with DLB. There was no significant difference in caregiver burden, well-being, or depression according to the various stages of DLB (mild, moderate, severe, deceased) in the care recipients. There was no significant difference in pre-loss grief in caregivers of DLB care recipients compared to caregivers of patients with other dementias. Assessment of DLB caregivers and appropriate interventions should be conducted to reduce their burden and emotional distress to decrease the incidence of pre-loss grief.Assessment of DLB caregivers and appropriate interventions should be conducted to reduce their burden and emotional distress to decrease the incidence of pre-loss grief. Previous studies reported default mode network (DMN) and limbic network (LIN) brain perfusion deficits in patients with amnestic mild cognitive impairment (aMCI), frequently a prodromal stage of Alzheimer's disease (AD). However, the validity of these measures as AD markers has not yet been tested using MRI arterial spin labeling (ASL). To investigate the convergent and discriminant validity of DMN and LIN perfusion in aMCI. We collected core AD markers (amyloid-β 42 [Aβ42], phosphorylated tau 181 levels in cerebrospinal fluid [CSF]), neurodegenerative (hippocampal volumes and CSF total tau), vascular (white matter hyperintensities), genetic (apolipoprotein E [APOE] status), and cognitive features (memory functioning on Paired Associate Learning test [PAL]) in 14 aMCI patients. Cerebral blood flow (CBF) was extracted from DMN and LIN using ASL and correlated with AD features to assess convergent validity. Discriminant validity was assessed carrying out the same analysis with AD-unrelated features, i.e., somatomotor and visual networks' perfusion, cerebellar volume, and processing speed. Perfusion was reduced in the DMN (F = 5.486, p = 0.039) and LIN (F = 12.678, p = 0.004) in APOE ɛ4 carriers compared to non-carriers. LIN perfusion correlated with CSF Aβ42 levels (r = 0.678, p = 0.022) and memory impairment (PAL, number of errors, r = -0.779, p = 0.002). No significant correlation was detected with tau, neurodegeneration, and vascular features, nor with AD-unrelated features. Our results support the validity of DMN and LIN ASL perfusion as AD markers in aMCI, indicating a significant correlation between CBF and amyloidosis, APOE ɛ4, and memory impairment.Our results support the validity of DMN and LIN ASL perfusion as AD markers in aMCI, indicating a significant correlation between CBF and amyloidosis, APOE ɛ4, and memory impairment. Current and future incidence and prevalence estimates of dementia are essential for public health planning. The objective was to establish prediction model of incidence and estimate the prevalence of dementia in the Chinese and worldwide population from 2020 to 2050. A model-based method was used to project the dementia prevalence from 2020 to 2050 in China, which required incidence, the mortality rate for individual without dementia, and the relative risk of death. Furthermore, we detected the impact of intervention on the prevalence projection for dementia using a simulation method. We applied the same method to other projections worldwide. In 2020, the model predicted 16.25 million (95%confidence interval 11.55-21.18) persons with dementia in China. By 2050, this number would increase by approximately three-fold to 48.98 million (38.02-61.73). Through data simulation, if the incidence of dementia decreased by 10%every 10 years from 2020 after intervention and prevention, the number of dementia cases by 2050 was reduced by 11.96 million. see more This would reduce the economic burden by US $639.04 billion. In addition, using this model, dementia cases grew relatively slowly over the next few decades in the United States of America, the United Kingdom, and Japan, with percentage changes of 100.88%, 65.93%, and 16.20%, respectively. The number of people with dementia in China is large and will continue to increase rapidly. Effective interventions could reduce the number of patients drastically. Therefore, prevention and control strategies must be formulated urgently to reduce the occurrence of dementia.The number of people with dementia in China is large and will continue to increase rapidly. Effective interventions could reduce the number of patients drastically. Therefore, prevention and control strategies must be formulated urgently to reduce the occurrence of dementia. Cyclin-dependent kinase inhibitor 2A (CDKN2A) is an important gene in cellular senescence and aging. This study assessed the utility of blood CDKN2A mRNA expression levels and methylation status as a potential biomarker for aging and the pathogenesis of Alzheimer's disease (AD). The correlation between CDKN2A mRNA expression levels and age was examined in 45 healthy subjects, after which mRNA expression levels were compared among 46 AD patients, 20 mild cognitive impairment due to AD patients, 21 Parkinson's disease patients, 21 dementia with Lewy bodies patients, and 55 older healthy controls. The methylation rates of the second exon of the CDKN2A gene, known to influence its expression levels, was also examined. A significant correlation between CDKN2A mRNA expression levels and age was found (Spearman's rank correlation coefficient r = 0.407, p = 0.005). CDKN2A mRNA expression levels in blood were significantly decreased in AD patients, although those of healthy controls were significantly increased with age. Further, only in AD patients were CDKN2A mRNA expression levels significantly and positively correlated with methylation rates. Although further research with a larger sample size is needed to elucidate the relationships between CDKN2A gene expression in blood and the development of other neurodegenerative diseases, CDKN2A mRNA expression in blood may be a biomarker for differentiating AD from normal aging and other neurodegenerative diseases.Although further research with a larger sample size is needed to elucidate the relationships between CDKN2A gene expression in blood and the development of other neurodegenerative diseases, CDKN2A mRNA expression in blood may be a biomarker for differentiating AD from normal aging and other neurodegenerative diseases.