Du Lianlian, Yu Lei, Wang Tianhao, Boyle Patricia A, Barnes Lisa L, Marquez David X, Bennett David A
Rush Alzheimer's Disease Center, Rush University Medical Center; Chicago, IL, USA.
Department of Neurological Sciences, Rush University Medical Center; Chicago, IL, USA.
medRxiv. 2025 Sep 4:2025.08.29.25334749. doi: 10.1101/2025.08.29.25334749.
To estimate the lifetime risk of dementia and mild cognitive impairment (MCI) from age 55 to 105, accounting for competing risk of death, and to examine differences by sex and race.
We analyzed data from five harmonized longitudinal cohort studies at the Rush Alzheimer's Disease Center, including 4611 community dwelling older adults for lifetime dementia risk estimation and 3915 for lifetime MCI risk estimation. Incident dementia and MCI were identified through annual clinical evaluations. Nonparametric cumulative incidence function curves estimated lifetime risk, adjusting for competing risk of death and left truncation. Additional analyses assessed lifetime risk from index ages 55, 65, 75, and 85 and examined differences by sex and race.
The lifetime risk of incident dementia after age 55 was 43% (95% CI: 38-47), with a median age at diagnosis of 88 years(IQR: 83-92). For MCI, the lifetime risk was 62% (95% CI: 57-67), with a median age at diagnosis of 86 years(IQR: 80-90). Females had higher lifetime risks than males for both dementia (45% vs. 39%) and MCI (63% vs. 60%). Racial differences were smaller for dementia (45% in Black vs. 44% in White participants). For MCI, Black adults had higher lifetime risk before age 90.
These findings extend dementia lifetime risk estimation beyond age 90 among diverse older adults to provide lifetime risk estimates for MCI while accounting for the competing risk of death, highlighting the importance of prevention, and equitable public health strategies to reduce the burden of cognitive impairment.
估计55岁至105岁人群患痴呆症和轻度认知障碍（MCI）的终生风险，同时考虑死亡的竞争风险，并研究性别和种族差异。
我们分析了拉什阿尔茨海默病中心五项协调的纵向队列研究的数据，其中4611名社区居住的老年人用于终生痴呆症风险估计，3915名用于终生MCI风险估计。通过年度临床评估确定新发痴呆症和MCI。非参数累积发病率函数曲线估计终生风险，并对死亡的竞争风险和左截断进行调整。额外的分析评估了55岁、65岁、75岁和85岁起始年龄的终生风险，并研究了性别和种族差异。
55岁以后患新发痴呆症的终生风险为43%（95%CI：38-47），诊断时的中位年龄为88岁（IQR：83-92）。对于MCI，终生风险为62%（95%CI：57-67），诊断时的中位年龄为86岁（IQR：80-90）。女性患痴呆症（45%对39%）和MCI（63%对60%）的终生风险均高于男性。痴呆症的种族差异较小（黑人参与者为45%，白人参与者为44%）。对于MCI，黑人成年人在90岁之前的终生风险较高。
这些发现将痴呆症终生风险估计扩展到90岁以上的不同老年人，同时考虑死亡的竞争风险，为MCI提供终生风险估计，强调了预防以及公平的公共卫生策略对减轻认知障碍负担的重要性。
