Gao Yaqing, Andrews Shea, Daghlas Iyas, Brenowitz Willa D, Raji Cyrus A, Yaffe Kristine, Leng Yue
Nuffield Department of Population Health, University of Oxford, Oxford, UK.
Department of Psychiatry and Behavioral Sciences, University of California San Francisco, San Francisco, CA, USA.
Sleep. 2025 Jan 13;48(1). doi: 10.1093/sleep/zsae149.
The association between snoring, a very common condition that increases with age, and dementia risk is controversial. We aimed to investigate the observational and causal relationship between snoring and dementia, and to elucidate the role of body mass index (BMI).
Using data from 451 250 participants who were dementia-free at baseline, we examined the association between self-reported snoring and incident dementia using Cox proportional-hazards models. Causal relationship between snoring and Alzheimer's disease (AD) was examined using bidirectional two-sample Mendelian randomization (MR) analysis.
During a median follow-up of 13.6 years, 8325 individuals developed dementia. Snoring was associated with a lower risk of all-cause dementia (hazard ratio [HR] 0.93; 95% confidence interval [CI] 0.89 to 0.98) and AD (HR 0.91; 95% CI 0.84 to 0.97). The association was slightly attenuated after adjusting for BMI, and was stronger in older individuals, APOE ε4 allele carriers, and during shorter follow-up periods. MR analyses suggested no causal effect of snoring on AD; however, genetic liability to AD was associated with a lower risk of snoring. Multivariable MR indicated that the effect of AD on snoring was primarily driven by BMI.
The phenotypic association between snoring and lower dementia risk likely stems from reverse causation, with genetic predisposition to AD associated with reduced snoring. This may be driven by weight loss in prodromal AD. Increased attention should be paid to reduced snoring and weight loss in older adults as potential early indicators of dementia risk.
打鼾是一种非常常见的随年龄增长而增加的状况，其与痴呆风险之间的关联存在争议。我们旨在研究打鼾与痴呆之间的观察性和因果关系，并阐明体重指数（BMI）的作用。
我们使用来自451250名基线时无痴呆的参与者的数据，采用Cox比例风险模型研究自我报告的打鼾与新发痴呆之间的关联。使用双向双样本孟德尔随机化（MR）分析来研究打鼾与阿尔茨海默病（AD）之间的因果关系。
在中位随访13.6年期间，8325人患上痴呆。打鼾与全因痴呆风险较低相关（风险比[HR]0.93；95%置信区间[CI]0.89至0.98）以及与AD风险较低相关（HR 0.91；95%CI 0.84至0.97）。在调整BMI后，这种关联略有减弱，并且在老年人、APOE ε4等位基因携带者以及较短随访期内更强。MR分析表明打鼾对AD没有因果效应；然而，AD的遗传易感性与较低的打鼾风险相关。多变量MR表明AD对打鼾的影响主要由BMI驱动。
打鼾与较低痴呆风险之间的表型关联可能源于反向因果关系，AD的遗传易感性与打鼾减少相关。这可能是由前驱AD中的体重减轻所驱动。应更加关注老年人打鼾减少和体重减轻作为痴呆风险潜在早期指标的情况。
