Edentulism, blood‐based neurodegenerative biomarkers, and 10‐year dementia risk: A mediation analysis in a nationally representative United States cohort
Xiang Qi, Ruotong Liu, Daniel W. Belsky, Qu Tian, Huabin Luo, Yunrui Liu, Zhijing Xu, Kenneth M. Langa, Bei WuAbstract
INTRODUCTION
Tooth loss is associated with dementia risk, but mechanisms remain unclear. We examined whether blood‐based neurodegenerative biomarkers mediate the edentulism–cognition association.
METHODS
Among 4238 Health and Retirement Study participants aged 50+, we linked edentulism (2012), biomarkers (neurofilament light chain [NfL], glial fibrillary acidic protein [GFAP], phosphorylated tau‐181, and amyloid‐β [Aβ] 42/40; 2016), and 10‐year cognitive outcomes (2012–2022).
RESULTS
Edentulism was associated with higher NfL ( β = 4.21) and GFAP ( β = 8.06), but not pTau‐181 or Aβ42/40, and predicted cognitive impairment (hazard ratio [HR] 1.49) and dementia (HR 1.28). GFAP mediated 9.8% and 12.0% of the cognitive impairment and dementia associations, respectively; NfL mediated 9.8% of the dementia association but not cognitive impairment.
CONCLUSION
In this observational cohort, elevated NfL and GFAP were associated with, and accounted for a small proportion of, the edentulism–cognition association. These associative findings support further study of oral health in dementia prevention but do not establish a causal effect.