Predicting Alzheimer Dementia Risk With CSF, MRI Clinical Biomarkers
Identifying abnormal biomarkers may help predict which patients will progress from mild cognitive impairment to Alzheimer dementia.
The use of clinical biomarkers obtained from cerebrospinal fluid (CSF) and magnetic resonance imaging may be effective for predicting risk for and aiding in the clinical decision-making of Alzheimer disease (AD) dementia, according to study findings published in JAMA Neurology.
Researchers sought to develop biomarker-based prediction models, including a CSF (amyloid-β1-42, tau) model, a magnetic resonance imaging model, and a combined model, for AD dementia. Investigators included patients with mild cognitive impairment, evaluating data from the Amsterdam Dementia Cohort. Age, sex, and Mini-Mental State Examination (MMSE) scores were used to develop prognostic models for dementia.
Using only age, sex, and MMSE score, investigators discovered that the 3-year progression risk to AD dementia was 26% (95% CI, 19%-34%) in men who scored 29 on the MMSE (95% CI, 65%-84%). In addition, progression to AD dementia risk was 76% (95% CI, 65%-84%) among women with similar MMSE scores (1-year risk: 6% [95% CI, 4%-9%] to 24% [95% CI, 18%-32%]).
Abnormal MRI results were associated with 3- and 1-year progression to AD dementia risks of 86% (95% CI, 71%-95%) and 27% (95% CI, 17%-41%), respectively. In comparison, abnormal CSF test results correlated with an 82% (95% CI, 73%-89%) and 26% (95% CI, 20%-33%) risk. Normal magnetic resonance imaging results and cerebrospinal fluid test results at 3 years resulted in progression risks of 18% (95% CI, 13%-27%) and 6% (95% CI, 3%-9%), respectively.
The short mean 2.4-year follow-up period represents 1 of the prime limitations associated with the study's design.
On the basis of these initial findings, the study demonstrates the rationale behind using biomarker-based prediction models in AD dementia, including how these models could "facilitate application of magnetic resonance imaging and cerebrospinal fluid biomarkers in daily practice."
van Maurik IS, Zwan MD, Tijms BM, et al. Interpreting biomarker results in individual patients with mild cognitive impairment in the Alzheimer's Biomarkers in Daily Practice (ABIDE) project [published online October 16, 2017]. JAMA Neurol. doi:10.1001/jamaneurol.2017.2712