LAUSR

Key Points Question Can plasma biomarker analytes be used in a low-resource community to improve clinical accuracy in diagnosing Alzheimer disease (AD)? Findings In this decision analytical modeling study of 746 Caribbean Hispanic individuals from the Dominican Republic and New York, a panel of plasma biomarkers, including phosphorylated tau181 (P-tau181) and the ratio of P-tau181 to amyloid-β Aβ42, identified biological evidence of AD. A proportion of asymptomatic individuals without dementia had biomarker evidence of AD and may be presymptomatic, while a proportion of affected individuals with dementia lacked biomarker evidence of AD and may have other dementia disorders. Meaning These findings suggest that plasma biomarkers can improve the specificity of the clinical diagnosis of AD and can detect biological evidence of the disease in asymptomatic individuals in a low-resource environment where other types of diagnostic procedures are limited.