Prevalence And Determinants Of Agonistic Autoantibodies Against Alpha 1-Adrenergic Receptors In Patients Screened Positive For Dementia: Results From The Population-Based Delphi-Study

Background: There is a need to assess promising biomarkers for diagnosis and treatment response in real-life settings. Despite the important role of vascular risk factors, cardiovascular biomarkers have played a minor role in dementia research. Agonistic autoantibodies (agAAB) directed against G-protein-coupled receptors (GPCR) are discussed as modulators of pathology and clinical manifestation.Objective: 1) Describe prevalence of agAAB directed against GPCR, especially agABB against alpha 1-adrenergic receptors (alpha 1-AR-agAAB) and agABB directed against beta 2-adrenergic receptors (beta 2-AR-agAAB) and 2) identify factors associated with agAAB in people with dementia during routine care.Methods: Blood samples and data from 95 subjects who screened positive for dementia from a primary care cohort, analyzed using an enzyme-linked immunosorbent assay (ELISA) for detecting agAAB. Sociodemographic and clinical data were assessed, and medical records checked.Results: In 40 (42%) samples, agAAB was detected, with n= 29 (31%) representing alpha 1-AR-agAAB and n= 21 (22%) beta 2-AR-agAAB. There was no association between the presence of any antibody and a formal diagnosis of dementia. However, patients with coronary heart disease were more likely (OR = 4.23) to have alpha 1-AR-agAAB than those without coronary heart disease. There were no associations between agAAB and age, sex, education, or cognitive impairment.Discussion: For the first time, we show that autoantibodies have a significant prevalence in people with dementia in a routine care setting. Previous findings were restricted to highly selective samples. We replicated the association between alpha 1-AR-agAAB in patients with coronary heart diseases but were not able to find other factors associated with the presence of agAAB.