Serum BP180 and BP230 autoantibodies in Alzheimer’s disease: diagnostic and cognitive associations in a retrospective study

Background To assess the prevalence and diagnostic value of serum anti-BP180 and anti-BP230 antibodies in Alzheimer’s Disease (AD) and their relationship with cognitive function. Methods We conducted a retrospective case–control study comprising 279 participants, including patients with clinically diagnosed AD and neurologically healthy controls, who were consecutively enrolled at the Third People’s Hospital, Hangzhou, China, between 2022 and 2024. Serum levels of anti-BP180 and anti-BP230 antibodies were quantified using enzyme-linked immunosorbent assays (ELISAs). Among patients with AD, the relationship between cognitive function, assessed by the Mini-Mental State Examination (MMSE), and serum antibody concentrations was further evaluated. Results After adjustment for age and sex, serum BP180 levels were significantly higher in AD patients compared with healthy controls ( β = 2.257, 95% CI: 1.102–3.412, p 0.001). Similarly, BP230 levels were also significantly elevated in AD patients ( β = 3.432, 95% CI: 0.395–6.468, p = 0.027). Multivariable logistic regression analysis identified BP180 (odds ratio OR = 1.149, 95% CI: 1.056–1.275, p = 0.004), age (OR = 1.176, 95% CI: 1.110–1.254, p 0.001), and female sex (OR = 5.318, 95% CI: 2.853–10.272, p 0.001) as independent predictors of AD. A predictive model incorporating BP180, age, and sex was subsequently developed, demonstrating good diagnostic performance with an area under the curve (AUC) of 0.798 (95% CI: 0.734–0.862). Compared with BP180 alone (AUC = 0.591) or BP230 alone (AUC = 0.598), the multivariable model showed significantly improved discriminative ability. In addition, both BP180 ( p 0.001) and BP230 ( p = 0.003) levels were significantly and negatively correlated with MMSE scores. Conclusion The multivariable model incorporating BP180, age, and sex demonstrated good discriminative performance in distinguishing AD patients from controls and outperformed individual biomarkers. Integrating clinical and serological markers may improve the diagnostic performance for AD.