Serum β-amyloid 1–42 Levels as Alternative Non-invasive Screening Biomarker for Alzheimer’s Disease and Vascular Dementia in Indonesian Elderly Population

Indah Aprianti Putri (Doctoral Program of Medical Science, Faculty of Medicine, Universitas Airlangga, Jl. Prof. Dr. Moestopo No.47, Surabaya 60132)
Huda Shalahuddin Darusman (Faculty of Veterinary medicine, IPB University, Jl. Agatis, Bogor 16680)
Muhammad Hamdan (Department of Neurology, Faculty of Medicine, Universitas Airlangga, Jl. Prof. Dr. Moestopo No.47, Surabaya 60132)
Pukovisa Prawiroharjo (Neurology Department, Faculty of Medicine, Universitas Indonesia, Jl. Salemba Raya No.6, Jakarta 10430)
Budi Utomo (Department of Public Health, Faculty of Medicine, Universitas Airlangga, Jl. Mayjen Prof. Dr. Moestopo No.47, Surabaya 60132)
Jusak Nugraha (Department of Clinical Pathology, Faculty of Medicine, Universitas Airlangga, Jl. Mayjen Prof. Dr. Moestopo No.47, Surabaya 60132)
Yohanna Kusuma (Department of Neurology, Faculty of Medicine, Universitas Airlangga, Jl. Prof. Dr. Moestopo No.47, Surabaya 60132)
Nurrani Mustika Dewi (Prodia Education and Research Institute, Jl. Kramat Raya No. 150, Jakarta 10430)
Ferry Sandra (Department of Biochemistry and Molecular Biology, Division of Oral Biology, Faculty of Dentistry, Universitas Trisakti, Jl. Kyai Tapa No. 260, Jakarta 11440)

The Indonesian Biomedical Journal
Vol 17, No 6 (2025)

BACKGROUND: Alzheimer’s disease (AD) and vascular dementia (VaD) impose a substantial public health burden in Indonesia; however, accessible blood-based biomarkers for early screening remain limited. Although cerebrospinal fluid β-amyloid 1–42 is an established biomarker, its invasive nature restricts its use for population-level screening. Therefore, it is necessary to have locally-produced serum β-amyloid 1–42 ELISA kit that is specifically designed for Indonesian elderly population. In this study, a locally-produced β-amyloid 1–42 ELISA kit was validated and used for the screening of AD, VaD and mild cognitive impairment (MCI) Indonesian population.METHODS: A cross-sectional study including 166 subjects: 31 AD, 34 VaD, 34 MCI patients, and 67 cognitively normal controls was conducted. All participants underwent cognitive assessments including Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment-Indonesian version (MoCA-Ina), as well as brain magnetic resonance imaging (MRI) 3-Tesla for the assessment of medial temporal atrophy/white matter changes. Fasting venous blood sampling was taken from each subjects for the measurement of serum β-amyloid 1-42 measurement using locally-produced ELISA kit.RESULTS: Median serum β-amyloid 1–42 levels were 11.03, 10.99, and 10.99 pg/mL for the AD, VaD, and MCI subjects, respectively. The β-amyloid 1–42 levels were correlated with MMSE scores in all group (AD: r=−0.455, p=0.010; VaD: r=−0.419, p=0.014; MCI: r=−0.412, p=0.015). The validity analysis of the locally-produced serum β-amyloid 1–42 ELISA kit, showed sensitivity of 94.12% (95% CI: 87.3–97.9), specificity of 80.36% (95% CI: 72.4–86.8), and diagnostic accuracy of 83.56% (95% CI: 77.2–88.5).CONCLUSION: Serum β-amyloid 1–42 levels are lower in AD and VaD subjects compared to MCI and control subjects. Serum β-amyloid 1-42 is inversely correlated with cognitive function across all groups based on MMSE score. Additionally, the locally-produced β-amyloid 1-42 ELISA kit demonstrated sensitivity of 94.12% and specificity of 80.36%, meeting Global CEO Initiative Consensus for pre-screening tools, supporting its potential as a scalable, non-invasive screening biomarker in Indonesian primary care settings.KEYWORDS: G-banding karyotyping, next generation sequencing, non-invasive prenatal testing