Willingness and barriers to blood-based biomarker testing of Alzheimer's disease in the general population in the Czech Republic.

BACKGROUND: Blood-based biomarkers (BBBM) for Alzheimer's disease (AD) are entering clinical practice with new clinical practice guidelines and the first FDA-approved blood test. Their implementation will depend not only on assay performance but also on public willingness, trust, and understanding of probabilistic results. We examined attitudes towards BBBM in the general population and psychosocial factors that may facilitate or hinder uptake. METHODS: We conducted an online cross-sectional survey among adults aged ≥ 35 years (M = 51.08, SD = 9.79) in the Czech Republic (N = 666). The survey assessed willingness to undergo BBBM testing, sociodemographic characteristics, experience with AD, depressive symptoms (Patient Health Questionnaire, PHQ-9), concerns about developing AD, and medical distrust (Medical Distrust Index, MDI). Logistic regression models (unweighted and weighted for gender and region) were estimated to examine the association with willingness. Open-ended responses were analyzed thematically to identify motivators and barriers. RESULTS: Overall, 92.8% of participants reported that they would undergo BBBM testing. Greater concern about developing AD was the strongest facilitator (OR = 1.59-2.34). Having AD in a close family member was associated with lower willingness (OR = 0.31-0.43), as was higher medical distrust (MDI OR = 0.79 in the fully weighted model). Education, age, gender, depressive symptoms, and AD knowledge were not significantly associated with willingness. Qualitative analyses showed that participants viewed BBBM as a way to "take action in time", "know one's health status" and "prepare for the future", whereas fear of AD, preference "not to know", perceived lack of treatment, test uncertainty/"only probability", and privacy concerns were common barriers. CONCLUSIONS: Public willingness to undergo BBBM testing is high, but psychosocial barriers, particularly familial experience of AD and medical distrust, may limit real-world uptake. Addressing these barriers through targeted education, probabilistic risk communication, and trusted primary-care pathways will be essential for the responsible implementation of BBBM in clinical practice.