In the past 5 years, we have witnessed the first approved Alzheimer disease (AD) disease-modifying therapy and the development of blood-based biomarkers (BBMs) to aid the diagnosis of AD. For many reasons, including accessibility, invasiveness and cost, BBMs are more acceptable and feasible for patients than a lumbar puncture (for cerebrospinal fluid collection) or neuroimaging. However, many questions remain regarding how best to utilize BBMs at the population level. In this Review, we outline the factors that warrant consideration for the widespread implementation and interpretation of AD BBMs. To set the scene, we review the current use of biomarkers, including BBMs, in AD. We go on to describe the characteristics of typical patients with cognitive impairment in primary care, who often differ from the patient populations used in AD BBM research studies. We also consider factors that might affect the interpretation of BBM tests, such as comorbidities, sex and race or ethnicity. We conclude by discussing broader issues such as ethics, patient and provider preference, incidental findings and dealing with indeterminate results and imperfect accuracy in implementing BBMs at the population level.

在过去的 5 年里，我们见证了第一个获批的阿尔茨海默病 (AD) 疾病缓解疗法以及有助于诊断 AD 的血液生物标志物 (BBM) 的开发。出于多种原因，包括可及性、侵入性和成本，BBM 比腰椎穿刺（用于脑脊液采集）或神经影像学更容易被患者接受和可行。然而，关于如何在人群层面最好地利用 BBM 仍然存在许多问题。在本次审查中，我们概述了 AD BBM 的广泛实施和解释需要考虑的因素。为了了解这一情况，我们回顾了生物标记物（包括 BBM）在 AD 中的当前使用情况。我们继续描述初级保健中典型认知障碍患者的特征，这些患者通常与 AD BBM 研究中使用的患者群体不同。我们还考虑可能影响 BBM 测试解释的因素，例如合并症、性别和种族或民族。最后，我们讨论了更广泛的问题，例如道德、患者和提供者的偏好、偶然发现以及处理在人群层面实施 BBM 时的不确定结果和不完美的准确性。