Acceptable performance of blood biomarker tests of amyloid pathology - recommendations from the Global CEO Initiative on Alzheimer's Disease.

Anti-amyloid treatments for early symptomatic Alzheimer disease have recently become clinically available in some countries, which has greatly increased the need for biomarker confirmation of amyloid pathology. Blood biomarker (BBM) tests for amyloid pathology are more acceptable, accessible and scalable than amyloid PET or cerebrospinal fluid (CSF) tests, but have highly variable levels of performance. The Global CEO Initiative on Alzheimer's Disease convened a BBM Workgroup to consider the minimum acceptable performance of BBM tests for clinical use. Amyloid PET status was identified as the reference standard. For use as a triaging test before subsequent confirmatory tests such as amyloid PET or CSF tests, the BBM Workgroup recommends that a BBM test has a sensitivity of ≥90% with a specificity of ≥85% in primary care and ≥75-85% in secondary care depending on the availability of follow-up testing. For use as a confirmatory test without follow-up tests, a BBM test should have performance equivalent to that of CSF tests - a sensitivity and specificity of ~90%. Importantly, the predictive values of all biomarker tests vary according to the pre-test probability of amyloid pathology and must be interpreted in the complete clinical context. Use of BBM tests that meet these performance standards could enable more people to receive an accurate and timely Alzheimer disease diagnosis and potentially benefit from new treatments.

A holistic client-centred program for vulnerable frequent hospital attenders: cost efficiencies and changed practices.

OBJECTIVE: A small percentage of Australians frequently attend hospital emergency departments (ED) with potentially avoidable health crises. These individuals are termed 'vulnerable' due to their complex health and social needs. When these needs are unmanaged, unnecessary ED and hospital-admission costs are incurred. A holistic community-based program was developed to engage a cohort of vulnerable individuals in strategies to improve their health and health behaviours, and health service use. METHODS: A purposive sample of frequent ED attendees was identified in one Australian metropolitan health region. Core program elements included working with clients within their environment, problem solving, empowerment, education, goal setting and mentoring. Evaluation data included services provided for, and time spent with, clients; hospital admission and emergency department attendances and related costs; client engagement data; mental health measures; client stories and participant interviews. RESULTS: Data was analysed from 37 clients. On average, staff spent 34 hours with each client, costing approximately $1,700 each. Significant improvements resulted in client health and health behaviours. Crisis emergency department and inpatient admissions decreased, and planned outpatient clinic use increased. CONCLUSION: Low-cost community-based intervention for frequent ED attendees has the potential for significant tertiary hospital savings.