The use of Alzheimer CSF biomarkers in daily clinical practice: Neuropsychiatry and behavioral neurology/Dementia

Background Currently, there is a discrepancy regarding whether CSF biomarkers (BM) in Alzheimer’s Disease (AD) should be applied generally in daily clinical practice, performed in high‐level clinical centres, or reserved for research only. The main objective is to assess the influence of these BM on the diagnosis of AD in daily clinical practice, analyzing the change or maintenance of the etiological diagnosis after the performance of the test. As a secondary objective, the type of patients requested to take this test will be assessed. Finally, the concordance between the test request and the recommendations from literature (Shaw et al, 2018) will be analyzed. Method This is an observational and retrospective study of patients referred to our hospital’s neurology department for suspected cognitive or behavioral impairment. The patients underwent a CSF study between the years 2014‐2019. For the etiological diagnosis, the most widespread diagnostic criteria were applied at that time (DSM‐IV and NIAA). Main variable: change of pre‐test vs post‐test diagnosis. Secondary variables: concordance with the recommendations, sex, age, symptoms or signs, MMSE, GDS. Result 102 patients were analyzed, 67.6 a ± 7.9 (49‐84), 53 % men, 75 % with memory loss and 33 % with neuro‐psychiatric symptoms. MMSE: 22 ± 5 (6‐30), GDS: 3 ± 1.2 (2‐6). There was a change in the etiological diagnosis in 39,2 % of the patients, especially when psychiatric disorder was the initial suspicion (34,2 %). There was a complete consistency with the recommendations from literature Conclusion The profile of the patient requested for testing was young (compared to the usual age of cognitive disorder), with memory complaints or neuro‐psychiatric symptoms, in the early clinical stages of the disease. The agreement with the recommendations is total. Our change in diagnosis is similar to the one found in other series in literature (Tabaraud et al, 2011), and close to clinical trials using amyloid BM. Therefore, it is believed that CSF BMs are clearly useful in their application under real clinical practice conditions.