Memory alteration test (M@T) is correlated with CSF biomarkers and neurodegeneration in patients with aMCI and AD in a low‐and‐middle‐ income country

Abstract

AbstractBackgroundAs new therapies become available, early detection of Alzheimer’s disease (AD) becomes increasingly important. However, the use of biomarkers or advanced imaging has not been fully implemented in low‐ and ‐middle income countries (LMICs), especially in Latin America. Given that brief cognitive tests (BCTs) are widely available and easy to administer, we evaluated the capacity of the AD‐focused BCT, the Memory Alteration Test (M@T), to detect AD, neurodegeneration markers in MRI, and its correlation with CSF biomarkers.MethodThis is a secondary analysis from a previously published cohort of 63 controls, 53 amnestic MCI (aMCI), and 69 AD patients. They underwent testing with the M@T and a complete neuropsychological battery. Total‐tau (t‐tau), phosphorylated tau (p‐tau) and β‐amyloid in CSF were measured in all included patients. Neurodegeneration was determined by Medial Temporal Atrophy (MTA) score in MRI. We used Receiver‐Operator Curves to determine the discriminative capacity of the total M@T score as well as its subdomains. We used the Pearson coefficient and performed a linear regression between total score and CSF biomarkers.ResultThe M@T score had an AUC of 0.994 to discriminate between controls and cognitively impaired (aMCI or AD) patients, and an AUC of 0.98 to differentiate between aMCI and AD patients. Free‐recall and cued recall had the highest AUCs of all subdomains. Total score was strongly correlated with t‐tau (‐0.77) and p‐tau (‐0.72), and moderately correlated with β‐amyloid (0.66). The AUC for discrimination of neurodegeneration was 0.87.ConclusionThe M@T brief cognitive test had excellent discrimination of MCI and AD patients in an LMIC. It was also strongly correlated with CSF biomarkers and had good discrimination of Neurodegeneration. The recall sub‐domains presented the highest diagnostic capacity. Its use as a screening tool could allow LMICs to enrich samples of patients who may benefit from new available therapies.