Three‐Objects‐Three‐Places Test: Association with Alzheimer’s Disease Biomarkers

Abstract

AbstractBackgroundThe Three‐Objects‐Three‐Places Psychological Test (3O3P) assesses episodic memory and has been developed to screen for Alzheimer’s Disease (AD). To perform the test, the clinician shows the patient three objects and hides them in three separate locations. The patient is later asked what the objects and hiding places were, and which object was hidden where, producing a score out of 9. The aim of this study was to investigate if 3O3P scores were associated with common AD biomarkers to test its potential efficacy in detection of AD pathology, and how these associations compared with other common AD neuropsychological tests.Method166 patients from the Geneva Memory Centre cohort (106 MCI, 19 dementia, and 41 unimpaired) who underwent amyloid‐PET, tau‐PET, MRI, as well as clinical and neuropsychological assessments, were included. The biomarkers tested included amyloid (A) and tau (T) load, and cortical thickness (N). Associations between these biomarkers and 3O3P scores, MMSE and delayed total recall scores (DTR; extracted from the 16‐item Free and Cued Recall) were tested. The associations between biomarkers and test scores were investigated using linear regression.ResultMean patient age was 71 years, 52% were female, and mean years of education was 14. When controlling for age and education, 3O3P scores were negatively associated with amyloid (b = ‐0.02, p<0.001), tau load (b = ‐4.14, p<0.001), and positively with cortical thickness (b = 7.21, p<0.001). Similar trends were seen between these biomarkers and MMSE (A: b = ‐0.02; T: b = ‐5.21; N: b = 8.18, p<0.001) and DTR scores (A: b = ‐0.03; T: b = ‐5.28; N: b = 10.2, p<0.001).ConclusionThese preliminary findings indicate that 3O3P scores correlate significantly with the AD biomarkers tested, as do MMSE and DTR scores. However, the 3O3P test carries advantages, such as its short duration, easy administration, and not requiring the examiner to purchase equipment or score sheets. Further analysis is needed to clarify the relationship between 3O3P scores and AD biomarkers.