NIHTB odor identification in African American older adults with and without aMCI

INTRODUCTION: Early detection of amnestic mild cognitive impairment (aMCI) is critical for intervention. While olfactory decline is a promising non-invasive marker of aMCI, research in underrepresented populations is limited. We evaluated the NIH Toolbox Odor Identification Test (NIHTB-OIT) in older African Americans.METHODS: Participants included 93 healthy agers (81.7% female; Mage=73.85, SDage=5.06) and 52 individuals with aMCI (69.2% female; Mage=74.37, SDage=5.26). NIHTB-OIT scores were analyzed using two-way ANCOVAs, adjusting for age and education. Receiver Operating Characteristic (ROC) analysis assessed diagnostic utility. APOE ε4 status was examined in a subset (64.8%).RESULTS: Healthy agers scored significantly higher than the aMCI group (p =.019), and females outperformed males (p =.031). ROC analysis showed significant but modest discrimination (AUC=.626, p =.010). An optimal cut-off score of 5.5 yielded 76.3% specificity and 40.4% sensitivity in differentiating aMCI from healthy agers. No significant differences were found by APOE ε4 status or diagnosis-by-sex interactions.DISCUSSION: The NIHTB-OIT differentiates aMCI from healthy aging in African American older adults. Its brevity, standardized scoring, and high specificity support its clinical utility as a rapid, non-invasive screening tool for community-based cognitive health assessments.