Lower odor identification in subjective cognitive decline: a meta-analysis.

ABSTRACT:

Introduction

Odor identification correlates with Alzheimer's disease (AD) biomarkers, and its decline may emerge before measurable cognitive deficits - as early as the subjective cognitive decline (SCD) stage. We aimed to compare odor identification between SCD and cognitively normal (CN) stages.

Methods

A systematic search of four databases identified studies assessing olfactory identification and cognitive screening in individuals aged 50+. A random-effects meta-analysis was performed on 11 studies (660 SCD, 574 CN).

Results

Individuals with SCD exhibited lower olfactory identification scores compared to CN participants (SMD = -0.67, 95% CI [-1.31, -0.03], p = 0.04). Meta-regression revealed a negative association (β = -1.79, p = 0.02) between c

SUBMITTER: Jobin B 

PROVIDER: S-EPMC12358221 | biostudies-literature | 2025 Jul-Sep

REPOSITORIES: biostudies-literature