Long-term Olfactory Functions in Patients with Subjective Cognitive Decline and Mild Cognitive Impairment

Abstract Introduction Olfactory function is known to be impaired in patients with Alzheimer’s disease (AD) as well subjective cognitive decline (SCD) and mild impairment (MCI), which are generally considered at-risk states for developing AD. The aim of the study at hand was identify predictors self-reported olfaction capability (SOC), perceiving specific odors (SRP), olfaction-related quality life (ORQ), odor identification (OIT) SCD, naMCI, aMCI. Methods sample consisted 33 88 43 aMCI who consulted Department Neurology, Medical University Vienna, due memory complaints between January 2001 May 2018. assessed objectively by means Sniffin’ Sticks test subjectively ASOF-scores SOC, SRP, ORQ two three points time, an average time interval 39 months first second examination, 24 third examination. Linear mixed models were used order clinical demographic variables mean ORQ, OIT throughout observation period. Results There a statistically significant — albeit small time-related SOC SCD group but not other groups. Throughout period, estimated significantly higher than naMCI after adjusting measurement covariates. Positive relationships all ASOF-scores, negative BDI-II positive relationship WST-IQ SRP identified. Conclusion significant, small, uncertain relevance measures olfactory SCD. Implications In subgroups, measured odor-identification scores have impact on over time. confirms previous observations regarding influence depression perception capabilities from cross-sectional studies.