Title | Odor Identification Ability Predicts PET Amyloid Status and Memory Decline in Older Adults. |
Publication Type | Journal Article |
Year of Publication | 2018 |
Authors | Kreisl, WCharles, Jin, P, Lee, S, Dayan, ER, Vallabhajosula, S, Pelton, G, Luchsinger, JA, Pradhaban, G, Devanand, DP |
Journal | J Alzheimers Dis |
Volume | 62 |
Issue | 4 |
Pagination | 1759-1766 |
Date Published | 2018 |
ISSN | 1875-8908 |
Abstract | BACKGROUND: Odor identification deficits occur in Alzheimer's disease (AD), as measured by the 40-item University of Pennsylvania Smell Identification Test (UPSIT). OBJECTIVE: To determine if UPSIT scores predict amyloid-β (Aβ) status, determined by 11C-Pittsburgh Compound B PET. We also compared UPSIT scores to Aβ status in predicting future memory decline. METHODS: Subjects were recruited into a longitudinal clinical prediction study. We analyzed data from those who had UPSIT, cognitive testing, PIB PET, and at least 12 months' clinical follow-up. Forty-six amnestic mild cognitive impairment patients and 25 cognitively normal controls were included. Amyloid-positivity was defined as composite PIB standardized uptake value ratio >1.5. Logistic regression and Receiver Operating Characteristic Curve analyses tested the predictive utility of impaired olfaction (defined as UPSIT score RESULTS: High UPSIT scores predicted absence of amyloidosis on PET, with negative predictive value of 100%. Positive predictive value of low UPSIT scores on positive Aβ status was only 41%. Both low UPSIT score (OR = 4.301, 95% CI = 1.248, 14.821, p = 0.021) and positive PET scan (OR = 20.898, 95% CI = 2.222, 196.581, p = 0.008) predicted memory decline. CONCLUSION: Individuals with high UPSIT scores are less likely to have cerebral amyloidosis or experience memory decline. Therefore, UPSIT has potential as a screening tool to determine utility of Aβ PET in clinical practice or enrollment in clinical trials. Low UPSIT score is a non-specific marker of neurodegeneration that could indicate further workup in patients with memory complaints. |
DOI | 10.3233/JAD-170960 |
Alternate Journal | J. Alzheimers Dis. |
PubMed ID | 29614678 |
Grant List | K01 AG051348 / AG / NIA NIH HHS / United States R01 AG041795 / AG / NIA NIH HHS / United States |