Subjective cognitive decline and risk of MCI: The Mayo Clinic Study of Aging

© 2018 American Academy of Neurology. OBJECTIVE: We investigated different dimensions of subjective cognitive decline (SCD) to determine which was the best prognostic risk factor for incident mild cognitive impairment (MCI) among cognitively unimpaired participants. METHODS: We included 1,167 cognitively unimpaired participants, aged 70 to 95 years, from the Mayo Clinic Study of Aging based on 2 concurrent SCD scales (part of the Blessed memory test and the 39-item Everyday Cognition [ECog] scale, which included a validated 12-item derivative) and a single question assessing worry about cognitive decline. We evaluated multiple ways to dichotomize scores. In continuous models, we compared average scores on 4 ECog domains and multidomain (39- and 12-item) ECog scores. Cox proportional hazards models were used to assess the association between each measure and risk of MCI in models adjusted for objective memory performance, depression, anxiety, sex, APOE ε4 carriership, and medical comorbidities. RESULTS: It was possible to select a substantial group of participants (14%) at increased risk of incident MCI based on combined baseline endorsement of any consistent SCD on the ECog (any item scored ≥3; 12-item ECog hazard ratio [HR] 2.17 [95% confidence interval 1.51-3.13]) and worry (HR 1.79 [1.24-2.58]) in an adjusted model combining these dimensions. In continuous models, all ECog domains and the multidomain scores were associated with risk of MCI with a small advantage for multidomain SCD (12-item ECog HR 2.13 [1.36-3.35] per point increase in average score). Information provided by the informant performed comparable to self-perceived SCD. CONCLUSION: Prognostic value of SCD for incident MCI improves when both consistency of SCD and associated worry are evaluated

Distribution and predictive value of all self-perceived SCD and iSCD measures for incident MCI in the MCSA

Table 1: Distribution and predictive value of SCD scores. Table 2: Distribution and predictive value of iSCD scores

Subjective cognitive decline and risk of MCI: The Mayo Clinic Study of Aging

© 2018 American Academy of Neurology. OBJECTIVE: We investigated different dimensions of subjective cognitive decline (SCD) to determine which was the best prognostic risk factor for incident mild cognitive impairment (MCI) among cognitively unimpaired participants. METHODS: We included 1,167 cognitively unimpaired participants, aged 70 to 95 years, from the Mayo Clinic Study of Aging based on 2 concurrent SCD scales (part of the Blessed memory test and the 39-item Everyday Cognition [ECog] scale, which included a validated 12-item derivative) and a single question assessing worry about cognitive decline. We evaluated multiple ways to dichotomize scores. In continuous models, we compared average scores on 4 ECog domains and multidomain (39- and 12-item) ECog scores. Cox proportional hazards models were used to assess the association between each measure and risk of MCI in models adjusted for objective memory performance, depression, anxiety, sex, APOE ε4 carriership, and medical comorbidities. RESULTS: It was possible to select a substantial group of participants (14%) at increased risk of incident MCI based on combined baseline endorsement of any consistent SCD on the ECog (any item scored ≥3; 12-item ECog hazard ratio [HR] 2.17 [95% confidence interval 1.51-3.13]) and worry (HR 1.79 [1.24-2.58]) in an adjusted model combining these dimensions. In continuous models, all ECog domains and the multidomain scores were associated with risk of MCI with a small advantage for multidomain SCD (12-item ECog HR 2.13 [1.36-3.35] per point increase in average score). Information provided by the informant performed comparable to self-perceived SCD. CONCLUSION: Prognostic value of SCD for incident MCI improves when both consistency of SCD and associated worry are evaluated

Indicators of amyloid burden in a population-based study of cognitively normal elderly

Objectives: Secondary prevention trials in subjects with preclinical Alzheimer disease may require documentation of brain amyloidosis. The identification of inexpensive and noninvasive screening variables that can identify individuals who have significant amyloid accumulation would reduce screening costs. Methods: A total of 483 cognitively normal (CN) individuals, aged 70-92 years, from the population-based Mayo Clinic Study of Aging, underwent Pittsburgh compound B (PiB)-PET imaging. Logistic regression determined whether age, sex, APOE genotype, family history, or cognitive performance was associated with odds of a PiB retention ratio \u3c1.4 and \u3c1.5. Area under the receiver operating characteristic curve (AUROC) evaluated the discrimination between PiBpositive and -negative subjects. For each characteristic, we determined the number needed to screen in each age group (70-79 and 80-89) to identify 100 participants with PiB \u3c1.4 or \u3c1.5. Results: A total of 211 (44%) individuals had PiB \u3c1.4 and 151 (31%) \u3c1.5. In univariate and multivariate models, discrimination was modest (AUROC ̃0.6-0.7). Multivariately, age and APOE best predicted odds of PiB \u3c1.4 and \u3c1.5. Subjective memory complaints were similar to cognitive test performance in predicting PiB \u3c1.5. Indicators of PiB positivity varied with age. Screening APOE ε4 carriers alone reduced the number needed to screen to enroll 100 subjects with PIB \u3c1.5 by 48% in persons aged 70-79 and 33% in those aged 80-89. Conclusions: Age and APOE genotype are useful predictors of the likelihood of significant amyloid accumulation, but discrimination is modest. Nonetheless, these results suggest that inexpensive and noninvasive measures could significantly reduce the number of CN individuals needed to screen to enroll a given number of amyloid-positive subjects. © 2012 by AAN Enterprises, Inc