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Background: Subjective Cognitive Decline (SCD) may represent the onset of cognitive decline before impairment on standard cognitive tests occurs (Jessen et al., 2014). Previous cross‐sectional studies were shown to have limited ability to capture objective differences in cognitive performance between groups with and without SCD (Cacciamani et al., 2017). Understanding the interplay between changes in subjective memory ratings and objective cognitive function over time may have utility in identifying people at risk of dementia. Method: 370 cognitively normal (CN) individuals with complete cognitive data (Table 1 for characteristics) from Insight 46, a longitudinal neuroscience sub‐study of the MRC National Survey for Health and Development (the British 1946 Birth Cohort), underwent cognitive, clinical, and physical assessments, and neuroimaging (combined MRI/18F‐Florbetapir‐PET). SCD was measured using MyCog (Rami et al., 2014) a validated tool, from the SCD‐Questionnaire, where higher scores indicate greater subjective complaints. Linear regression models were used to test whether longitudinal cognitive change as measured using the Preclinical Alzheimer Cognitive Composite (PACC) and a visual short‐term memory binding task were influenced by baseline MyCog and whether there are parallel associations between rates of change in MyCog and longitudinal cognitive change. Covariates were sex, age at baseline visit, childhood cognitive ability, educational attainment, and adult socioeconomic position. Result: Baseline MyCog scores did not predict rates of change in PACC or visual short‐term memory binding outcome measures (Table 2). Rates of MyCog change alone did not predict rate of change in PACC, localisation error, total correct number of trials or proportion of misbinding errors (Table 3). However, we observed an interaction effect with baseline amyloid‐b status, whereby greater rates of subjective memory concerns predicted faster rates of decline in the proportion of misbinding errors in amyloid‐b positive participants only (Table 3; Figure 1). Conclusion: These findings suggest that higher amyloid‐b burden in CN individuals with subjective memory complaints is associated with faster rates of decline in visual working memory. Corroborating previous reports that feature binding tasks can objectify subtle cognitive deficits found in SCD (Koppara et al., 2015) and serve as a promising tool for identifying people at risk of dementia. [ABSTRACT FROM AUTHOR]

Background: Peripheral hearing impairment has been proposed as a risk factor for dementia. However, the relationship between hearing ability, neurodegeneration and cognitive decline, and the extent to which pathological processes associated with increased risk of specific causes of dementia, such as β‐amyloid and small vessel disease, influence these relationships, is unclear. Method: Data were analysed from 287 cognitively normal adults born in the same week of 1946 who underwent pure tone audiometry testing at baseline (mean age = 70.6 years), with cognitive assessment and brain imaging at baseline and at follow‐up on average 2.4 years later. Peripheral hearing impairment was defined as a pure tone average of greater than 25 decibels in the best hearing ear. Rates of change for whole brain, hippocampal and ventricle volume were estimated from structural MRI using the Boundary Shift Integral. Cognition was assessed using the Pre‐clinical Alzheimer's Cognitive Composite. Regression models were performed to evaluate how baseline hearing impairment associated with subsequent brain atrophy and cognitive decline after adjustment for a range of variables including baseline β‐amyloid deposition (assessed using florbetapir‐PET) and baseline small vessel disease burden (estimated using white matter hyperintensity volume). Results: 111 out of 287 participants were defined as having peripheral hearing impairment. Hearing impaired individuals demonstrated faster rates of whole brain atrophy (p = 0.031 – figure/table 1) compared with those with normal hearing. Peripheral hearing impairment did not predict change in PACC performance, but there was evidence of an interaction between hearing impairment and whole brain atrophy rates in terms of effect on change in PACC performance. Specifically, faster rates of whole brain atrophy predicted greater cognitive decline in participants with hearing impairment (p = 0.004), whilst there was no evidence of an association between cognitive change and atrophy in participants with preserved hearing (figure/table 2). There was no evidence that β‐amyloid deposition or white matter hyperintensity volume modified these relationships. Conclusion: We present evidence of associations between peripheral hearing ability at age 70, brain atrophy and cognitive decline independent of β‐amyloid and small vessel disease, suggesting hearing may associate with brain health via mechanisms distinct from those typically implicated in pre‐clinical Alzheimer's disease and vascular cognitive impairment. [ABSTRACT FROM AUTHOR]