Outcome over seven years of healthy adults with and without subjective cognitive impairment

Silberstein Aging and Dementia Research Center, New York University School of Medicine, New York, USA.
Alzheimer's & dementia: the journal of the Alzheimer's Association (Impact Factor: 12.41). 01/2010; 6(1):11-24. DOI: 10.1016/j.jalz.2009.10.002
Source: PubMed


Subjective cognitive impairment (SCI) in older persons without manifest symptomatology is a common condition with a largely unclear prognosis. We hypothesized that (1) examining outcome for a sufficient period by using conversion to mild cognitive impairment (MCI) or dementia would clarify SCI prognosis, and (2) with the aforementioned procedures, the prognosis of SCI subjects would differ significantly from that of demographically matched healthy subjects, free of SCI, termed no cognitive impairment (NCI) subjects.
A consecutive series of healthy subjects, aged > or =40 years, presenting with NCI or SCI to a brain aging and dementia research center during a 14-year interval, were studied and followed up during an 18-year observation window. The study population (60 NCI, 200 SCI, 60% female) had a mean age of 67.2 +/- 9.1 years, was well-educated (mean, 15.5 +/- 2.7 years), and cognitively normal (Mini-Mental State Examination, 29.1 +/- 1.2).
A total of 213 subjects (81.9% of the study population) were followed up. Follow-up occurred during a mean period of 6.8 +/- 3.4 years, and subjects had a mean of 2.9 +/- 1.6 follow-up visits. Seven NCI (14.9%) and 90 SCI (54.2%) subjects declined (P < .0001). Of NCI decliners, five declined to MCI and two to probable Alzheimer's disease. Of SCI decliners, 71 declined to MCI and 19 to dementia diagnoses. Controlling for baseline demographic variables and follow-up time, Weibull proportional hazards model revealed increased decline in SCI subjects (hazard ratio, 4.5; 95% confidence interval, 1.9-10.3), whereas the accelerated failure time model analysis with an underlying Weibull survival function showed that SCI subjects declined more rapidly, at 60% of the rate of NCI subjects (95% confidence interval, 0.45-0.80). Furthermore, mean time to decline was 3.5 years longer for NCI than for SCI subjects (P = .0003).
These results indicate that SCI in subjects with normal cognition is a harbinger of further decline in most subjects during a 7-year mean follow-up interval. Relevance for community populations should be investigated, and prevention studies in this at-risk population should be explored.

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    • "The current report addresses a knowledge gap about self-and informantreport of memory complaints and their relationship with objective memory performance and MTL volumes. Subjective memory complaints help to establish a decline in functioning relative to premorbid status, and existing evidence suggests that the presence of such complaints may be a harbinger of subsequent cognitive decline [5] [6] [7]. In addition, studies have reported similar MTL volumes (and *Corresponding author. "
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    ABSTRACT: The current study examined the relationship between subjective memory complaints (both self- and informant-report), objective memory performance, and medial temporal lobe (MTL) volume. MCI patients (n=58) and their informants (n=51) completed the Memory Assessment Clinics Self (MAC-S) and Family (MAC-F) rating scales as a measure of subjective memory. RBANS Immediate and Delayed Memory indices were used as objective measures of memory and a subset of MCI participants also underwent MRI, which was used to measure MTL volume. Patients reported greater difficulty with semantically based information (e.g., word and name recall) relative to informant report. However, the severity of these self-reports was unrelated to objective memory performance and only a single MAC-S scale was related to amygdalar volume. Conversely, several MAC-F indices were related to the RBANS Delayed Memory index as well as to amygdalar and hippocampal volumes. Measures of executive functioning were associated with MAC-S Frequency scales but not any MAC-F scale. The results of the current study suggest that, in those who are cognitively symptomatic, the frequency of self-reported subjective memory difficulty may reflect executive dysfunction but holds little value for verifying memory impairment. Conversely, informant report provides meaningful information about actual memory deficits in those with MCI.
    05/2015; 1(2). DOI:10.1016/j.dadm.2015.03.002
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    • "the subjects report specifically worsening of episodic memory function. Longitudinal studies have indicated that persons with SMI/SCD are at increased risk of AD [7] [8]. MRI studies have revealed structural volume reduction in medial temporal lobe regions in subjects with SMI in comparison to control subjects, which have been interpreted as signs of very early AD-related atrophy [9] [10] [11] [12]. "
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    ABSTRACT: Elderly individuals with subjective memory impairment (SMI) report memory decline, but perform within the age-, gender-, and education-adjusted normal range on neuropsychological tests. Longitudinal studies indicate SMI as a risk factor or early sign of Alzheimer's disease (AD). There is increasing evidence from neuroimaging that at the group level, subjects with SMI display evidence of AD-related pathology. This study aimed to determine differences in cortical thickness between individuals with SMI and healthy control subjects (CO) using the FreeSurfer environment. 110 participants (41 SMI/69 CO) underwent structural 3D-T1 MR imaging. Cortical thickness values were compared between groups in predefined AD-related brain regions of the medial temporal lobe, namely the bilateral entorhinal cortex and bilateral parahippocampal cortex. Cortical thickness reduction was observed in the SMI group compared to controls in the left entorhinal cortex (p = 0.012). We interpret our findings as evidence of early AD-related brain changes in persons with SMI.
    Journal of Alzheimer's disease: JAD 12/2014; 45(1). DOI:10.3233/JAD-142322 · 4.15 Impact Factor
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    • "E-mail address: memory decline [6], increased risk of AD [7] [8] [9], and have been associated with the presence of neurobiological markers of AD (e.g., grey matter atrophy [10] [11] [12] [13] [14], white matter integrity [15], amyloid burden [16] [17], and AD pathology at autopsy [18]). Although APOE ε4 has been associated with a greater prevalence of SCC [19] [20] [21], very limited research has addressed whether SCC predict memory decline in APOE ε4 carriers [22]. "
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    ABSTRACT: Background Subjective cognitive concerns may represent a simple method to assess likelihood of memory decline among apolipoprotein E (APOE) ε4 carriers. Methods We examined the relationship of self-reported subjective cognitive concerns, using seven specific cognitive concerns, with memory and memory decline over 6 years among APOE ε4 carriers and non-carriers from the Nurses' Health Study. Results In both groups, increasing subjective cognitive concern score predicted worse baseline memory and faster rates of subsequent memory decline, after adjustment for age, education and depression. The relation with baseline memory appeared statistically stronger in APOE ε4 carriers (P-interaction = 0.03). For memory decline, mean differences in slopes of episodic memory (95% CI) for 4 to 7 versus no concern = −0.05 (−0.10, 0.01) standard units in APOE ε4 carriers, and −0.04 (−0.08, −0.01) standard units in non-carriers. Conclusions APOE ε4 carriers with self-assessed cognitive concerns appear to have worse memory, and possibly accelerated memory decline.
    Alzheimer's and Dementia 09/2014; 10(6). DOI:10.1016/j.jalz.2014.06.012 · 12.41 Impact Factor
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