Faculty Bibliography

Descriptions of dementia can be traced to antiquity. Prichard (1837) described four dementia stages and Kral (1962) described a 'benign senescent forgetfulness' condition. The American Psychiatric Association's DSM-III (1980) identified an early dementia stage.In 1982, the Clinical Dementia Rating (CDR) and the Global Deterioration Scale (GDS) were published, which identified dementia antecedents. The CDR 0.5 'questionable dementia' stage encompasses both mild dementia and earlier antecedents. GDS stage 3 described a predementia condition termed 'mild cognitive decline' or, alternatively, beginning in 1988, 'mild cognitive impairment' (MCI). This GDS stage 3 MCI condition is differentiated from both a preceding GDS stage 2, 'subjective cognitive impairment' (SCI) stage and a subsequent GDS 4 stage of mild dementia.GDS stage 3 MCI has been well characterized. For example, specific clinical concomitants, mental status and psychological assessment score ranges, behavioral and emotional changes, neuroimaging concomitants, neurological reflex changes, electrophysiological changes, motor and coordination changes, and changes in activities, accompanying GDS stage 3 MCI have been described.Petersen and associates proposed a definition of MCI in 2001 which has been widely used (hereafter referred to as 'Petersen's MCI'). Important differences between GDS stage 3 MCI and Petersen's MCI are that, because of denial, GDS stage 3 MCI does not require memory complaints. Also, GDS stage 3 MCI recognizes the occurrence of executive level functional deficits, which Petersen's MCI did not. Nevertheless, longitudinal and other studies indicate essential compatibility between GDS stage 3 MCI and Petersen's MCI duration and outcomes

The aim of the study was to compare the performance of Robust and Conventional neuropsychological norms in predicting clinical decline among healthy adults and in mild cognitive impairment (MCI). The authors developed Robust baseline cross sectional and longitudinal change norms from 113 healthy participants retaining a normal diagnosis for at least 4 years. Baseline Conventional norms were separately created for 256 similar healthy participants without follow-up. Conventional and Robust norms were tested in an independent cohort of longitudinally studied healthy (n=223), MCI (n=136), and Alzheimer's disease (AD, n=162) participants; 84 healthy participants declined to MCI or AD (NL-->DEC), and 44 MCI declined to AD (MCI-->AD). Compared to Conventional norms, baseline Robust norms correctly identified a higher proportion of NL-->DEC with impairment in delayed memory and attention-language domains. Both norms predicted decline from MCI-->AD. Change norms for delayed memory and attention-language significantly incremented baseline classification accuracies. These findings indicate that Robust norms improve identification of healthy individuals who will decline and may be useful for selecting at-risk participants for research studies and early interventions

BACKGROUND: Subjective cognitive impairment (SCI) has been a common, but poorly understood condition, frequently occurring in older persons. METHODS: The past and the emerging literature on SCI and synonymously named conditions is reviewed. RESULTS: Findings include: (1) There is support from at least one longitudinal study for a long-standing concept of SCI as a pre-mild cognitive impairment (MCI) condition lasting approximately 15years. (2) There are complex relationships between SCI and depression and anxiety. (3) Differences in SCI subjects from age-matched non-SCI persons are being published in terms of cognitive tests, hippocampal gray matter density, hippocampal volumes, cerebral metabolism, and urinary cortisol levels. Psychometric and dementia test score differences between SCI and MCI subjects have long been evident. (4) Predictive electrophysiologic features of subsequent decline in SCI subjects are being published. CONCLUSIONS: Studies of therapeutic agents in SCI treatment and resultant Alzheimer's disease prevention appear to be feasible. These trials are also necessary from a public health perspective

BACKGROUND/AIMS: Previously we have shown that functional declines in Parkinson's disease (PD) and Alzheimer's disease (AD) correlate to global measures of cognitive decline. We now determine if the correlation between cognitive impairment and functional ability in PD is similar to that in AD using individual cognitive measures. METHODS: 93 PD subjects and 124 AD/MCI subjects underwent the Functional Assessment Staging (FAST), the Global Deterioration Scale (GDS), and a neuropsychological battery. RESULTS: In PD subjects, the FAST and GDS correlated significantly with Rey Auditory Verbal Learning Test (AVLT), Controlled Oral Word Association (COWA), Animal Fluency, and Stroop but not with Clock Draw or Judgment Line Orientation (JLO). In AD/MCI subjects, FAST and GDS correlated with all neuropsychological components except Stroop. In the AD/MCI group, the UPDRS significantly correlated with the FAST, GDS, MMSE, and all neuropsychological parameters except the Stroop. In the PD group, the motor UPDRS significantly correlated significantly with FAST, GDS, MMSE and all neuropsychological parameters except Digit Span, Stroop, Clock Draw and JLO. CONCLUSIONS: Similar to AD, functional decline in PD correlates with multiple measures of cognitive impairment. Some differences between PD and AD may be explained by the influence of motor disability and declines in visuospatial function in PD.

Amyloid beta (Abeta) immunoreactivity in neurons was examined in brains of 32 control subjects, 31 people with Down syndrome, and 36 patients with sporadic Alzheimer's disease to determine if intraneuronal Abeta immunoreactivity is an early manifestation of Alzheimer-type pathology leading to fibrillar plaque formation and/or neurofibrillary degeneration. The appearance of Abeta immunoreactivity in neurons in infants and stable neuron-type specific Abeta immunoreactivity in a majority of brain structures during late childhood, adulthood, and normal aging does not support this hypothesis. The absence or detection of only traces of reaction with antibodies against 4-13 aa and 8-17 aa of Abeta in neurons indicated that intraneuronal Abeta was mainly a product of alpha- and gamma-secretases (Abeta(17-40/42)). The presence of N-terminally truncated Abeta(17-40) and Abeta(17-42) in the control brains was confirmed by Western blotting and the identity of Abeta(17-40) was confirmed by mass spectrometry. The prevalence of products of alpha- and gamma -secretases in neurons and beta- and gamma-secretases in plaques argues against major contribution of Abeta-immunopositive material detected in neuronal soma to amyloid deposit in plaques. The strongest intraneuronal Abeta(17-42) immunoreactivity was observed in structures with low susceptibility to fibrillar Abeta deposition, neurofibrillary degeneration, and neuronal loss compared to areas more vulnerable to Alzheimer-type pathology. These observations indicate that the intraneuronal Abeta immunoreactivity detected in this study is not a predictor of brain amyloidosis or neurofibrillary degeneration. The constant level of Abeta immunoreactivity in structures free from neuronal pathology during essentially the entire life span suggests that intraneuronal amino-terminally truncated Abeta represents a product of normal neuronal metabolism

Background/Aims: Subjective memory complaint (SMC) in normal individuals may predict future cognitive decline. The goal of this study was to examine whether the probability of decline increases with growing intensity of complaint. Methods: Normal subjects over the age of 50 years were included in a longitudinal retrospective study (mean follow-up time = 8 years). All subjects (n = 230) underwent cognitive and medical examination at baseline. The presence of SMC was determined based on Global Deterioration Scale staging. A subgroup of 83 participants also received baseline assessment for the intensity of SMC. Logistic regression was used to predict outcome from baseline variables. Three outcome groups were established at the final visit: nondeclining, declining and diagnostically unstable (i.e. the diagnosis changed over time: from normal to mild cognitive impairment, then back to normal). Results: The presence of SMC was a predictor of future decline but also increased the likelihood of the unstable diagnosis. Increasing intensity of SMC did not further raise the risk for decline. High intensity of complaints and more pronounced affective symptoms predicted the unstable clinical diagnosis. Conclusions: The presence of SMC contributes to the risk of future decline, however, the increasing intensity of the perceived impairment does not further enhance the risk.

Global measures used in treatment trials in dementia encompass two distinct categories: (1) clinician's interview-based global severity scales, and (2) clinician's interview-based global change scales. The global severity scales that have been used include: the Clinical Dementia Rating (CDR) and the related CDR-sum of boxes (CDR-SB), the Global Deterioration Scale (GDS), and the Functional Assessment Staging (FAST) procedure. The global severity scales are clearly useful in subject categorization in treatment trials, in part because they are relatively free of many of the sociocultural biases inherent in mental status and psychometric descriptors. Global severity scales can also be used to demonstrate therapeutic efficacy in terms of the general progression of the dementia process. These measures have also proven to be useful in sensitively assessing pharmacotherapeutic effects in Alzheimer's disease (AD) treatment trials. For example, in pivotal trials: (1) in Mild to Moderate AD, the GDS has shown significant change in response to medication, whereas the results on the Mini-mental State Examination (MMSE) were not significant, and (2) in Moderate to Severe AD, the FAST has shown significant pharmacotherapeutic efficacy, whereas the results using the MMSE were not significant. The global change scales employed in dementia trials differ widely in assessment methodology. Clinical Global Impressions of Change (CGIC) scales do not have defined methodologies, whereas Clinician's Interview-Based Impression of Change Plus Caregiver Input (CIBIC-Plus) scales are much more elaborate. The CIBIC-Plus procedures require an independent clinician assessment and can provide independent, comprehensive evidence of therapeutic efficacy. The CIBIC-Plus procedure may also be useful in sensitively assessing efficacy in future prevention trials, for example in subjects with Subjective Cognitive Impairment. For Mild Cognitive Impairment (MCI), global severity scales already appear to be one modality for the sensitive assessment of change. The CIBIC-Plus procedures might also productively be applied in future MCI therapeutic trials

BACKGROUND: This study is an extension of a 28-week, randomized, double-blind, placebo-controlled study of memantine in 252 patients with moderate to severe Alzheimer disease. OBJECTIVE: To evaluate long-term memantine treatment in moderate to severe Alzheimer disease. DESIGN, SETTING, AND PATIENTS: Open-label, 24-week extension trial. Raters remained blind to the patients' initial study treatment. Patients (n = 175) were enrolled from the previous double-blind study in an outpatient setting. INTERVENTION: Twenty mg of memantine was given daily. MAIN OUTCOME MEASURES: Efficacy assessments from the double-blind study were continued and safety parameters were monitored. RESULTS: Patients who switched to memantine treatment from their previous placebo therapy experienced a significant benefit in all main efficacy assessments (functional, global, and cognitive) relative to their mean rate of decline with placebo treatment during the double-blind period (P<.05). The completion rate for the extension phase of the study was high (78%) and the favorable adverse event profile for memantine therapy was similar to that seen in the double-blind study. CONCLUSION: These results extend previous findings that demonstrated the efficacy and safety of memantine in the treatment of patients with moderate to severe Alzheimer disease

The diagnosis of Alzheimer's disease (AD) in patients with mild cognitive impairment (MCI) is limited because it is based on non-specific behavioral and neuroimaging findings. The lesions of Alzheimer's disease: amyloid beta (Abeta) deposits, tau pathology and cellular oxidative damage, affect the hippocampus in the earlier stages causing memory impairment. In a 2-year longitudinal study of MCI patients and normal controls, we examined the hypothesis that cerebrospinal fluid (CSF) markers for these pathological features improve the diagnostic accuracy over memory and magnetic resonance imaging (MRI)-hippocampal volume evaluations. Relative to control, MCI patients showed decreased memory and hippocampal volumes and elevated CSF levels of hyperphosphorylated tau and isoprostane. These two CSF measures consistently improved the diagnostic accuracy over the memory measures and the isoprostane measure incremented the accuracy of the hippocampal volume achieving overall diagnostic accuracies of about 90%. Among MCI patients, over 2 years, longitudinal hippocampal volume losses were closely associated with increasing hyperphosphorylated tau and decreasing amyloid beta-42 levels. These results demonstrate that CSF biomarkers for AD contribute to the characterization of MCI