The rate of conversion of mild cognitive impairment to dementia: predictive role of depression

BACKGROUND: Mild cognitive impairment (MCI) is a condition referring to the persons with cognitive deficits measurable in some form or another, but not meeting criteria for dementia, and who have an increased risk of becoming demented. OBJECTIVE: To establish the rate of progression to dementia in MCI, to investigate the risk of conversion for amnestic vs multiple-domains subtypes, and to identify the predictors of progression. METHODS: MCI (n = 105) individuals enrolled in a longitudinal study received annual clinical and psychometric examinations for up to a mean of 3 years. The diagnosis of MCI according to Mayo Clinic Petersen's Criteria was conducted by a panel of specialists. RESULTS: After 3 years of follow-up, 23 of 105 subjects with MCI were diagnosed with dementia. 40 showed cognitive decline not dementia, 34 were stable and showed no cognitive decline or improvement, while eight showed cognitive improvement. CONCLUSIONS: We conclude that conversion rate from MCI to DSM-IIIR dementia was 21.9% over a period of 3 years. The occurrence of depressive symptoms may constitute a predictor for those who are more likely to progress to dementia. The risk of conversion to dementia was higher among the subjects with an evidence of impairment extending beyond memory than with those who suffered only from memory deficits, and the subjects who converted to dementia in this subtype had significantly higher baseline plasma total homocysteine levels than non-converters.     

Subjective cognitive function and decline among older adults with psychometrically defined amnestic MCI

OBJECTIVE: To examine the relationship between subjective cognitive function and subsequent cognitive decline among individuals with psychometrically defined amnestic mild cognitive impairment (MCI), and to determine whether the presence of depressive symptoms modifies this relationship. METHOD: Fifty-five individuals met psychometric criteria for amnestic mild cognitive impairment (MCI). Cognitive decline was measured using the Mini-Mental State Examination (MMSE), which was administered at baseline and at follow-up two years later. Subjective cognitive function was examined using two different one-item memory complaints, as well as a scale focused on current level of cognitive function relative to past function and a scale focused on forgetting in specific everyday situations. RESULTS: In multiple regression analyses, the one-item complaint of change in memory at baseline predicted future cognitive decline. There was a significant interaction effect whereby this association was stronger in participants who endorsed fewer symptoms of depression. CONCLUSION: Individuals showing memory deficits consistent with amnestic MCI have at least some insight regarding cognitive decline and the extent to which subjective cognitive function is useful in predicting future decline may depend on what particular questions are asked as well as presence of depressive symptoms.     

Homocysteine and cognitive decline in healthy elderly.

Serum homocysteine is increased, and correlates inversely with cognitive scores, in Alzheimer's disease (AD), vascular dementia and "age-associated memory impairment". Elevated levels might signal accelerated cognitive decline, although this remains to be established. We therefore repeated Mini-Mental State Examinations, together with additional ADAS-Cog assessments, in 32 healthy elderly individuals to determine whether prior homocysteine levels predicted cognitive changes over a 5-year period. Homocysteine predicted follow-up cognitive scores and rate of decline in cognitive performance independently of age, sex, education, renal function, vitamin B status, smoking and hypertension (p < 0.001). Homocysteine predicted word recall (p = 0.01), orientation (p = 0.02) and constructional praxis scores (p < 0.0001). One subject, with the second highest initial homocysteine, had developed probable AD at follow-up. Fasting total serum homocysteine appears to be an independent predictor of cognitive decline in healthy elderly and exerts a maximal effect on spatial copying skills.     

Subtype of mild cognitive impairment and progression to dementia and death

BACKGROUND: Mild cognitive impairment (MCI) represents a common cognitive state between normal cognitive aging and dementia. There is limited information about the heterogeneity of MCI and how this heterogeneity may influence the clinical course of MCI. We determined the longitudinal course of subtypes of MCI and assessed the rate of progression to dementia and to death. METHODS: As part of the Alzheimer's Disease Research Centers of California, we studied 327 patients with MCI (250 with amnestic MCI, 34 with single nonmemory MCI, and 43 with multiple domain MCI) who were followed longitudinally. We determined if subtype of MCI was independently associated with time to dementia diagnosis and time to death using Cox proportional hazard models, and type of dementia using Fisher's exact test. RESULTS: Mean age of the patients with MCI was 72.9 +/- 9.3 years and mean Mini-Mental State Examination score was 25.7 +/- 4.3. After a mean follow-up of 3.1 years, 199 (65%) progressed to dementia and 80 (24%) died. After multivariate adjustment, compared to those with amnestic MCI, patients with single nonmemory or multiple subtype MCI were less likely to receive a diagnosis of dementia (HR = 0.60; 95% CI 0.35-1.05 and HR = 0.71; 95% CI 0.44-1.14) but more likely to die (HR = 2.57; 95% CI 1.13-5.84 and HR = 1.73; 95% CI 0.72-4.18), but these results were of borderline statistical significance. There were significant differences in the type of dementia diagnosed across MCI subtypes (p = 0.006). Among the patients who progressed to Alzheimer's disease, 76% had prior amnestic MCI; of the patients who progressed to vascular dementia, 50% had prior amnestic MCI; all patients who progressed to a frontal dementia syndrome had single nonmemory MCI previously. CONCLUSIONS: The majority of patients with MCI progressed to dementia and a significant proportion died. Subtype of MCI may influence rates of progression to death and to dementia and has a major influence on subsequent type of dementia diagnosis.     

Mild cognitive impairment in a community sample: The Sydney Memory and Ageing Study

BackgroundMild cognitive impairment (MCI) is associated with an increased dementia risk. This study reports incidence of MCI subtypes, rates of progression to dementia, and stability of MCI classification.MethodsWe examined 873 community-dwelling adults aged 70 to 90 years over 2 years as part of an ongoing population-based longitudinal study, the Sydney Memory and Ageing Study. Neuropsychological testing assessed five cognitive domains, and a diagnosis of no cognitive impairment, MCI, or dementia (follow-up only) was made according to published criteria.ResultsThe incidence of MCI was 104.6 (95% confidence interval: 81.6–127.7) per 1000 person-years, with higher incidence in men (men, 156.8; women, 70.3). Incidence rates for single-domain amnestic, multiple-domain amnestic, single-domain nonamnestic, and multiple-domain nonamnestic MCI were 47.7, 7.9, 45.0, and 3.9 per 1000 person-years, respectively. The 2-year rate of progression from MCI at baseline to dementia was 4.8%, being highest for multidomain amnestic MCI (9.1%). Of those with MCI at baseline, 28.2% reverted to no cognitive impairment at follow-up. Sensitivity analyses by redefining criteria for cognitive impairment did not affect stability of diagnosis, although changing the threshold of domain impairment reduced baseline MCI prevalence from 36.7% to 5.7% and incidence to 23.5, and increased 2-year progression rate from MCI to dementia to 14.3%.ConclusionsIncidence rates for MCI are higher than previously reported, particularly in men and for single-domain MCI; rates for amnestic and nonamnestic MCI were comparable. Multidomain amnestic MCI was the most likely subtype to progress to dementia, but overall, the diagnosis of MCI, particularly single-domain MCI, shows considerable instability.     

Subtle memory decline over 12 months in mild cognitive impairment

OBJECTIVE: Screening of normal older persons for progressive memory decline is a worthwhile strategy in the pursuit of the earliest possible stages of pre-clinical Alzheimer's disease (AD) or mild cognitive impairment (MCI). Reliable tests are needed to both detect MCI and measure the natural history of decline over months rather than years. We aimed to detect memory decline over 1 year in a group of older individuals with well-characterised amnestic MCI. METHODS: The continuous learning task (CLT) from the CogState test battery was administered 8 times in 12 months to 15 individuals with MCI and 35 controls matched for age, education, IQ and gender. All subjects were recruited from an ongoing aging study. The rate of change in CLT performance over the year was compared between groups and also compared to that detected with a word list learning task and a computerised paired associate learning task. RESULTS: At baseline, memory performance in the amnestic MCI group was significantly worse than controls on all memory tests. However, at 12 months the magnitude of the difference between the groups had increased significantly on the CLT due to decline in memory accuracy in the MCI group. No decline over 12 months was detectable on the routine memory tests. CONCLUSIONS: Subtle memory decline is detectable in amnestic MCI using reliable and sensitive tests of memory. Such measures may assist in the early identification of AD and also in trials of putative disease-modifying therapies to be conducted over as little as 12 months.     

Conversion of amnestic Mild Cognitive Impairment to dementia of Alzheimer type is independent to memory deterioration

BACKGROUND: Mild Cognitive Impairment defines a transitional stage between normal ageing and dementia, and reflects the clinical situation where a person has memory complaints and objective evidence of cognitive impairment but no evidence of dementia. To plan the care of patients with MCI, it is important to predict as accurately as possible potential risk factors modulating the conversion to AD. AIM: To investigate the risk factors associated of conversion to dementia of Alzheimer type (AD) for subjects with amnestic Mild Cognitive Impairment (aMCI). METHODS AND MATERIALS: One hundred nineteen subjects consecutively recruited who met the operational criteria for aMCI (with or without deficits in other cognitive domains). They underwent multidimensional assessment and a neuropsychological battery at baseline and at follow-up, after 1 year. Diagnosis for dementia was based on a deficit in two or more cognitive domains severe enough to affect the participant functional abilities. Subjects converted to AD over time were classified as Demented; subjects that remained unchanged, or became cognitively normal during follow-up, were defined as Stable. RESULTS: Demented MCI (N = 40; 33.6%) were older (mean age 73.5 +/- 8.5 vs. 69.2 +/- 7.0; p = 0.006) when compared to Stable (N = 79; 66.4) and their global cognitive performances, at baseline, were more compromised when assessed by ADAS-Cog (mean score 10.7 +/- 3.9 vs 6.7 +/- 3.4; p = .000) and by MMSE (mean score 26.1 +/- 1.9 vs. 27.3 +/- 1.8; p = 0.002). Demented were similarly compromised in basic activities of daily living (BADL mean 0.2 +/- 0.4 vs 0.1 +/- 0.3 functions lost; p = NS) but more compromised on instrumental daily functions (IADL mean 0.7 +/- 0.8 vs. 0.1 +/- 0.5 functions lost; p = 0.001). The presence of white matter lesions (WML) on CT or MRI was more pronounced in Demented group (p = 0.02). After 1 year; Demented worsened on phonemic verbal fluency (PFL) (p = 0.009), Raven's coloured matrices (p = 0.003), Trail Making test A and B (p = 0.008 and p = 0.007 respectively) and in Instrumental Activities of Daily Living (IADL) (p =0 .000) respect to Stable. Logistic regression analysis revealed that ADAS-Cog basal score, Trail Making B, IADL but not memory deterioration were significantly associated to the conversion to AD. CONCLUSIONS: In subjects with aMCI poor global cognitive performance at baseline, the worsening on executive functions and on functional status but not the worsening on memory functions are independently associated with the conversion to dementia of Alzheimer type at 1 year, follow-up.     

Cerebrospinal fluid tau protein and periventricular white matter lesions in patients with mild cognitive impairment: implications for 2 major pathways

BACKGROUND: Mild cognitive impairment (MCI) may be a heterogeneous condition rather than a uniform disease entity. OBJECTIVE: To develop reliable tools that aid in identifying patients at risk of developing Alzheimer disease (AD) among heterogeneous populations with MCI to maximize the benefits of emerging therapies for AD. DESIGN: A 2-year prospective study. SETTING: Clinical follow-up in an outpatient memory clinic. PATIENTS: Seventy-two consecutive older patients with memory complaints. MAIN OUTCOME MEASURES: Cerebrospinal fluid tau levels, severity of periventricular and deep white matter lesions, silent brain infarction on magnetic resonance imaging, plasma homocysteine levels, apolipoprotein E genotype, and other vascular risk factors were assessed at baseline. RESULTS: Fifty-seven patients were diagnosed as having amnestic MCI. Forty-one patients with (AD-converted MCI group) or without (progressive MCI group) conversion to dementia and AD progressed over time, whereas the other 16 patients remained cognitively stable (stable MCI group). The stable MCI group was characterized by normal cerebrospinal fluid tau levels and a high grade of periventricular white matter lesions (PWMLs). The progressive MCI and AD-converted MCI groups had increased cerebrospinal fluid tau levels and low grades of PWMLs. A logistic regression model showed that age was significantly associated with developing PWMLs (P =.03; odds ratio, 1.15; 95% confidence interval, 1.0-1.3). CONCLUSIONS: Tau-related AD pathologic conditions and possibly ischemic PWMLs represent 2 major etiologies in the development of MCI, reflecting heterogeneity in the clinical progression. Because the progressive type of MCI may be a primary target of clinical trials that aim at secondary prevention of dementia, these patients should be identified by appropriate biomarkers and neuroimaging techniques.     

High rate of conversion to Alzheimer's disease in a cohort of amnestic MCI patients

BACKGROUND: A large proportion of patients with amnestic mild cognitive impairment (MCI) progress to Alzheimer's disease (AD), but the rate of conversion is highly variable, depending on selection and inclusion criteria. In the present prospective study, amnestic MCI criteria were applied in order to enrich the study population with prodromal AD patients. METHODS: A composite CERAD word list learning z-score of -1 was applied as a cut-off for memory performance at baseline. Competing causes of memory impairment other than prodromal AD were actively excluded. A cohort of 88 amnestic MCI patients was included; 75 were available for follow-up. RESULTS: After a mean delay of 19 months, 44% were found to have converted to AD, corresponding to an annualized conversion rate of 28%. The rate of new diagnoses other than stable MCI or AD was 6%. Baseline neuropsychological variables were not instrumental to predict progression. CONCLUSION: Amnestic MCI patients, as identified by the present set of criteria, carry a high risk of median-term progression to AD.     

Cognitive decline and amyloid accumulation in patients with mild cognitive impairment

Background/Aims: The relationship between baseline (11)C-Pittsburgh compound B ((11)C-PIB) uptake and cognitive decline during a 2-year follow-up was studied in 9 patients with mild cognitive impairment (MCI) who converted to Alzheimer's disease (AD) and 7 who remained with MCI. Methods: (11)C-PIB PET scan was conducted at baseline and cognitive assessment both at baseline and at follow-up. To obtain quantitative regional values of (11)C-PIB uptake, automated region of interest analysis was done using spatially normalized parametric ratio (region-to-cerebellar cortex) images. Results: At baseline, there were statistically significant differences in (11)C-PIB uptake, but not in cognitive test performances between the converters and nonconverters. Memory and executive function declined only in the converters during follow-up. In the converters, lower baseline frontal (11)C-PIB uptake was associated with faster decline in verbal learning. Higher baseline uptake in the caudate nucleus was related to faster decline in memory consolidation, and higher temporal uptake was associated with decline in executive function. Conclusion: Higher (11)C-PIB uptake in the caudate nucleus and temporal lobe was related to decline in memory and executive functions, whereas lower frontal uptake was related to decline in verbal learning. The results indicate that in prodromal AD, frontal amyloid accumulation reaches its maximum in the MCI stage, characterized by memory problems without full-blown dementia.     

Multiple cognitive deficits in amnestic mild cognitive impairment

OBJECTIVE: To determine if more widespread cognitive deficits are present in a narrowly defined group of patients with the amnestic form of mild cognitive impairment (MCI). METHODS: From a larger sample of patients clinically diagnosed as meeting the criteria of Petersen et al. for amnestic MCI, we selected 22 subjects who had Clinical Dementia Rating scores of zero on all domains besides memory and orientation. These MCI subjects with presumably isolated memory impairments were compared to 35 age-matched normal controls and 33 very mild Alzheimer's disease (AD) patients on a battery of neuropsychological tests. RESULT: In addition to the expected deficits in episodic memory, the amnestic MCI group performed less well than the controls but better than the AD group on design fluency, category fluency, a set shifting task and the Stroop interference condition. Over half the amnestic MCI group (vs. none of the normal controls) scored at least 1 standard deviation below control means on 4 or more of the nonmemory cognitive tasks. CONCLUSIONS: Isolated memory impairment may be fairly uncommon in clinically diagnosed amnestic MCI patients, even when the criteria for amnestic MCI are fairly narrow. Additional cognitive impairments are likely to include fluency and executive functioning. These more diffuse deficits argue for comprehensive cognitive assessments, even when the patient and family are reporting only memory decline, and are consistent with the increase in attention paid to the heterogeneity of MCI.     

Mild Behavioral Impairment as a Marker of Cognitive Decline in Cognitively Normal Older Adults

ObjectiveMild behavioral impairment (MBI) is a neurobehavioral syndrome characterized by later life emergent neuropsychiatric symptoms (NPS) that represent an at-risk state for incident cognitive decline and dementia in people with mild cognitive impairment (MCI). We undertook a study to determine whether MBI was associated with progressive changes in neuropsychological performance in people without significant cognitive impairment.MethodsA total of 9,931 older adults enrolled in the PROTECT study who did not have MCI or dementia undertook a comprehensive neuropsychological battery measuring attention, reasoning, executive function, and working memory at baseline and 1 year. MBI was ascertained using self-administration of the Mild Behavioral Impairment Checklist at 1 year, and participants were grouped according to MBI status: No Symptoms, Intermediate NPS and MBI. All assessments were completed online, and data analyzed using mixed-effects model repeated measures analysis of covariance.ResultsA total of 949 (10%) people had MBI. These individuals had significantly worse cognitive performance at baseline and significantly greater decline over 1 year in the four composite cognitive scores measuring attentional intensity (F [2,8578] = 3.97; p = 0.019), sustained attention (F [2,8578] = 18.63; p <0.0001), attentional fluctuation (F [2,8578] = 10.13; p <0.0001) and working memory (F [2,9895] = 13.1; p <0.0001).ConclusionOur novel findings show that MBI is associated with faster decline in attention and working memory in this cognitively normal sample. MBI may be an earlier marker of neurodegenerative disease than MCI, captured at the stage of subjective cognitive decline or before, raising the possibility that MBI represents a novel target for dementia clinical trials or prevention strategies.     

An investigation of PreMCI: subtypes and longitudinal outcomes

Background/AimsTo investigate the clinical features and rates of progression of conditions that are not considered to be normal, but do not fulfill criteria for mild cognitive impairment (MCI).MethodsWe longitudinally evaluated 269 elderly subjects who did not meet formal criteria for MCI at baseline but had: (1) a clinical history suggesting MCI without neuropsychological deficits (PreMCI-Clinical); or (2) neuropsychological deficits on one or more memory measures in conjunction with a negative clinical examination (amnestic PreMCI-NP) or were normal on both neuropsychological and clinical examination.ResultsThe rate of progression to MCI or dementia over an average of 2- to 3 years was 3.7% for no cognitive impairment subjects, whereas it was significantly greater for all PreMCI subtypes (22.0% for PreMCI-Clinical, 38.9% for amnestic PreMCI-NP subjects with two or more memory impairments). Among PreMCI subjects as a whole, lower baseline scores on object memory and category fluency tests were the best predictors of progression to MCI or dementia. Cardiovascular risk factors, Parkinsonian symptoms, and hippocampal atrophy were not associated with progression.ConclusionDistinct PreMCI subtypes defined on the basis of clinical and neuropsychological evaluations were found to have distinct characteristics, but both subtypes demonstrated elevated risk for progression to MCI or dementia. Despite the lack of evidence of clinical impairment, subjects with neuropsychological deficits in two memory domains were particularly at increased risk for progression of their deficits.     

Subjective memory complaints in Chinese subjects with mild cognitive impairment and early Alzheimer's disease

BACKGROUND: Mild cognitive impairment (MCI) represents a transitional state between normal aging and dementia. However, there is inconsistent opinion as to the validity of subjective memory complaints as a criterion for diagnosis. OBJECTIVE: This study aimed to examine the potential significance of applying a short memory questionnaire in the assessment of Chinese subjects with MCI and early dementia. METHODS: Three hundred and six ambulatory Chinese subjects were recruited. Each participant completed a short memory questionnaire. They were also assessed with the Chinese versions of the mini-mental state examination (CMMSE), Alzheimer's disease assessment scale-cognitive subscale (ADAS-Cog), category verbal fluency test (CVFT) and span tests. Severity of cognitive impairment was evaluated using the Clinical Dementia Rating (CDR); subjects with CDR 0.5 were further classified into MCI not demented (MCIND) and MCI possible incipient dementia (MCIID) depending on the subscale scores of CDR. RESULTS: An increasing frequency of memory complaints with increasing CDR was observed (Kruskal Wallis test, chi square = 21.29, df 3, p < 0.001). With a cutoff of 3 or more memory complaints, the memory questionnaire demonstrated a sensitivity of 65.3% and 70.4% in identifying subjects with incipient and early dementia respectively. Significant associations between memory complaints and most cognitive test performance were found (Spearman's correlations, p < 0.01). Logistic regression analysis revealed that educational level, the memory questionnaire, ADAS-Cog total and delayed recall scores were significant predictors of MCIID status. CONCLUSIONS: The findings suggested that a short memory questionnaire is useful in the screening of MCI, particularly in subjects who already present with subtle functioning disturbances. Subjective memory complaints were significant correlated with objective performance of memory functions, reflecting the usefulness of memory complaints in the assessment of MCI.     

Predictive validity and diagnostic stability of mild cognitive impairment subtypes

BackgroundMild cognitive impairment (MCI) is subclassified into four subtypes by the presence of impairment in the memory domain (amnestic vs nonamnestic) and the number of impaired cognitive domains (single vs multiple). However, predictive validity for outcomes of these criteria and the diagnostic stability of the subtypes are questionable.MethodsWe investigated the outcomes of 140 patients with MCI who participated in the baseline study of the Korean Longitudinal Study on Health and Aging and completed the 18-month follow-up evaluation (mean duration of follow-up = 1.57 ± 0.24 years). We evaluated the predictive validity of the criteria using multinomial logistic regression analyses, and the diagnostic stability of MCI subtypes using annual conversion rates between subtypes.ResultsCompared with the single-domain type (MCIs), the multiple-domain type (MCIm) had a lower chance of reversion to normal cognition (MCIm = 10.94%, MCIs = 43.42%) and higher risk of conversion to dementia (MCIm = 23.44%, MCIs = 5.26%). The difference in the reversion rate between the multiple- and single-domain type was statistically significant (odds ratio = 0.233, 95% confidence interval = 0.070–0.771, P = .017). However, neither the chance of reversion nor the risk of conversion was different between amnestic and nonamnestic subtypes. Among the 81 participants who neither converted to dementia nor reverted to normal cognition, 39 converted to different subtype (annual conversion rate = 17.74%).ConclusionsThe number of impaired cognitive domains, but not the presence of memory impairment, predicted poor outcomes in people with MCI. However, MCI subtype was diagnostically unstable.     

FDG-PET measurement is more accurate than neuropsychological assessments to predict global cognitive deterioration in patients with mild cognitive impairment

The accurate prediction, at a pre-dementia stage of Alzheimer's disease (AD), of the subsequent clinical evolution of patients would be a major breakthrough from both therapeutic and research standpoints. Amnestic mild cognitive impairment (MCI) is presently the most common reference to address the pre-dementia stage of AD. However, previous longitudinal studies on patients with MCI assessing neuropsychological and PET markers of future conversion to AD are sparse and yield discrepant findings, while a comprehensive comparison of the relative accuracy of these two categories of measure is still lacking. In the present study, we assessed the global cognitive decline as measured by the Mattis scale in 18 patients with amnestic MCI over an 18-month follow-up period, studying which subtest of this scale showed significant deterioration over time. Using baseline measurements from neuropsychological evaluation of memory and PET, we then assessed significant markers of global cognitive change, that is, percent annual change in the Mattis scale total score, and searched for the best predictor of this global cognitive decline. Altogether, our results revealed significant decline over the 18-month follow-up period in the total score and the verbal initiation and memory-recall subscores of the Mattis scale. The percent annual change in the total Mattis score significantly correlated with age and baseline performances in delayed episodic memory recall as well as semantic autobiographical and category word fluencies. Regarding functional imaging, significant correlations were also found with baseline PET values in the right temporo-parietal and medial frontal areas. Age and right temporo-parietal PET values were the most significant predictors of subsequent global cognitive decline, and the only ones to survive stepwise regression analyses. Our findings are consistent with previous works showing predominant delayed recall and semantic memory impairment at a pre-dementia stage of AD, as well as early metabolic defects in the temporo-parietal associative cortex. However, they suggest that only the latter predictor is specifically and accurately associated with subsequent cognitive decline in patients with MCI within 18 months of first assessment.     

A behavioral rehabilitation intervention for amnestic mild cognitive impairment

Individuals with amnestic mild cognitive impairment (MCI) currently have few treatment options for combating their memory loss. The Memory Support System (MSS) is a calendar and organization system with accompanying 6-week curriculum designed for individuals with progressive memory impairment. Ability to learn the MSS and its utility were assessed in 20 participants. Participants were significantly more likely to successfully use the calendar system after training. Ninety-five percent were compliant with the MSS at training completion, and 89% continued to be compliant at follow-up. Outcome measures revealed a medium effect size for improvement in functional ability. Subjects further reported improved independence, self-confidence, and mood. This initial examination of the MSS suggests that with appropriate training, individuals with amnestic MCI can and will use a memory notebook system to help compensate for memory loss. These results are encouraging that the MSS may help with the symptoms of memory decline in MCI.     

Hypertension and the risk of mild cognitive impairment

OBJECTIVE: To explore whether hypertension is associated with the risk of mild cognitive impairment (MCI), an intermediate stage of dementia, because there are conflicting data relating hypertension to the risk of Alzheimer disease. DESIGN AND SETTING: Prospective community-based cohort study conducted in northern Manhattan. Multivariate proportional hazards regression analyses were used, relating hypertension to incident all-cause MCI, amnestic MCI, and nonamnestic MCI in 918 persons without prevalent MCI at baseline followed up for a mean of 4.7 years. RESULTS: There were 334 cases of incident MCI, 160 cases of amnestic MCI, and 174 cases of nonamnestic MCI during 4337 person-years of follow-up. Hypertension was associated with an increased risk of all-cause MCI (hazard ratio, 1.40; 95% confidence interval, 1.06-1.77; P = .02) and nonamnestic MCI (hazard ratio, 1.70; 95% confidence interval, 1.13-2.42; P = .009) after adjusting for age and sex. Both associations were slightly attenuated in models additionally adjusting for stroke and other vascular risk factors. There was no association between hypertension and the risk of amnestic MCI (hazard ratio, 1.10; 95% confidence interval, 0.79-1.63; P = .49). Consistent with this association, hypertension was related with the slope of change in an executive ability score, but not with memory or language score. There was no effect modification of the association between hypertension and MCI by APOEepsilon4 genotype or use of antihypertensive medication. CONCLUSIONS: A history of hypertension is related to a higher risk of MCI. The association seems to be stronger with the nonamnestic than the amnestic type of MCI in the elderly. These findings suggest that prevention and treatment of hypertension may have an important impact in lowering the risk of cognitive impairment.     

MRI measures and progression of cognitive decline in nondemented elderly attending a memory clinic

OBJECTIVE: To investigate whether MRI-based volumes of whole brain, medial temporal lobe and white matter hyperintensities (WMH) predict progression of cognitive decline in a sample of nondemented elderly. METHODS: Thirty-seven nondemented elderly attending a memory clinic and 28 elderly controls participated in this follow-up study. The average follow-up period was 1.8 years. Cognitive function was measured at baseline and follow-up with the Cambridge Cognitive Examination (CAMCOG). Baseline Magnetic Resonance Imaging (MRI) provided quantitative measures of whole brain, medial temporal lobe and WMH. Linear mixed models controlled for age and sex were used to assess the independent associations between MRI measures, baseline cognition, and annual decline in cognition. RESULTS: Medial temporal lobe volume was independently associated with baseline CAMCOG score (p < 0.01), whereas whole brain volume (p < 0.01) and WMH (p < 0.05) were associated with annual decline in CAMCOG score. CONCLUSIONS: These data suggest that regional damage to the medial temporal lobes underlies initial mild cognitive impairment, whereas more global brain changes, such as whole brain atrophy and WMH, contribute to further progression of cognitive decline.     

Plasma ceramides are altered in mild cognitive impairment and predict cognitive decline and hippocampal volume loss

BackgroundA blood-based biomarker of Alzheimer's disease (AD) would be superior to cerebrospinal fluid (CSF) and neuroimaging measures in terms of cost, invasiveness, and feasibility for repeated measures. We previously reported that blood ceramides varied in relation to timing of memory impairment in a population-based study. The present objective was to examine whether plasma ceramides varied by AD severity in a well-characterized clinic sample and were associated with cognitive decline and hippocampal volume loss over 1 year.MethodsParticipants included 25 normal controls (NC), 17 amnestic Mild Cognitive Impairment (MCI), and 21 early probable AD. A thorough neuropsychological battery and neuroimaging with hippocampal volume determination were conducted at baseline and 1 year later. Plasma ceramides were assayed at baseline using high performance liquid chromatography coupled electrospray ionization tandem mass spectrometry.ResultsAlthough all saturated ceramides were lower in MCI compared with AD at baseline, ceramides C22:0 and C24:0 were significantly lower in the MCI group compared with both NC and AD groups (P < .01). Ceramide levels did not differ (P > .05) in AD versus NC. There were no cross-sectional associations between ceramides C22:0 and C24:0 and either cognitive performance or hippocampal volume among any group. However, among the MCI group, higher baseline ceramide C22:0 and C24:0 levels were predictive of cognitive decline and hippocampal volume loss 1 year later.ConclusionResults suggest that very long-chain plasma ceramides C22:0 and C24:0 are altered in MCI and predict memory loss and right hippocampal volume loss among subjects with MCI. These plasma ceramides may be early indicators of AD progression.