Distribution of APOE genotypes in a memory clinic cohort

Impact of Shift Work and Long Working Hours on Worker Cognitive Functions: Current Evidence and Future Research Needs

Particular working conditions and/or organization of working time may cause important sleep disturbances that have been proposed to be predictive of cognitive decline. In this regard, circadian rhythm misalignment induced by exposure to night work or long working hours would be responsible for cognitive impairment. Nevertheless, evidence supporting this correlation is limited and several issues still need to be elucidated. In this regard, we conducted a systematic review to evaluate the association between shift/night work and cognitive impairment and address its main determinants. Information provided by the reviewed studies suggested that night work might have serious immediate negative effects especially on cognitive domains related to attention, memory and response inhibition. Furthermore, cognitive performance would progressively worsen over consecutive night shifts or following exposure to very long work shifts. Otherwise, conflicting results emerged regarding the possible etiological role that night work chronic exposure would have on cognitive impairment. Therefore, circadian rhythm desynchronization, lack of sleep and fatigue resulting from night work may negatively impact worker’s cognitive efficiency. However, in light of the considerable methodological variability of the reviewed studies, we proposed to develop a standardized research and evaluation strategy in order to obtain a better and comprehensive understanding of this topic.

Distribution and clinical impact of apolipoprotein E4 in subjective memory impairment and early mild cognitive impairment

The apolipoprotein E (APOE) e4 allele is the most common genetic variant associated with Alzheimer’s disease (AD). We sought to investigate the distribution of APOE genotypes across the full clinical AD spectrum including AD, late-stage amnestic mild cognitive impairment (L-aMCI), early-stage aMCI (E-aMCI), subjective memory impairment (SMI), and controls. We prospectively recruited 713 AD patients, 735 aMCI patients, 575 SMI patients, and 8,260 individuals as controls. The frequency of the APOE e4 allele revealed an ordered fashion in the AD (30.8%), L-aMCI (24.0%), E-aMCI (15.1%), SMI (11.7%), and control (9.1%) groups. APOE e3/e4 and e4/e4 genotype frequencies also appeared in an ordered fashion in the AD group (39.1% of e3/e4 and 10.9% of e4/e4), as well as the L-aMCI (28.3% and 9.4%), E-aMCI (22.3% and 3.7%), SMI (18.3% and 1.9%), and control (15.1% and 0.8%) groups. In the comparisons of APOE e3/e3 vs. e3/e4 genotypes, all patient groups had a higher frequency of APOE e3/e4 relative to the control group. Relative to the SMI and E-aMCI groups, the AD and L-aMCI groups had higher frequency of the APOE e3/e4 genotype, and the AD group had a higher frequency relative to the L-aMCI group. However, there was no significant difference between the E-aMCI and SMI groups. In our longitudinal data, APOE e4 carrier showed a steeper incline slope in a clinical dementia rating sum of boxes (CDR-SB) score than APOE e4 non-carrier in SMI (B = 0.0066, p = 0.0104), E-aMCI (B = 0.0313, p < 0.0001), and L-aMCI (B = 0.0178, p = 0.0007). APOE e4 carrier showed a steeper decline slope in the CDR-SB than APOE e4 non-carrier in AD (B = − 0.0309, p = 0.0003). These findings suggest that E-aMCI and SMI are associated with a similarly increased frequency of the APOE e4 allele compared to controls, suggesting a greater genetic risk for AD and the importance of monitoring the allele more closely.

Influence of apolipoprotein-E genotype on brain amyloid load and longitudinal trajectories

To characterize the influence of apolipoprotein-E (APOE) genotype on cerebral Aβ load and longitudinal Aβ trajectories, [¹¹C]Pittsburgh compound-B (PiB) positron emission tomography (PET) imaging was used to assess amyloid load in a clinically heterogeneous cohort of 428 elderly participants with known APOE genotype. Serial [¹¹C]PiB data and a repeated measures model were used to model amyloid trajectories in a subset of 235 participants classified on the basis of APOE genotype. We found that APOE-ε4 was associated with increased Aβ burden and an earlier age of onset of Aβ positivity, whereas APOE-ε2 appeared to have modest protective effects against Aβ. APOE class did not predict rates of Aβ accumulation. The present study suggests that APOE modifies Alzheimer's disease risk through a direct influence on amyloidogenic processes, which manifests as an earlier age of onset of Aβ positivity, although it is likely that other genetic, environmental, and lifestyle factors are important.

Motoric cognitive risk syndrome: Integration of two early harbingers of dementia in older adults

Dementia is characterized by a long preclinical phase that may last years to decades before the onset of mild cognitive impairment. Slow gait speed and subjective memory complaint commonly co-occur during this preclinical phase, and each is a strong independent predictor of cognitive decline and dementia. Motoric cognitive risk (MCR) syndrome is a pre-dementia syndrome that combines these two early harbingers of dementia. The risk of cognitive decline or dementia is stronger for MCR than for either slow gait speed or subjective memory complaint alone. Slow gait speed and subjective memory complaint have several common risk factors: cardiovascular disease, diabetes mellitus, abnormal cortisol profiles, low vitamin D levels, brain atrophy with decreased hippocampal volume, and increased deposition of beta-amyloid in the brain. The underlying pathogenesis of MCR remains poorly understood. Metabolomics and proteomics have great potential to provide new insights into biological pathways involved in MCR during the long preclinical phase preceding dementia.

Dysfunction of Inferior Parietal Lobule During Sensory Gating in Patients With Amnestic Mild Cognitive Impairment

Patients with amnestic mild cognitive impairment (aMCI) demonstrate significant cognitive deficits, especially in the memory aspect. The memory deficiency might be attributed to the difficulties in the inhibitory function to suppress redundant stimuli. Sensory gating (SG) refers to the attenuation of neural responses to the second identical stimulus in a paired-click paradigm, in which auditory stimuli are delivered in pairs with inter-stimulus intervals (ISI) of 500 ms and inter-pair intervals of 6-8 s. It is considered as an electrophysiological signal to reflect the brain's automatic response to gate out repetitive sensory inputs. However, there has been no study systematically investigating SG function in aMCI patients. Thus, the present study used magnetoencephalography (MEG) to record neuromagnetic responses to a paired-click paradigm in 23 healthy controls (HC) and 26 aMCI patients. The Stimulus 2/Stimulus 1 (S2/S1) amplitude ratio was used to represent the SG function. Compared to HC, aMCI patients showed M50 SG deficits in the left inferior frontal gyrus (IFG) and right inferior parietal lobule (IPL). M100 SG defects were also observed in the right IPL. Based on the ROIs showing significant between-group SG differences, we found that a more deficient M50 SG function in the right IPL was associated with poorer performance in the immediate recall of Logic Memory (LM), Chinese Version Verbal Learning Test (CVVLT) and Digit Span Backward (DSB) Test. Furthermore, the M50 SG ratios of the right IPL together with the neuropsychological performance of LM and CVVLT demonstrated very good accuracy in the discrimination of aMCI from HC. In conclusion, compared to HC, aMCI patients showed a significant SG deficit in the right IPL, which was correlated with the auditory short-term memory function. We suggest the combination of SG in the right IPL, LM and CVVLT to be sensitive indicators to differentiate aMCI patients from HC.

Impact of Recruitment Methods in Subjective Cognitive Decline

BACKGROUND

Recruitment methods can determine sample characteristics in mild cognitive impairment and Alzheimer's disease dementia, but little is known about its influence in subjective cognitive decline (SCD).

OBJECTIVE

To determine the influence of two types of recruitment methods in the characteristics of individuals with SCD.

METHODS

We select and compare clinical and neuropsychological features, and frequency of APOE ɛ4 allele of 326 subjects with SCD from two cohorts: Open House Initiative (OHI) versus Memory Unit (MU). A logistic regression analysis (LRA), using gender and years of education as covariates, was used to examine the neuropsychological variables.

RESULTS

The OHI sample were mostly women (75.9% versus 64.5%, p < 0.05), with higher educational level (12.15 [3.71] versus 10.70 [3.80] years, p = 0.001), and more family history of dementia (138 [62.7%] versus 44 [41.5%], p < 0.001) than the MU sample. Also, the OHI sample showed better overall neuropsychological performance than the MU sample, and after a LRA, this trend continued in automatic response inhibition capacity, abstract reasoning, and recognition memory. We did not find differences in age, depression history, and/or APOE ɛ4 allele frequency.

CONCLUSION

SCD subjects showed different demographic and neuropsychological characteristics depending on the recruitment method, which should be taken into account in the design of research studies with this target population.

Amsterdam Dementia Cohort: Performing Research to Optimize Care

The Alzheimer center of the VU University Medical Center opened in 2000 and was initiated to combine both patient care and research. Together, to date, all patients forming the Amsterdam Dementia Cohort number almost 6,000 individuals. In this cohort profile, we provide an overview of the results produced based on the Amsterdam Dementia Cohort. We describe the main results over the years in each of these research lines: 1) early diagnosis, 2) heterogeneity, and 3) vascular factors. Among the most important research efforts that have also impacted patients' lives and/or the research field, we count the development of novel, easy to use diagnostic measures such as visual rating scales for MRI and the Amsterdam IADL Questionnaire, insight in different subgroups of AD, and findings on incidence and clinical sequelae of microbleeds. Finally, we describe in the outlook how our research endeavors have improved the lives of our patients.

Apolipoprotein E e4 Allele Is Associated with Subjective Cognitive Decline: A Meta-Analysis

BACKGROUND AND PURPOSE

Subjective cognitive decline (SCD) is a condition associated with increased risk of Alzheimer's disease. This study performs a meta-analysis to estimate the prevalence of the Apolipoprotein E e4 (APOE e4) allele in SCD and the association of APOE e4 with SCD.

METHODS

The MEDLINE, EMBASE, and Cochrane Library databases were searched. Meta-analyses were conducted using STATA 12.0 software. When significant heterogeneity was present (I2 >50% and p < 0.05), we conducted stratified and meta-regression analyses to explore possible reasons for heterogeneity.

RESULTS

We selected a total of 28 studies that were conducted in Australia, the United States, northern Europe, middle Europe, southern Europe, and Asia. The sample size of the SCD group was 6,044. Thirteen studies included a healthy control group (total control cohort of 3,822), whereas the remaining 15 studies were single-arm studies of SCD groups. The APOE e4 allele was associated with SCD (OR 1.12 [1.00-1.25]; p = 0.04). The pooled estimate for APOE e4 carrier prevalence was 32% (95% CI 28-35). Due to the significant heterogeneity in prevalence estimates, we performed stratified and meta-regression analyses and found that age and northern European residency were significantly associated with heterogeneity.

CONCLUSION

The results of this meta-analysis indicate a weak association between APOE e4 and SCD. Age and northern European residency are the critical factors that determine heterogeneity in the APOE e4-associated prevalence of SCD.

Influence of Sampling and Recruitment Methods in Studies of Subjective Cognitive Decline

Subjective cognitive decline (SCD) has been proposed as a marker of neurodegeneration in cognitively normal elderly. This idea is supported by the growing evidence that SCD is associated with Alzheimer's disease (AD) biomarkers and increases the risk of future cognitive impairment. Nevertheless, this evidence is not complete, since other studies have not found these associations. This discrepancy could have a methodological basis. It is well known that across the broad spectrum of degenerative disease from healthy controls to dementia, the research setting affects key characteristics of the sample such as age, educational level, or family history of dementia. However, virtually no studies have specifically tested the influence of sampling and recruitment methods in SCD research. Population-based samples are less biased and therefore they probably are more suitable for the study of memory complaints as a symptom at the population level. On the other hand, the memory clinic setting could introduce a set of biases that make these patients more likely to develop cognitive impairment. Thus, memory clinic would be the most cost-effective context in which to study the phenomenology of SCD due to AD and eventually recruit patients for secondary prevention trials. However, this general hypothesis needs to be tested. Studies that compare samples of patients with SCD from different settings are necessary. Sometimes it is difficult for patients with subtle forms of cognitive impairment to access specialized diagnostic centers. Based in our experience we state that Open House type initiatives may be useful for attracting these individuals to memory clinics.

Hypertensive Disorders of Pregnancy Appear Not to Be Associated with Alzheimer's Disease Later in Life

Background

After hypertensive disorders of pregnancy, more subjective cognitive complaints and white matter lesions are reported compared to women after normal pregnancies. Both have a causal relationship with Alzheimer's disease (AD).

Aim

To investigate if women whose pregnancy was complicated by hypertensive disorders have an increased risk of AD.

Methods

A case-control study in women with AD from the Alzheimer Center of the VU University Medical Center Amsterdam and women without AD. Paper and telephone surveys were performed.

Results

The response rate was 85.2%. No relation between women with (n = 104) and without AD (n = 129) reporting pregnancies complicated by hypertensive disorders (p = 0.11) was found. Women with early-onset AD reported hypertensive disorders of pregnancy more often (p = 0.02) compared to women with late-onset AD.

Conclusion

A reported history of hypertensive disorders of pregnancy appears not to be associated with AD later in life.

Hippocampal atrophy is associated with subjective memory decline: The PATH Through Life study

OBJECTIVE

To investigate whether subjective memory decline (SMD) in cognitively healthy individuals is associated with hippocampal atrophy.

METHODS

Multiple regression analyses assessing the relationship between hippocampal atrophy over 4 years and SMD at baseline and follow-up in 305 cognitively healthy individuals aged 60-64 years free from dementia, mild cognitive impairment, and other neurological disorders.

RESULTS

SMD at baseline was not a significant predictor of hippocampal atrophy. However, SMD at follow-up was associated with greater hippocampal atrophy. Associations were reduced but remained significant after controlling for anxiety and depression symptomatology.

CONCLUSION

Hippocampal atrophy was associated with incident/persisting SMD and this association was not, or only partly, explained by anxiety and depression symptomatology. These results are consistent with a biological origin to subjective memory decline. SMD should be included in screening and neuropsychological batteries.

Apolipoprotein E ε2 genotype delays onset of dementia with Lewy bodies in a Norwegian cohort

BACKGROUND

Results conflict concerning the relevance of APOE alleles on the development of dementia with Lewy bodies (DLB), though they are well established in connection with Alzheimer's disease (AD). The role of APOE alleles in a Norwegian cohort of patients with DLB was therefore examined compared with patients with AD and healthy control individuals.

METHODS

The study included 156 patients with DLB diagnosed according to the consensus criteria guidelines, 519 patients diagnosed with AD according to the National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association (NINCDS/ARDRA) criteria and 643 healthy elderly volunteers. Patients were recruited through hospitals, outpatient clinics, nursing homes or from local care authorities in central and south-western parts of Norway. Healthy individuals were recruited from caregivers and societies for retired people.

RESULTS

Subjects carrying an APOE ε2 allele had a reduced risk for developing DLB (OR 0.4, CI 0.3 to 0.8, p=0.004), and the onset of disease was delayed by 4 years (p=0.01, Mann-Whitney U test). Conversely, the APOE ε4 allele increased the risk for development of DLB (OR 5.9, CI 2.7 to 13.0, p<0.0005 for homozygotes). Similar results were found for patients with AD regarding the effect of APOE ε2, though the protective effect appeared to be slightly less pronounced than in DLB. This study is one of the largest regarding DLB and APOE to date.

CONCLUSION

The results indicate that APOE ε2, a protective factor in AD, has a clear beneficial effect on the development of DLB also.

Frequency of the apolipoprotein E ε4 allele in a memory clinic cohort in Beijing: a naturalistic descriptive study

OBJECTIVES

To describe the distribution of apolipoprotein E (APOE) genotypes among an elderly Chinese patient population with memory complaints treated in a memory clinic in Beijing and to compare the ε4 allele frequency among individuals with subjective cognitive impairment (SCI), mild cognitive impairment (MCI) and Alzheimer's disease (AD).

METHODS

A total of 385 subjects with memory complaints participated in the study, including 216 patients with AD, 56 with MCI, 17 with SCI, and 96 with other types of cognitive impairment. A total of 75 healthy elderly control subjects were also recruited. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used to investigate the APOE genotypes.

RESULTS

The frequency of the ε4 allele was 19.6 percent for the entire sample of patients who had memory complaints. The APOE allele distribution differed between women and men (22.6% and 14.9%, respectively; p<0.05) in the individuals with memory complaints. Compared with the control group (7.3%), the prevalence of the APOE ε4 allele was significantly higher in the AD (23.6%) and MCI (21.4%) groups and was slightly increased in the SCI (14.7%) group.

CONCLUSIONS

In the memory clinic, we observed a higher prevalence of the APOE ε4 allele among Chinese AD and MCI patients. A similar trend was observed in patients with SCI. These findings suggest that nondemented APOE ε4 allele carriers with memory complaints may have a greater genetic risk for AD and should be monitored more closely.

ACE polymorphism and use of ACE inhibitors: effects on memory performance

Memory is an important cognition function, being fundamental to the development and independence of individuals. Our aim was to investigate the influence apolipoprotein E (APOE) and angiotensin I-converting enzyme (ACE) polymorphism and ACE inhibitors use, besides their interaction on memory performance of healthy subjects over 50 years. The sample consisted of 205 subjects assessed for five types of episodic memory, using Wechsler Memory Scale-Revised (WMS-R), who answered a questionnaire about drug use and were assessed for the ACE insertion/deletion polymorphism and APOE polymorphism. We found no influence of the APOE gene. The use of ACE inhibitors beneficially influenced learning ability scores (p = 0.02). Besides, I allele carriers of ACE polymorphism showed higher verbal memory scores compared with homozygous DD. Also, we observed an interaction influencing learning ability between the ACE polymorphism and the use of inhibitors, the beneficial influence of the I allele was present only in individuals who make use of ACE inhibitors. We conclude that the ACE gene has influence on memory performance, and that this influence is modulated by ACE inhibitors use.

A conceptual framework for research on subjective cognitive decline in preclinical Alzheimer's disease

There is increasing evidence that subjective cognitive decline (SCD) in individuals with unimpaired performance on cognitive tests may represent the first symptomatic manifestation of Alzheimer's disease (AD). The research on SCD in early AD, however, is limited by the absence of common standards. The working group of the Subjective Cognitive Decline Initiative (SCD-I) addressed this deficiency by reaching consensus on terminology and on a conceptual framework for research on SCD in AD. In this publication, research criteria for SCD in pre-mild cognitive impairment (MCI) are presented. In addition, a list of core features proposed for reporting in SCD studies is provided, which will enable comparability of research across different settings. Finally, a set of features is presented, which in accordance with current knowledge, increases the likelihood of the presence of preclinical AD in individuals with SCD. This list is referred to as SCD plus.

ApoE4 is not associated with depression when mild cognitive impairment is considered

OBJECTIVE

The aim of the study was to examine the relationship between apolipoprotein E4 allele (ApoE4) and depression among an older Japanese population. Mild cognitive impairment (MCI) was taken into consideration.

METHODS

This is a community-based cross-sectional study. We assessed the mood and cognitive function of Japanese community-dwelling individuals aged 65 years or older. In the first phase of the study, we evaluated the mood and cognitive function. In the second phase, face-to-face structured interviews were conducted. Individuals with dementia and other mental diseases were excluded on the basis of a consensus meeting of psychiatrists and neuropsychologists; 738 subjects with full data were included in the analyses. We subdivided depression into major depressive episode (MDE) and depressive symptoms cases (DSCs). DSC was defined as a score of 6 or more on the Geriatric Depression Scale but not having a diagnosis of MDE. The relationship between depression (MDE and DSC) and ApoE4 was examined by multivariate logistic regression.

RESULTS

The adjusted odds ratio (OR) of ApoE4 on DSC was not significant (OR = 0.82, 95%CI = 0.48-1.39, p < 0.46). Sex (OR = 2.53, 95%CI = 1.33-4.79, p < 0.01), MCI (1.95, 1.21-3.14, p < 0.01), years of education (0.87, 0.79-0.95, p < 0.01), and Nishimura's activities of daily living scores (0.75, 0.63-0.89, p < 0.01) significantly correlated with prevalence of DSC. There were no significant risk factors for MDE.

CONCLUSION

Apolipoprotein E4 allele contributed to neither DSC nor MDE. The association of MCI with ApoE4 and DSC suggested that MCI is a confounder for the association between ApoE4 and DSC.

Are subjective cognitive complaints relevant in preclinical Alzheimer's disease? A review and guidelines for healthcare professionals

Identifying what makes people vulnerable to developing Alzheimer's disease (AD) is at the forefront of many research programmes, while early diagnosis is the goal in clinical practice. What individuals themselves tell their general practitioners (GPs) is clearly important because these subjective complaints may be a clue that something is wrong. More specifically, subjective cognitive complaints (SCC) may be the first sign of AD in individuals whose cognitive performance on standard neuropsychological tasks is normal for their age. The challenge for researchers in this field is twofold: (a) determining when SCC do or do not predict current cognitive functioning and future dementia; and (b) estimating how relevant they are for patients and their proxies. The current article addresses these issues, while guidelines are also provided in an attempt to help clinicians interpret and make treatment decisions about their patients’ SCC.

Regional differences in effects of APOE ε4 on cognitive impairment in non-demented subjects

BACKGROUND

The APOE ε4 allele is a risk factor for Alzheimer's disease (AD). APOE ε4 is common in non-demented subjects with cognitive impairment. In both healthy people and people with AD, its prevalence has a north-south gradient across Europe. In the present study, we investigated whether the relation between the APOE ε4 allele and cognitive impairment varied across Northern, Middle and Southern Europe. We also investigated whether a north-south gradient existed in subjects with subjective cognitive impairment (SCI), amnestic mild cognitive impairment (MCI) and non-amnestic MCI.

METHODS

Data from 16 centers across Europe were analyzed.

RESULTS

A north-south gradient in APOE ε4 prevalence existed in the total sample (62.7% for APOE ε4 carriers in the northern region, 42.1% in the middle region, and 31.5% in the southern region) and in subjects with SCI and amnestic MCI separately. Only in Middle Europe was the APOE ε4 allele significantly associated with poor performance on tests of delayed recall and learning, as well as with the amnestic subtype of MCI.

CONCLUSION

The APOE ε4 allele frequencies in subjects with SCI and amnestic MCI have a north-south gradient. The relation between the APOE ε4 allele and cognition is region dependent.

Intracranial volume and dementia: some evidence in support of the cerebral reserve hypothesis

The brain reserve hypothesis has been posited as being one important mediating factor for developing dementia, especially Alzheimer's disease (AD). Evidence for this hypothesis is mixed though different methodologies have made these findings difficult to interpret. We examined imaging data from a large cohort (N=194) of mixed dementia patients and controls, 65years old and older from the Cache County, Utah Study of Memory and Aging for evidence of the brain reserve hypothesis using total intracranial volume (TICV) as a quantitative measure of pre-morbid brain size and a vicarious indicator of reserve. A broader spectrum of non-demented elderly control subjects from previous studies was also included for comparison (N=423). In addition, non-parametric Classification and Regression Tree (CART) analyses were performed to model group heterogeneity and identify any subgroups of patients where TICV might be an important predictor of dementia. Parametrically, no main effect was found for TICV when predicting a dementia diagnosis; however, the CART analysis did reveal important TICV subgroups, including a sex differential wherein ε4 APOE allele presence in males and low TICV predicted AD classification. TICV, APOE, and other potential mediator/moderator variables are discussed in the context of the brain reserve hypothesis.

Use of genetic variation as biomarkers for mild cognitive impairment and progression of mild cognitive impairment to dementia

Cognitive impairment is prevalent in the elderly. The high estimates of conversion to dementia have spurred the interest in identification of genetic risk factors associated with development of cognitive impairment and or its progression. However, despite notable achievements in human genetics over the years, in particular technological advances in gene mapping and in statistical methods that relate genetic variants to disease, to date only a small proportion of the genetic contribution to late-life cognitive impairment can be explained. A likely explanation for the difficulty in gene identification is that it is a multifactorial disorder with both genetic and environmental components, in which several genes with small effects each are likely to contribute to the quantitative traits associated with the disease. The motivation for identifying the underlying genetic risk factors elderly is clear. Not only could it shed light on disease pathogenesis, but it may also provide potential targets for effective treatment, screening, and prevention. In this article we review the current knowledge on underlying genetic variants and the usefulness of genetic variation as diagnostic tools and biomarkers. In addition, we discuss the potentials and difficulties researchers face in designing appropriate studies for gene discovery.

Biological V. Social Definitions of Race: Implications for Modern Biomedical Research

Misconceptions concerning the concordance of biological and social definitions of race are ongoing in American society. This problem extends beyond that of the lay public into the professional arena, especially that of biomedical research. This continues, in part, because of the lack of training of many biomedical practitioners in evolutionary thinking. This essay reviews the biological and social definitions of race, examining how understanding the evolutionary mechanisms of disease is crucial to addressing ongoing health disparities. Finally it concludes by laying bear the fallacies of “race-specific” medicine.

The Italian Brain Normative Archive of structural MR scans: norms for medial temporal atrophy and white matter lesions

BACKGROUND AND AIMS

To describe the clinical and neuropsychological features of a large group of cognitively intact persons subjected to brain high-resolution magnetic resonance (MR), to compare them with the general population, and to set norms for medial temporal atrophy and white matter lesions.

METHODS

Participants in the Italian Brain Normative Archive (IBNA) study were 483 consecutive volunteers undergoing MR for reasons unrelated to cognition (migraine or headache, visual and balance or auditory disturbances, paresthesias, and others) and showing no brain damage. Manual tracing of hippocampal and amygdalar volumes and visual rating of white matter lesions were made. The whole study group was stratified by age (</=60 and 60+ yrs) and by the reason for MR prescription.

RESULTS

In the whole group, mean age and education were 52.4+/-13.7 and 9.8+/-4.2 years, respectively, and the prevalence of women was 63%. Clinical, neuropsychological and morphometric features were similar in the stratified subgroups. Neuropsychological features were those expected for age and education based on Italian normative values. Hippocampal and amygdalar volumes were not associated with age, except for the right amygdala (B -0.159, 95% CI -0.28 to -0.03, p=0.016).

CONCLUSIONS

Persons in the IBNA study had clinical and neuropsychological features consistent with that of the general population. Their brain morphometric features may be used as normative references for patients with suspected neurodegenerative disorders.

Characteristics and diagnostic profile of patients seeking dementia care in a memory clinic in Hong Kong

BACKGROUND

Seeking medical advice for dementia involves an understanding of norms, values and attitudes towards care-giving and inter-dependency, which are culturally bounded. We hypothesize that local culture and socioeconomic structure affect our Chinese patients who present with forgetfulness to our memory clinic.

METHODS

A retrospective case notes review was undertaken on 454 consecutive patients referred to the memory clinic at Princess Margaret Hospital, Hong Kong.

RESULTS

385 patients were diagnosed with dementia and 27 had mild cognitive impairment. Reversible dementia was identified in 24 patients and normal cognition in 18. In patients with dementia, 55.8% had Alzheimer's disease, 26.2% had vascular dementia, 6.0% had other irreversible dementia, 5.2% had dementia with Lewy bodies, 4.9% had undetermined dementia and 1.8% had frontotemporal dementia. The median duration from symptom onset to medical consultation was two years; 66.5% had advanced disease with initial Mini-mental State Examination scores < or = 17. On their first visit, 85% of patients were living in the community; after two years this proportion had fallen to 63%.

CONCLUSIONS

Dementia patients in Hong Kong apparently enjoy a long subclinical period and only seek medical attention at late stages. Local Chinese culture and socioeconomic backgrounds could be the main reasons that underlie these observations.