Incidence of dementia in a population older than 75 years in the United Kingdom

Social class and the risk of dementia: A systematic review and meta-analysis of the prospective longitudinal studies

BACKGROUND

The association between belonging to a disadvantaged socio-economic status or social class and health outcomes has been consistently documented during recent decades. However, a meta-analysis quantifying the association between belonging to a lower social class and the risk of dementia has yet to be performed. In the present work, we sought to summarise the results of prospective, longitudinal studies on this topic.

METHODS

We conducted a systematic review and meta-analysis of prospective, longitudinal studies measuring the association between indicators of social class and the risk of all-cause/Alzheimer's dementia. The search was conducted in four databases (Medline, Embase, Web of Science and PsychInfo). Inclusion criteria for this systematic review and meta-analysis were: (a) longitudinal prospective study, (b) aged ⩾60 years at baseline, (c) issued from the general population, (d) no dementia at baseline and (e) mention of social class as exposure. Exclusion criteria were: (a) study of rare dementia types (e.g. frontotemporal dementia), (b) abstract-only papers and (c) articles without full text available. The Newcastle-Ottawa scale was used to assess the risk of bias in individual studies. We calculated the overall pooled relative risk of dementia for different social class indicators, both crude and adjusted for sex, age and the year of the cohort start.

RESULTS

Out of 4548 screened abstracts, 15 were included in the final analysis (76,561 participants, mean follow-up 6.7 years (2.4-25 years), mean age at baseline 75.1 years (70.6-82.1 years), mean percentage of women 58%). Social class was operationalised as levels of education, occupational class, income level, neighbourhood disadvantage and wealth. Education (relative risk (RR)=2.48; confidence interval (CI) 1.71-3.59) and occupational class (RR=2.09; CI 1.18-3.69) but not income (RR=1.28; CI 0.81-2.04) were significantly associated with the risk of dementia in the adjusted model. Some of the limitations of this study are the inclusion of studies predominantly conducted in high-income countries and the exclusion of social mobility in our analysis.

CONCLUSIONS

We conclude that there is a significant association between belonging to a social class and the risk of dementia, with education and occupation being the most relevant indicators of social class regarding this risk. Studying the relationship between belonging to a disadvantaged social class and dementia risk might be a fruitful path to diminishing the incidence of dementia over time. However, a narrow operationalisation of social class that only includes education, occupation and income may reduce the potential for such studies to inform social policies.

Sex differences in dementia risk and risk factors: Individual-participant data analysis using 21 cohorts across six continents from the COSMIC consortium

INTRODUCTION

Sex differences in dementia risk, and risk factor (RF) associations with dementia, remain uncertain across diverse ethno-regional groups.

METHODS

A total of 29,850 participants (58% women) from 21 cohorts across six continents were included in an individual participant data meta-analysis. Sex-specific hazard ratios (HRs), and women-to-men ratio of hazard ratios (RHRs) for associations between RFs and all-cause dementia were derived from mixed-effect Cox models.

RESULTS

Incident dementia occurred in 2089 (66% women) participants over 4.6 years (median). Women had higher dementia risk (HR, 1.12 [1.02, 1.23]) than men, particularly in low- and lower-middle-income economies. Associations between longer education and former alcohol use with dementia risk (RHR, 1.01 [1.00, 1.03] per year, and 0.55 [0.38, 0.79], respectively) were stronger for men than women; otherwise, there were no discernible sex differences in other RFs.

DISCUSSION

Dementia risk was higher in women than men, with possible variations by country-level income settings, but most RFs appear to work similarly in women and men.

Population-Based Studies in Dementia and Ageing Research: A Local and National Experience in Cambridgeshire and the UK

Dementia has been recognised as a key challenge in many ageing societies across the world. Several population-based studies have been developed to investigate dementia and cognitive ageing from perspectives of biology, health, psychology and social sciences. However, there is a need to provide a better understanding of 'contexts', the circumstance where these ageing populations existed, and heterogeneity within and across the populations in different time and places. In this article, we summarise some examples of earlier population-based studies undertaken by our research groups in England and Wales and their contribution to the epidemiology of dementia, neuropathology, cognitive and mental health in older age. We also describe how these studies illustrated variation among ageing populations and changes in their health conditions across time and place. These findings highlight the contribution that population-based studies can make, along with the vital to incorporate contexts in ageing research. A lifecourse approach within social context is needed to integrate life experiences, social circumstances, and multiple dimensions of cognition, functioning, physical health and wellbeing over the ageing process. We also discuss how evidence from population-based studies can support various international initiatives on dementia, healthy ageing and Sustainable Development Goals and facilitate tailored approaches for diverse populations across global societies.

From Menopause to Neurodegeneration-Molecular Basis and Potential Therapy

The impacts of menopause on neurodegenerative diseases, especially the changes in steroid hormones, have been well described in cell models, animal models, and humans. However, the therapeutic effects of hormone replacement therapy on postmenopausal women with neurodegenerative diseases remain controversial. The steroid hormones, steroid hormone receptors, and downstream signal pathways in the brain change with aging and contribute to disease progression. Estrogen and progesterone are two steroid hormones which decline in circulation and the brain during menopause. Insulin-like growth factor 1 (IGF-1), which plays an import role in neuroprotection, is rapidly decreased in serum after menopause. Here, we summarize the actions of estrogen, progesterone, and IGF-1 and their signaling pathways in the brain. Since the incidence of Alzheimer’s disease (AD) is higher in women than in men, the associations of steroid hormone changes and AD are emphasized. The signaling pathways and cellular mechanisms for how steroid hormones and IGF-1 provide neuroprotection are also addressed. Finally, the molecular mechanisms of potential estrogen modulation on N-methyl-d-aspartic acid receptors (NMDARs) are also addressed. We provide the viewpoint of why hormone therapy has inconclusive results based on signaling pathways considering their complex response to aging and hormone treatments. Nonetheless, while diagnosable AD may not be treatable by hormone therapy, its preceding stage of mild cognitive impairment may very well be treatable by hormone therapy.

Parity and the risk of incident dementia: a COSMIC study

AIMS

To investigate the association between parity and the risk of incident dementia in women.

METHODS

We pooled baseline and follow-up data for community-dwelling women aged 60 or older from six population-based, prospective cohort studies from four European and two Asian countries. We investigated the association between parity and incident dementia using Cox proportional hazards regression models adjusted for age, educational level, hypertension, diabetes mellitus and cohort, with additional analysis by dementia subtype (Alzheimer dementia (AD) and non-Alzheimer dementia (NAD)).

RESULTS

Of 9756 women dementia-free at baseline, 7010 completed one or more follow-up assessments. The mean follow-up duration was 5.4 ± 3.1 years and dementia developed in 550 participants. The number of parities was associated with the risk of incident dementia (hazard ratio (HR) = 1.07, 95% confidence interval (CI) = 1.02-1.13). Grand multiparity (five or more parities) increased the risk of dementia by 30% compared to 1-4 parities (HR = 1.30, 95% CI = 1.02-1.67). The risk of NAD increased by 12% for every parity (HR = 1.12, 95% CI = 1.02-1.23) and by 60% for grand multiparity (HR = 1.60, 95% CI = 1.00-2.55), but the risk of AD was not significantly associated with parity.

CONCLUSIONS

Grand multiparity is a significant risk factor for dementia in women. This may have particularly important implications for women in low and middle-income countries where the fertility rate and prevalence of grand multiparity are high.

Incidence of dementia in the elderly: review of age and sex effects

A review of epidemiological studies about incidence of dementia among the aged is presented. Empirical studies on incidence of dementia have shown considerably differing estimations. Nevertheless, in all studies, an age-related increase in incidence becomes clearly apparent. Epidemiological field-studies could not yield consistent findings concerning the association of incidence and gender. However, most studies found an increased incidence for men until the age of 70–80 years. In older age most studies reported the same incidence for men and women or found an increased incidence of dementia in women. The findings are reviewed and discussed in the context of methodological issues.

The Mediating Role of Perceived Social Support in the Relationships Between General Causality Orientations and Locus of Control With Psychopathological Symptoms

The main aim of this study is to investigate the mediator role of perceived social support in the relationship between general causality orientations and locus of control with psychopathological symptoms. Total 751 participants were consisted of 558 female ages between 17 and 36 (Female M = 19.03, SD = 0.09) (74.3%), 192 male ages between 17 and 37 (Male M = 20.71, SD = 0.17) (25.6%) and a participant who did not provide any gender information. We used the General Causality Orientations Scale (GCOS) and Locus of Control Scale (LOCS) in order to understand the basic motivation for the emergence of behavior. Beck depression Inventory (BDI) used to evaluate the psychological symptoms for depression, Maudsley Obsessive Compulsive Inventory (MOCI) for obsessive-compulsive symptomology and Brief Symptom Inventory (BSI) for overall psychological distress and finally to evaluate mediating role of social support used the Perceived Social Support Scale (PSSS). According to the results, having internal locus of control and autonomy orientation have shown positive effect to statistically significant predictors for psychological symptomology, having external locus of control and impersonal orientation have shown negative effect. Perceived social support was found to be suited for the role of partial mediator, and social support from friends was found to have more positive roles than social support from family. In conclusion, exceedingly considerable to conduct further research in order to contribute to the understanding of the mediating role of general causality orientations and locus of control with psychopathology symptomology.

Mild cognitive impairment: prevalence and incidence according to different diagnostic criteria

Background

Although mild cognitive impairment is associated with an increased risk of developing dementia, there has been little work on its incidence and prevalence.

Aims

To report age-specific prevalence, incidence and predictive validities for four diagnostic concepts of mild cognitive impairment.

Method

A community sample of 1045 dementia-free individuals aged 75 years and over was examined by neuropsychological testing in a three-wave longitudinal study.

Results

Prevalence rates ranged from 3% to 20%, depending on the concept applied. The annual incidence rates applying different case definitions varied from 8 to 77 per 1000 person-years. Rates of conversion to dementia over 2.6 years ranged from 23% to 47%.

Conclusions

Mild cognitive impairment is frequent in older people. Prevalence, incidence and predictive validities are highly dependent on the diagnostic criteria applied.

Differences Between Women and Men in Incidence Rates of Dementia and Alzheimer's Disease

In the following brief report, we examined gender differences in incidence rates of any dementia, Alzheimer's disease (AD) alone, and non-Alzheimer's dementia alone in 16,926 women and men in the Swedish Twin Registry aged 65+. Dementia diagnoses were based on clinical workup and national health registry linkage. Incidence rates of any dementia and AD were greater in women than men, with any dementia rates diverging after age 85 and AD rates diverging around 80. This pattern is consistent with women's survival to older ages compared to men. These findings are similar to incidence rates reported in other Swedish samples.

Neurocognitive Deficits and Effects of Cognitive Reserve in Mild Cognitive Impairment

BACKGROUND/AIMS

Mild cognitive impairment (MCI) is a frequent syndrome in the older population, which involves an increased risk to develop Alzheimer's disease (AD). The latter can be modified by the cognitive reserve, which can be operationalized by the length of school education. MCI can be differentiated into four subtypes according to the cognitive domains involved: amnestic MCI, multiple-domain amnestic MCI, non-amnestic MCI and multiple-domain non-amnestic MCI. While neurocognitive deficits are a constituent of the diagnosis of these subtypes, the question of how they refer to the cognitive reserve still needs to be clarified.

METHODS

We examined neuropsychological deficits in healthy controls, patients with MCI and patients with mild AD (n = 485) derived from a memory clinic. To reduce the number of neuropsychological variables, a factor analysis with varimax rotation was calculated. In a second step, diagnostic groups including MCI subtypes were compared with respect to their clinical and neuropsychological characteristics including cognitive reserve.

RESULTS

Most MCI patients showed the amnestic multiple-domain subtype followed by the pure amnestic subtype, while the non-amnestic subtypes were rare. The amnestic subtype displayed a significantly higher level of cognitive reserve and higher MMSE scores than the amnestic multiple-domain subtype, which was in most cases characterized by additional psychomotor and executive deficits.

CONCLUSIONS

These findings confirm earlier reports revealing that the amnestic multiple-domain subtype is the most frequent one and indicating that a high cognitive reserve may primarily prevent psychomotor and executive deficits in MCI.

Prevalence and incidence of Alzheimers disease and other dementing disorders in Pylea, Greece

We investigated the prevalence and incidence of dementing disorders in the city of Pylea, Greece, using a door-to-door three-phase approach, and explored the relationship between age and gender. From the initial cohort of 704-subjects, 112-subjects (15.9 percent) were excluded because they had moved out of town or could not be traced, 102-subjects (14.4 percent) died before the time of actual contact, and 110-subjects (15.6 percent) refused to be contacted. We were able to visit and examine 380-subjects (54 percent); each of them were administered the MMSE by one of three nurses and the CAMCOG by one of three physicians. We selected January 1, 1993, as the study prevalence day. Using specified diagnostic criteria, NINCDS-ADRDA and DSMIIIR, the study neurologists extensively investigated 118 from 380-subjects, who screened positive on MMSE (MMSE < 23) and CAMCOG (< 65). We found 35-subjects affected by dementia, 20 had Alzheimer's disease (AD), 11 had vascular or mixed dementia and four had secondary dementia (one Parkinson's disease, one Vitamin B12 deficiency, and two had Tumors). The estimated annual incidence rate for all forms of dementia, after correction for ageing of the samples was 57/1,000 persons aged > 70, made up of dementia of Alzheimer type (39.9/1,000), vascular dementia (13.9/1,000) and other forms (3.5/1,000). The prevalence of both dementia and AD increased steeply with advancing age and was consistently higher in women. The incidence of dementia increases with age, even in the oldest age groups and women have a higher risk of developing dementia than men. AD was the most common type of dementia. Our prevalence and incidence figures for dementia and AD are almost similar to those previously reported in Europe, the United States and Canada.

Can Clinical Data Predict Progression to Dementia in Amnestic Mild Cognitive Impairment?

Background:

To determine whether clinical data obtained by history and physical examination can predict eventual progression to dementia in a cohort of elderly people with mild cognitive impairment.

Methods:

A prospective, longitudinal study of a cohort of elderly subjects with amnestic Mild Cognitive Impairment (MCI). Ninety subjects meeting the criteria for amnestic MCI were recruited and followed annually for an average of 3.3 years. Main outcome measure was the development of dementia determined by clinical assessment with confirmatory neuropsychological evaluation.

Results:

Fifty patients (56%) developed dementia on follow-up. They were older, had lower Mini-mental status exam (MMSE) scores and a shorter duration of symptoms at the time of first assessment. Multivariate logistic regression analysis identified age at symptom onset as the only clinical parameter which distinguished the group that deteriorated to dementia from the group that did not. The odds ratio for age was 1.1 (confidence interval 1.04 - 1.18).

Conclusions:

Patients presenting with amnestic MCI insufficient for the diagnosis of dementia are at high risk of developing dementia on follow-up. In our cohort, 56% were diagnosed with dementia over an average period of 5.9 years from symptom onset. The only clinical predictor for the eventual development of dementia was older age at symptom onset. Clinical features alone were insufficient to predict development of dementia.

Epidemiologic studies of modifiable factors associated with cognition and dementia: systematic review and meta-analysis

Background

Cognitive impairment, including dementia, is a major health concern with the increasing aging population. Preventive measures to delay cognitive decline are of utmost importance. Alzheimer’s disease (AD) is the most frequent cause of dementia, increasing in prevalence from <1% below the age of 60 years to >40% above 85 years of age.

Methods

We systematically reviewed selected modifiable factors such as education, smoking, alcohol, physical activity, caffeine, antioxidants, homocysteine (Hcy), n-3 fatty acids that were studied in relation to various cognitive health outcomes, including incident AD. We searched MEDLINE for published literature (January 1990 through October 2012), including cross-sectional and cohort studies (sample sizes > 300). Analyses compared study finding consistency across factors, study designs and study-level characteristics. Selecting studies of incident AD, our meta-analysis estimated pooled risk ratios (RR), population attributable risk percent (PAR%) and assessed publication bias.

Results

In total, 247 studies were retrieved for systematic review. Consistency analysis for each risk factor suggested positive findings ranging from ~38.9% for caffeine to ~89% for physical activity. Education also had a significantly higher propensity for “a positive finding” compared to caffeine, smoking and antioxidant-related studies. Meta-analysis of 31 studies with incident AD yielded pooled RR for low education (RR = 1.99; 95% CI: 1.30-3.04), high Hcy (RR = 1.93; 95% CI: 1.50-2.49), and current/ever smoking status (RR = 1.37; 95% CI: 1.23-1.52) while indicating protective effects of higher physical activity and n-3 fatty acids. Estimated PAR% were particularly high for physical activity (PAR% = 31.9; 95% CI: 22.7-41.2) and smoking (PAR%=31.09%; 95% CI: 17.9-44.3). Overall, no significant publication bias was found.

Conclusions

Higher Hcy levels, lower educational attainment, and decreased physical activity were particularly strong predictors of incident AD. Further studies are needed to support other potential modifiable protective factors, such as caffeine.

Health care resource utilisation in primary care prior to and after a diagnosis of Alzheimer's disease: a retrospective, matched case-control study in the United Kingdom

BACKGROUND

This study examined medical resource utilisation patterns in the United Kingdom (UK) prior to and following Alzheimer's disease (AD) diagnosis.

METHODS

A patient cohort aged 65 years and older with newly diagnosed AD between January 2008 and December 2010 was identified through the UK's Clinical Practice Research Datalink (CPRD). Patients with a continuous record in the CPRD (formerly the General Practice Research Database [GPRD]) for both the 3 years prior to, and the 1 year following, AD diagnosis were eligible for inclusion. A control cohort was identified by matching general older adult (GOA) patients to patients with AD based on year of birth, gender, region, and Charlson Comorbidity Index at a ratio of 2:1. Medical resource utilisation was calculated in 6-month intervals over the 4-year study period. Comparisons between AD and GOA control cohorts were conducted using conditional logistic regression for patient characteristics and a generalised linear model for resource utilisation.

RESULTS

Data for the AD cohort (N = 3,896) and matched GOA control cohort (N = 7,792) were extracted from the CPRD. The groups were 65% female and the AD cohort had a mean age of 79.9 years (standard deviation 6.5 years) at the date of diagnosis. Over the entire study period, the AD cohort had a significantly higher mean primary care consultation rate than the GOA cohort (p < .0001). While the GOA cohort primary care consultation rate gradually increased over the 4-year period (ranging from 5 to 7 consultations per 6-month period), increases were more pronounced in the AD cohort (ranging from 6 to 11 consultations per 6-month period, peaking during the 6-month periods immediately prior to and post diagnosis). The AD cohort also had a higher overall specialty referral rate than the GOA cohort over the 4-year period (37% vs. 25%, respectively; p < .0001); the largest difference was during the 6 months immediately prior to AD diagnosis (17% vs. 5%, respectively; p < .0001).

CONCLUSIONS

In the UK, AD diagnosis is associated with significant increases in primary and secondary care resource utilisation, continuing beyond diagnosis. This evidence may be important to health care commissioners to facilitate effective mobilisation of appropriate AD-related health care resources.

Gender and incidence of dementia in the Framingham Heart Study from mid-adult life

BACKGROUND

Gender-specific risks for dementia and Alzheimer's disease (AD) starting in midlife remain largely unknown.

METHODS

Prospectively ascertained dementia/AD and cause-specific mortality in Framingham Heart Study (FHS) participants was used to generate 10- to 50-year risk estimates of dementia/AD on the basis of the Kaplan-Meier method (cumulative incidence) or accounting for competing risk of death (lifetime risk [LTR]).

RESULTS

Overall, 777 cases of incident dementia (601 AD) occurred in 7901 participants (4333 women) over 136,266 person-years. Whereas cumulative incidences were similar in women and men, LTRs were higher in women older than 85 years of age. LTR of dementia/AD at age 45 was 1 in 5 in women and 1 in 10 in men. Cardiovascular mortality was higher in men with rate ratios decreasing from approximately 6 at 45 to 54 years of age to less than 2 after age 65.

CONCLUSION

Selective survival of men with a healthier cardiovascular risk profile and hence lower propensity to dementia might partly explain the higher LTR of dementia/AD in women.

Cognitive impairment and mortality in older healthy Mexican subjects: a population-based 10-year follow-up study

OBJECTIVES

To estimate the incidence of cognitive impairment (CI) among cognitively healthy, Mexican subjects, and to evaluate the impact of demographic and vascular factors on the conversion to CI and mortality.

METHODS

734 eligible subjects (aged 55 to >90 years) from a population-based sample were examined. The cognitive function of participants was assessed using the Mini-Mental State Examination (MMSE) every 2 years. The subjects were followed for an average of 3.2 years. The CI was defined using two sets of criteria: (i) moderate CI, as a drop to 25-21 on the MMSE at 2-year follow-up or a decrease of at least four points and (ii) severe CI, defined as a drop of 21 or less in MMES at follow-up. The incidence density and period prevalence were determined as epidemiological measures as well as the cumulative incidence as a risk measure. Kaplan-Meier survival curves were used to analyse the main points of interest: CI, dementia and mortality.

RESULTS

The period prevalence of moderate CI was 20%, and 10% for severe CI. During 1959 person-years of follow-up, severe CI developed in 33 of the 361 participants. While during 2096 person-years of follow-up; 80 of 361 participants developed moderate CI. The rate of progression to severe CI in moderate CI subjects gradually increases with follow-up. Both, moderate and severe CI were associated with low educational level, higher age and higher mortality.

CONCLUSIONS

Elderly people with moderate CI have an increased risk of severe CI. Moderate and severe CI are both predictive of higher mortality in Mexican subjects.

Education, leisure activities and cognitive and functional ability of Alzheimer's disease patients: A follow-up study

Education and participation in leisure activities appear to be highly relevant variables in Alzheimer's disease (AD) and usually form the basis of the Cognitive Reserve construct.

Neuropsychiatric symptoms in mild cognitive impairment: An analysis and its impact on caregiving

BACKGROUND

Neuropsychiatric impairments play a significant role throughout the course of cognitive decline. Many psychological and behavioral symptoms are present in patients of mild cognitive impairment (MCI) similar to that seen in individuals with dementia.

AIMS AND OBJECTIVES

To study the relevance of neuropsychiatric symptoms of MCI and the impact it has on caregivers of these patients.

MATERIALS AND METHODS

This cross-sectional study was done on 90 patients (30 MCI, 30 dementia and 30 controls) above the age of 50 years. The scales used were Hindi-Mental Status Examination, Global deterioration scale and Neuropsychiatric inventory (NPI). Statistical analysis was done using SPSS 16 software.

RESULTS

73.33% (22) of the subjects in MCI group, 90% (27) of subjects in dementia group and 53.33% (16) of subjects having normal cognition had neuropsychiatric complaints. 73.33% (22) relatives of subjects in the MCI group, 90% (27) relatives of subjects in dementia group and 46.67% (14) relatives of subjects in the normal group (i.e. control group) experienced some distress. The differences in the mean NPI severity, frequency, distress and total scores of the three groups were statistically significant. Severity and frequency of neuropsychiatric symptoms significantly predicted the caregiver's distress.

CONCLUSIONS

Neuropsychiatric symptoms increase both in frequency and severity with increasing cognitive decline, and they cause distress both to the patient as well as the caregiver; and hence their early recognition is a must. The NPI appears to be a useful tool in that regard.

Relationship between education and dementia: an updated systematic review

OBJECTIVE

The purpose of this study was to review the relationship between education and dementia.

METHODS

A systematic literature review was conducted of all published studies examining the relationship between education and dementia listed in the PubMed and PsycINFO databases from January 1985 to July 2010. The inclusion criteria were a measure of education and a dementia diagnosis by a standardized diagnostic procedure. Alzheimer disease and Total Dementia were the outcomes.

RESULTS

A total of 88 study populations from 71 studies met inclusion criteria. Overall, 51 studies (58%) reported significant effects of lower education on risk for dementia, whereas 37 studies (42%) reported no significant relationship. A relationship between education and risk for dementia was more consistent in developed regions compared with developing regions. Age, sex, race/ethnicity, and geographical region moderated the relationship.

CONCLUSIONS

Lower education was associated with a greater risk for dementia in many but not all studies. The level of education associated with risk for dementia varied by study population and more years of education did not uniformly attenuate the risk for dementia. It seemed that a more consistent relationship with dementia occurred when years of education reflected cognitive capacity, suggesting that the effect of education on risk for dementia may be best evaluated within the context of a lifespan developmental model.

Sexual dimorphism in healthy aging and mild cognitive impairment: a DTI study

Previous PET and MRI studies have indicated that the degree to which pathology translates into clinical symptoms is strongly dependent on sex with women more likely to express pathology as a diagnosis of AD, whereas men are more resistant to clinical symptoms in the face of the same degree of pathology. Here we use DTI to investigate the difference between male and female white matter tracts in healthy older participants (24 women, 16 men) and participants with mild cognitive impairment (21 women, 12 men). Differences between control and MCI participants were found in fractional anisotropy (FA), radial diffusion (DR), axial diffusion (DA) and mean diffusion (MD). A significant main effect of sex was also reported for FA, MD and DR indices, with male control and male MCI participants having significantly more microstructural damage than their female counterparts. There was no sex by diagnosis interaction. Male MCIs also had significantly less normalised grey matter (GM) volume than female MCIs. However, in terms of absolute brain volume, male controls had significantly more brain volume than female controls. Normalised GM and WM volumes were found to decrease significantly with age with no age by sex interaction. Overall, these data suggest that the same degree of cognitive impairment is associated with greater structural damage in men compared with women.

Compliance Training in an Adult With Dementia of the Alzheimer’s Type and Down Syndrome

The authors describe the treatment of noncompliance and public stripping in a 53-year-old man with Down syndrome and dementia. On the basis of a review of the relevant literature and a comprehensive functional behavioral analysis, an intervention procedure utilizing contingent reinforcement of compliance is conducted. Compliance with requests to allow assistance getting dressed is reinforced with a combination of verbal praise, physical contact, and edible reinforcers. Noncompliance decreases by 85.22% at follow-up. Factors responsible for intervention success and implications for clinicians are discussed.

Is there a relationship between high C-reactive protein (CRP) levels and dementia?

Inflammation is believed to play a pivotal role in dementia, but its role is still unclear. The aim of our study was to analyze the interplay among markers of inflammation, such as fibrinogen and high CRP levels, and dementia. First, we performed a cross-sectional study comparing markers of inflammation between 99 patients affected by dementia (mean age: 83.0+/-0.6 years) and 99 controls (mean age: 83.9+/-0.7 years). Then, we analyzed the relationship between inflammation and dementia in the same population composed by 34 Alzheimer's disease (AD) patients (mean age: 83.4+/-0.8 years), 64 vascular dementia (VaD) patients (mean age: 82.7+0.8 years) and 99 controls. Patients affected by dementia had higher CRP levels than controls (2.6+/-+/-0.2 vs. 0.7 + 0.1 p < 0.001, respectively). AD patients had higher CRP levels than VaD patients (4.2 + 0.6 vs. 1.7+/-0.2, p < 0.001, respectively). Stepwise multiple logistic regression analysis showed that dementia (odds ratio=OR=4.965, 95% confidence interval=Cl=1.402-13.23, p=0.004), fibrinogen (OR=1.011, Cl=1.007-1.015, p<0.001), and age (OR=1.158, Cl=1.063-1.261, p<0.001) are independently correlated with high levels of CRP. The study suggests that inflammation may have a pathogenetic role in AD.

Compliance Training in an Adult With Dementia of the Alzheimer’s Type and Down Syndrome

The authors describe the treatment of noncompliance and public stripping in a 53-year-old man with Down syndrome and dementia. Based on a review of the relevant literature and a comprehensive functional behavioral analysis, an intervention procedure utilizing contingent reinforcement of compliance was conducted. Compliance with requests to allow assistance getting dressed was reinforced with a combination of verbal praise, physical contact, and edible reinforcers. Noncompliance had decreased by 85.22% at follow-up. Factors responsible for intervention success and implications for clinicians are discussed.

Risk Factors for Alzheimer's Disease: An Overview for Clinical Practitioners

OBJECTIVE

To review current information on various risk factors of Alzheimer's disease (AD) for clinicians so that they may educate patients or their families in a clinical setting.

DATA SOURCES

Published medical literature and research articles from MEDLINE.

STUDY SELECTION

Reviews and articles from 1985 to 2003 concerning risk factors associated with AD.

DATA EXTRACTION

Data on risk factors ranging from possible or controversial to well established.

DATA SYNTHESIS

AD is an irreversible, progressive neurodegenerative disorder. AD is currently known to be the most common cause of dementia in the United States. Over the last several decades, different levels of risk factors associated with AD have been identified. With more information available to the public via various resources, there is greater need for clinical practitioners to provide up-to-date information on risk factors in a meaningful way. This article discusses advanced age, family history, gender, low education, apolipoprotein E e4, head injury, cardiovascular conditions, and aluminum.

CONCLUSION

Since there currently is no cure or preventive measure for AD, it is important to educate patients and their families about risk factors of AD in clinical practice.

Accumulation of aspartic acid421- and glutamic acid391-cleaved tau in neurofibrillary tangles correlates with progression in Alzheimer disease

Truncations of tau protein at aspartic acid421 (D421) and glutamic acid391 (E391) residues are associated with neurofibrillary tangles (NFTs) in the brains of Alzheimer disease (AD) patients. Using immunohistochemistry with antibodies to D421- and E391-truncated tau (Tau-C3 and MN423, respectively), we correlated the presence of NFTs composed of these truncated tau proteins with clinical and neuropathologic parameters in 17 AD and 23 non-AD control brains. The densities of NFTs composed of D421- or E391-truncated tau correlated with clinical dementia index and Braak staging in AD. Glutamic acid391 tau truncation was prominent in the entorhinal cortex, whereas D421 truncation was prominent in the subiculum, suggesting that NFTs composed of either D421- or E391-truncated tau may be formed mutually exclusively in these areas. Both truncations were associated with the prevalence of the apolipoprotein E epsilon4 allele. By double labeling, intact tau in NFTs was commonly associated with D421-cleaved tau but not with E391-truncated tau; D421-cleaved tau was never associated with E391-truncated tau. These results indicate that tau is not randomly proteolyzed at different domains, and that proteolysis occurs sequentially from the C-terminus to inner regions of tau in AD progression. Identification of NFTs composed of tau at different stages of truncation may facilitate assessment of neurofibrillary pathology in AD.

A comparison of parametric models for the investigation of the shape of cognitive change in the older population

BACKGROUND

Cognitive decline is a major threat to well being in later life. Change scores and regression based models have often been used for its investigation. Most methods used to describe cognitive decline assume individuals lose their cognitive abilities at a constant rate with time. The investigation of the parametric curve that best describes the process has been prevented by restrictions imposed by study design limitations and methodological considerations. We propose a comparison of parametric shapes that could be considered to describe the process of cognitive decline in late life. Attrition plays a key role in the generation of missing observations in longitudinal studies of older persons. As ignoring missing observations will produce biased results and previous studies point to the important effect of the last observed cognitive score on the probability of dropout, we propose modelling both mechanisms jointly to account for these two considerations in the model likelihood.

METHODS

Data from four interview waves of a population based longitudinal study of the older population, the Cambridge City over 75 Cohort Study were used. Within a selection model process, latent growth models combined with a logistic regression model for the missing data mechanism were fitted. To illustrate advantages of the model proposed, a sensitivity analysis of the missing data assumptions was conducted.

RESULTS

Results showed that a quadratic curve describes cognitive decline best. Significant heterogeneity between individuals about mean curve parameters was identified. At all interviews, MMSE scores before dropout were significantly lower than those who remained in the study. Individuals with good functional ability were found to be less likely to dropout, as were women and younger persons in later stages of the study.

CONCLUSION

The combination of a latent growth model with a model for the missing data has permitted to make use of all available data and quantify the effect of significant predictors of dropout on the dropout and observational processes. Cognitive decline over time in older persons is often modelled as a linear process, though we have presented other parametric curves that may be considered.

Incidence of dementia, Alzheimer disease, and vascular dementia in a Japanese population: Radiation Effects Research Foundation adult health study

OBJECTIVE

To determine the age-, sex-, and subtype-specific incidence of dementia and to assess the effect of education level on the incidence in a Japanese population.

METHODS

2,286 dementia-free subjects, aged > or =60 years, were followed for 5.9 years through biennial two-phase examinations.

RESULTS

206 cases of dementia were newly diagnosed based on DSM IV. The incidence per 1,000 person-years was 12.0 for men and 16.6 for women. Based on NINCDS-ADRDA criteria, 80 cases of probable Alzheimer disease (AD) and 50 cases of possible AD were diagnosed. Based on NINDS-AIREN criteria, 36 cases of probable vascular dementia (VaD) and 40 cases of possible VaD were diagnosed. Age and education showed the most statistically significant effects for all dementia. Probable AD showed the most remarkable increase with age and decreased with increasing education level (p = 0.001). Probable VaD showed significant effects of sex (p = 0.033) and sex-age interaction (p = 0.048), but not education (p = 0.26).

CONCLUSION

AD was the predominant type of dementia in this recent incidence study conducted in Japan, suggesting a reduction in VaD and an increase in AD. Age, sex, and education effects differed by dementia subtype.

Pattern and progression of cognitive decline in Alzheimer's disease: role of premorbid intelligence and ApoE genotype

BACKGROUND/AIMS

Because of controversial results across studies, we evaluated the predictive value of premorbid intelligence and the apolipoprotein E (ApoE) genotype on baseline and progression of cognitive performance in Alzheimer's disease (AD).

METHODS

Eighty-five mild AD cases, ApoE genotyped and included in a longitudinal cliniconeuropsychological-genetic study, underwent a premorbid intelligence test and up to 11 (average 5) neuropsychological assessments. We applied linear- and logistic-regression models for cross-sectional data and mixed models for longitudinal ones.

RESULTS

Higher premorbid intelligence was associated with higher global, executive and memory performance, while the ApoE epsilon 4 allele was specifically related to poorer memory performance. The premorbid intelligence-ApoE epsilon 4/epsilon 4 interaction was significant, with higher premorbid intelligence scores reducing the detrimental effect of ApoE epsilon 4 homozygosity on memory performance. Higher premorbid intelligence, but not the ApoE epsilon 4 allele, was related to faster memory deficit progression.

CONCLUSION

The association of higher premorbid intelligence with better baseline cognitive performance and faster memory decline, as well as its interaction with the ApoE genotype, strengthens the role of cognitive reserve in shaping the disease's clinical expression. Our findings confirm that the epsilon 4 allele affects memory deficit at baseline but does not exert any influence on the rate of cognitive decline.

Lifestyle-related factors in predementia and dementia syndromes

Cognitive decline and dementia have a deep impact on the health and quality of life of older subjects and their caregivers. Since the therapeutic options currently available have demonstrated limited efficacy, the search for preventive strategies for cognitive decline and dementia are mandatory. A possible role of lifestyle-related factors was recently proposed for age-related changes of cognitive function, predementia syndromes and the cognitive decline of degenerative (Alzheimer's disease [AD]) or vascular origin. At present, cumulative evidence suggests that vascular risk factors may be important in the development of mild cognitive impairment (MCI), dementia and AD. Moderate alcohol drinking has been proposed as a protective factor against MCI and dementia in several longitudinal studies, but contrasting findings also exist. The Mediterranean diet could therefore be an interesting model with which to further study the association between dietary patterns and cognitive functioning, given the suggested role of many components of this diet (monounsaturated fatty acids, polyunsaturated fatty acids, cereals and red wine) in contrasting cognitive impairment and dementia. The association between low education and predementia and dementia syndromes is supported by the majority of studies, but very few studies have investigated whether this association may be attributed with lifestyle factors that covary with education. Studies in the literature seem to identify in physical exercise one promising strategy in decreasing cognitive decline, but some of the limitations of these studies do not allow us to draw definite conclusions. At present, in older subjects, healthy diets, antioxidant supplements, the prevention of nutritional deficiencies, and moderate physical activity could be considered the first line of defense against the development and progression of predementia and dementia syndromes. However, in most cases, these were only observational studies, and results are awaited from large multicenter randomized clinical trials in older persons that may clarify the possible synergy, for example, between moderate exercise, physical activity and healthy Mediterranean diet on cognition in the elderly.

The prevalence of dementia in an urban Turkish population

A cross-sectional, population-based, 2-stage prevalence study was conducted in a sample of 1019 community-dwelling persons over the age of 70 years living in Istanbul. In the first phase, participants were screened with the Mini-Mental State Examination for evidence of cognitive impairment. In the second phase, 79% of those who screened positive (n = 322) and 9% of screen-negatives (n = 63) underwent a standardized diagnostic workup. Diagnosis of dementia and Alzheimer's disease (AD) was made according to established criteria. Ninety-three cases of dementia were identified, 58 of whom were diagnosed with probable AD. Based on these numbers, the prevalence rates of probable AD and dementia were calculated to be 11.0% (95% CI, 7.0% to 15.0%) and 20.0% (95% CI, 14.0% to 26.0%), respectively, in this population. Prevalence rates of dementia and AD in Istanbul, Turkey, are comparable with those seen in the Western world.

Prevalence of dementia in the United States: the aging, demographics, and memory study

AIM

To estimate the prevalence of Alzheimer's disease (AD) and other dementias in the USA using a nationally representative sample.

METHODS

The Aging, Demographics, and Memory Study sample was composed of 856 individuals aged 71 years and older from the nationally representative Health and Retirement Study (HRS) who were evaluated for dementia using a comprehensive in-home assessment. An expert consensus panel used this information to assign a diagnosis of normal cognition, cognitive impairment but not demented, or dementia (and dementia subtype). Using sampling weights derived from the HRS, we estimated the national prevalence of dementia, AD and vascular dementia by age and gender.

RESULTS

The prevalence of dementia among individuals aged 71 and older was 13.9%, comprising about 3.4 million individuals in the USA in 2002. The corresponding values for AD were 9.7% and 2.4 million individuals. Dementia prevalence increased with age, from 5.0% of those aged 71-79 years to 37.4% of those aged 90 and older.

CONCLUSIONS

Dementia prevalence estimates from this first nationally representative population-based study of dementia in the USA to include subjects from all regions of the country can provide essential information for effective planning for the impending healthcare needs of the large and increasing number of individuals at risk for dementia as our population ages.

Job demands and dementia risk among male twin pairs

BACKGROUND

Job characteristics may influence dementia risk, but some types of job complexity remain to be examined. Twin studies provide a useful methodology to examine job differences between pairs who share many environmental and genetic influences.

METHODS

Members of the NAS-NRC Twins Registry of World War II Veterans received a clinical evaluation for dementia and had job ratings from the Dictionary of Occupational Titles.

RESULTS

Cotwin-control models (n = 220 pairs) indicated lower dementia risk with greater job demands of reasoning, mathematics, language, and vocational training, with comparable results in case-control models (n=425 cases). These effects were significant among twin pairs discordant for 6 or more years, but not among those discordant between 3-5 years. Results were similar for Alzheimer's disease, and main effects were not further explained by zygosity or apolipoprotein E genotype.

CONCLUSIONS

Jobs that utilize data, academic skills, and extensive vocational training may protect against dementia; however, in twin pairs these effects only emerged among individuals who remained free of dementia several years after onset in their sibling.

Cognitive reserve and Alzheimer disease

Epidemiologic evidence suggests that individuals with higher IQ, education, occupational attainment, or participation in leisure activities have a reduced risk of developing Alzheimer disease (AD). The concept of cognitive reserve (CR) posits that individual differences in how tasks are processed provide differential reserve against brain pathology or age-related changes. This may take 2 forms. In neural reserve, preexisting brain networks that are more efficient or have greater capacity may be less susceptible to disruption. In neural compensation, alternate networks may compensate for pathology's disruption of preexisting networks. Imaging studies have begun to identify the neural substrate of CR. Because CR may modulate the clinical expression of AD pathology, it is an important consideration in studies of "preclinical" AD and treatment studies. There is also the possibility that directly enhancing CR may help forestall the diagnosis of AD.

The oral health of individuals with dementia in nursing homes

OBJECTIVE

To determine if moderate to severe dementia has an effect on the oral health of individuals resident in nursing homes.

BACKGROUND

A significant proportion of the elderly population lives in nursing homes and suffers from varying degrees of dementia. Dementia might affect an individual's ability to implement oral care. Previous work in this area has focused on individuals with mild dementia living in the community setting.

MATERIAL AND METHODS

Two matched cohorts of subjects resident in four nursing homes in Cheshire were recruited (n=135). One cohort's subjects were deemed to have no or mild dementia, whereas the other cohort's subjects were deemed to have moderate to severe dementia. Oral parameters were scored, including Decayed, Missing, Filled Teeth (DMFT) scoring, dental deposit scoring, denture assessment and the noting of any other pathology.

RESULTS

There was a statistically significant difference in the relative level of dementia of the subjects between the two cohorts (p<0.01, Student's t-test). The DMFT scores were similar for both groups. The mean number (+/-SD) of decayed and missing teeth for the no/mild dementia group was 1.11 (+/-3.42) and 28.22 (+/-6.64), whilst that of the moderate/severe dementia cohort was 0.80 (+/-1.87) and 27.28 (+/-7.73), respectively. Eleven per cent of the moderate/severe dementia cohort wore an upper denture alone as compared with 16% in the no/mild dementia group.

CONCLUSION

For individuals resident in nursing homes, moderate to severe dementia might have a deleterious effect on oral health. Further work in this area is required.

Education and dementia: a meta-analytic study

Considerable controversy exists about the role of education in the risk of dementia. Individual studies have not been conclusive so far. To examine the hypothesis that lower education is associated with a higher risk of dementia, we carried out a meta-analysis. Observational studies published as of October 2005 that examined the association between education and risk of dementia were systematically reviewed. Relative risks (RRs) and odds ratios were extracted from cohort and case-control studies. We first compared the risk of dementia in subjects with high level of education with the risk of dementia in those with low educational level. In a subsequent analysis, we compared the risk of persons with high education with the risk of subjects with education level other than high (medium, low). We weighted log RRs for cohort studies or odds ratios by the inverse of their variances. Nineteen studies were included in our meta-analysis (13 cohort and 6 case-control studies). RRs for low versus high education level were: Alzheimer's disease (AD) 1.80 (95% CI: 1.43-2.27); non-AD dementias, 1.32 (95% CI: 0.92-1.88), and all dementias 1.59 (95% CI: 1.26-2.01). For low and medium versus high education level, the RRs were: AD 1.44 (95% CI: 1.24-1.67); non-AD 1.23 (95% CI: 0.94-1.61), and all dementias 1.33 (95% CI: 1.15-1.54). These results confirm that low education may be a risk factor for dementia, especially for AD.

Cognitive Reserve and Alzheimer Disease

Epidemiologic evidence suggests that individuals with higher IQ, education, occupational attainment, or participation in leisure activities have a reduced risk of developing Alzheimer disease (AD). The concept of cognitive reserve (CR) posits that individual differences in how tasks are processed provide differential reserve against brain pathology or age-related changes. This may take 2 forms. In neural reserve, preexisting brain networks that are more efficient or have greater capacity may be less susceptible to disruption. In neural compensation, alternate networks may compensate for pathology's disruption of preexisting networks. Imaging studies have begun to identify the neural substrate of CR. Because CR may modulate the clinical expression of AD pathology, it is an important consideration in studies of "preclinical" AD and treatment studies. There is also the possibility that directly enhancing CR may help forestall the diagnosis of AD.

Population-based neuropathological studies of dementia: design, methods and areas of investigation--a systematic review

Background

Prospective population-based neuropathological studies have a special place in dementia research which is under emphasised.

Methods

A systematic review of the methods of population-based neuropathological studies of dementia was carried out. These studies were assessed in relation to their representativeness of underlying populations and the clinical, neuropsychological and neuropathological approaches adopted.

Results

Six studies were found to be true population-based neuropathological studies of dementia in the older people: the Hisayama study (Japan); Vantaa 85+ study (Finland); CC75C study (Cambridge, UK); CFAS (multicentre, UK); Cache County study (Utah, USA); HAAS (Hawaï, USA). These differ in the core characteristics of their populations. The studies used standardised neuropathological methods which facilitate analyses on: clinicopathological associations and confirmation of diagnosis, assessing the validity of hierarchical models of neuropathological lesion burden; investigating the associations between neuropathological burden and risk factors including genetic factors. Examples of findings are given although there is too little overlap in the areas investigated amongst these studies to form the basis of a systematic review of the results.

Conclusion

Clinicopathological studies based on true population samples can provide unique insights in dementia. Individually they are limited in power and scope; together they represent a powerful source to translate findings from laboratory to populations.

[Proton spectroscopy in Alzheimer's disease and cognitive impairment not dementia: a community study]

OBJECTIVE

To describe the proton magnetic resonance spectroscopy (1H-ERM) data in Alzheimer's disease (AD) and Cognitive Impairment Not Dementia (CIND) in a community sample.

METHOD

We investigated subjects with AD (n=6), CIND (n=7) and normal control (n=7). 1H-ERM was performed with single voxel (8 cm3) placed in temporal, parietal and occipital regions and studied metabolites were: N-acetylaspartate (NAA), creatine (Cr), choline (Cho) and myo-inositol (mI).

RESULTS

NAA concentration was higher in control subjects than AD and intermediated in CIND patients. Cho parietal plus occipital and Cr parietal plus Cho occipital classified correctly 92.3% of subjects Control vs AD. Temporal mI classified 78.6% of subjects between Control vs CIND.

CONCLUSION

Spectroscopy can be used in the diagnosis and follow-up of individuals with cognitive impairment; evaluation of community subjects may show different patterns of brain metabolites distribution.

Incidence of dementia in very elderly individuals: a clinical, neuropathological and molecular genetic study

AIMS

To evaluate the effect of medical record use on figures for the incidence of dementia and the effect of apolipoprotein E (APOE) polymorphism on this incidence and neuropathologically defined Alzheimer's disease (AD) in very elderly individuals.

METHODS

Cognitive functions were examined in a cohort of 328 (92% of the very elderly people of a town participated in this study) nondemented Finnish elderly individuals 85 years of age or more in 1991. The examination was repeated in survivors in 1994, 1996, 1999 and 2001. Medical notes and social work records were evaluated. All these individuals were genotyped for APOE. Neuropathological analysis of AD-type pathology was performed on 159 of 303 subjects who died during the follow-up.

RESULTS

Age group, gender or APOE did not significantly affect the incidence of dementia, which was over 20% higher (85 vs. 69 per 1,000 person-years) if the cognitive status at death was ascertained by medical and social work records than without this evaluation. The APOE upsilon4 allele was highly significantly (p=0.002) and age almost significantly (p=0.06) associated with neuropathological AD in nondemented individuals.

CONCLUSIONS

Medical records should be analyzed in studies on the incidence of dementia in very elderly individuals. APOE polymorphism does not affect the incidence of dementia in this age group. However, clinical dementia diagnosis in very elderly individuals does not necessarily correlate well with the presence of neuropathological AD which, even in this age group, is significantly associated with the APOE upsilon4 allele.

Complexity of work and risk of Alzheimer's disease: a population-based study of Swedish twins

We examined the association between risk of dementia or Alzheimer's disease (AD) and occupation by using measures of complexity of work with data, people, and things. The study included 10,079 members of the population-based Swedish Twin Registry who were participants in the HARMONY study. We diagnosed dementia by means of a two-stage procedure--cognitive impairment screening followed by full clinical evaluation. We analyzed data with case-control and cotwin control designs. The cotwin control design provides control over genetic and familial factors. In the case-control study, controlling for age, gender, and level of education, we found that more complex work with people was associated with reduced risk of AD. Greater complexity of work with people and data was protective in twin pairs discordant for AD. Findings suggest that greater complexity of work, and particularly complex work with people, may reduce the risk of AD.

The incidence of dementia in England and Wales: findings from the five identical sites of the MRC CFA Study

BACKGROUND

Although incidence of dementia is known to vary between nations, variation within country has not been explored because most incidence studies are single site or have insufficient numbers to compare sites. Few countries have conducted multisite incidence studies in order to facilitate national comparisons. This study aims to provide robust measures of the variation of the incidence of dementia across sites within England and Wales and produce overall estimates by age and sex.

METHODS AND FINDINGS

The Medical Research Council Cognitive Function and Ageing Study used identical methodology in five diverse sites across the United Kingdom, each with different risk patterns and mortality rates. Incidence has been estimated using likelihood-based methods between the first two waves of interviews. Incidence rates rise with age, particularly above the age of 75 y, from 6.7 [corrected] (95% confidence interval, 3.8 [corrected]-12.4 [corrected]) per 1,000 person years at age 65-69 y to 68.5 [corrected] (95% confidence interval, 52.5 [corrected]-88.1 [corrected]) per 1,000 person years at age 85 y and above. The rate of increase for both sexes is marked, and continues into the oldest age groups. Hence, it is estimated that approximately 163,000 [corrected] new cases of dementia occur in England and Wales each year. There is no convincing evidence of variation across sites, and incidence rates do not reflect the variations in the prevalence of possible risk factors in these sites.

CONCLUSION

There is no evidence, within England and Wales, of variation in dementia incidence across sites. Dementia incidence rates do not tail off at the oldest ages.

Mediterranean diet and cognitive decline

OBJECTIVE

To investigate the possible role of diet in age-related cognitive decline (ARCD) and cognitive impairment of both degenerative (Alzheimer's disease, AD) and vascular (vascular dementia, VaD) origin.

DESIGN

Literature review.

RESULTS

In an elderly population of southern Italy with a typical Mediterranean diet, high energy intake of monounsaturated fatty acids (MUFA) appeared to be associated with a high level of protection against ARCD. In addition, dietary fat and energy in the elderly seem to be risk factors, while fish consumption and cereals are found to reduce the prevalence of AD in European and North American countries. Finally, the relative risk of dementia (AD and VaD) was lower in the subjects of a French cohort who drank three or four glasses of red wine each day compared with total abstainers.

CONCLUSION

Essential components of the Mediterranean diet--MUFA, cereals and wine--seem to be protective against cognitive decline. As such, dietary antioxidants and supplements, specific macronutrients of the Mediterranean diet, oestrogens and anti-inflammatory drugs may act synergistically with other protective factors, opening up new therapeutic interventions for cognitive decline.