Epidemiological studies and basic research suggest a protective effect of long-chain omega-3 polyunsaturated fatty acids, antioxidants and B vitamins against brain aging. However, most randomized ...controlled trial (RCTs) with nutritional supplements have yielded disappointing effects on cognition so far. This paper suggests some original directions for future research to better support a role of nutrition in brain aging. The role of other nutrients such as docosapentaenoic acid and fat-soluble vitamins D and K should be investigated. A more holistic approach of nutrition is necessary, encompassing potential synergies between nutrients as found in a balanced diet. Potential beneficiaries of a nutritional supplementation should be better targeted, according to their dietary, cognitive and maybe genetic characteristics. Innovative RCTs should be implemented to assess the impact of nutrition for the prevention or treatment of cognitive decline in older persons, using intermediate biomarkers of disease progression and mechanisms of action of nutrients as outcomes.
Dietary fatty acids and antioxidants may contribute to decrease dementia risk, but epidemiologic data remain controversial. The aim of our study was to analyze the relationship between dietary ...patterns and risk of dementia or Alzheimer disease (AD), adjusting for sociodemographic and vascular risk factors, and taking into account the ApoE genotype.
A total of 8,085 nondemented participants aged 65 and over were included in the Three-City cohort study in Bordeaux, Dijon, and Montpellier (France) in 1999-2000 and had at least one re-examination over 4 years (rate of follow-up 89.1%). An independent committee of neurologists validated 281 incident cases of dementia (including 183 AD).
Daily consumption of fruits and vegetables was associated with a decreased risk of all cause dementia (hazard ratio HR 0.72, 95% CI 0.53 to 0.97) in fully adjusted models. Weekly consumption of fish was associated with a reduced risk of AD (HR 0.65, 95% CI 0.43 to 0.994) and all cause dementia but only among ApoE epsilon 4 noncarriers (HR 0.60, 95% CI 0.40 to 0.90). Regular use of omega-3 rich oils was associated with a decreased risk of borderline significance for all cause dementia (HR 0.46, 95% CI 0.19 to 1.11). Regular consumption of omega-6 rich oils not compensated by consumption of omega-3 rich oils or fish was associated with an increased risk of dementia (HR 2.12, 95% CI 1.30 to 3.46) among ApoE epsilon 4 noncarriers.
Frequent consumption of fruits and vegetables, fish, and omega-3 rich oils may decrease the risk of dementia and Alzheimer disease, especially among ApoE epsilon 4 noncarriers.
Epidemiological studies suggest a protective role of omega-3 poly-unsaturated fatty acids (n-3 PUFA) against Alzheimer's disease (AD). However, most intervention studies of supplementation with n-3 ...PUFA have yielded disappointing results. One reason for such discordant results may result from inadequate targeting of individuals who might benefit from the supplementation, in particular because of their genetic susceptibility to AD. The ε4 allele of the apolipoprotein E gene (ApoE) is a genetic risk factor for late-onset AD. ApoE plays a key role in the transport of cholesterol and other lipids involved in brain composition and functioning. The action of n-3 PUFA on the aging brain might therefore differ according to ApoE polymorphism. The aim of this review is to examine the interaction between dietary fatty acids and ApoE genotype on the risk for AD. Carriers of the ε4 allele tend to be the most responsive to changes in dietary fat and cholesterol. Conversely, several epidemiological studies suggest a protective effect of long-chain n-3 PUFA on cognitive decline only in those who do not carry ε4 but with inconsistent results. An intervention study showed that only non-carriers had increased concentrations of long-chain n-3 PUFA in response to supplementation. The mechanisms underlying this gene-by-diet interaction on AD risk may involve impaired fatty acids and cholesterol transport, altered metabolism of n-3 PUFA, glucose or ketones, or modification of other risk factors of AD in ε4 carriers. Further research is needed to explain the differential effect of n-3 PUFA on AD according to ApoE genotype.
To estimate the age-specific incidence rate of mild cognitive impairment (MCI) according to sex and educational level and to explore the course of MCI, particularly its progression to AD, in a ...population-based cohort.
A community-based cohort of nondemented elderly people (Personnes Agées QUID PAQUID) was followed longitudinally for 5 years. MCI was defined as memory complaints with objective memory impairment, without dementia, impairment of general cognitive functioning, or disability in activities of daily living. Incidence rates were calculated using the person-years method. A descriptive analysis at the different follow-up times was performed to study the course of MCI.
At baseline, there were 58 prevalent cases of MCI (2.8% of the sample). During a 5-year follow-up, 40 incident cases of MCI occurred in 1,265 subjects at risk. The global incidence rate of MCI was 9.9/1,000 person-years. MCI was a good predictor of AD with an annual conversion rate of 8.3% and a good specificity, but it was very unstable over time: Within 2 to 3 years, only 6% of the subjects continued to have MCI, whereas >40% reverted to normal.
Conventionally defined MCI has reasonable predictive value and specificity for AD. However, MCI was very unstable across time in this study. Furthermore, the definition of MCI seems to be too restrictive and should probably be extended to other categories of individuals also at high risk of developing AD.
Cognitive decline in the elderly, particularly Alzheimer’s disease (AD), is a major socio-economic and healthcare concern. We review here the literature on one specific aspect of diet affecting AD, ...that of the ω3 fatty acids, particularly the brain’s principle ω3 fatty acid – docosahexaenoic acid (DHA). DHA has deservedly received wide attention as a nutrient supporting both optimal brain development and for cardiovascular health. Our aim here is to critically assess the quality of the present literature as well as the potential of ω3 fatty acids to treat or delay the onset of AD. We start with a brief description of cognitive decline in the elderly, followed by an overview of well recognized biological functions of DHA. We then turn to epidemiological studies, which are largely supportive of protective effects of fish and DHA against risk of AD. However, biological studies, including blood and brain DHA analyses need careful interpretation and further investigation, without which the success of clinical trials with DHA may continue to struggle. We draw attention to some of the methodological issues that need resolution as well as an emerging mechanism that may explain how DHA could be linked to protecting brain function in the elderly.
In the PAQUID (Personnes Agées Quid) study, the authors prospectively examined flavonoid intake in relation to cognitive function and decline among subjects aged 65 years or older. A total of 1,640 ...subjects free from dementia at baseline in 1990 and with reliable dietary assessment were reexamined four times over a 10-year period. Cognitive functioning was assessed through three psychometric tests (Mini-Mental State Examination, Benton's Visual Retention Test, “Isaacs” Set Test) at each visit. Information on flavonoid intake was collected at baseline. A linear mixed model was used to analyze the evolution of cognitive performance according to quartiles of flavonoid intake. After adjustment for age, sex, and educational level, flavonoid intake was associated with better cognitive performance at baseline (p = 0.019) and with a better evolution of the performance over time (p = 0.046). Subjects included in the two highest quartiles of flavonoid intake had better cognitive evolution than did subjects in the lowest quartile. After 10 years' follow-up, subjects with the lowest flavonoid intake had lost on average 2.1 points on the Mini-Mental State Examination, whereas subjects with the highest quartile had lost 1.2 points. This gradient persisted after adjustment for several other potential confounders. This study raises the possibility that dietary flavonoid intake is associated with better cognitive evolution.
Cognitive decline may lead to dementia whose most frequent cause is Alzheimer's disease (AD). Among the many potential risk factors of cognitive decline and AD, diet raises increasing interest. Most ...studies considered diet in the frame of a single nutrient approach with inconsistent results. A novel approach to examine the link between nutrition and cognitive function is the use of dietary patterns. The aim of the present review was to update and complete the body of knowledge about dietary patterns in relationship with various cognitive outcomes in the elderly. Two approaches can be used: a priori and a posteriori patterns. A priori patterns are defined by the adhesion to a pre-defined healthy diet using a score such as the Mediterranean diet (MeDi) score, the Healthy Eating Index, the Canadian Healthy Eating Index, the French National Nutrition and Health Programme (Programme National Nutrition Santé) Guideline Score (PNNS-GS), the Recommended Food Score (RFS) and Dietary Approaches to Stop Hypertension (DASH). MeDi score, RFS, PNNS-GS and DASH have been associated with lower risks of cognitive impairment, cognitive decline, and dementia or AD. Principal components analysis, reduced rank regression and clustering methods allow the identification of ‘healthy’ patterns associated with lower risk of cognitive decline. However, some studies did not report any associations with cognitive outcomes and results are discordant especially regarding MeDi and the risk of dementia. Several methodological challenges should be overcome to provide a higher level of evidence supporting the development of nutritional policies to prevent cognitive decline and AD.
Summary
Prevention of fractures is a considerable public health challenge. In a population-based cohort of French elderly people, a diet closer to a Mediterranean type had a borderline significant ...deleterious effect on the risk of fractures, in part linked to a low consumption of dairy products and a high consumption of fruits.
Introduction
Higher adherence to the Mediterranean diet (MeDi) is linked to a lower risk of several chronic diseases, but its association with the risk of fractures is unclear. Our aim was to investigate the association between MeDi adherence and the risk of fractures in older persons.
Methods
The sample consisted of 1,482 individuals aged 67 years or older, from Bordeaux, France, included in the Three-City Study in 2001–2002. Occurrences of hip, vertebral and wrist fractures were self-reported every 2 years over 8 years, and 155 incident fractures were recorded. Adherence to the MeDi was evaluated at baseline by a MeDi score, on a 10-point scale based on a food frequency questionnaire and a 24-h recall. Multivariate Cox regression tests were performed to estimate the risk of fractures according to MeDi adherence.
Results
Higher MeDi adherence was associated with a non-significant increased risk of fractures at any site (hazard ratio HR per 1-point increase of MeDi score = 1.10,
P
= 0.08) in fully adjusted model. Among MeDi components, higher fruits consumption (>2 servings/day) was significantly associated with an increased risk of hip fractures (HR = 1.95,
P
= 0.04), while low intake of dairy products was associated with a doubled risk of wrist fractures (HR = 2.03,
P
= 0.007). An inverse U-shaped association between alcohol intake and risk of total fracture was observed (HR high vs. moderate = 0.61,
P
for trend = 0.03).
Conclusions
Greater MeDi adherence was not associated with a decreased risk of fractures in French older persons. The widely recognized beneficial effects of the MeDi do not seem to apply to bone health in these people.
OBJECTIVES: This study aimed to assess the nutritional status, measured by MNA, and its association with socio-demographic indicators and health related characteristics of a representative sample of ...community dwelling elderly subjects. DESIGN: Cross-sectional study. SETTING: Community dwelling elderly individuals living in rural communities in Lebanon. PARTICIPANTS: 1200 elderly individuals aged 65 years or more. MEASUREMENTS: Socio-demographic indicators and health related characteristics were recorded during a standardized interview. Nutritional status was assessed through Mini Nutritional Assessment (MNA). The 5-item GDS score and the WHO-5-A score were used to assess mood, whereas Mini Mental Status (MMS) was applied to evaluate cognitive status. RESULTS: The prevalence of malnutrition and risk of malnutrition was 8.0% respective 29.1% of the study sample. Malnutrition was significantly more frequent in elderly subjects aged more than 85 years, in females, widowed and illiterate people. Moreover, participants who reported lower financial status were more often malnourished or at risk of malnutrition. Regarding health status, poor nutritional status was more common among those reporting more than three chronic diseases, taking more than three drugs daily, suffering from chronic pain and those who had worse oral health status. Also, depressive disorders and cognitive dysfunction were significantly related to malnutrition. After multivariate analysis following variables remained independently associated to malnutrition: living in the governorate of Nabatieh (ORa 2.30, 95% CI 1.35–3.93), reporting higher income (ORa 0.77, 95% CI 0.61–0.97), higher number of comorbidities (ORa 1.22, 95% CI 1.12–1.32), chronic pain (ORa 1.72, 95% CI 1.24–2.39), and depressive disorders (ORa 1.66, 95% CI 1.47–1.88). On the other hand, better cognitive functioning was strongly associated with decreased nutritional risk (ORa 0.27, 95%CI 0.17–0.43). CONCLUSION: Our results highlighted the close relationship between health status and malnutrition. The identification of potential predictive factors may allow better prevention and management of malnutrition in elderly people.
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