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Consumption of Fish and n-3 Fatty Acids and Risk of Incident Alzheimer Disease
Martha Clare Morris, ScD;
Denis A. Evans, MD;
Julia L. Bienias, ScD;
Christine C. Tangney, PhD;
David A. Bennett, MD;
Robert S. Wilson, PhD;
Neelum Aggarwal, MD;
Julie Schneider, MD
Arch Neurol. 2003;60:940-946.
ABSTRACT
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Background Dietary n-3 polyunsaturated fatty acids improve brain functioning in animal studies, but there is limited study of whether this type of fat protects against Alzheimer disease.
Objective To examine whether fish consumption and intake of different types of n-3 fatty acids protect against Alzheimer disease.
Design Prospective study conducted from 1993 through 2000, of a stratified random sample from a geographically defined community. Participants were followed up for an average of 3.9 years for the development of Alzheimer disease.
Patients A total of 815 residents, aged 65 to 94 years, who were initially unaffected by Alzheimer disease and completed a dietary questionnaire on average 2.3 years before clinical evaluation of incident disease.
Main Outcome Measure Incident Alzheimer disease diagnosed in a structured neurologic examination by means of standardized criteria.
Results A total of 131 sample participants developed Alzheimer disease. Participants who consumed fish once per week or more had 60% less risk of Alzheimer disease compared with those who rarely or never ate fish (relative risk, 0.4; 95% confidence interval, 0.2-0.9) in a model adjusted for age and other risk factors. Total intake of n-3 polyunsaturated fatty acids was associated with reduced risk of Alzheimer disease, as was intake of docosahexaenoic acid (22:6n-3). Eicosapentaenoic acid (20:5n-3) was not associated with Alzheimer disease. The associations remained unchanged with additional adjustment for intakes of other dietary fats and of vitamin E and for cardiovascular conditions.
Conclusion Dietary intake of n-3 fatty acids and weekly consumption of fish may reduce the risk of incident Alzheimer disease.
INTRODUCTION
A PRIMARY component of membrane phospholipids in the brain is the n-3 polyunsaturated fatty acid, docosahexaenoic acid (DHA; 22:6n-3).1 High levels of DHA are found in the more metabolically active areas of the brain, including the cerebral cortex, mitochondria, synaptosomes, and synaptic vesicles.2-4 Fish is a direct dietary source of preformed DHA. In addition, DHA is synthesized endogenously through a process of desaturation and elongation of its precursor n-3 fatty acids,  -linolenic acid (18:3n-3) and eicosapentaenoic acid (EPA; 20:5n-3).5
In laboratory studies, animals fed diets enriched with n-3 polyunsaturated fatty acids had better regulation of neuronal membrane excitability,6-11 increased levels of neurotransmitters and higher density of neurotransmitter membrane receptors,12-16 increased hippocampal nerve growth,17 greater fluidity of synaptic membranes,18 higher levels of antioxidant enzymes,19 decreased levels of lipid peroxides,20 reduced ischemic damage to neurons,21 and increased cerebral blood flow.22-23 In behavioral models, animals fed diets enriched with n-3 fatty acids had superior learning acquisition and memory performance over animals fed control diets.4, 18, 24-31
Epidemiologic investigation of dietary n-3 fatty acids and Alzheimer disease is limited. One case-control study reported that n-3 fatty acid levels in plasma phospholipids of patients with Alzheimer disease were 60% to 70% of levels found in age-matched control subjects.32 Two prospective studies found that fish consumption was inversely associated with risk of incident Alzheimer disease.33-34 We examined whether fish consumption and intake of DHA and other n-3 fatty acids were associated with protection against Alzheimer disease in a biracial community.
METHODS
POPULATION
Participants were from the Chicago Health and Aging Project, a population-based study of risk factors for incident Alzheimer disease.35 In a 1993 to 1997 census of a south-side Chicago, Ill, community, 8501 residents 65 years and older were identified, of whom 6158 (78.8% of 7813 surviving residents) participated in 90-minute interviews that included the administration of 4 cognitive tests.36-39 The study population was 62% black, 38% white, and 61% female, with a mean educational level of 11.8 years.
Subsequent to the population interview, 1056 participants were randomly selected for clinical evaluation of prevalent Alzheimer disease, and 729 of them were evaluated (76% of 961 surviving residents). Sample selection was within strata defined by age, sex, race, and cognitive performance (good, intermediate, or poor). This phase of the study identified a cohort of 3838 unaffected persons to follow up for incident disease. The disease-free cohort consisted of 3352 persons who had good performance on the baseline cognitive tests, and 486 whose cognitive performance was intermediate or poor but who were unaffected by Alzheimer disease at the baseline clinical evaluation.
Three years after the baseline interview, all participants were recontacted for follow-up interviews, and 4320 participated (86.7% response among 4983 surviving residents). A second random sample stratified by age, sex, race, and decline in cognitive performance (no, small, or large decline) was selected from the disease-free cohort for clinical evaluation of incident Alzheimer disease. Random selection occurred with different sampling probabilities within the strata to ensure that persons most likely to have Alzheimer disease were sampled and that a sufficient number of comparable persons who were unaffected were also selected. Of the 1249 selected, 842 persons agreed to participate (73.9% of 1140 survivors), and 815 had complete data for the analysis of fish consumption and incident disease.
The institutional review board of Rush-Presbyterian-St Luke's Medical Center approved the study, and all participants (or legal guardian) gave written consent. Descriptions of the population interviews40 and clinical evaluations35 have been published previously.
DIETARY ASSESSMENT
Diet was assessed on average 1.9 years after baseline (or 2.3 years before the clinical evaluations) by means of a modified Harvard self-administered food frequency questionnaire (FFQ).41 The FFQ was distributed to participants along with a self-addressed envelope for its return. The 154-question FFQ (139 food items) included 4 seafood items (tuna fish sandwich, fish sticks/fish cakes/fish sandwich, fresh fish as a main dish, and shrimp/lobster/crab). Other questions inquired about use of vitamin supplements, specific brand names of cereals and margarines, type of cooking oil, and fat preferences for milk and meat products that were used in the computation of nutrient intake. Nutrient intake was obtained by multiplying the nutrient content of individual food items by the frequency of consumption and summing over all items. Nutrient content of individual food items was based on the Harvard University Nutrient Composition Database, which is continually updated through the US Department of Agriculture sources,42 along with selected individual publications. For analysis, estimated intake levels of all nutrients and fats were energy-adjusted by means of the regression residual method.43 Total n-3 fatty acid intake was based on the sum of 18:3n-3 (-linolenic acid), 20:5n-3 (EPA), 22:5n-3, and 22:6n-3 (DHA). Weekly consumption of fish was computed by summing the responses to frequency of intake for the 3 fish items.
In a reproducibility and validity study of randomly selected Chicago Health and Aging Project participants, Spearman rank correlation coefficients between 2 FFQs completed approximately 1 year apart for 139 persons were 0.55 for total intake of n-3 fatty acids, 0.58 for DHA intake, and 0.44 for EPA intake (all P<.001). Pearson correlation coefficient was 0.33 (P = .01) between plasma levels of marine n-3 fatty acids and the FFQ in 56 participants.
CLINICAL EVALUATION FOR INCIDENT ALZHEIMER DISEASE
Alzheimer disease was diagnosed on the basis of structured neurologic clinical evaluations that were conducted in participants' homes by a team consisting of a neurologist, a nurse practitioner, a phlebotomist, and a neuropsychological technician. The evaluations included a complete medical history and neurologic examination, medication use, neuropsychological testing (using the tests of the Consortium Established for Research on Alzheimer's Disease44 and others36, 45-51), informant interviews for cognitively impaired individuals, and laboratory testing. Diagnostic use of magnetic resonance imaging was restricted to persons with evidence of dementia and uncertainty as to whether a stroke had occurred or was related to the dementia. A board-certified neurologist, blinded to participants' dietary information, reexamined each patient and reviewed all clinical data. The diagnosis of probable Alzheimer disease was based on criteria of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Associated Disorders Association.52 For analyses, the definition included all cases of Alzheimer disease, including 14 cases with a coexisting dementing condition. Demented persons without Alzheimer disease (n = 11) were analyzed as noncases. Apolipoprotein E genotyping was conducted by methods of Hixson and Vernier53 and the primers described by Wenham et al.54
COVARIATES
Race questions and categories were those used by the 1990 US census. Age was computed from self-reported birth date and date of disease-free status. All nondietary variables except clinical stroke were obtained at the baseline population interview, which included interviewer inspection of all medications taken within the previous 2 weeks. Level of education was computed from self-reported highest grade or years of formal education. History of hypertension was defined as antihypertensive medication use or participant report of high blood pressure. Heart disease was defined as self-reported history of heart attack, use of digitalis, or evidence of angina pectoris based on participant responses to a standardized questionnaire.55 History of stroke was defined as probable or possible stroke as diagnosed at the clinical evaluation by a neurologist on the basis of a uniform, structured examination, medical history, and magnetic resonance imaging diagnostic testing.
STATISTICAL METHODS
We used logistic regression programmed in SAS56 to generate odds ratios as estimates of the relative risk of incident Alzheimer disease. All statistics and models were weighted for the stratified random sample design so that the study results could be referred back to the population unaffected by disease at baseline. Variance estimations for all parameters were based on jackknife repeated replication.57-58 We modeled the different types of energy-adjusted n-3 fatty acids in quintiles, using the first quintile as the referent. Analyses with the nutrients modeled as continuous variables produced the same results. The multivariable model included terms for age (years), sex, race (black or white), education (years), apolipoprotein E (APOE)– 4 status (any 4 allele vs none), and the interaction between race and APOE-4. The multivariable model for fish consumption also included total energy intake. Confounding by other dietary components was examined in the multivariable model with other dietary variables modeled as continuous log-transformed variables. Effect modification was examined for fish consumption (trend variable) and each nutrient (modeled as continuous variables) in multivariable models that included a multiplicative term between the nutrient and potential effect modifier.
RESULTS
At baseline, the 815 sample participants ranged in age from 65 to 94 years. After a mean follow-up of 3.9 years, 131 persons were diagnosed as having incident Alzheimer disease, for an annual incidence rate of 2.6% weighted for the stratified random sample design. Less than 1% of the sample was taking n-3 fatty acid dietary supplements. Of the 3 different types of fish, fresh fish as a main dish was the most frequently consumed, with 39.2% of sample participants reporting intake at least weekly compared with 13.9% consuming tuna fish sandwiches; 8.5%, fish sticks/cakes/sandwiches; and 2.4%, shellfish. Compared with persons in the lowest quintile of n-3 polyunsaturated fat intake, those in the highest quintile group were more likely to be male, to have more years of education, to have a history of hypertension, and to have lower consumption of vitamin E and higher consumption of all types of fat (Table 1).
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Table 1. Baseline Characteristics* by Quintiles of Total n-3 Fatty Acid Intake Among 815 Participants 65 Years and Older, Chicago Health and Aging Project, 1993-1997
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FISH CONSUMPTION
Fish consumption was inversely associated with the risk of incident Alzheimer disease. The age-adjusted relative risks for at least weekly fish consumption were in the protective direction but not statistically significant. These became stronger and statistically significant with additional control for other risk factors, including sex, race, education, presence of the APOE-4 allele, and total energy intake (Table 2). Persons who consumed 1 fish meal per week or more than 1 fish meal per week had 60% less risk of Alzheimer disease than did persons who reported eating fish rarely or never (for both groups, relative risk, 0.4; 95% confidence interval, 0.2-0.9). Because of the possibility that persons with cardiovascular conditions increased their fish intake as a preventive measure (see Table 1), we reanalyzed the data after excluding weekly fish consumers who reported that they ate more fish now than 10 years previously. The association was more protective in this restricted group (n = 641). In the multivariable model with additional adjustment for histories of stroke, heart disease, and hypertension, the relative risk was 0.4 (95% confidence interval, 0.2-0.8) for 1 fish meal per week and 0.3 (95% confidence interval, 0.1-0.6) for 2 or more per week when compared with nonconsumers.
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Table 2. Relative Risk of Incident Alzheimer Disease (AD) by Frequency of Fish Consumption Among 815 Participants With 3.9 Years of Follow-up, Chicago Health and Aging Project, 1993-2000
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n-3 FATTY ACID INTAKE
Total intake of the n-3 polyunsaturated fatty acids was inversely and linearly associated with risk of incident Alzheimer disease in both the age- and multivariable-adjusted models (in each model, P for linear trend = .01) (Table 3). Persons in the top fifth of intake had a statistically significant 70% reduction in risk compared with persons in the lowest fifth of intake with adjustment for age. The relative risk was slightly modified in the multivariable model but remained statistically significant. There was also a linear protective association with intake of DHA (22:6n-3). The inverse relative risks were more protective than for total n-3 fatty acid intake, with statistically significant 60% to 80% reductions in risk for the upper 3 quintiles in the multivariable model. The range of intake of EPA (20:5n-3) was low, with 40% of participants consuming 0 g/d. Therefore, we compared the risk of Alzheimer disease for persons in each of the top three fifths of intake with the risk of persons in the lowest two fifths. The age-adjusted risk of Alzheimer disease did not differ significantly across the quintiles of EPA intake, and additional control for other potential confounders had little effect on the relative risk estimates. Another type of n-3 fatty acid found primarily in oil-based salad dressing and nuts, -linolenic acid, had a modest inverse association with incident Alzheimer disease in the age-adjusted model (P for trend = .01) that was not apparent after adjustment for the effects of other risk factors.
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Table 3. Relative Risks for Incident Alzheimer Disease (AD) by Quintile of Intake of n-3 Fatty Acids, Docosahexaenoic Acid (DHA), and Eicosapentaenoic Acid (EPA) Among 815 Persons After 3.9 Years of Follow-up, Chicago Health and Aging Project, 1993-2000
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The multivariable relative risks for intakes of DHA (22:6n-3), EPA (20:5n-3), or total n-3 fatty acids did not change materially when we controlled for intake of dietary vitamin E, other types of fat (n-6 polyunsaturated, monounsaturated, saturated, trans-unsaturated), or cardiovascular diseases (stroke, heart disease, hypertension). The multivariable relative risks for intake of -linolenic acid were approximately 1.0 with adjustment for vitamin E intake, but were unchanged when adjusted for cardiovascular disease.
In further analyses, we examined each n-3 fatty acid and fish consumption for evidence of effect modification. Intake of -linolenic acid was strongly protective among persons with the APOE-4 allele (multivariate relative risk, 0.08 per natural log [milligram] increase in linolenic acid; P = .02), but there was no apparent association among persons who were 4 negative. The interaction remained statistically significant with additional control for intake of vitamin E or other types of fat. In addition, total intake of n-3 fatty acids was protective only among women (P for interaction = .02). Otherwise, there was no evidence that age, sex, race, education, or APOE-4 genotype modified the effects.
To examine the possibility that the observed associations may be due to dietary changes or inaccurate reporting among persons with cognitive impairment, we reanalyzed the data after deleting data for persons whose baseline cognitive scores ranked in the lowest 10% of the distribution. The protective association with intake of total n-3 fatty acids became stronger (the multivariable relative risks [95% confidence intervals] for quintiles 2 through 5 were 0.4 [0.1-1.0], 0.4 [0.1-1.3], 0.4 [0.1-0.8], and 0.3 [0.1-0.8]). The multivariable relative risks for quintiles of DHA intake did not change appreciably except for the highest quintile, in which the relative risk was modified, to 0.5 from 0.3 in the total sample. Adjustment for the timing of the dietary assessment had little influence on the estimated relative risks.
COMMENT
Consumption of the n-3 polyunsaturated fatty acids and fish was associated with reduced risk of incident Alzheimer disease in this large prospective study. Persons who consumed at least 1 fish meal per week had 60% less risk of Alzheimer disease than did persons who rarely or never ate fish. Of the marine n-3 fatty acids, only DHA (22:6n-3) was protective against the development of Alzheimer disease. Intake of -linolenic acid was also protective, but only among persons with the APOE-4 genotype.
The study has a number of strengths that support the validity of the findings. Protective associations were observed for DHA, a major component of brain phospholipids, with fish, its primary food source, and with -linolenic acid, which is largely obtained from vegetable oils. The strength of these associations makes it unlikely that the findings are due to chance. These associations held even after adjustment for education and other important risk factors, including cardiovascular conditions that could potentially account for the observed relative risks. The study participants were randomly selected from the general population, and all underwent structured clinical evaluation for incident disease, thus minimizing bias due to participant selection or case detection. The examiners were blinded to participants' dietary habits, and the dietary assessments were completed before clinical evaluation for incident disease. A limitation of the study is that, for a large number of participants, the dietary assessments were not obtained at baseline. This could have biased the results if some of these participants had already developed disease when their diet was assessed, and also changed their diet. For several reasons, this alternative explanation of the protective associations appears unlikely. The results did not change when we eliminated persons with low cognitive scores at baseline, or when we controlled for the timing of the dietary assessments. Furthermore, in a previous analysis of 2953 participants of the larger study, we found significantly less cognitive decline among persons who consumed fish at least weekly.59
We did not observe a protective benefit from EPA (20:5n-3); however, the range of intake was low, and we cannot rule out an effect at higher dose levels obtained from cold-water fatty fish or fish oil supplements. The EPA levels in most low-fat fresh fish are negligible. In a random sample of 232 persons from the study population, more than 90% of the fresh fish that was reported in 24-hour dietary recalls was very low in fat.
This study supports the protective associations found by the 2 other epidemiologic studies that examined the relationship between fish consumption and incident Alzheimer disease.33-34 Numerous animal models provide evidence of a biological basis for the association. The n-3 fatty acids have been studied extensively for their antiatherosclerotic properties.5 Notably, it was DHA that had the strongest protective effect against Alzheimer disease. Docosahexaenoic acid is the most abundant fatty acid in the phospholipids of the cerebral gray matter and represents 45% to 65% of total phosphatidylserine in the mitochondria, which plays a role in neuronal signaling.2 Docosahexaenoic acid is selectively accumulated in the brain during fetal and infant brain growth.2 However, several studies have shown that it is possible to increase n-3 fatty acids in the brain through diet well after the period of early brain development.7, 19, 60 There is a high turnover of phospholipid fatty acids in the brain.1 In one study, consumption of preformed DHA was 7 times more likely to result in uptake by the brain than DHA derived through consumption of linolenic acid.61 Several prospective studies found decreased risk of stroke with increased fish consumption62-64 and intake of n-3 fatty acids.62
The n-3 polyunsaturated fatty acids have been shown to have profound effects on membrane functions, leading to change in nerve conduction, neurotransmitter release, neurotransmitter reuptake, and postsynaptic transmitter effects. A large number of animal studies have demonstrated that dietary n-3 fatty acids increased learning acquisition and memory performance,4, 18, 24-31 and 2 epidemiologic studies found decreased risk of Alzheimer disease with increased fish consumption.33-34 These studies, together with our finding that consumption of fish and n-3 fatty acids was associated with reduced risk of Alzheimer disease, provide a strong basis for further study through epidemiologic investigations and clinical trials. Our findings suggest that consumption of fish (at least weekly), oil-based salad dressings, and nuts may reduce the risk of Alzheimer disease.
AUTHOR INFORMATION
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Corresponding author and reprints: Martha Clare Morris, ScD, Rush Institute for Healthy Aging, 1645 W Jackson, Suite 675, Chicago, IL 60612 (e-mail: Martha_C_Morris{at}rush.edu).
Accepted for publication January 10, 2003.
Author contributions: Study concept and design (Drs Morris, Evans, and Bennett); acquisition of data (Drs Morris, Evans, Tangney, Bennett, Aggarwal, and Schneider); analysis and interpretation of data (Drs Morris, Evans, Bienias, Tangney, Bennett, and Wilson); drafting of the manuscript (Dr Morris); critical revision of the manuscript for important intellectual content (Drs Morris, Evans, Bienias, Tangney, Bennett, Wilson, Aggarwal, and Schneider); statistical expertise (Drs Morris and Bienias); obtained funding (Drs Morris, Evans, and Bennett); administrative, technical, and material support (Drs Morris, Evans, Wilson, Aggarwal, and Schneider); study supervision (Drs Morris, Evans, Tangney, and Bennett).
This study was supported by grants AG11101, AG13170, and AG10161 from the National Institute on Aging, Bethesda, Md.
We gratefully acknowledge the work of study coordinators Cheryl Bibbs, Michelle Bos, MA, Jennifer Tarpey, and Flavio Lamorticella, their staffs, and the analytic programmer, Woojeong Bang, MS.
From the Rush Institute for Healthy Aging (Drs Morris, Evans, Bienias, Bennett, and Wilson), Departments of Internal Medicine (Drs Morris, Evans, and Bienias) and Preventive Medicine (Dr Morris), Rush Alzheimer's Disease Center (Drs Evans, Bennett, Wilson, Aggarwal, and Schneider), and Departments of Clinical Nutrition (Dr Tangney), Neurological Sciences (Drs Bennett, Wilson, Aggarwal, and Schneider), and Psychology (Dr Wilson), Rush-Presbyterian-St Luke's Medical Center, Chicago, Ill.
REFERENCES
1. Connor WE, Neuringer M, Lin DS. Dietary effects on brain fatty acid composition: the reversibility of n-3 fatty acid deficiency and turnover of docosahexaenoic acid in the brain, erythrocytes, and plasma of rhesus monkeys. J Lipid Res. 1990;31:237-247.
ABSTRACT
2. Hamilton L, Greiner R, Salem N Jr, Kim HY. n-3 Fatty acid deficiency decreases phosphatidylserine accumulation selectively in neuronal tissues. Lipids. 2000;35:863-869.
FULL TEXT
|
ISI
| PUBMED
3. Carrie I, Clement M, de Javel D, Frances H, Bourre JM. Specific phospholipid fatty acid composition of brain regions in mice: effects of n-3 polyunsaturated fatty acid deficiency and phospholipid supplementation. J Lipid Res. 2000;41:465-472.
FREE FULL TEXT
4. Gamoh S, Hashimoto M, Sugioka K, et al. Chronic administration of docosahexaenoic acid improves reference memory-related learning ability in young rats. Neuroscience. 1999;93:237-241.
FULL TEXT
|
ISI
| PUBMED
5. Leaf A, Weber P. Cardiovascular effects of n-3 fatty acids. N Engl J Med. 1988;318:549-557.
ISI
| PUBMED
6. Itokazu N, Ikegaya Y, Nishikawa M, Matsuki N. Bidirectional actions of docosahexaenoic acid on hippocampal neurotransmissions in vivo. Brain Res. 2000;862:211-216.
FULL TEXT
|
ISI
| PUBMED
7. McGahon BM, Martin DS, Horrobin DF, Lynch MA. Age-related changes in synaptic function: analysis of the effect of dietary supplementation with  -3 fatty acids. Neuroscience. 1999;94:305-314.
FULL TEXT
|
ISI
| PUBMED
8. Xiao Y, Li X. Polyunsaturated fatty acids modify mouse hippocampal neuronal excitability during excitotoxic or convulsant stimulation. Brain Res. 1999;846:112-121.
FULL TEXT
|
ISI
| PUBMED
9. Vreugdenhil M, Bruehl C, Voskuyl RA, Kang JX, Leaf A, Wadman WJ. Polyunsaturated fatty acids modulate sodium and calcium currents in CA1 neurons. Proc Natl Acad Sci U S A. 1996;93:12559-12563.
FREE FULL TEXT
10. Young C, Gean PW, Chiou LC, Shen YZ. Docosahexaenoic acid inhibits synaptic transmission and epileptiform activity in the rat hippocampus. Synapse. 2000;37:90-94.
FULL TEXT
|
ISI
| PUBMED
11. Poling JS, Vicini S, Rogawski MA, Salem N Jr. Docosahexaenoic acid block of neuronal voltage-gated K+ channels: subunit selective antagonism by zinc. Neuropharmacology. 1996;35:969-982.
FULL TEXT
|
ISI
| PUBMED
12. Innis SM. The role of dietary n-6 and n-3 fatty acids in the developing brain. Dev Neurosci. 2000;22:474-480.
FULL TEXT
|
ISI
| PUBMED
13. de la Presa Owens S, Innis SM. Docosahexaenoic and arachidonic acid prevent a decrease in dopaminergic and serotoninergic neurotransmitters in frontal cortex caused by a linoleic and -linolenic acid deficient diet in formula-fed piglets. J Nutr. 1999;129:2088-2093.
FREE FULL TEXT
14. de la Presa Owens S, Innis SM. Diverse, region-specific effects of addition of arachidonic and docosahexanoic acids to formula with low or adequate linoleic and -linolenic acids on piglet brain monoaminergic neurotransmitters. Pediatr Res. 2000;48:125-130.
ISI
| PUBMED
15. Chalon S, Delion-Vancassel S, Belzung C, et al. Dietary fish oil affects monoaminergic neurotransmission and behavior in rats. J Nutr. 1998;128:2512-2519.
FREE FULL TEXT
16. Delion S, Chalon S, Guilloteau D, Besnard JC, Durand G. -Linolenic acid dietary deficiency alters age-related changes of dopaminergic and serotoninergic neurotransmission in the rat frontal cortex. J Neurochem. 1996;66:1582-1591.
ISI
| PUBMED
17. Ikemoto A, Nitta A, Furukawa S, et al. Dietary n-3 fatty acid deficiency decreases nerve growth factor content in rat hippocampus. Neurosci Lett. 2000;285:99-102.
FULL TEXT
|
ISI
| PUBMED
18. Suzuki H, Park SJ, Tamura M, Ando S. Effect of the long-term feeding of dietary lipids on the learning ability, fatty acid composition of brain stem phospholipids and synaptic membrane fluidity in adult mice: a comparison of sardine oil diet with palm oil diet. Mech Ageing Dev. 1998;101:119-128.
FULL TEXT
|
ISI
| PUBMED
19. Hossain MS, Hashimoto M, Masumura S. Influence of docosahexaenoic acid on cerebral lipid peroxide level in aged rats with and without hypercholesterolemia. Neurosci Lett. 1998;244:157-160.
FULL TEXT
|
ISI
| PUBMED
20. Kubo K, Saito M, Tadokoro T, Maekawa A. Dietary docosahexaenoic acid dose does not promote lipid peroxidation in rat tissue to the extent expected from peroxidizability index of the lipids. Biosci Biotechnol Biochem. 1998;62:1698-1706.
FULL TEXT
| PUBMED
21. Okada M, Amamoto T, Tomonaga M, et al. The chronic administration of docosahexaenoic acid reduces the spatial cognitive deficit following transient forebrain ischemia in rats. Neuroscience. 1996;71:17-25.
FULL TEXT
|
ISI
| PUBMED
22. Tsukada H, Kakiuchi T, Fukumoto D, Nishiyama S, Koga K. Docosahexaenoic acid (DHA) improves the age-related impairment of the coupling mechanism between neuronal activation and functional cerebral blood flow response: a PET study in conscious monkeys. Brain Res. 2000;862:180-186.
FULL TEXT
|
ISI
| PUBMED
23. Katayama Y, Katsumata T, Muramatsu H, Usuda K, Obo R, Terashi A. Effect of long-term administration of ethyl eicosapentate (EPA-E) on local cerebral blood flow and glucose utilization in stroke-prone spontaneously hypertensive rats (SHRSP). Brain Res. 1997;761:300-305.
FULL TEXT
|
ISI
| PUBMED
24. Carrie I, Clement M, de Javel D, Frances H, Bourre JM. Phospholipid supplementation reverses behavioral and biochemical alterations induced by n-3 polyunsaturated fatty acid deficiency in mice. J Lipid Res. 2000;41:473-480.
FREE FULL TEXT
25. Moriguchi T, Greiner RS, Salem N Jr. Behavioral deficits associated with dietary induction of decreased brain docosahexaenoic acid concentration. J Neurochem. 2000;75:2563-2573.
FULL TEXT
|
ISI
| PUBMED
26. Lim SY, Suzuki H. Intakes of dietary docosahexaenoic acid ethyl ester and egg phosphatidylcholine improve maze-learning ability in young and old mice. J Nutr. 2000;130:1629-1632.
FREE FULL TEXT
27. Lim SY, Suzuki H. Effect of dietary docosahexaenoic acid and phosphatidylcholine on maze behavior and fatty acid composition of plasma and brain lipids in mice. Int J Vitam Nutr Res. 2000;70:251-259.
FULL TEXT
|
ISI
| PUBMED
28. Greiner RS, Moriguchi T, Hutton A, Slotnick BM, Salem N Jr. Rats with low levels of brain docosahexaenoic acid show impaired performance in olfactory-based and spatial learning tasks. Lipids. 1999;34(suppl):S239-S243.
29. Minami M, Kimura S, Endo T, et al. Dietary docosahexaenoic acid increases cerebral acetylcholine levels and improves passive avoidance performance in stroke-prone spontaneously hypertensive rats. Pharmacol Biochem Behav. 1997;58:1123-1129.
FULL TEXT
|
ISI
| PUBMED
30. Jensen MM, Skarsfeldt T, Hoy CE. Correlation between level of (n-3) polyunsaturated fatty acids in brain phospholipids and learning ability in rats: a multiple generation study. Biochim Biophys Acta. 1996;1300:203-209.
PUBMED
31. Yamamoto N, Saitoh M, Moriuchi A, Nomura M, Okuyama H. Effect of dietary alpha-linolenate/linoleate balance on brain lipid compositions and learning ability of rats. J Lipid Res. 1987;28:144-151.
ABSTRACT
32. Conquer JA, Tierney MC, Zecevic J, Bettger WJ, Fisher RH. Fatty acid analysis of blood plasma of patients with Alzheimer's disease, other types of dementia, and cognitive impairment. Lipids. 2000;35:1305-1312.
ISI
| PUBMED
33. Barberger-Gateau P, Letenneur L, Deschamps V, Peres K, Dartigues JF, Renaud S. Fish, meat, and risk of dementia: cohort study. BMJ. 2002;325:932-933.
FREE FULL TEXT
34. Kalmijn S, Launer LJ, Ott A, Witteman JC, Hofman A, Breteler MM. Dietary fat intake and the risk of incident dementia in the Rotterdam Study. Ann Neurol. 1997;42:776-782.
FULL TEXT
|
ISI
| PUBMED
35. Evans DA, Bennett DA, Wilson RS, et al. Incidence of Alzheimer's disease in a biracial urban community: relation to apolipoprotein E allele status. Arch Neurol. 2003;60:185-189.
FREE FULL TEXT
36. Albert MS, Smith LA, Scherr PA, et al. Use of brief cognitive tests to identify individuals in the community with clinically-diagnosed Alzheimer's disease. Int J Neurosci. 1991;57:167-178.
ISI
| PUBMED
37. Scherr PA, Albert MS, Funkenstein HH, et al. Correlates of cognitive function in an elderly community population. Am J Epidemiol. 1988;128:1084-1101.
FREE FULL TEXT
38. Smith A. Symbol Digit Modalities Test Manual–Revised. Los Angeles, Calif: Western Psychological Corp; 1984.
39. Folstein MF, Folstein SE, McHugh PR. "Mini-mental state": a practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res. 1975;12:189-198.
FULL TEXT
|
ISI
| PUBMED
40. Morris MC, Evans DA, Bienias JL, Tangney CC, Wilson RS. Vitamin E and cognitive decline in older persons. Arch Neurol. 2002;59:1125-1132.
FREE FULL TEXT
41. Morris MC, Colditz GA, Evans DA. Response to a mail nutritional survey in an older bi-racial community population. Ann Epidemiol. 1998;8:342-346.
FULL TEXT
|
ISI
| PUBMED
42. USDA Nutrient Database for Standard Reference. Release 10. Washington, DC: US Dept of Agriculture; 1996.
43. Willett WC, Stampfer MJ. Total energy intake: implications for epidemiologic analysis. Am J Epidemiol. 1986;124:17-27.
FREE FULL TEXT
44. Welsh KA, Butters N, Mohs R, et al. CERAD part V: a normative study of the neuropsychological battery. Neurology. 1994;44:609-614.
FREE FULL TEXT
45. Wechsler D. Wechsler Memory Scale–Revised Manual. New York, NY: Psychological Corp; 1987.
46. Benton AL, Varney N, Hamsher KD. Visuospatial judgment: a clinical test. Arch Neurol. 1978;35:364-367.
FREE FULL TEXT
47. Goodglass H, Kaplan E. The Assessment of Aphasia and Related Disorders. Philadelphia, Pa: Lea & Febiger; 1972.
48. Ekstrom RB, French JW, Harman HH, Demen D. Manual for Kit of Factor-Referenced Cognitive Tests. Princeton, NJ: Educational Testing Service; 1976.
49. Cooper JA, Sagar HJ. Incidental and intentional recall in Parkinson's disease: an account based on diminished attentional resources. J Clin Exp Neuropsychol. 1993;15:713-731.
ISI
| PUBMED
50. Raven JC, Court JH, Raven J. Manual for Raven's Progressive Matrices and Vocabulary: Standard Progressive Matrices. Oxford, England: Oxford Psychologists Press; 1992.
51. Nelson HE. National Adult Reading Test (NART) Test Manual. Windsor, England: NFER-Nelson Publishing Co; 1982.
52. McKhann G, Drachman D, Folstein M, Katzman R, Price D, Stadlan EM. Clinical diagnosis of Alzheimer's disease: report of the NINCDS-ADRDA Work Group under the auspices of Department of Health and Human Services Task Force on Alzheimer's Disease. Neurology. 1984;34:939-944.
FREE FULL TEXT
53. Hixson JE, Vernier DT. Restriction isotyping of human apolipoprotein E by gene amplification and cleavage with HhaI. J Lipid Res. 1990;31:545-548.
ABSTRACT
54. Wenham PR, Price WH, Blandell G. Apolipoprotein E genotyping by one stage PCR. Lancet. 1991;337:1158-1159.
ISI
| PUBMED
55. Rose GA, Blackburn H, Gillum RF, Prineas RJ. Cardiovascular Survey Methods. Geneva, Switzerland: World Health Organization; 1982:162-165.
56. SAS II: SAS/STAT User's Guide, Version 8. Cary, NC: SAS Institute Inc; 2000.
57. Lee E, Forthofer R, Lorimor R. Analyzing Complex Survey Data. Beverly Hills, Calif: Sage Publications; 1989.
58. Bienias JL. Replicate-based variance estimation in a SAS macro. In: Proceedings of the Fourteenth Annual Meeting of the NorthEast SAS Users Group, Statistics, Data Analysis, and Econometrics Section; September 30-October 3, 2001; Baltimore, Md.
59. Morris MC, Evans DA, Bienias JL, Wilson RS, Tangney CC. Fish consumption and cognitive decline [abstract]. Am J Epidemiol. 2000;151:S93.
60. Lim S, Suzuki H. Changes in maze behavior of mice occur after sufficient accumulation of docosahexaenoic acid in brain. J Nutr. 2001;131:319-324.
FREE FULL TEXT
61. Su HM, Bernardo L, Mirmiran M, et al. Bioequivalence of dietary -linolenic and docosahexaenoic acids as sources of docosahexaenoate accretion in brain and associated organs of neonatal baboons. Pediatr Res. 1999;45:87-93.
ISI
| PUBMED
62. Iso H, Rexrode KM, Stampfer MJ, et al. Intake of fish and omega-3 fatty acids and risk of stroke in women. JAMA. 2001;285:304-312.
FREE FULL TEXT
63. Gillum RF, Mussolino ME, Madans JH. The relationship between fish consumption and stroke incidence: the NHANES I Epidemiologic Follow-up Study (National Health and Nutrition Examination Survey). Arch Intern Med. 1996;156:537-542.
FREE FULL TEXT
64. Keli SO, Feskens EJ, Kromhout D. Fish consumption and risk of stroke: the Zutphen Study. Stroke. 1994;25:328-332.
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