n-3 Fatty acids, hypertension and risk of cognitive decline among older adults in the Atherosclerosis Risk in Communities (ARIC) study.
OBJECTIVE
Recent research indicates that n-3 fatty acids can inhibit cognitive decline, perhaps differentially by hypertensive status.


METHODS
We tested these hypotheses in a prospective cohort study (the Atherosclerosis Risk in Communities). Dietary assessment using a food-frequency questionnaire and plasma fatty acid exposure by gas chromatography were completed in 1987-1989 (visit 1), while cognitive assessment with three screening tools--the Delayed Word Recall Test, the Digit Symbol Substitution Test of the Wechsler Adult Intelligence Scale-Revised and the Word Fluency Test (WFT)--was completed in 1990-1992 (visit 2) and 1996-1998 (visit 4). Regression calibration and simulation extrapolation were used to control for measurement error in dietary exposures.


METHODS
Four US communities--Forsyth County (North Carolina), Jackson (Mississippi), suburbs of Minneapolis (Minnesota) and Washington County (Maryland).


METHODS
Men and women aged 50-65 years at visit 1 with complete dietary data (n = 7814); white men and women in same age group in the Minnesota field centre with complete plasma fatty acid data (n = 2251).


RESULTS
Findings indicated that an increase of one standard deviation in dietary long-chain n-3 fatty acids (% of energy intake) and balancing long-chain n-3/n-6 decreased the risk of 6-year cognitive decline in verbal fluency with an odds ratio (95% confidence interval) of 0.79 (0.66-0.95) and 0.81 (0.68-0.96), respectively, among hypertensives. An interaction with hypertensive status was found for dietary long-chain n-3 fatty acids (g day-1) and WFT decline (likelihood ratio test, P = 0.06). This exposure in plasma cholesteryl esters was also protective against WFT decline, particularly among hypertensives (OR = 0.51, P < 0.05).


CONCLUSIONS
One implication from our study is that diets rich in fatty acids of marine origin should be considered for middle-aged hypertensive subjects. To this end, randomised clinical trials are needed.
Beydoun
May A
MA
Center for Human Nutrition, Department of International Health, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street E2610, Baltimore, MD 21205, USA. mbaydoun@jhsph.edu
Kaufman
Jay S
JS
Sloane
Philip D
PD
Heiss
Gerardo
G
Ibrahim
Joseph
J
D000368:Aged; D050197:Atherosclerosis / Q000150:complications; D003072:Cognition Disorders / Q000150:complications / Q000517:prevention & control*; D015331:Cohort Studies; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000145:classification / Q000150:complications*; D016015:Logistic Models; D008297:Male; D008396:Maryland; D008875:Middle Aged; D008910:Minnesota; D008922:Mississippi; D015999:Multivariate Analysis; D009657:North Carolina; D015596:Nutrition Assessment; D011446:Prospective Studies; D012307:Risk Factors; D014481:United States
D015525:Fatty Acids, Omega-3