Higher RBC EPA + DHA corresponds with larger total brain and hippocampal volumes: WHIMS-MRI study.
OBJECTIVE
To test whether red blood cell (RBC) levels of marine omega-3 fatty acids measured in the Women's Health Initiative Memory Study were related to MRI brain volumes measured 8 years later.


METHODS
RBC eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and MRI brain volumes were assessed in 1,111 postmenopausal women from the Women's Health Initiative Memory Study. The endpoints were total brain volume and anatomical regions. Linear mixed models included multiple imputations of fatty acids and were adjusted for hormone therapy, time since randomization, demographics, intracranial volume, and cardiovascular disease risk factors.


RESULTS
In fully adjusted models, a 1 SD greater RBC EPA + DHA (omega-3 index) level was correlated with 2.1 cm(3) larger brain volume (p = 0.048). DHA was marginally correlated (p = 0.063) with total brain volume while EPA was less so (p = 0.11). There were no correlations between ischemic lesion volumes and EPA, DHA, or EPA + DHA. A 1 SD greater omega-3 index was correlated with greater hippocampal volume (50 mm(3), p = 0.036) in fully adjusted models. Comparing the fourth quartile vs the first quartile of the omega-3 index confirmed greater hippocampal volume (159 mm(3), p = 0.034).


CONCLUSIONS
A higher omega-3 index was correlated with larger total normal brain volume and hippocampal volume in postmenopausal women measured 8 years later. While normal aging results in overall brain atrophy, lower omega-3 index may signal increased risk of hippocampal atrophy. Future studies should examine whether maintaining higher RBC EPA + DHA levels slows the rate of hippocampal or overall brain atrophy.
From the Department of Internal Medicine (J.V.P., W.S.H.), Sanford School of Medicine, University of South Dakota, Sioux Falls; Health Diagnostic Laboratory Inc. (J.V.P., W.S.H.), Richmond, VA; Department of Psychiatry (K.Y.), University of California Medical Center, San Francisco; Departments of Epidemiology and Internal Medicine (J.R., R.W.), University of Iowa College of Public Health, Iowa City; Department of Biostatistical Services (M.A.E.), Wake Forest School of Medicine, Winston-Salem, NC; and OmegaQuant Analytics (W.S.H.), Sioux Falls, SD.
James V
JV
Pottala
Kristine
K
Yaffe
Jennifer G
JG
Robinson
Mark A
MA
Espeland
Robert
R
Wallace
William S
WS
Harris
D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology; D015331:Cohort Studies; D004281:Docosahexaenoic Acids / Q000097:blood*; D015118:Eicosapentaenoic Acid / Q000097:blood*; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000639:trends*; D009929:Organ Size; D017698:Postmenopause / Q000097:blood; D016387:Women's Health / Q000639:trends*
D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid