Higher RBC EPA + DHA corresponds with larger total brain and hippocampal volumes

Abstract

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 1 DHA (omega-3 index) level was correlated with 2.1 cm 3 larger brain volume (p 5 0.048). DHA was marginally correlated (p 5 0.063) with total brain volume while EPA was less so (p 5 0.11). There were no correlations between ischemic lesion volumes and EPA, DHA, or EPA 1 DHA. A 1 SD greater omega-3 index was correlated with greater hippocampal volume (50 mm 3 , p 5 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 5 0.034). Aging is associated with increased risk of dementia and cognitive impairment, with exponentially increasing prevalence expected in the next several decades. 1 Based on data from the Framingham study, a middle-aged woman in North America of European descent has approximately 20% risk of developing dementia of some type in her lifetime, which usually involves Alzheimer disease (AD). Conclusion:2 Reduced brain volume is an important part of the pathology of AD, and hippocampal atrophy is frequently observed before symptomatic impairment. Omega-3 fatty acids (FAs) from marine sources could have an important role in maintaining brain structure and function with advancing age. Approximately 30% to 40% of FAs in gray matter of the cortex are docosahexaenoic acid (DHA), 4 and this FA is particularly concentrated in synaptic membranes. 5 However, in white matter, DHA constitutes only 4% of total FAs. 6Patients with AD have been reported to have decreased serum, brain, and neuronal DHA and/or eicosapentaenoic acid (EPA) compared with controls without dementia. 7-11 DHA levels within plasma phosphatidylcholine, in the highest quartile, were associated with a 40% to 50%

[P3–317]: DHA BRAIN UPTAKE AND APOE4 STATUS: A PET STUDY WITH [1‐11C]‐DHA

“…We previously reported that lower plasma levels of DHA were significantly associated with lower entorhinal brain volumes in older cognitively healthy adults with increased brain amyloidosis [13]. Higher ω-3 content of red blood cells was also associated with a lower rate of hippocampal atrophy [31]. Atrophy of this brain region predicts progression to AD [32].…”

Cognitive Impairment Is Associated with a Low Omega-3 Index in the Elderly: Results from the KORA-Age Study

“…As such, the hippocampus, a region thought to govern verbal recall, is sensitive to age-associated brain atrophy in both healthy and impaired individuals [7,47]. As has been shown, the omega-3 index was positively related to brain and hippocampal volume [48], which plays an important role in memory function.…”

Occupational mercury exposure in association with prevalence of multiple sclerosis and tremor among US dentists

“…Investigators in studies involving fish consumption and the nervous system have found both harmful and protective effects, conditional on the amount of MeHg and omega-3 fatty acids in the fish consumed. 48,49 Furthermore, without proper adjustment, fatty acids in fish can mask the harmful effects of MeHg on the nervous system. 50 Investigators in some studies have found associations of high MeHg exposure from fish consumption and decreased performance on psychomotor tests, which are considered preclinical indicators for some types of tremor.…”