Plasma omega-3 and saturated fatty acids are differentially related to pericardial adipose tissue volume across race/ethnicity: the Multi-ethnic Study of Atherosclerosis

Background: Pericardial adipose tissue (PAT) is a cardiometabolic risk factor influenced by race/ethnicity, inflammation, and metabolic dysfunction. Omega-3 fatty acids (FAs) and saturated FAs (SFAs) are known to affect these latter phenomena and may influence PAT accumulation. We aimed to determine whether plasma levels of these FAs are related to PAT volume and its rate of change over a median 3-year follow-up. Methods: Cardiac computed tomography assessed PAT in 6785 Multi-Ethnic Study of Atherosclerosis participants. Gas chromatography flame-ionization estimated plasma phospholipid FAs. Regression analyses estimated associations of FAs with PAT volume and its rate of change with adjustments for other risk factors. Race-interactions were tested. Results: In cross-section, top tertiles of omega-3 FAs and odd-chained SFAs were associated with 2.8 and 4.93 cm³ lower PAT volumes, respectively; race/ethnicity was a significant modifying variable (p < 0.002). Even-chained SFAs were associated with 3.5 cm³ greater PAT volume. With stratification by race/ethnicity, Chinese Americans in the top tertile of omega-3 FAs showed 10.5 cm³ greater PAT volume than those in the referent tertile. Black individuals in the top tertile of odd-chained SFAs showed 5.0 cm³ lower PAT compared to referents. Black and Chinese Americans in top tertiles of even-chained SFAs showed respective 3.7 and 5.9 cm³ greater PAT volumes compared to referents. Two associations were observed in prospective analyses among Caucasians; race interactions were non-significant. Conclusions: Cross-sectional and prospective findings provide inconclusive evidence as to whether plasma FAs are related to PAT in healthy individuals. Cohort studies with longer follow-up periods are warranted.