Author + information
- Amorina Ishai,
- Brian Tung,
- Natasha Mamdani,
- Lisa Shin,
- Roger Pitman,
- Steven Grinspoon and
- Ahmed Tawakol
Background: Although epidemiological studies link emotional stress, obesity and increased cardiovascular disease risk, the mechanisms mediating those links remain unclear. We imaged the amygdala, a brain region critically involved in stress, to assess the relationship between regional brain activity and longitudinal imaging measures of adiposity.
Methods: Individuals without known CVD or active oncologic disorders, who underwent 18F-FDG PET/CT imaging, were studied. Using validated integrative PET/CT methods, amygdalar activity (AmygA) and arterial inflammation (Art-I) were assessed. CT imaging was employed to quantify visceral and subcutaneous adipose tissue volumes (VAT and SAT). Change in VAT was assessed in a subset of individuals using serial CT imaging. Relationships between AA, VAT, and arterial inflammation were evaluated using Pearson correlation and mediation (path) analysis.
Results: 246 individuals, age 55±13 (mean±SD) years, (41% male), were included. AmygA significantly associated with: BMI (r=0.15, p=0.014), VAT (r=0.194, p=0.002), VAT:SAT ratio (r=0.20, p=0.002), but not SAT (r=0.04, p=0.54). Additionally, Art-I associated with both VAT (r=0.29, p<0.001), and AmygA (r=0.19, p=0.002). Path analysis suggested that 26% of the association between AmygA and Art-I was mediated by increased VAT (p=0.015). Moreover, in 83 individuals with follow-up CT adipose measurements, initial AA associated with subsequent increase in VAT (B, [95%CI]): 43.1 [7.3, 78.1], p=0.019) over the next 354 +/- 128 days, an association that persisted after controlling for baseline BMI, age and gender (45.0 [8.4, 81.7], p=0.017), or for baseline VAT (42.8 [7.2, 78.4], p=0.019). No such association was seen between initial AA and change in either SAT or BMI.
Conclusions: In this first study to link regional brain activity to adiposity, AmygA was found to independently associate with VAT cross-sectionally, and change in VAT longitudinally. Further, AmygA linked to ArtI in part via a path that includes increased VAT. These findings provide novel insights into mechanisms linking chronic stress and VAT and also have implications for understanding atherosclerotic disease mechanisms in humans.
Poster Hall, Hall C
Saturday, March 18, 2017, 3:45 p.m.-4:30 p.m.
Session Title: Innovations in Cardiovascular Risk Assessment and Reduction
Abstract Category: 32. Prevention: Clinical
Presentation Number: 1235-066
- 2017 American College of Cardiology Foundation