Psychological stress linked to visceral adiposity
Psychological stress is associated with adiposity as shown by a neurobiological pathway involving the amygdala and bone marrow, suggests a study.
The metabolic activity of the amygdala (AmygA) was associated with baseline body mass index (standardized β, 0.15; p=0.01), visceral adipose tissue (VAT; β, 0.19; p=0.002) and VAT/subcutaneous adipose tissue ratio (β, 0.20; p=0.002). These associations persisted even after adjustments were made for age and sex.
AmygA also correlated with bone marrow activity (β, 0.15; p=0.01), which in turn correlated with VAT (β, 0.34; p<0.001). In addition, pain analysis revealed that increased bone marrow activity mediated the association between AmygA and baseline VAT (p=0.007). Furthermore, after adjusting for age, sex and baseline VAT, an association was found between AmygA and achieved VAT after 1 year (p=0.02).
“Future studies should test whether targeting this mechanism attenuates adiposity and its complications,” the authors said.
This study assessed whether higher AmygA, a neural centre involved in the response to stress, correlated with greater VAT volumes and whether this association was mediated by increased bone marrow activity.
Participants included 246 patients without active oncologic, cardiovascular or inflammatory disease who underwent clinical 18F-fluorodeoxyglucose positron emission tomography/computed tomography imaging at the Massachusetts General Hospital in Boston, US. VAT imaging was repeated approximately 1 year later in 68 patients.
The authors used validated methods to measure AmygA, haematopoietic tissue activity and adiposity volumes. The relationship of AmygA with baseline and follow-up VAT was the main outcome measure.
“Epidemiologic data link psychological stress to adiposity, [but] the underlying mechanisms remain uncertain,” the authors noted.