Brain emotional neural activity evaluated by 18F-FDG PET/CT is associated with osteoporosis in postmenopausal women

초록

Objectives: Emotional stress is well-known to contribute to the progression of post-menopausal osteoporosis. However, the underlying mechanism of stress-related brain emotional neural activity with osteoporosis is not fully investigated. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is a non-invasive imaging modality to evaluate the metabolic activity of amygdala, a region related with stress response. The aim of this study was to assess the association between metabolic activity of amygdala (AmygA) and osteoporosis in postmenopausal women. Materials and methods: A total of 115 postmenopausal women who underwent routine health check-up were enrolled in this study. They all underwent dual-energy X-ray absorptiometry and 18F-FDG PET/CT. Osteoporosis was defined as bone mineral density (BMD) T-score <= -2.5 at either lumbar spine or femoral neck. AmygA was defined as the maximum standardized uptake value (SUVmax) of amygdala divided by the mean SUV of temporal lobe. The levels of emotional stress were measured using the Psychosocial Well-being Index-Short Form (PWI-SF). Results: The women with osteoporosis showed significantly higher AmygA than without osteoporosis (0.81 +/- 0.16 vs. 0.61 +/- 0.13, p < 0.001). The AmygA value of 0.69 was proposed as an optimal cut-off value to predict participant with osteoporosis (sensitivity; 79.1%, specificity; 83.3%, area under the curve; 0.841, p < 0.001). Further multivariate anal-ysis showed that AmygA was significantly associated with osteoporosis in postmenopausal woman by multivariate analysis. Psychological stress scale (PWI-SF) showed significant positive correlation with AmygA and AmygA was highest in high stress risk-, intermediate in moderate stress risk-, and lowest in healthy group. Notably, there was a stepwise increase in associations between AmygA and osteoporosis from the healthy group to the moderate risk of stress- and the high risk of stress group. Conclusions: AmygA evaluated by 18F-FDG PET/CT is associated with osteoporosis in postmenopausal women. This study provides the novel insight that stress-related neurobiological activity involving amygdala could be associated with postmenopausal osteoporosis.