Prevalence and Factors Associated with Brown Adipose Tissue Detected by 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Southern Chinese

Abstract

Objectives: This study aimed to evaluate the prevalence of brown adipose tissue, as detected by fluorine 18-fluorodeoxyglucose positron emission tomography combined with computed tomography (18F-FDG PETCT), in a Southern Chinese population. It also set out to determine associated factors with brown adipose tissue, and particularly its relationship with being overweight and having other metabolic disorders such as diabetes mellitus. Methods: We analysed 1765 consecutive 18F-FDG PET-CT scans of 1442 Chinese subjects for the presence of brown adipose tissue. Comparison of variables in subjects with positive and negative brown adipose tissue scans was performed using Student’s t test. The predictors of observed brown adipose tissue were analysed by multiple logistic regressions. Any p < 0.05 was considered statistically significant. Results: Brown adipose tissue was detected in 66 (4.6%) out of 1442 subjects. There were significant differences in age, gender, body mass index, blood glucose levels, and history of diabetes in subjects positive and negative for brown adipose tissue. In the multiple logistic regression test, age and mean monthly temperatures were both independent predictors of the presence of brown adipose tissue (p ≤ 0.001), which was itself a significant independent predictor of being overweight (p = 0.001). Conclusions: Age was the most important factor associated with the prevalence of brown adipose tissue in humans. Lower outdoor temperatures in winter can increase the prevalence of brown adipose tissue, even in subtropical climates. There was also an association of brown adipose tissue with being overweight and having higher blood sugar levels, supporting the notion that brown adipose tissue may be a potential therapeutic target for obesity and diabetes.