Dopamine transporter in obesity: a meta-analysis

ABSTRACT The brain plays a major role in controlling the desire to eat. This meta-analysis aimed to assess the association between dopamine transporter (DAT) availability, and obesity. We performed a systematic search of MEDLINE (from inception to November 2020) and EMBASE (from inception to November 2020) for articles published in English using the keywords “dopamine transporter,” “obesity,” and “neuroimaging”. Data were plotted for each radiopharmaceutical, and linear regression was used to describe the relationship between DAT ratio, and body mass index (BMI), spline curves were adopted to fit data between DAT ratio and BMI. Five studies including 421 subjects were eligible for inclusion in this study. Two studies with 123 I-FP-CIT, one with 99m Tc-TRODAT, one with 123 I-PE21, and one with 18 F-FP-CIT were included. DAT availabilities from ENC-DAT project were higher than those from PPMI database both for caudate nucleus, and putamen. As there might be the inter-study variability, we calculated DAT ratio, after dividing DAT availabilities of subjects with overweight/obese BMI with mean DAT availabilities of subjects with normal BMI. In conclusion, we have shown that DAT availability of subjects with overweight/obesity was not different from those with normal BMI.