Endocrinology and Nutrition, 2 Nuclear Medicine, Clínica Universidad de Navarra, Pamplona, Spain.

Transcripción

1 717 Optimisation of metformin discontinuation in diabetic patients explored with 18F-FDG PET/CT B. Pérez-Pevida 1, L. Sancho Rodriguez 2, E.F. Guillén Valderrama 2, F.J. Escalada San Martín 1, M.J. García Velloso 2, E. Pascual Corrales 1, G. Gutiérrez Buey 1, M. Llavero Valero 1, J.C. Galofré Ferrater 1, J.A. Richter 2, J. Salvador Rodríguez 1 ; 1 Endocrinology and Nutrition, 2 Nuclear Medicine, Clínica Universidad de Navarra, Pamplona, Spain. Background and aims: It is known that metformin increases 18F-FDG PET/CT intestinal uptake and that it is reduced after its discontinuation for 3 days. The aim of this study was to determine if in patients with type 2 diabetes mellitus (T2D), 24 or 48 h metformin discontinuation could be useful to reduce 18F- FDG PET/CT intestinal uptake keeping patient s glucose levels (GL) in normal range and improving PET/CT quality. Materials and methods: 101 T2D patients referred to a 18F-FDG PET/CT study were included. Drug regimen included metformin in 81 patients (group A) and other oral antidiabetic drugs (OAD) in 20 patients (group B). 30 patients without T2D served as the control group (group C). Group A was divided in three subgroups: 31 patients (group A1) were taking metformin, 21 patients (group A2) were asked to discontinue metformin for 24 h before 18F-FDG PET/CT and the remaining 29 patients (group A3) were asked to discontinue metformin for 48 h. 18F-FDG PET/CT intestinal uptake was assessed both, qualitatively (normal, mild, moderate or intense) and semi-quantitatively, using SUVmax values and tissue-to-background ratio (TBR). Results were compared among the groups. GL were assessed before PET/CT performance in all patients. Results: Intense intestinal uptake in group A3 (17%) was significantly lower (p<0.001) than in group A2 (32%) and A1 (68%) and comparable to group B (15%) and C (7%). Intestinal 18F-FDG uptake in group A was reduced after metformin discontinuation for 24 hours (TBR A1 =2,32 vs TBR A2=3,24; p=ns) and significantly after 48 hours (TBR A3=1,82 vs A1 y A2; p<0.001). There were no significant differences among A3 (TBR=1, 82), B (TBR=1, 69) and C (TBR=1,40). There were also no significant differences in age and body mass index (BMI) among the different groups. GL were higher in group A (122±19) than in groups B (119±19) and C (95±11) (p<0. 01). Conclusion: Metformin discontinuation for 48 hours is feasible and better than 24 hours to reduce 18F- FDG intestinal uptake in T2D and it significantly improved PET/CT studies quality. Although GL increased with discontinuation, they were in normal range according to guidelines.