Fasting hepatic glucose uptake is higher in men than women

Differences in glucose metabolism between men and women have previously been reported. Our purpose was to determine if there is a gender difference in fasting hepatic glucose uptake (MRglu). Fifty-five patients (44 men, 11 women) referred for routine PET/CT using the glucose tracer 2-deoxy-2-[F-18]fluoro-D-glucose (FDG), mainly for cancer, had dynamic imaging for 30 min immediately following injection. Hepatic FDG clearance (mL/min/100 mL) was measured as gradient divided by intercept from Patlak-Rutland graphical analysis using a volume of interest over the abdominal aorta to record input function. Hepatic MRglu was obtained by multiplication of clearance by blood glucose concentration. Hepatic steatosis was diagnosed as CT density ≤40 HU Mean (standard deviation) hepatic MRglu in 44 men was 2.30 (1.14) μmol/min/100 mL, significantly higher than in 11 women in whom it was 1.07 (1.35) μmol/min/100 mL (P = 0.003). CT density was 52 (12) HU in women compared with 45 (9) HU in men (P = 0.04), but there was no significant difference in blood glucose, BMI, or prevalence of recent chemotherapy (within 6 months preceding PET/CT). When patients were subdivided into those without hepatic steatosis (31 men/9 women), those without evidence of FDG-avid malignancy on PET/CT (15/6), and those without either (11/5), gender differences in hepatic MRglu remained highly significant, but there were no significant differences in CT density, blood glucose, BMI, or recent chemotherapy history. Despite this being a population of clinically referred patients, the results strongly suggest that fasting hepatic MRglu is higher in men than in women.