Table 1 Characteristics of participants and study conditions of the three cohorts.
Young lean adults (N = 10) | Young overweight/obese adults (N = 10) | Middle-aged overweight/obese adults (N = 10) | |
|---|---|---|---|
Age (years) | 25 ± 3 | 22 ± 2 | 42 ± 6 |
Height (m) | 1.85 ± 0.05 | 1.78 ± 0.09 | 1.80 ± 0.05 |
Weight (kg) | 76.0 ± 7.3 | 92.9 ± 16.1 | 89.9 ± 7.6 |
BMI (kg/m2) | 22.2 ± 1.6 | 29.0 ± 3.4 | 27.8 ± 1.3 |
Waist-to-hip ratio | 0.87 ± 0.04 | 0.90 ± 0.08 | 0.96 ± 0.04 |
Fat mass (kg) | 13.4 ± 4.2 | 31.7 ± 9.7 | 24.7 ± 6.5 |
Lean body mass (kg) | 59.6 ± 5.9 | 56.2 ± 7.3 | 61.9 ± 5.1 |
Fasting glucose (mmol/l) | 4.2 ± 0.3 | 5.0 ± 0.4 | 4.7 ± 0.4 |
Study period | March 2013 to June 2013 | October 2015 to November 2016 | March 2015 to June 2016 |
Country | The Netherlands | Spain | The Netherlands |
Cooling methodology | 2 water-perfused blankets (Blanketrol III, Cincinnati USA) | 1 water-cooling vest (Polar Products Inc., Ohio, USA) with light cool air conditioned room. | 2 water-perfused blankets (Blanketrol III, Cincinnati USA) |
Time of cold exposure prior PET/CT scan | Shivering test + 2 h to individualized mild cold | Shivering test (48–72 h before) + 2 h to individualized mild cold | Shivering test + 2 h to individualized mild cold |
PET/CT scanner | Gemini TF64 PET/CT, Philips, Netherlands | Siemens Biograph 16 PET/CT, Siemens, Germany | Gemini TF64 PET/CT, Philips, Netherlands |
DEXA scan | Lunar iDXA, GE Healthcare, UK | QDR 4500 W, HOLOGIC, USA | Lunar iDXA, GE Healthcare, UK |
18F-FDG (MBq) | 152 ± 15 | 188 ± 11 | 107 ± 4 |
Ratio 18F-FDG (MBq) to BMI (kg/m2) | 6.8 ± 0.3 | 6.5 ± 0.8 | 3.8 ± 0.3 |
SUV lean body mass 1 threshold (g/ml) | 1.54 ± 0.09 | 1.98 ± 0.17 | 1.75 ± 0.15 |
SUVmean (g/ml) of descending aorta (reference tissue) | 1.18 ± 0.17 | 1.62 ± 0.23 | 1.66 ± 0.29 |
