Table 1 Clinical characteristics of the participants stratified by coffee consumption
|  | Non-coffee (n = 818) | Coffee (n = 510) | Total (n = 1328) | P |
|---|---|---|---|---|
Male (n, %) | 330 (40.34%) | 210 (41.18%) | 540 (40.66%) | 0.763 |
Age, years (mean, SD) | 52.80 (14.22) | 48.34 (14.49) | 51.08 (14.47) | <  0.001 |
Weight, kg (mean, SD) | 65.07 (12.60) | 69.99 (14.24) | 66.95 (13.46) | <  0.001 |
BMI, kg/m2 (mean, SD) | 23.96 (3.65) | 25.18 (4.08) | 24.43 (3.87) | <  0.001 |
Waist, cm (mean, SD) | 86.46 (10.19) | 88.79 (11.07) | 87.35 (10.59) | <  0.001 |
Fat, % (mean, SD) | 28.37 (7.70) | 29.81 (8.25) | 28.91 (7.94) | 0.004 |
SBP, mmHg (mean, SD) | 130.39 (18.17) | 130.23 (17.41) | 130.33 (17.88) | 0.880 |
DBP, mmHg (mean, SD) | 79.02 (10.93) | 79.20 (11.33) | 79.09 (11.09) | 0.776 |
Diabetic family history (n, %) | 351 (44.94%) | 249 (50.82%) | 1271 (47.21%) | 0.041 |
Hypertension (n, %) | 279 (34.15%) | 160 (31.37%) | 1327 (33.08%) | 0.296 |
Dislipidemia (n, %) | 249 (30.48%) | 168 (33.01%) | 1326 (31.45%) | 0.335 |
Higher Education (n, %) | 370 (45.23%) | 312 (61.18%) | 1328 (51.36%) | <  0.001 |
Current smoke (n, %) | 104 (12.73%) | 91 (17.88%) | 1326 (14.71%) | 0.010 |
Current alcohol intake (n, %) | 115/703 (14.06%) | 107/402 (21.02%) | 222 (16.73%) | 0.001 |
Tea consumption (n, %) | 293 (35.91%) | 321 (62.94%) | 1326 (46.30%) | <  0.001 |
Frequent physical activity (n, %) | 629 (76.99%) | 385 (75.49%) | 1327 (76.41%) | 0.532 |
FPG, mmol/L (median, IQR) | 6.15 (5.46–7.06) | 6.04 (5.36–7.14) | 6.11 (5.42–7.08) | 0.259 |
PG30min, mmol/L (median, IQR) | 10.67 (9.09–12.38) | 10.47 (9.05–12.27) | 10.60 (9.07–12.35) | 0.188 |
PG1h, mmol/L (median, IQR) | 12.29 (9.79–15.25) | 12.19 (9.43–14.97) | 12.25 (9.68–15.14) | 0.148 |
PG2h, mmol/L (median, IQR) | 10.02 (7.36–14.31) | 9.53 (7.09–13.47) | 9.85 (7.28–14.06) | 0.024 |
PG3h, mmol/L (median, IQR) | 6.69 (4.84–9.62) | 6.30 (4.55–8.97) | 6.45 (4.74–9.35) | 0.016 |
FIN, uIU/mL (median, IQR) | 8.43 (5.75–12.61) | 10.10 (6.94–16.22) | 9.08 (6.02–13.81) | <  0.001 |
IN30min, uIU/mL (median, IQR) | 44.05 (27.52–69.97) | 58.09 (34.50–93.70) | 48.21 (28.82–80.23) | <  0.001 |
IN1h, uIU/mL (median, IQR) | 64.58 (40.18–101.45) | 77.03 (50.30–121.83) | 69.20 (44.25–107.50) | <  0.001 |
IN2h, uIU/mL (median, IQR) | 69.91 (45.83–115.70) | 81.54 (51.53–128.38) | 74.75 (48.05–119.05) | 0.002 |
IN3h, uIU/mL (median, IQR) | 32.22 (17.34–57.65) | 34.29 (18.23–62.04) | 32.75 (17.64–58.38) | 0.237 |
HbA1c, % (median, IQR) | 6.00 (5.60–6.50) | 5.90 (5.50–6.60) | 5.90 (5.60–6.50) | 0.855 |
GA, % (median, IQR) | 14.30 (12.80–16.60) | 13.85 (12.40–16.70) | 14.10 (12.70–16.68) | 0.263 |
Newly diagnosed diabetes (n, %) | 381 (46.58%) | 213 (41.76%) | 594 (44.73%) | 0.037 |
Impaired glucose regulation (n, %) | 237 (28.97%) | 148 (29.02%) | 385 (28.99%) | 0.241 |
HOMA-β (mean, SD) | 84.30 (89.77) | 104.65 (103.29) | 92.11 (95.66) | <  0.001 |
HOMA-IR (median, IQR) | 2.37 (1.49–3.71) | 2.80 (1.75–4.61) | 2.52 (1.60–4.04) | <  0.001 |
Stumvoll first phase (mean, SD) | 459.97 (1096.52) | 717.67 (1060.32) | 558.85 (1089.60) | <  0.001 |
Stumvoll second phase (mean, SD) | 179.32 (248.52) | 242.04 (246.55) | 203.33 (249.54) | <  0.001 |