Anthropometric and metabolic characteristics of study subjects stratified according to glucose tolerance
| Variables | Whole study group | NGT with 1 h glucose <155 mg/dL (95% CI) (1) | NGT with 1 h glucose ≥155 mg/dL (95% CI) (2) | Isolated IFG (95% CI) (3) | IGT (95% CI) (4) | p Value | p Value | ||
|---|---|---|---|---|---|---|---|---|---|
| 1 vs 2 | 1 vs 3 | 1 vs 4 | |||||||
| N (male/female) | 710 (345/365) | 295 (118/177) | 109 (64/45) | 104 (62/42) | 202 (101/101) | <0.0001 | 0.001 | 0.0008 | 0.03 |
| Age (year) | 50±13 (49 to 51) | 44±13 (42 to 46) | 51±12## (48 to 53) | 56±10 (54 to 58) | 54±12 (52 to 56) | <0.0001* | <0.0001* | <0.0001* | <0.0001* |
| BMI (kg/m2) | 30.5±6.2 (30.0 to 30.9) | 29.3±6.1 (28.6 to 30.1) | 31.0±6.1# (29.8 to 32.2) | 30.5±5.3 (29.1 to 31.1) | 32.1±6.4 (31.0 to 32.9) | <0.0001 | 0.02 | 0.30 | <0.0001 |
| Waist circumference (cm) | 102±14 (101 to 104) | 99±13 (97 to 101) | 103±12 (100 to 105) | 103±13 (100 to 106) | 106±14 (104 to 108) | <0.0001 | 0.17 | 0.15 | <0.0001 |
| Fat mass (%) | 33±9 (32 to 34) | 31±8 (30 to 32) | 33±9 (30 to 34) | 33±8 (31 to 34) | 35±8 (33 to 36) | <0.0001 | 0.29 | 0.09 | <0.0001 |
| Current smokers (n) | 145 (20.4%) | 67 (22.7%) | 25 (22.9%) | 17 (16.3%) | 36 (17.8%) | 0.35 | 0.92 | 0.21 | 0.22 |
| SBP (mm Hg) | 131±17 (130 to 133) | 128±17 (126 to 130) | 132±16 (128 to 135) | 136±15 (133 to 139) | 134±16 (131 to 136) | 0.61 | 0.92 | 0.97 | 0.90 |
| DBP (mm Hg) | 81±11 (80 to 82) | 80±11 (79 to 82) | 81±10 (80 to 83) | 82±10 (80 to 84) | 81±10 (79 to 82) | 0.73 | 0.97 | 0.94 | 0.95 |
| Fasting glucose (mg/dL) | 93±11 (93 to 94) | 87±7 (86 to 88) | 90±7### §§§ (89 to 91) | 107±6 §§§ (105 to 109) | 98±11 (97 to 100) | <0.0001 | 0.31 | <0.0001 | <0.0001 |
| 1 h glucose (mg/dL) | 153±44 (150 to 157) | 116±24 (113 to 119) | 180±21### § (176 to 184) | 157±36§§§ (150 to 164) | 191±35 (186 to 196) | <0.0001 | <0.0001 | <0.0001 | <0.0001 |
| 2 h glucose (mg/dL) | 123±34 (121 to 126) | 101±18 (99 to 103) | 113±20§§§ (109 to 117) | 111±21§§§ (106 to 115) | 168±21 (165 to 171) | <0.0001 | <0.0001 | 0.01 | <0.0001 |
| Fasting insulin (μU/mL) | 13±8 (12 to 14) | 12±8 (11 to 13) | 13±8§ (12 to 14) | 13±6 (12 to 14) | 14±8 (13 to 16) | <0.0001 | 0.05 | 0.001 | <0.0001 |
| 1 h insulin (μU/mL) | 110±76 (103 to 116) | 93±72 (84 to 102) | 145±92# § (126 to 164) | 111±70 (96 to 127) | 114±70 (103 to 125) | <0.0001 | <0.0001 | 0.006 | <0.0001 |
| 2 h insulin (μU/mL) | 95±81 (89 to 102) | 68±57 (61 to 75) | 96±69§§§ (81 to 110) | 83±62§§§ (70 to 97) | 142±102 (127 to 158) | <0.0001 | <0.0001 | 0.003 | <0.0001 |
| Total cholesterol (mg/dL) | 203±39 (200 to 206) | 200±37 (196 to 204) | 205±30 (200 to 211) | 212±40 (204 to 220) | 203±43 (197 to 209) | 0.88 | 0.99 | 0.99 | 0.99 |
| HDL (mg/dL) | 51±14 (49 to 52) | 52±14 (50 to 54) | 47±12 (45 to 50) | 52±13§ (50 to 55) | 48±14 (47 to 51) | 0.004 | 0.02 | 0.65 | 0.006 |
| Triglycerides (mg/dL) | 132±6) (127 to 138) | 120±63 (112 to 127) | 134±64 (122 to 147) | 140±63 127 to 152) | 147±78 (136 to 158) | 0.002 | 0.05 | 0.02 | <0.0001 |
| IGF-1 (ng/mL) | 158±61 (153 to 163) | 178±67 (170 to 186) | 152±54 (142 to 165) | 156±51 (143 to 168) | 138±50 (130 to 146) | 0.001 | 0.02 | 0.07 | <0.0001 |
| hsCRP (mg/L) | 3.7±3.3 (3.2 to 4.1) | 2.9±2.5 (2.5 to 3.5) | 4.1±3.4## (3.3 to 4.9) | 2.7±2.5 §§ (2.0 to 3.5) | 4.0±3.0 (3.5 to 4.5) | <0.0001 | <0.0001 | 0.61 | <0.0001 |
| ALT (UI/L) | 25±14 (24 to 26) | 22±13 (21 to 24) | 27±13 (23 to 39) | 25±11 (22 to 27) | 28±16 (26 to 31) | <0.0001 | 0.03 | 0.08 | <0.0001 |
| AST (UI/L) | 22±8 (21 to 23) | 20±7 (19 to 21) | 21±6 (20 to 22) | 22±7 (21 to 24) | 24±9 (23 to 25) | 0.001 | 0.83 | 0.12 | 0.001 |
| GGT (UI/L) | 26±18 (25 to 28) | 23±15 (21 to 25) | 31±24 (26 to 34) | 28±16 (24 to 32) | 33±31 (26 to 32) | 0.001 | 0.04 | 0.36 | <0.0001 |
| ALK (UI/L) | 69±20 (67 to 71) | 66±19 (63 to 68) | 72±18 (68 to 76) | 71±20 (67 to 76) | 71±21 (68 to 74) | 0.17 | 0.18 | 0.35 | 0.21 |
| Liver IR index | 2.73±0.37 (2.69 to 2.76) | 2.63±0.38 (2.58 to 2.68) | 2.82±0.36# (2.74 to 2.89) | 2.69±0.31 (2.62 to 2.76) | 2.84±0.34 (2.79 to 2.89) | <0.0001 | <0.0001 | 0.01 | <0.0001 |
| NAFLD (n) | 147 (49.8%) | 147 (49.8%) | 68 (62.4%) | 52 (50%) | 135 (66.8%) | 0.001 | 0.03 | 0.92 | 0.0002 |
Data are means±SD. Fasting, 1 h and 2 h insulin, and triglycerides were log transformed for statistical analysis, but values in the table represent a back transformation to the original scale. Categorical variables were compared by χ2 test. Comparisons between the four groups were performed using a general linear model with a post hoc Bonferroni correction for multiple comparisons. p Values refer to results after analyses with adjustment for age, gender, and BMI.
§p<0.05 vs IGT; §§p<0.001 vs IGT; §§§p<0.0001 vs IGT.
#p<0.05 vs IFG; ##p<0.001 vs IFG; ####p<0.0001 vs IFG.
*p Values refer to results after analyses with adjustment for gender.
ALK, alkaline phosphatase; ALT, Alanine aminotransferase; AST, aspartate aminotransferase; BMI, body mass index; DBP, diastolic blood pressure; GGT, γ-glutamyltransferase; HDL, high-density lipoprotein; hsCRP, high sensitivity C reactive protein; IFG, impaired fasting glucose; IGT, impaired glucose tolerance; IR, insulin resistance; NAFLD, non-alcoholic fatty liver disease; NGT, normal glucose tolerance; SBP, systolic blood pressure.