Table 1.
Baseline clinical and laboratory characteristics of the study population according to the AIP quartiles
| Variable | Q1 | Q2 | Q3 | Q4 | P value | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| n = 199 | n = 200 | n = 200 | n = 199 | Overall | Q2 vs. Q1 * | Q3 vs. Q1 * | Q3 vs. Q2 * | Q4 vs. Q1 * | Q4 vs. Q2 * | Q4 vs. Q3 * | |
| Demographics | |||||||||||
| Age (years) | 63 ± 8 | 63 ± 10 | 61 ± 9 | 58 ± 12 | < 0.001 | 0.750 | 0.051 | 0.498 | < 0.001 | < 0.001 | 0.007 |
| Male sex, n (%) | 125 (62.8) | 146 (73.0) | 153 (76.5) | 156 (78.4) | 0.002 | 0.029 | 0.003 | 0.420 | 0.001 | 0.209 | 0.651 |
| Clinical values (on admission) | |||||||||||
| BMI (kg/m2) | 25.3 ± 3.1 | 25.4 ± 2.8 | 26.1 ± 3.1 | 27.0 ± 3.5 | < 0.001 | 0.997 | 0.081 | 0.129 | < 0.001 | < 0.001 | 0.028 |
| SBP (mm Hg) | 133 ± 18 | 133 ± 17 | 130 ± 16 | 131 ± 16 | 0.116 | – | – | – | – | – | – |
| DBP (mm Hg) | 75 ± 11 | 76 ± 10 | 75 ± 10 | 77 ± 11 | 0.203 | – | – | – | – | – | – |
| Risk factors | |||||||||||
| Smoking status | |||||||||||
| Current smoking, n (%) | 60 (30.2) | 77 (38.5) | 76 (38.0) | 111 (55.8) | < 0.001 | 0.079 | 0.098 | 0.918 | < 0.001 | 0.001 | < 0.001 |
| Former smoking, n (%) | 33 (16.6) | 33 (16.5) | 38 (19.0) | 26 (13.1) | 0.455 | – | – | – | – | – | – |
| Never smoking, n (%) | 106 (53.3) | 90 (45.0) | 86 (43.0) | 62 (31.2) | < 0.001 | 0.099 | 0.040 | 0.687 | < 0.001 | 0.004 | 0.014 |
| Chronically daily drinking, n (%) | 14 (7.0) | 18 (9.0) | 26 (13.0) | 21 (10.6) | 0.234 | – | – | – | – | – | – |
| Family history of CHD, n (%) | 54 (27.1) | 60 (30.0) | 69 (34.5) | 56 (28.1) | 0.386 | – | – | – | – | – | – |
| Hypertension, n (%) | 138 (69.3) | 137 (68.5) | 141 (70.5) | 130 (65.3) | 0.715 | – | – | – | – | – | – |
| Dyslipidaemia, n (%) | 107 (53.8) | 174 (87.0) | 192 (96.0) | 195 (98.0) | < 0.001 | < 0.001 | < 0.001 | 0.001 | < 0.001 | < 0.001 | 0.245 |
| Previous MI, n (%) | 36 (18.1) | 43 (21.5) | 40 (20.0) | 51 (25.6) | 0.301 | – | – | – | – | – | – |
| Past PCI, n (%) | 47 (23.6) | 50 (25.0) | 50 (25.0) | 44 (22.1) | 0.891 | – | – | – | – | – | – |
| Previous ischemic stroke or TIA, n (%) | 13 (6.5) | 13 (6.5) | 17 (8.5) | 8 (4.0) | 0.338 | – | – | – | – | – | – |
| PAD, n (%) | 27 (13.6) | 29 (14.5) | 31 (15.5) | 33 (16.6) | 0.853 | – | – | – | – | – | – |
| Cardiac failure, n (%) | 12 (6.0) | 13 (6.5) | 23 (11.5) | 19 (9.5) | 0.156 | – | – | – | – | – | – |
| LVEF (%) | 64 (60–67) | 64 (60–68) | 65 (60–68) | 65 (59–68) | 0.963 | – | – | – | – | – | – |
| Clinical presentation | |||||||||||
| UAP, n (%) | 171 (85.9) | 153 (76.5) | 150 (75.0) | 153 (76.9) | 0.033 | 0.016 | 0.006 | 0.726 | 0.020 | 0.928 | 0.660 |
| NSTEMI, n (%) | 19 (9.5) | 28 (14.0) | 28 (14.5) | 25 (12.6) | 0.493 | – | – | – | – | – | – |
| STEMI, n (%) | 9 (4.5) | 19 (9.5) | 22 (11.0) | 21 (10.6) | 0.088 | – | – | – | – | – | – |
| Laboratory measurements (fasting state) | |||||||||||
| SCr (μmol/L) | 66.5 (59.3–73.6) | 69.2 (61.9–80.3) | 70.3 (62.2–81.3) | 71.5 (63.2–82.2) | < 0.001 | 0.041 | 0.023 | 1.000 | < 0.001 | 0.966 | 1.000 |
| UA (μmol/L) | 303.2 (271.7–347.2) | 321.3 (279.6–373.0) | 323.8 (282.5–386.0) | 368.5 (307.0–410.3) | < 0.001 | 0.376 | 0.011 | 1.000 | < 0.001 | < 0.001 | < 0.001 |
| TC (mmol/L) | 3.90 ± 0.96 | 4.06 ± 1.01 | 4.10 ± 0.99 | 4.47 ± 1.03 | < 0.001 | 0.341 | 0.179 | 0.984 | < 0.001 | < 0.001 | 0.002 |
| LDL-C (mmol/L) | 2.23 ± 0.85 | 2.48 ± 0.84 | 2.48 ± 0.77 | 2.53 ± 0.76 | 0.001 | 0.011 | 0.012 | 1.000 | 0.001 | 0.926 | 0.916 |
| HDL-C (mmol/L) | 1.23 ± 0.22 | 1.04 ± 0.17 | 0.95 ± 0.17 | 0.87 ± 0.14 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 |
| Triglycerides (mmol/L) | 0.88 (0.72–1.00) | 1.31 (1.18–1.48) | 1.71 (1.51–1.99) | 2.66 (2.25–3.38) | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 |
| FPG (mmol/L) | 6.80 (6.12–8.23) | 7.17 (6.32–8.25) | 6.80 (5.91–7.88) | 7.65 (6.61–8.49) | < 0.001 | 0.466 | 1.000 | 0.070 | 0.003 | 0.531 | < 0.001 |
| Glycated haemoglobin (%) | 7.0 (6.6–8.1) | 7.3 (6.7–8.2) | 7.2 (6.6–8.1) | 7.3 (6.7–8.0) | 0.409 | – | – | – | – | – | – |
| AIP | −0.1581 ± 0.1373 | 0.1029 ± 0.0482 | 0.2631 ± 0.0504 | 0.5272 ± 0.1773 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 |
* P < 0.0083 is considered statistically significant for post hoc multiple comparisons of categorical variables between groups
AIP Indicates atherogenic index of plasma; BMI Body mass index; SBP Systolic blood pressure; DBP Diastolic blood pressure; CHD Coronary heart disease; MI Myocardial infarction; PCI Percutaneous coronary intervention; TIA Transient ischemic attack; PAD Peripheral artery disease; LVEF Left ventricular ejection fraction; UAP Unstable angina pectoris; NSTEMI Non ST-segment elevation myocardial infarction; STEMI ST-segment elevation myocardial infarction; SCr Serum creatinine; UA Uric acid; TC Total cholesterol; LDL-C Low-density lipoprotein-cholesterol; HDL-C High-density lipoprotein-cholesterol; FPG Fasting plasma glucose