Table 1.
Clinical Characteristics
| Quartiles of Baseline Hemoglobin |
P Value | ||||
|---|---|---|---|---|---|
| I (Lowest) (5.5−13.2 g/dL) (n = 210) | II (13.3−14.3 g/dL) (n = 223) | III (14.4−15.2 g/dL) (n = 205) | IV (Highest) (15.3−18.2 g/dL) (n = 192) | ||
| Age, y | 64.2 ± 9.7 | 61.9 ± 9.6 | 59.9 ± 8.9 | 56.1 ± 8.7 | <0001 |
| Male | 67 (31.9) | 99 (44.4) | 142 (69.3) | 123 (64.1) | <0.001 |
| Systolic blood pressure, mm Hg | 126.1 ± 16.1 | 124.5 ± 16.2 | 122.8 ± 15.4 | 125.1 ± 16.4 | 0.285 |
| Diastolic blood pressure, mm Hg | 75.5 ± 10.2 | 76.3 ± 10.3 | 76.3 ± 10.0 | 77.7 ± 11.6 | 0.288 |
| Body mass index, kg/m2 | 24.3 ± 3.1 | 24.5 ± 3.0 | 25.3 ± 3.2 | 25.6 ± 2.6 | <0.001 |
| Traditional risk factors | |||||
| Hypertension | 135 (65.2) | 135 (60.5) | 105 (51.5) | 95 (49.5) | 0.003 |
| Diabetes | 57 (27.5) | 44 (19.7) | 40 (19.6) | 28 (15.1) | 0.020 |
| Hyperlipidemia | 64 (30.8) | 74 (33.2) | 70 (34.3) | 62 (32.3) | 0.889 |
| Overweight or obesity | 81 (38.9) | 85 (38.6) | 102 (50.5) | 99 (53.8) | 0.002 |
| Current smoking | 16 (7.7) | 23 (10.3) | 53 (26.0) | 48 (25.0) | <0.001 |
| Family history of coronary artery disease | 55 (26.2) | 65 (29.1) | 66 (32.2) | 58 (30.2) | 0.597 |
| Cerebrovascular disease | 22 (10.7) | 17 (7.7) | 14 (6.9) | 10 (5.2) | 0.210 |
| Peripheral arterial disease | 6 (2.9) | 3 (1.4) | 3 (1.5) | 0 (0.0) | 0.115 |
| Medication | |||||
| Aspirin | 119 (56.9) | 99 (44.4) | 89 (43.4) | 77 (40.1) | 0.004 |
| Beta-blocker | 85 (40.7) | 67 (30.0) | 56 (27.3) | 51 (26.8) | 0.008 |
| ACE inhibitor/ARB | 87 (41.6) | 70 (31.4) | 61 (29.8) | 50 (26.3) | 0.007 |
| Statin | 98 (47.6) | 94 (42.9) | 80 (40.6) | 85 (45.0) | 0.539 |
| Laboratory | |||||
| Total cholesterol, mg/dL | 171.3 ± 37.8 | 186.2 ± 39.5 | 186.1 ± 39.5 | 188.3 ± 36.2 | <0.001 |
| Triglyceride, mg/dL | 125.5 ± 70.9 | 138.0 ± 93.9 | 140.6 ± 83.0 | 153.1 ± 80.6 | 0.013 |
| High-density lipoprotein cholesterol, mg/dL | 48.5 ± 13.4 | 49.5 ± 11.9 | 48.4 ± 12.9 | 47.8 ± 11.3 | 0.572 |
| Low-density lipoprotein cholesterol, mg/dL | 103.4 ± 32.1 | 114.0 ± 34.0 | 114.7 ± 34.9 | 115.8 ± 32.9 | 0.001 |
| Glucose, mg/dL | 109.3 ± 37.8 | 105.3 ± 30.4 | 109.1 ± 29.9 | 107.0 ± 28.7 | 0.526 |
| Creatinine, mg/dL | 1.1 ± 1.2 | 0.9 ± 0.2 | 1.0 ± 0.2 | 1.1 ± 0.2 | 0.043 |
| Hemoglobin, g/dL | 12.0 ± 1.5 | 13.8 ± 0.3 | 14.8 ± 0.3 | 16.0 ± 0.6 | <0.001 |
| Δ Hemoglobin, g/dL | 0.5 ± 1.7 | 0.0 ± 1.1 | −0.1 ± 1.0 | −0.6 ± 1.0 | <0.001 |
Values are mean ± SD or n (%).
Δ hemoglobin = hemoglobin level changes; ACE = angiotensin-converting enzyme; ARB = angiotensin receptor blocker.