Table 1.
Demographics and clinical features in the overall population and homocysteine quintiles
| Factor | All patients | Homocysteine subgroups (quintiles)–range (μmol/L) |
P-value | ||||
|---|---|---|---|---|---|---|---|
| Median (IQR) or n(%) | I (1.7–9.8) | II (9.9–12.5) | III (12.6–14.8) | IV (14.9–19.1) | V (19.2–92.3) | ||
| Demographics | |||||||
| Age (years) | 68 (59–74) | 65 (56–70) | 66 (55–71) | 69 (59–70) | 70 (59–76) | 71 (61–77) | 0.001 |
| Gender, male | 375 (70.6) | 59 (56) | 74 (69) | 79 (74) | 79 (74) | 84 (78) | 0.021 |
| Height (cms) | 168 (160–174) | 165 (160–171) | 168 (162–174) | 168 (160–173) | 168 (162–174) | 170 (161–175) | 0.179 |
| Weight (kg) | 73 (65–80) | 74 (53–83) | 74 (63–80) | 72 (66–79) | 75 (65–83) | 72 (65–80) | 0.317 |
| Past medical history | |||||||
| Hypertension | 220 (41.4) | 41 (39) | 41 (38) | 46 (43) | 46 (44) | 46 (43) | 0.182 |
| Diabetes mellitus | 57 (10.7) | 15 (14) | 6 (6) | 14 (13) | 7 (7) | 15 (14) | 0.939 |
| COPD | 21 (4.0) | 2 (2) | 5 (5) | 4 (4) | 3 (3) | 7 (6) | 0.146 |
| PVD | 48 (9.0) | 8 (8) | 10 (9) | 9 (9) | 11 (10) | 10 (9) | 0.128 |
| Heart failure | 1 (0.2) | 0 (0) | 0 (0) | 1 (1) | 0 (0) | 0 (0) | 0.895 |
| Prior cardiac surgery | 22 (4.1) | 2 (2) | 5 (4) | 4 (4) | 7 (7) | 4 (4) | 0.983 |
| Prior vascular surgery | 21 (4.0) | 1 (1) | 1 (1) | 7 (7) | 3 (3) | 9 (8) | 0.092 |
| Prior CVA | 15 (2.8) | 1 (1) | 4 (4) | 4 (4) | 2 (2) | 4 (4) | 0.408 |
| Chronic dialysis | 9 (1.7) | 1 (1) | 0 (0) | 1 (1) | 4 (4) | 3 (3) | 0.216 |
| Recent MI (<30 days) | 45 (8.5) | 13 (12) | 3 (3) | 8 (8) | 9 (9) | 12 (11) | 0.387 |
| Unstable angina | 30 (5.6) | 6 (6) | 10 (9) | 5 (5) | 3 (3) | 6 (6) | 0.176 |
| Pre-operative CHF | 16 (3.0) | 4 (4) | 1 (1) | 1 (1) | 4 (4) | 6 (6) | 0.301 |
| Pre-operative IABP | 1 (0.2) | 0 (0) | 0 (0) | 1 (1) | 0 (0) | 0 (0) | 0.895 |
| Left ventricular EF (%) | 54 (45–60) | 55 (50–60) | 55 (48–60) | 53 (45–60) | 53 (41–60) | 50 (38–57) | 0.001 |
| Serum creatinine (mg/dL) | 1 (0.8–1.2) | 0.8 (0.7–1.0) | 0.8 (0.8–1.0) | 1.0 (0.8–1.1) | 1.0 (0.8–1.2) | 1.2 (1.0–1.6) | 0.001 |
| Creatinine clearance (mL/min) | 75.5 (54.7–95.5) | 85 (71–105) | 88 (67–114) | 72 (58–91) | 72 (50–93) | 57 (34–86) | 0.001 |
| Haematocrit (%) | 39 (36–42) | 39 (36–42) | 40 (37–42) | 39 (35–42) | 40 (37–42) | 38 (34–42) | 0.110 |
| Homocysteine level (μmol/L) | 13.7 (10.5–17.4) | 8.3 (7–9) | 11.2 (11–12) | 13.8 (13–14) | 16.2 (16–17) | 24.2 (21–28) | 0.001 |
| Hyperhomocysteinaemia | 209 (39.4) | 0 (0) | 0 (0) | 0 (0) | 100 (96) | 109 (100) | 0.001 |
| EuroSCORE | 4 (2.1–7) | 3.1 (2–5) | 3.5 (2–7) | 4 (2–7) | 5 (3–7) | 6 (3–10) | 0.001 |
CHF, congestive heart failure; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular accident; EF, ejection fraction; IABP, intra-aortic balloon pump; IQR, interquartile range; MI, myocardial infarction; PVD, peripheral vascular disease.