Table 1.
Baseline patient characteristics expressed as tertiles of serum R-SH concentration.
| Overall N = 943 | Tertile 1 N = 310 | Tertile 2 N = 315 | Tertile 3 N = 318 | P-value | |
|---|---|---|---|---|---|
| R-SH, µM | 202 ± 48 | <181 (149 ± 25) | 181–227 (202 ± 13) | >227 (255 ± 21) | |
| Demographics | |||||
| Age, years | 65.0 ± 10.0 | 66.9 ± 9.6 | 64.9 ± 10.4 | 63.4 ± 9.8 | <0.001 |
| Diabetes duration, years | 6.5 [2.9–10.1] | 5.9 [2.9–9.8] | 6.4 [2.6–9.8] | 6.7 [3.4–10.6] | 0.543 |
| Male gender, n (%) | 517 (54.7) | 142 (45.8) | 179 (56.8) | 195 (61.3) | <0.001 |
| Current smoker, n (%) | 158 (16.7) | 53 (17.1) | 57 (18.1) | 48 (15.1) | 0.578 |
| BMI, kg/m2 | 29.3 [26.8–33.0] | 29.7 [27.1–33.9] | 29.7 [26.8–33.5] | 28.7 [26.2–32.0] | 0.001 |
| Systolic blood pressure, mm Hg | 135.6 [125.0–144.0] | 136.0 [128.0–144.0] | 134.0 [124.0–145.0] | 135.0 [125.0–142.0] | 0.488 |
| Diastolic blood pressure, mm Hg | 80.0 [71.0–83.0] | 80.0 [72.0–84.0] | 80.0 [70.0–82.0] | 80.0 [70.0–82.0] | 0.492 |
| Complications | |||||
| Microvascular complications, n (%) | 275 (29.2) | 101 (32.6) | 98 (31.1) | 76 (23.9) | 0.037 |
| Micro-albuminuria, n (%) | 117 (12.4) | 38 (12.3) | 40 (12.7) | 39 (12.3) | 0.982 |
| Macro-albuminuria, n (%) | 11 (1.3) | 5 (1.6) | 5 (1.6) | 2 (0.6) | 0.453 |
| Retinopathy, n (%) | 38 (4.0) | 19 (6.1) | 15 (4.8) | 4 (1.3) | 0.006 |
| Neuropathy, n (%) | 175 (18.5) | 66 (21.3) | 62 (19.7) | 47 (14.8) | 0.091 |
| Macrovascular complications, n (%) | 215 (22.7) | 77 (24.8) | 65 (20.6) | 72 (22.6) | 0.589 |
| Angina pectoris, n (%) | 81 (8.6) | 26 (8.4) | 29 (9.2) | 26 (8.2) | 0.593 |
| Myocardial infarction, n (%) | 82 (8.7) | 32 (10.3) | 26 (8.3) | 23 (7.2) | 0.330 |
| PTCA, n (%) | 50 (5.3) | 15 (4.8) | 18 (5.7) | 17 (5.3) | 0.729 |
| CABG, n (%) | 45 (4.8) | 19 (6.1) | 12 (3.8) | 14 (4.4) | 0.424 |
| TIA, n (%) | 29 (3.1) | 9 (2.9) | 12 (3.8) | 8 (2.5) | 0.470 |
| CVA, n (%) | 38 (4.0) | 15 (4.8) | 7 (2.2) | 16 (5.0) | 0.214 |
| Heart failure, n (%) | 25 (2.6) | 11 (3.5) | 10 (3.2) | 4 (1.3) | 0.115 |
| Laboratory Measurements | |||||
| HbA1c, % (mmol/mol) | 6.7 ± 0.7 (50 ± 9) | 6.8 ± 0.9 (51 ± 9) | 6.7 ± 0.8 (50 ± 9) | 6.5 ± 0.7 (48 ± 8) | <0.001 |
| eGFR (MDRD), ml/min/1.73 m2 | 73.0 [61.0–86.0] | 69.0 [60.0–81.0] | 73.0 [60.0–86.0] | 77.0 [66.0–90.0] | 0.528 |
| Total cholesterol, mmol/L | 4.3 [3.7–5.0] | 4.3 [3.6–4.9] | 4.4 [3.7–5.1] | 4.2 [3.7–4.8] | 0.138 |
| HDL cholesterol, mmol/L | 1.2 [1.0–1.5] | 1.2 [1.0–1.5] | 1.2 [1.0–1.5] | 1.3 [1.1–1.5] | 0.158 |
| Total cholesterol:HDL ratio | 3.4 [2.8–4.2] | 3.3 [2.8–4.3] | 3.6 [2.9–4.3] | 3.3 [2.7–3.9] | 0.002 |
| LDL cholesterol, mmol/L | 2.3 [1.8–2.9] | 2.2 [1.8–2.8] | 2.4 [1.9–3.0] | 2.2 [1.8–2.8] | 0.023 |
| Triglycerides, mmol/L | 1.5 [1.1–2.1] | 1.5 [1.1–2.2] | 1.6 [1.1–2.3] | 1.4 [1.0–1.9] | 0.060 |
| Albumine:creatinine ratio, mg/mmol | 0.8 [0.4–1.5] | 0.8 [0.4–1.5] | 1.0 [0.4–1.5] | 0.6 [0.2–1.4] | 0.104 |
| Medication | |||||
| Dietary measures only, n (%) | 182 (19.2) | 69 (21.9) | 67 (21.3) | 47 (14.8) | 0.042 |
| Oral blood glucose lowering drugs, n (%) | 741 (78.3) | 228 (73.5) | 245 (77.8) | 265 (83.3) | 0.012 |
| Metformin, n (%) | 707 (74.7) | 217 (70.0) | 230 (73.0) | 257 (80.8) | 0.006 |
| Sulfonylurea derivatives, n (%) | 261 (27.6) | 84 (27.1) | 86 (27.3) | 91 (28.6) | 0.899 |
| Thiazolinediones, n (%) | 10 (1.1) | 4 (1.3) | 5 (1.6) | 1 (0.3) | 0.263 |
| DDP4 inhibitors, n (%) | 35 (3.7) | 10 (3.2) | 16 (5.1) | 9 (2.8) | 0.281 |
| Insulin, n (%) | 123 (13.0) | 40 (12.9) | 35 (11.1) | 48 (15.1) | 0.331 |
| Antihypertensive drugs, n (%) | 799 (84.5) | 270 (87.7) | 269 (85.4) | 258 (81.1) | 0.070 |
| Diuretics, n (%) | 349 (36.9) | 125 (40.3) | 112 (35.6) | 112 (35.2) | 0.207 |
| Beta blockers, n (%) | 354 (37.4) | 111 (35.8) | 131 (41.6) | 111 (34.9) | 0.182 |
| Calcium antagonists, n (%) | 170 (18.0) | 60 (19.4) | 54 (17.1) | 56 (17.6) | 0.657 |
| RAAS blockers, n (%) | 514 (54.3) | 170 (54.8) | 170 (54.0) | 174 (54.7) | 0.855 |
| Cholesterol lowering drugs, n (%) | 752 (79.5) | 248 (80.0) | 242 (76.8) | 260 (81.8) | 0.288 |
| Antidepressive drugs, n (%) | 44 (4.7) | 12 (3.9) | 19 (6.0) | 13 (4.1) | 0.375 |
| Thrombocyte aggregation inhibitors, n (%) | 168 (17.8) | 47 (15.2) | 59 (18.7) | 62 (19.5) | 0.340 |
Data are presented as number (%), mean (SD) or median [IQR]. Significant (p < 0.05) values are emphasized in bold. HbA1c is expressed in both IFCC derived mmol/mol as DCCT derived %. Missing values: gender n = 2, HbA1c n = 4, total cholesterol n = 4, HDL-cholesterol n = 5, smoking n = 7. eGFR-MDRD n = 7, systolic blood pressue n = 11. Abbreviations: BMI, body mass index; MI, myocardial infarction; PTCA, percutaneous transluminal coronary angioplasty; CABG, coronary artery bypass grafting; TIA, transient ischemic attack; CVA, cerebral vascular event; HbA1c, glycated hemoglobin; eGFR, estimated glomerular filtration rate; HDL, high-density lipoprotein; LDL, high-density lipoprotein; DDP4, dipeptidyl peptidase 4; RAAS, renin-angiotensin-aldosterone system; R-SH total, free thiol groups.