Table 1

Basal patient characteristics at randomization. Lower extremity data are given only for index ulcer limb. Categorical variables are given as percent and continuous variables as medians and ranges

HBOTPlacebo
Number of patients4945
Age (years)69 (37–95)68 (28–86)n.s.
Females (%)2216n.s.
Smoking habits6169n.s.
    Current (%)2229n.s.
    Previous (%)4138n.s.
    Pack-years (nonsmokers excluded)26 (1–47)25 (4–73)n.s.
Mobility
    Walking without support (%)4344n.s.
    Walking with support (%)3831n.s.
    Wheelchair (%)1824n.s.
Diabetes duration (years)20 (1–63)23 (3–54)n.s.
Diabetes type 1/2 (%)24/7642/58n.s.
Glycated hemoglobin (%)*7.8 (4.2–11.0)8.1 (5.0–12.5)n.s.
Hemoglobin (g/l)127 (95–156)123 (95–160)n.s.
Creatinine (μmol/l)104 (52–804)101 (48–687)n.s.
C-reactive protein (mg/l)8 (1–161)7 (1–49)n.s.
Leukocyte count (109/l)8.5 (3.7–13.1)7.7 (1.9–13.8)n.s.
Concomitant diagnoses
    Hypertension (%)7673n.s.
    Hyperlipidemia (%)8887n.s.
    Myocardial infarction (%)2533n.s.
    Stroke (%)1616n.s.
    Congestive heart failure (%)3527n.s.
    Atrial fibrillation (%)2533n.s.
    Nephropathy (%)9080n.s.
    Dialysis (%)67n.s.
    Renal transplant (%)42n.s.
    Prior major amputation (%)147n.s.
    Prior minor amputation (%)3247n.s.
    Charcot foot (%)49n.s.
Medication
    Insulin (%)9091n.s.
    Metformin (%)1013n.s.
    Sulfonylurea (%)1216n.s.
    Statin (%)6960n.s.
    Aspirin (%)6356n.s.
    Clopidrogel (%)813n.s.
    Warfarin (%)1824n.s.
    ACE-inhibitor or ARB (%)6974n.s.
    β-blocker (%)3940n.s.
    Diuretics (%)6751n.s.
    Antibiotics, oral (%)6573n.s.
    Antibiotics, intravenous (%)00n.s.
Index ulcer size (cm2)3.1 (0.6–55)2.8 (0.6–39)n.s.
Ulcer duration (months)9 (3–44)10 (3–39)n.s.
Wagner classification
    Grade 1 (%)00n.s.
    Grade 2 (%)2427n.s.
    Grade 3 (%)5162n.s.
    Grade 4 (%)2411n.s.
    Grade 5 (%)00n.s.
Index ulcer location
    Toe (%)3547n.s.
    Plantar forefoot (%)2724n.s.
    Middle foot (%)1413n.s.
    Heel (%)167n.s.
    Malleoli (%)67n.s.
    Dorsal (%)20n.s.
Peripheral circulation
    Previous vascular surgery (%)5749n.s.
    Toe blood pressure (mmHg)50 (5–130)55 (15–160)n.s.
    Toe blood pressure ≤60 mmHg (%)5757n.s.
    Toe blood pressure ≤35 mmHg (%)3329n.s.
  • *Glycated hemoglobin recalculated to % in Diabetes Control and Complications Trial standard,

  • †above ankle amputation,

  • ‡angiotensin II receptor blocker. n.s., not significant.