TABLE 5

Risk factors for insufficient or excessive serum vancomycin concentrations at 24 h of treatment (T3)

CharacteristicaValueb for patients with vancomycin concns (mg/liter) of:P value (<20 vs >20 mg of vancomycin/liter)bValuec for patients with vancomycin concns (mg/liter) of:P value (<30 vs >30 mg of vancomycin/liter)c
<20 (n = 29)>20 (n = 78)<30 (n = 85)>30 (n = 22)
Age56 (37–68)59 (49–71)0.0759 (47–72)59 (46–70)0.67
No. (%) male23 (79)54 (69)0.3163 (74)14 (64)0.35
Wt (kg)56 (65–75)59 (65–90)0.00775 (65–80)80 (65–95)0.12
Body mass index (kg/m2)24 (22–26)25 (15–27)0.0124 (22–28)28 (24–30)0.01
No. (%) with:
    Medical admission20 (69)49 (63)0.5654 (64)15 (68)0.69
    Corticosteroids7 (24)27 (35)0.3128 (33)6 (27)0.58
    Neutropenia1 (3)9 (12)0.238 (9)2 (9)0.51
    Organ transplant2 (7)15 (19)0.1715 (18)2 (9)0.51
    Cancer4 (14)13 (17)0.7213 (15)4 (18)0.99
    COPD/asthma5 (17)14 (18)0.9314 (17)5 (23)0.68
    Diabetes7 (24)16 (21)0.6918 (21)5 (23)0.58
    Heart disease7 (24)17 (22)0.7919 (22)5 (23)0.65
    CKD7 (24)24 (31)24 (28)7 (32)
    Liver cirrhosis0 (0)6 (8)0.995 (6)2 (9)0.81
APACHE II on admission20 (15–23)19 (13–24)0.9720 (14–23)19 (13–23)0.66
No. (%) in shock17 (59)41 (53)0.6346 (54)12 (55)0.97
No. (%) on mechanical ventilation18 (62)40 (51)0.3249 (58)9 (41)0.25
SOFA score on day 16 (3–9)7 (4–10)0.917 (4–9)6 (4–10)0.86
Daily dose of vancomycin (mg/kg)36.8 (25–42.6)28.2 (23.5–35.7)0.1933.8 (24.0–38.5)25.8 (25.0–40.0)0.98
Vancomycin concn (mg/liter) at T139 (33–45)46 (40–50)0.1242 (33–47)50 (46–59)0.001
No. (%) with respiratory infection15320.3239 (46)8 (36)0.86
uCrCL (ml/min)138 (73–178)64 (33–138)0.1397 (51–162)52 (23–82)0.02
  • a CKD, chronic kidney disease; T1, end of loading dose infusion; uCrCL, creatinine clearance measured on daily urine excretion.

  • b Obtained by univariate analysis. Multivariate analysis found body mass index (odds ratio [95% confidence interval], 0.87 [0.78 to 0.96]) and uCrCL (1.01 [1.00 to 1.02]) to be predictive of insufficient drug concentrations.

  • c Obtained by univariate analysis. Multivariate analysis found body mass index (odds ratio [95% confidence interval], 1.15 [1.02 to 1.29]), the vancomycin concentration at T1 (1.06 [1.01 to 1.10]), and uCrCL (0.98 [0.97 to 0.99]) to be predictive of excessive drug concentrations.