Vancomycin dosage in overweight and obese children.
OBJECTIVE
Vancomycin dosages in overweight and obese children were evaluated.


METHODS
This retrospective study evaluated data for children who were age 2-17 years, received i.v. vancomycin, and were admitted to a children's hospital from September 1, 2007, through October 31, 2009. Patients were then stratified into two groups: normal-weight patients and overweight or obese patients. The primary objective was to compare the number of vancomycin regimens between groups with a trough concentration of 5-15 μg/mL. Secondary objectives included a comparison of dosage changes and toxicities. Multivariate, conditional logistic regression was performed to assess the relationship between attaining optimal vancomycin concentrations (5-15 μg/mL) and independent variables.


RESULTS
Data were collected for 232 courses of vancomycin, representing 187 patients. The mean ± S.D. initial dose for the normal-weight and overweight or obese groups differed significantly (461.3 ± 303.1 mg and 658.4 ± 389.6 mg, respectively; p < 0.01); the milligram-per-kilogram initial vancomycin dose did not. The multivariate analysis revealed that every-eight-hour regimens had increased odds of achieving therapeutic concentrations (p < 0.001), while obese children had decreased odds of achieving therapeutic concentrations (p = 0.037).


CONCLUSIONS
A study of prescribing behavior in one hospital revealed no significant difference in the size of vancomycin doses (in milligrams per kilogram) given to normal-weight children compared with overweight or obese children. Regimens using every-eight-hour dosing were significantly more likely than other regimens to result in a vancomycin trough concentration of 5-15 μg/mL, and regimens for obese children, compared with regimens for nonobese children, were less likely to produce trough concentrations in the same range of 5-15 μg/mL.
Department of Pharmacy, Clinical and Administrative Sciences, College of Pharmacy, University of Oklahoma, Oklahoma City, 73117, USA.
Misty
M
Miller
Jamie L
JL
Miller
Tracy M
TM
Hagemann
Donald
D
Harrison
Susana
S
Chavez-Bueno
Peter N
PN
Johnson
D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D006776:Hospitals, Pediatric; D006801:Humans; D007262:Infusions, Intravenous; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications*; D050177:Overweight / Q000150:complications*; D012189:Retrospective Studies; D014640:Vancomycin / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000627:therapeutic use
D000900:Anti-Bacterial Agents; D014640:Vancomycin