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Published on: May 29, 2020
Effect of needle length when immunizing obese adolescents with hepatitis B vaccine
Amy B Middleman1, Roberta Anding, Celestine Tung
1MSEd, Baylor College of Medicine, Texas Children's Hospital, 6621 Fannin St, Suite 1710.00, Houston, TX 77030, USA. amym@bcm.edu
Objective:
Several studies have noted that obese adolescents and adults achieve lower titers of antibody in response to vaccines such as hepatitis B virus (HBV) vaccine. The objective of this study was to determine whether use of a longer (1.5-in) rather than a standard (1-in) needle to penetrate the thicker deltoid fat pad among obese youth would result in higher antibody titers after immunization against HBV.
Methods:
Obese adolescents from a large metropolitan area who had not previously received the HBV vaccine were randomly assigned to be immunized with HBV vaccine by using either a 1-inch or a 1.5-inch needle.
Results:
Those who were immunized with a 1.5-inch needle achieved significantly higher antibody titers to hepatitis B surface antigen (median titers: 1-inch = 189.8 mIU/mL, 1.5-inch = 345.4 mIU/mL; P = .03).
Conclusions:
This finding supports the hypothesis that needle length accounts for a significant portion of the discrepancy in immune response to HBV vaccine that is seen among those with obesity.
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