To determine the effect of varying dosing schedules and predictor variables on the seroprotection rates and geometric mean titer levels resulting from the hepatitis B vaccination series among adolescents.
Adolescents received the hepatitis B vaccination series at varying schedules according to their natural adherence patterns. Data collected included participants' medication use; chronic illness; use of cigarettes, alcohol, and marijuana; age; race/ethnicity; and body mass index. Participants' dates of vaccinations were recorded and titer levels for hepatitis B surface antibody were drawn ∼12 and 24 months after study enrollment. The data for 498 participants were analyzed using χ2 tests, Student t tests, logistic regression models, and analysis of variance.
Seroprotection rates among adolescents were not affected by late vaccinations. The only factors affecting the achievement of seroprotection ∼12 and 24 months after the first vaccination were body mass index and the number of immunizations received. Increased time between doses 1 and 2 and doses 2 and 3 showed a trend toward correlating with increasing titer levels.
Although adolescents at risk of acquiring hepatitis B should receive the hepatitis B vaccination series in a timely fashion, late doses are not detrimental, and may be beneficial, to achieving high antibody levels against the hepatitis B virus.