ObjectivesObesity adversely inhibits antibody response to vaccination. Three doses of HPV4 may or may not provide adequate long term protection against HPV 16/18 in obese females. The aim of this study was to determine whether adherence to HPV4 vaccination in a safety net population was reduced with increasing body mass index (BMI).MethodsWe designed a historical prospective study evaluating the number and dates of HPV4 dosing that occurred from July 1, 2006 through October 1, 2009 by the demographic characteristics of the 10–26 year old recipient females. The defined dosing intervals were adapted from the literature and obesity categories were defined by the WHO.Results1240 females with BMI measurements received at least one dose of HPV4; 38% were obese (class I, II and III) and 25% were overweight. Females with normal BMI received on-time triplet dosing significantly more often than did the obese class II and III females (30% vs. 18%, p<0.001). Obese class II/III females have a significant 45% less chance of completing the on-time triplet HPV4 series than normal women (OR = 0.55, 95% CI: 0.37, 0.83). Pregnancy history has a significant influence on BMI and HPV4 dosing compliance in this safety net population where 71% had been gravid. Hispanic females were less likely to complete HPV4 dosing regardless of BMI (aOR = 0.39, 95% CI: 0.16, 0.95).ConclusionsObesity, as well as gravidity and Hispanic race, are risk factors for lack of HPV4 vaccine adherence among young females in a safety net population.

ObjectiveSafety net health care centers in the US serve vulnerable and underinsured females. The primary aim of this work was to determine if HPV4 dosing compliance differs between females who receive doses at rural vs. urban core safety net health care locations.MethodsFemales exclusively receiving health care in the Truman Medical Center (TMC) safety net system at the urban core and rural locations were identified by their HPV4 vaccine records. Dates and number of HPV4 doses as well as age, gravidity, parity and race/ethnicity were recorded from the electronic medical record (EMR). Appropriate HPV4 dosing intervals were referenced from the literature.Results1259 females, 10–26 years of age, received HPV4 vaccination at either the rural (23%) or urban core location (77%). At the rural location, 23% received three doses on time, equal to the 24% at the urban core. Females seen in the urban core were more likely to receive on-time doublet dosing than on-time triplet dosing (82% vs. 67%, p<0.001). Mistimed doses occurred equally often among females receiving only two doses, as well as those receiving three doses.ConclusionsCompliance with on-time HPV4 triplet dose completion was low at rural and urban core safety net health clinics, but did not differ by location.