In low-income populations, the rates of HPV vaccinations are low, two separate studies have found. They also identify vaccination barriers and tailored interventions that may help to increase HPV vaccine uptake rates.
Findings were presented at the American Association for Cancer Research Frontiers in Cancer Prevention Research Conference, held in Houston, Dec. 6-9, 2009.
Researchers at the University of California, Los Angeles (UCLA) found striking disparities in knowledge and awareness of HPV vaccines in different low-income minority groups.
"We expected some differences between the various ethnic groups, but not necessarily as many as we found," said Roshan Bastani, Ph.D., professor of health services and associate dean for research at the UCLA School of Public Health. She led the study, which was conducted through the Cancer Prevention Control Research Network (funded by the Centers for Disease Control and Prevention/National Cancer Institute).
Bastani and colleagues surveyed 390 mothers of girls aged 9 to 18 years who were registered with the Los Angeles County Office of Women's Health. Fifty-four percent of the participants were Latina, 20 percent were Chinese, 13 percent were Korean, 8 percent were black and 6 percent were of other ethnic origin.
Findings showed that vaccination rates were comparable to that of state and national estimates, however, there were significant gaps in the level of knowledge and awareness of HPV vaccine between ethnic groups.
- While 64 percent of respondents reported having heard of the HPV vaccine, among Koreans the rate was only 42 percent.
- Twenty-eight percent of the participating mothers reported knowing where to take their daughters to get the vaccine. This knowledge differed by ethnicity, with the lowest rates among Koreans (16 percent) and Chinese (19 percent) compared with blacks (29 percent) and Latinas (35 percent).
- Only 28 percent of participants said they had enough information to make an informed decision about HPV vaccination; Koreans (14 percent) and Chinese (17 percent) had the lowest rates compared with Latinas (31 percent) and blacks (56 percent).
- According to mothers of unvaccinated girls, barriers of HPV vaccination included concern over side effects, medical cost and insufficient information to make an informed decision.
"Now that we have found that there are ethnic differences, we have to be careful and not assume that a one size fits all intervention will be effective. We can tailor it per ethnicity and per the specific barriers identified," said Bastani.
Results of a separate study, which was also presented at the AACR Frontiers in Cancer Prevention Research Conference, showed that a lack of health care provider recommendation and poor uptake of the three-dose HPV vaccine series results in below average vaccination in low-income populations where the vaccine is readily available.
"We need interventions that help primary care teams to identify eligible patients and encourage the teen to receive all three doses. We need to take advantage of every opportunity where a teen comes into a clinic and offer all recommended adolescent vaccines," said Jasmin A. Tiro, Ph.D., assistant professor of clinical sciences at the University of Texas Southwestern Medical Center, Dallas.
Tiro and colleagues conducted this study at two neighborhood-based safety net clinics operated by the Parkland Health & Hospital System. The researchers examined the medical records of 353 female patients aged 11 to 18 years old, which is a more accurate method of assessing vaccine uptake than by using patient-provided information.
Results showed that 39.7 percent of eligible patients received a recommendation by their health care provider to receive the HPV vaccine. Of those patients, 24.3 percent refused the vaccine.
Overall, 30 percent of patients received the first dose of the vaccine in the series; only 6.5 percent completed all three doses required in the HPV vaccine series.
"We need to ensure that patients and their parents understand that the HPV vaccine is delivered in a series of three doses, which is unique among adolescent vaccines," said Tiro.
Based on the results of this study, the Parkland Health & Hospital System has adopted a new electronic medical records system that alerts their health care professionals if a patient is eligible for the HPV vaccine. Also, an automatic telephone system reminds the patient to keep clinic appointments and to receive their second and third HPV vaccine doses.