Department of Research & Evaluation News

Rulin C. Hechter, MD, PhD, is a scientist with the Kaiser Permanente Department of Research & Evaluation and has been conducting important research into vaccine uptake. Recently, Dr. Hechter concluded a study which found the uptake of the HPV4 vaccine among boys enrolled in Kaiser Permanente’s Southern California health plans increased tenfold following changes in guidelines from the Centers for Disease Control and Prevention (CDC) recommending routine use of the vaccine.

Human papillomavirus (HPV) is the most common sexually transmitted infection in the U.S. and it impacts both males and females. The CDC recommends the HPV vaccine as a safe and effective way to protect against some of the most common types of HPV and the health problems the virus can cause, including genital warts and cancers of the cervix, anus and throat.

The recommendation for the HPV4 vaccine for boys has gone through several changes over the years. In October 2009, the CDC’s Advisory Committee on Immunization Practices (ACIP) issued a permissive use recommendation, which meant the HPV4 vaccine can be given for males aged 9 to 26 to reduce the likelihood of acquiring genital warts. In 2011, ACIP issued a routine use recommendation for boys aged 11-12 years and, further, recommended that all boys aged 13-21 years who had not yet received the vaccine be vaccinated.

We asked Dr. Hechter to discuss the significance of the CDC guidelines and her research.

Q: Why is it important for boys to receive HPV4?

A: There is a general awareness regarding women and HPV, but many people don’t know that men are also susceptible to the cancers tied to HPV. Every year, more than 9,000 men are affected by cancers caused by HPV. This is why it’s important to ensure boys receive the HPV4 vaccine, particularly since research has shown that the HPV4 vaccine produces the highest immune response at ages 11-12 and it is most effective if given before exposure to the virus in preventing genital warts and cancers caused by HPV. I believe it is essential that primary care providers begin to educate young boys, as well as girls, and their parents about the risks associated with HPV and the preventative measures that are available.

Q: Can you tell us more about your recent study and how the vaccination rates increased following the CDC’s routine recommendation in 2011?

A: Our study found uptake of the HPV4 vaccine among boys enrolled in Kaiser Permanente’s Southern California health plans increased tenfold from 1.6 percent at the beginning of the study period in 2009 to 18.5 percent following the CDC recommending routine use of HPV4 in 2011.

We also found that following the CDC’s routine use recommendation in 2011, Hispanic, non-Hispanic black and Asian boys were generally more likely to initiate the HPV4 vaccine series, especially those from neighborhoods with lower-income and lower education attainment, compared to non-Hispanic white boys and those from high income families.

In addition, receiving the flu vaccine was one of the strongest predictors for HPV4 vaccination, with boys who have received the flu vaccine being 48 percent more likely to initiate the HPV4 vaccine series.

Finally, boys who had a pediatrician as their assigned primary care provider (PCP) had a higher uptake of the vaccine compared to those who either had a PCP from other specialties or had no assigned PCP.

Q: A: Our study findings mirror national HPV4 vaccine coverage rates in adolescent boys. The CDC estimated that 33.6 percent of boys ages 13-17 had received at least one dose of the HPV vaccine by 2013. This national data represents the cumulative vaccine coverage among adolescents, and our estimated vaccination rates represent the uptake of the vaccine among age eligible boys 9-17 years old during each observation period before and after the routine recommendation.

We’ve had success with HPV4 vaccination rates among adolescent girls, so as an integrated health care organization we know we can do well in this area. For example, Kaiser Permanente Southern California is ranked sixth when compared with other health plans in terms of HPV4 vaccination rates among this group, according to the National Committee of Quality Assurance, a nonprofit group that promotes national quality benchmarks among hundreds of commercial health plans. At the moment there is no equivalent NCQA measure for HPV4 vaccination rates for adolescent boys.

Q: There are many factors that potentially influence HPV4 vaccination rates among adolescents, including parents’ concerns that the vaccine would promote unsafe sexual behavior. In addition, according to the 2013 National Immunization Survey-Teen data, parents said that not receiving a healthcare provider’s recommendation for HPV vaccine was the number one reason for not vaccinating their sons. Although our study did not explore the types of conversations PCPs are having with patients and their parents, it is important to ensure PCPs are armed with the appropriate information and resources to be able to talk about the HPV4 vaccine and its benefits.

Q: Why were vaccination rates relatively higher among certain ethnicities and socioeconomic groups?

A: Numerous studies have found that vaccinate rates often vary by gender, race, ethnicity and socioeconomic status. Our study findings are similar to the observed higher initiation rates in Hispanic boys and boys who were eligible for the Vaccines for Children program from a national sample of adolescents.

The higher rates may also be due to a greater acceptance of HPV vaccine in these populations.

Going forward, targeted provider education and parent education-and more safety data-will play an important role in decision making for the HPV vaccine.

Q: How are Kaiser Permanente patients informed of the routine vaccine recommendations?

A: Kaiser Permanente implements a very proactive immunization policy and members are brought up to date for routine recommended vaccines at each clinic visit, not just preventive care visits.