HPV4 Vaccine Adverse events in Young Women

From Medscape Medical News

Adverse Events Minor in Young Women Taking HPV4 Vaccine

Ricki Lewis, PhD

April 6, 2012 — Adverse events from initial human papillomavirus vaccination (HPV4; Gardasil, Merck) are mild, according to a studypublished online January 9 in the Journal of Women's Health. Results also indicate that older women understand the role of the virus in elevating cervical cancer risk better than younger women.

HPV4 vaccination began in the United States in girls and women aged 9 to 26 years in June 2006. The manufacturer's direct-to-consumer marketing campaign, extensive media coverage, and efforts in some states to require vaccination for public school admission spread awareness of the vaccine and of the ability of certain subtypes of HPV to cause cervical cancer.

Data on adverse events have been limited to clinical trial results and reports to the US Food and Drug Administration and the US Centers for Disease Control and Prevention's Vaccine Adverse Events Reporting System. Both sources indicate pain at the injection site, nausea, and syncope as adverse effects of the vaccination.

Allison L. Naleway, PhD, from the Center for Health Research, Kaiser Permanente Northwest, Portland, Oregon, and colleagues conducted a survey and collected electronic medical record information for 899 young women, aged 11 to 26 years, who were receiving their first injection from Kaiser Permanente Northwest during an 8-month period in 2008. Mail and telephone contact began within 1 week after the first of the series of vaccinations.

The 50-item survey assessed knowledge about the virus, the vaccine, and adverse effects, and probed the relationships between participants and healthcare providers. "Such information could be used to design or focus interventions to improve HPV4 uptake and compliance with the three-dose HPV4 series and might identify opportunities for improved provider communication and education of vaccine recipients," the investigators write.

Their results echoed earlier findings. About three quarters (696 [78%]) of the participants reported pain at the injection site, with up to 11% of them recalling the pain as severe to very severe. The percentage of respondents reporting pain and pain intensity was inversely proportional to age. A third of respondents reported pain worse than that from other vaccinations. One hundred fifty-five participants (17%) reported bruising, and 127 (14%) experienced swelling. These effects were reported more frequently among those younger than age 18.

Eight women (1%) reported syncope after the first vaccination, and 133 (15%) reported presyncope. Receiving additional vaccines at the same time was associated with increased reporting of adverse events. Younger women were more likely to have received multiple vaccines.

The researchers evaluated responses by age: 11 to 12 years (preteenagers), 13 to 17 years (adolescents), or 18 to 26 years (adults). Younger participants were less aware of the relationships among HPV, abnormal Pap test results, and genital warts. The value of age also emerged in assessment of personal risk. Fifteen percent of preteenagers, 8% of teenagers, and 4% of adults strongly agreed or agreed that they were too young to get cervical cancer. Older respondents were also more likely to recall seeing a vaccine advertisement (86% vs 55% for oldest and youngest groups, respectively; P < .0001).

"Our study shows that age is an important factor influencing young women's experiences with the quadrivalent HPV vaccine," the researchers conclude. Limitations of the survey include the 27% response rate and the 9 cases in which parents refused to allow their daughters to participate.J Womens Health. Published online January 9, 2012. Abstract