Human papillomavirus vaccine and sexual activity: how do we best address parent and physician concerns?

Abstract

Comparedwithotherroutinelyrecommendedadolescentvaccines (eg, diphtheria and tetanus toxoids andacellular pertussis [Tdap] vaccine and quadrivalent meningococcal conjugate [MCV4] vaccine), human papillomavirus (HPV) vaccine uptake has been lower, with only 57% of adolescent females and 35% of adolescent males initiating the 3-dose HPVvaccine series.1Often, the reasons cited for these lowHPV vaccination rates pertain to the vaccine’s role in preventing a sexually transmitted infection (STI). Parents commonly indicate that they have not had their children vaccinated against HPV because the vaccine is not needed or because their child isnot sexually active,2 andevensomephysicians expresshesitancy toward strongly recommending the HPV vaccine. In a recently published series of qualitative interviews,3 physiciansexpressedconcernsaboutdiscussing sexual activitywith 11-and12-year-oldsand indicatedpreferences fordeferringvaccination to later ages.However, just aswedonotwait untilwe havebeen in the sun for 2hours to apply sunscreen,we should not wait until after an individual is sexually active to attempt to prevent HPV infection. Thehesitancyon thepart ofparents andphysicians tovaccinateordiscussvaccinationmaybeattributable toworries that HPV vaccinationwill be seen as a tacit approval for sexual activity. Concerns about increased sexual activity and risk disinhibitionhave beendiscussed since before the initial recommendation forHPVvaccination. In this issueof JAMA Internal Medicine, Jenaet al4 add to the literaturebypresenting anovel analysis that indicates no evidence for increased sexual activity after HPV vaccination. Jena et al evaluated STI-related insurance claims formore than200 000adolescent (aged12-18years) females insuredfrom January1,2005, throughDecember31,2010, intheUnitedStates. The researchersmatchedvaccinatedandunvaccinatedadolescents by age andkeyedonan indexquarter (quarter of theyear that included vaccination date for the vaccinated adolescents) for assessment of risk of STI claims. If analyseswere limited to onlydirectmeasuresofpostvaccinationSTI-relatedclaims, results couldbebiasedby longitudinal increases inSTI rateswith increasing age and potential selection bias related to prevaccinationdifferences inSTI riskamongHPVvaccine recipients.To accountfor thisbias, theresearcherscomputedoddsratios (ORs) for the association between the vaccine and sexual activity for 1-year periods before and after the index quarter and conductedadifference-in-differenceanalysisby taking the ratioof thepostvaccinationORrelative to theprevaccinationOR.Thus, the difference-in-difference OR of 1.05 (95% CI, 0.80-1.38) reported by Jena et al indicates that there was no increased risk ofSTI claimsamongHPVvaccinees relative tononvaccineesafter adjustment for preindex quarter STI risk.4 This patternwas consistent after stratification by age and restriction to adolescent females with insurance claims for contraceptives in their vaccine index quarter. These subanalyses indicate that even amongthosewhomayhavealreadybeensexuallyactive, sexual activity levels, as measured by incidence of STIs, did not increase after HPV vaccination. These findings should not come as a surprise to researchers in the field of HPV vaccinology and should serve as continuedreassurancethatHPVvaccinationdoesnot leadtosexual disinhibition. However, this reassurance leaves us with the question, “How can we use these findings to address concerns of anxious parents of adolescents?” Concerns about HPV vaccine are not always directly expressed in termsofpotential for increasing sexual activity;parentsoftenexpress concernsabout the recommendedageof the vaccine.According to the2013National ImmunizationSurvey– Teen, among parents of 13through 17-year-olds included in the survey who did not intend to have their children receive HPVvaccine in the next year, 15% indicated they believed the vaccine was not needed or not necessary, and 11% indicated their child was not sexually active.2 These concerns overlook the 3major reasonswhyHPV vaccine is recommended for 11and 12-year-olds. First, the antibody response in younger adolescents (9-15 yearsofage) isgreater forallHPVtypes in thequadrivalentHPV vaccine than it is in older adolescents and young adults (16-26 years of age).5 Second, estimates from the 2006-2010National Survey of Family Growth indicate that, by 15 through 17 years of age, 27% of adolescents in the United States have ever had sexual intercourse; by 18 through 19 years of age, this proportion increases to 63%.6 Third, with the Tdap and MCV4 vaccines also recommended for 11and 12-year-olds, health care professionalscanleveragethewell-childvisit for11-and12-yearolds recommended by the American Academy of Pediatrics to administertheTdapandMCV4vaccinesandinitiatetheHPVvaccine series, reducingmissed opportunities for vaccination.2 It is not just parentswhoneed this information, however. Physicianshave indicated reluctance to recommendHPVvaccinewith the sameemphasisused for theTdapandMCV4vaccines, citing concerns about discussing sexual activity or lack ofperceivedsusceptibilityofHPV infectionorHPV-relateddiseasesamong11and12-year-olds.3Weoften thinkof theHealth Belief Model constructs (perceived susceptibility and perceived severity) as they relate to an individual’s choice to elect apreventivevaccination.However, these constructs alsoneed to be considered in terms of physicians’ perceptions of their patients’ riskofdisease.Fromqualitative interviewswithphysicians, Perkins et al3 highlighted physician concerns, including, “I don’t get as scaredof cervical cancer just because... the Related article page 617 Research Original Investigation STIs After HPV Vaccination