By Rebecca H. Allen, MD, MPH

Associate Professor, Department of Obstetrics and Gynecology, Warren Alpert Medical School of Brown University, Women and Infants Hospital, Providence, RI

Dr. Allen reports she is a Nexplanon trainer for Merck, and has served as a consultant for Bayer and Pharmanest.

SYNOPSIS: In this U.S. cross-sectional survey, the prevalence of genital human papillomavirus (HPV) infection in adult men was 45%, of which 25% were high-risk subtypes. The overall rate of HPV vaccination among those who were eligible was 11%.

SOURCE: Han JJ, Beltran TH, Song JW, et al. Prevalence of genital human papillomavirus infection and human papillomavirus vaccination rates among US adult men. National Health and Nutrition Survey (NHANES) 2013-2014. JAMA Oncol 2017; Jan 19. doi: .10.1001/jamaoncol.2016.6192. [Epub ahead of print].

The National Health and Nutrition Examination Survey (NHANES) is a national cross-sectional survey conducted by the CDC. The survey oversamples targeted populations (Hispanics, non-Hispanic blacks, Asians, older adults, and low-income persons) to ensure national representation. A total of 1,868 men 18-59 years of age participated in a home interview reporting demographics, educational level, household income, sexual history, tobacco use, circumcision status, and human papillomavirus (HPV) vaccination.

Participants self-collected a penile swab from the glans, and the swabs were sent to the CDC for HPV genotyping. Of these samples, 111 were inadequate, and those subjects were excluded from the HPV infection analysis.

The overall prevalence of genital HPV infection for men 18-59 years of age was 45.3% (95% confidence interval [CI], 41.3-49.3%), of which 25.1% (95% CI, 23-27.3%) were high-risk HPV subtypes. Infection peaked among men 28-32 years of age and again among men 58-59 years of age.

The prevalence of HPV 6, 11, 16, and 18 found in the 4-valent vaccine was 2.7%, 0.2%, 4.3%, and 1.7%, respectively. The prevalence of the other five HPV subtypes (31, 33, 45, 52, and 58) found in the 9-valent vaccine was 1.3%, 1.3%, 2.1%, 2.7%, and 1.3%, respectively. There was no difference in the proportion of men infected with these strains who were vaccine-eligible and vaccine-ineligible.

In a multivariable analysis, demographic factors associated with high-risk HPV infection were high school education (compared to less than high school) and men who were never married, living with a partner, or widowed, divorced, or separated from a spouse (compared to married men). Race, smoking, and circumcision status did not seem to influence HPV infection.

Age at first intercourse of > 18 years of age was protective against HPV infection (odds ratio, 0.5; 95% CI, 0.3-1.0) compared to coitarche at < 16 years of age. The overall rate of HPV vaccination among those who were eligible was 10.7% (95% CI, 7.8-14.6%).

COMMENTARY

HPV is the most common sexually transmitted infection in the United States.1 A similar NHANES study demonstrated that the overall prevalence of HPV among U.S. women was 27% based on vaginal swabs.2 The authors conducted this study to obtain more data on the U.S. population prevalence of HPV infection in men.

Although the focus of HPV prevention has been on cervical cancer, more than 9,000 HPV-related cancers occur in men annually, accounting for 63% of penile, 91% of anal, and 72% of oropharyngeal cancers.3 Male vaccination for HPV was approved in 2009 and currently is indicated for males 11-26 years of age for prevention of genital warts and the transmission of HPV.

New recommendations now state that girls and boys who initiate the vaccine between the ages of 9-14 years only require two doses, making completion of the vaccine series easier.4 Unfortunately, despite the importance of male vaccination, rates remain low.

The strength of this study is that it represents a national sample and, therefore, is generalizable. Limitations include obtaining vaccination history by self report. In addition, there is some concern that a one-time test of the penis may represent carriage of the virus, not true infection. The study also did not comment on HIV co-infection, presumably because men with HIV were excluded from the survey.

Nevertheless, this study confirms some HPV infection risk factors, such as age of sexual debut, age, and marital status. The study did not find circumcision to be protective, as many other studies have, and did not find an association with smoking, which is commonly known to be associated with female genital HPV infection and oropharyngeal infection. In contrast to females with HPV, the peak prevalence in men appeared to occur at an older age.

There is no recommendation for screening men for HPV in clinical practice, as there is no treatment, and, like women, most men clear the virus on their own.1 Unless men develop genital warts, they are asymptomatic from HPV and can transmit the virus without knowing.

Certain populations of men may be more at risk for developing HPV-related cancers, such as men who are immunosuppressed (e.g., men with HIV) and men who receive anal sex, who are more likely to have anal HPV, which may lead to anal cancers.5 Some physicians screen men in these high-risk groups with anal pap smears.

Han et al found the national HPV vaccination coverage among U.S. adult men was 11% and that only 5.6% reported completing the vaccine series. Clearly, more needs to be done to encourage vaccination of boys and men. The current recommendations for HPV vaccination in males are5:

  • All boys at age 11 or 12 years (or as young as 9 years);
  • Older boys through age 21 years, if they did not receive a vaccination when they were younger;
  • Gay, bisexual, and other men who have sex with men through age 26 years, if they did not receive a vaccination when they were younger;
  • Men with HIV or weakened immune systems through age 26 years, if they did not receive a vaccination when they were younger.

We should be encouraging our patients to vaccinate both their sons and daughters against HPV infection. This study confirms that HPV is very common and an important health issue for both men and women.

REFERENCES

  1. Centers for Disease Control and Prevention. 2015 Sexually Transmitted Diseases Treatment Guidelines. Available at: http://bit.ly/2qU7HtU. Accessed May 23, 2017.
  2. Dunne EF, Unger ER, Sternberg M, et al. Prevalence of HPV infection among females in the United States. JAMA 2007;297:813-819.
  3. Juckett G, Hartman-Adams H. Human papillomavirus: Clinical manifestations and prevention. Am Fam Physician 2010;82:1209-1213.
  4. Meites E, Kempe A, Markowitz LE. Use of a 2-dose schedule for human papillomavirus vaccination — Updated Recommendations of the Advisory Committee on Immunization Practices. MMWR Morb Mortal Wkly Rep 2016;65:1405-1408.
  5. Centers for Disease Control and Prevention. HPV and Men – Fact Sheet. Available at: http://bit.ly/2hGpqkd. Accessed May 23, 2017.