According to Dr. Jill Koshiol and colleagues, at least 70 percent of sexually active women will become infected with human papillomavirus (HPV) at some point in their lives.
HPV infection is temporary most of the time, but longer-term infection with high-risk strains of the virus is a key factor in the development of precancerous changes in the cervix and of cervical cancer.
Previous studies have already linked smoking with cervical cancer. To investigate whether cigarette smoking might affect the time it takes to clear an HPV infection, Koshiol and colleagues studied a group of 801 women from four large U.S. cities participating in a study of HIV. Out of the total, 522 of the women were HIV-positive.
After following for an average of about four years, researchers found that it took slightly longer for women who had ever smoked to clear HPV virus overall, and it took them significantly longer to clear higher risk strains of the virus.
"Smoking may increase a woman's likelihood of developing a persistent HPV infection by causing immunosuppression in the cervix," Koshiol and her colleagues write in the journal.
The study was limited by the fact that just 13.9 percent of all participants had never smoked, the team adds.
Researchers conclude that further research is needed to confirm that the relationship between smoking and HPV clearance varies with the virus strain.
