Relationship between smoking, HPV infection, and risk of Cervical cancer

To document the relationship between smoking and HPV infection, and the risk of developing preinvasive lesions and cervical carcinoma.

Prospective, cross-sectional descriptive study. A total of 1,007 patients were recruited among women seen at the cervical pathology clinic of Sant Joan de Déu University Hospital in Barcelona (Spain) between January 2003 and March 2011. Patients were asked specifically about their smoking habits. Statistical analyses were done with SPSS v.19 software. Differences between groups were considered statistically significant at p < 0.05.

In patients studied, 48.7% were smokers. The average number of cigarettes per day among smoking patients was 7.07 (1-40). In the of patients with HPV infection, 53% were smokers versus 37% of patients without HPV infection (p < 0.05). The average number of cigarettes per day among patients with HPV infection was 7.64 cigarettes/day versus 5.55 cigarettes/day among patients without HPV infection (p < 0.05). In the patients with high-risk HPV genotypes infection, 54.5% were smokers versus 43.2% of patients without high-risk HPV infection (p < 0.05). Risk of HPV infection increases 1.905 times among smoking patients versus no smoking patients (OR = 1.905, CI 95% (1.426-2.545), p < 0.05). Among patients with changes associated to HPV and atypical cells, there were 29.2% and 14.4% of smokers, respectively, versus 45.5%, 55.6%, and 48.6% of smokers among patients with grade 1 cervical intraepithelial neoplasia (CIN 1), CIN 2-3, and carcinoma, respectively (p < 0.05). Risk of CIN 2-3 or cervical carcinoma cervical increases 1.642 times among smoking patients versus no smoking ones (OR = 1.642, CI 95% (1.325-1.884), p < 0.05).

Smoking interferes in the increase of HPV infection prevalence and in an increased risk of CIN and cervical carcinoma. Risk also increases with more cigars smoked per day.