Combined antioxidant carotenoids and the risk of persistent human papillomavirus infection.

Persistent infection with human papillomavirus (HPV) is the primary etiologic factor for cervical cancer. The synergistic effect of carotenoids on HPV persistence has not been examined. To explore these potential synergies, we developed 2 measures of carotenoid status using circulating and dietary intake nutrients in which each nutrient was given equal weighting. We then compared persistent HPV infection with its counterpart, intermittent infection. In the analysis using the Crude Index, no association was observed between circulating nutrients and persistent infection with oncogenic HPV [odds ratio (OR)(adjusted) = 0.8, 95% confidence interval (CI) = 0.3-2.2)] or any type HPV (OR(adjusted) = 0.8, 95% CI = 0.3-2.1). Similar results were obtained using the Cumulative Index. However, associations between dietary intake and persistent infection were observed using both indexes. When the analysis was restricted to oncogenic HPV, a 50% higher risk was observed for women with low dietary carotenoid status using the Crude Index (OR(adjusted) = 1.5, 95% CI = 0.6-3.7). In the analysis using any type HPV, the adjusted OR for women with low dietary intake of combined carotenoids using the Cumulative Index was 2.4 (95% CI = 1.1-5.2). These results may be consistent with the hypothesis that low levels of carotenoids may increase the risk of persistent HPV infection.