Objective: To investigate epidemiological factors that predicts high-risk human papillomavirus (HR-HPV) types among women with atypical squamous cells of undetermined significance (ASCUS).
Methods: Case-control study of women with ASCUS and 'reflex' HR-HPV DNA test results at the Prentice Ambulatory Care (PAC) outpatient clinic, Northwestern University, Chicago, USA. Univariate analysis and logistic regression were done to generate measures of association between various epidemiological variables and positive HR-HPV.
Results: A total of 2,539 women had liquid-based Pap smear and 126 (4.96%) were confirmed ASCUS. Of the 126 with ASCUS, 125 (99.2%) had 'reflex' HR-HPV results. The prevalence of HR-HPV among women with ASCUS was 43.2%. Among the 54 with a positive HR-HPV, 76.0% were women <30 years and 24.0% were ≥ 30 years. The prevalence of HR-HPV was 61.2% among women <30 years versus 22.4% among women ≥ 30 years (P < 0.001). The mean age and standard deviations (SD) was 26.5 (6.2 years) and 34.6 (10.2 years) for women with a positive HR-HPV and negative HR-HPV test, respectively (P < 0.001). Age category <30 years was independently predictive of HR-HPV (adjusted odds ratio 4.6, 95% CI 2.0-10.7; P < 0.001).
Conclusion: Age <30 years significantly predicts presence of HR-HPV types among women with diagnosis of ASCUS. A strategy of limiting HPV testing to older women and referral of those <30 years for colposcopic assessment appears more effective.