Temporal Trends in Genital Warts Among Individuals Covered by the Public Prescription Drug Insurance Plan in the Province of Quebec, Canada, From 1998 to 2007

Abstract

We assessed temporal trend in the incidence and prevalence of genital warts (GWs) in the province of Quebec, Canada, between 1998 and 2007 as a baseline for future assessment of the impact of Quebec human papillomavirus vaccination program. Data on GWs were obtained from the linkage of the physician service claims and the public insurance drug plan databases. Genital warts were identified through a prescription of podofilox, a medical procedure code specific to GWs or a diagnosis code for viral warts followed by a prescription of imiquimod or fluorouracil within 2 weeks. An episode was considered incident if it was preceded by a 12-month interval period free of GWs care. During the study period, a total of 27,138 episodes of GWs occurred among 24,267 individuals. The age-standardized incidence rate increased over time in men and women. The highest incidence was observed in women aged 20 to 24 years (391.9/100,000) and in men aged 25 to 29 years (383.3/100,000). Similar trends in prevalence were observed. The incidence and prevalence of GWs has increased among the population covered by the public insurance drug plan in Quebec.