INCIDENCE OF CERVICAL SMEARS INDICATING DYSPLASIA AMONG AUSTRIAN WOMEN DURING THE 1980S

Objective To determine the incidence of cervical smears indicating cervical intraepithelial neoplasia during the 1980s and to compare two quinquennia. Design A retrospective epidemiologic analysis was performed, based on a large collection of 238261 cervical smears obtained from Austrian women screened between 1980 and 1989. After application of strict epidemiologic criteria to avoid bias of changes in socio-economic status and methodological changes in cytology, 12 604 women were eligible for further analysis. We calculated incidences and relative risks of cytologically indicated cervical intraepithelial neoplasia, comparing the time periods of 1980 to 1984 and 1985 to 1989 for different age cohorts. Results We found a statistically significant increase in the incidence of cervical cytology indicating cervical intraepithelial neoplasia in the second time period for patients between 21 and 40 years of age. Women older than 40 years showed a significant decrease of this incidence. Conclusions In Austrian women between the ages of 21 and 40 years an unidentified risk factor or a pattern of risk factors during the period prior to 1985 resulted in an increase of cervical intraepithelial neoplasia during the last years studied. This increasing incidence of cervical intraepithelial neoplasia indicates the importance of regular cytological screening. The significant decrease of the cervical intraepithelial neoplasia incidence in women older than 40 years provides an argument for increasing screening intervals in these women.