Epidemiological characteristics of suspected adenomyosis in the Chinese physical examination population: a nested case-control study

ObjectivesWe aimed to explore the epidemiological characteristics of suspected adenomyosis within a physical examination population in China.DesignA retrospective, nested case-control study; we matched healthy people and those with potential adenomyosis on a 1:2 ratio by age.SettingA tertiary hospital health management centre.ParticipantsWe included 15–60 years old women who underwent at least one uterine examination from October 2017 to December 2020, excluding those who had undergone hysterectomy and menopause.Primary and secondary outcome measuresWe estimated the incidence and prevalence rate of suspected adenomyosis. Conditional logistic regression was used to estimate associations between serum biomarkers and potential adenomyosis. Areas under the receiver-operating characteristic curves (AUC) were used to determine the cut-off point of the cancer antigen 125 (CA125) level for suspected adenomyosis.ResultsA total of 30 629 women had uterus-related imaging examinations; 877 had suspected adenomyosis. The standardised incidence and prevalence of suspected adenomyosis was 1.32% and 2.35%, respectively, for all age groups. The conditional logistic regression analysis results showed that total bilirubin≥18.81 µmol/L (HR: 2.129; 95% CI 1.067 to 4.249; p