Therapeutic Impact of Initial Treatment for Chlamydia trachomatis Among Patients With Pelvic Inflammatory Disease: A Retrospective Cohort Study Using a National Inpatient Database in Japan

Abstract

Abstract Background Pelvic inflammatory disease (PID) is common among women of reproductive age and can be complicated by tuboovarian abscess (TOA), which is a serious and potentially life-threatening disease. However, recent mortality rates from PID on hospital admission and the short-term therapeutic usefulness of initial treatment for Chlamydia trachomatis remain unknown. Methods Using the Diagnosis Procedure Combination database, we identified patients who were diagnosed with PID on admission from July 2010 to March 2016 in Japan. We excluded patients who were pregnant, had cancer, or had missing data. Propensity score–adjusted analyses were performed to compare short-term outcomes between patients administered initial treatment for C. trachomatis and those without this treatment. The primary outcome was surgical intervention (laparotomy, laparoscopic surgery, and/or drainage procedure) during hospitalization. Results In total, 27841 eligible patients were identified. Of these patients, 2463 (8.8%) had TOA on admission. Mortality during hospitalization was 0.56% and 0.28% in the groups without and with TOA, respectively. Propensity score matching created 6149 pairs. A significant difference was observed in the primary outcome between those receiving initial treatment for C. trachomatis and the control group after propensity score matching (11.5% vs 13.4%; risk difference, −1.9%; 95% confidence interval, −3.1 to −0.7). The group that received initial treatment for C. trachomatis also had a significantly lower mortality rate. Conclusions In this retrospective nationwide study, initial treatment for C. trachomatis among hospitalized patients diagnosed with PID had clinical benefits in terms of improved short-term outcomes.