The Keio Journal of Medicine

Original Article
Multivariate Analysis of Factors Influencing Length of Hospitalization and Medical Costs of Cholecystectomy for Acute Cholecystitis in Japan: A National Database Analysis
Atsuhiko Murata, Kohji Okamoto, Shinya Matsuda, Kazuaki Kuwabara, Yukako Ichimiya, Yasufumi Matsuda, Tatsuhiko Kubo and Yoshihisa Fujino

Little information is available on the factors influencing length of stay (LOS) in hospital and medical costs during hospitalization associated with cholecystectomy for acute cholecystitis. We determined the independent factors affecting LOS and medical costs of patients who underwent cholecystectomy for acute cholecystitis based on data from the Diagnosis Procedure Combination (DPC) database. In 2008, a total of 2176 patients with acute cholecystitis were referred for cholecystectomy to 624 hospitals in Japan. We collected patient characteristics and data on treatments for acute cholecystitis using the DPC database and identified independent factors affecting LOS and medical costs during hospitalization using multiple linear regression models. Analysis revealed that early cholecystectomy was significantly associated with a decrease in LOS, whereas longer preoperative antimicrobial therapy was significantly associated with an increase of LOS: the standardized coefficient for early cholecystectomy was |0.372 and that for preoperative antimicrobial therapy was 0.353 (P < 0.001). These procedures were also significant independent factors with regard to medical costs during hospitalization: the standardized coefficient for early cholecystectomy was |0.391 and that for preoperative antimicrobial therapy was 0.335 (P < 0.001). Early cholecystectomy significantly reduces the LOS and medical costs of cholecystectomy for acute cholecystitis, while preoperative antimicrobial therapy increases LOS and medical costs during hospitalization. These results highlight the need for health care implementations such as promotion of early cholecystectomy, appropriate use of antimicrobial drugs, and centralization of patients with cholecystectomy for acute cholecystitis in Japan.