The Diagnosis Procedure Combination based situation analysis of surgical intervention for pituitary tumor in Japan

Abstract

There have been a number of literatures about the relationship between hospital volume and health outcomes. The previous literatures have indicated that for certain procedures and interventions, particularly complex surgery, there is a real possibility of improving outcomes by increasing activity volumes. The neurosurgery will be such a case. In the current study, we have investigated the relationship between volume and outcome (length of stay and charged cost) for surgical procedure of pituitary tumor. We have used the Japanese case-mix data, so called DPC from April 1, 2011 to March 31, 2012. There were 12,767 total discharge cases of pituitary tumor from 816 DPC hospitals. Among them we have used 2,664 surgical cases from 383 DPC hospitals. Using this dataset we have investigated the degree of concentration and factors associated with choice of procedures. Among the 383 facilities, all surgical cases were hypopituitarism or hyperpituitarism. Difference in sex was not clear and the age category 50-59 years old was the largest group. The upper 45 facilities treated 50% of surgical cases. For volume-outcome relationship, there were tendencies that higher case volume facilities had shorter ALOS (p=0.062, one-way analysis of variance) and smaller costs (p=0.087). Our result suggest the existence of volume-outcome relationship for pituitary surgery and the necessity of concentration of cases for better cost effectiveness.