Direct hospital costs for patients with inflammatory bowel disease in a Canadian Tertiary Care University Hospital

Abstract

OBJECTIVE: We set out to determine the direct costs of hospitalizations of patients with Crohn’s disease and ulcerative colitis admitted to a university-affiliated tertiary care hospital and to contrast the costs of medical versus surgical inpatient care, Crohn’s disease versus ulcerative colitis, and to identify dominant components of inpatient costs. METHODS: We used a patient-specific case costing system at Saint Boniface General Hospital, Winnipeg, Manitoba, for fiscal years 1994 and 1995. We extracted all inpatients whose hospital discharge abstracts included ICD-9-CM codes 555 (Crohn’s disease) and 556 (ulcerative colitis) among the top eight discharge diagnoses, and performed a chart review on all cases to ensure that the hospitalization was for inflammatory bowel disease and the diagnoses were accurate. We analyzed cases based on their disease diagnosis, primary mode of therapy associated with the hospitalization (medical vs surgical), and their major diagnosis-related group (DRG). This study evaluated direct patient care costs only and costs are expressed in Canadian dollars. RESULTS: Of 362 hospital admissions, 325 were eligible and of these admissions 275 belonged to the digestive system DRGs. Seventy-one (37%) were admitted more than once during the 2 yr of the study, accounting for 202 (62%) of the total number of admissions. The mean cost per admission of all cases of Crohn’s disease was $3,149 (95% confidence interval [CI], $2,665–$3,634) and for ulcerative colitis was $3,726 (95% CI $3,008–$4,445). Surgical therapy cases accounted for 49.8% of all admissions, 57.8% of all hospital days, and 60.5% of all costs. Patients treated surgically had more costly hospitalizations than those treated medically, particularly when analyzing only nontotal parenteral nutrition (TPN) cases. Surgical treatment admissions were significantly more costly for ulcerative colitis digestive DRG admissions than Crohn’s disease. The nondigestive DRG admissions were more costly than the digestive DRGs in all categories although this was only statistically different among medically treated Crohn’s disease. Patients treated medically were similarly costly whether they had Crohn’s disease or ulcerative colitis. There was no significant difference in cost per admission among cases admitted multiple times, compared with those admitted only once. TPN cases accounted for 9.5% of cases but 27.1% of costs. TPN-associated hospitalizations were more costly than non-TPN–use hospitalizations but these costs were primarily driven by duration of stay rather than TPN use itself. For all cases, the top five cost categories in descending order were nursing unit bed-days, drugs and pharmacy, diagnostic lab tests, operating room, and diagnostic imaging and endoscopy. CONCLUSIONS: Using our system we could determine direct costs for inpatients with inflammatory bowel disease and the factors that determined increased costs. Medical therapy admissions were similarly costly between Crohn’s disease and ulcerative colitis; however, surgical therapy admissions were costlier among ulcerative colitis patients. Admissions for nondigestive DRGs were more costly than those for digestive DRGs. TPN use identified a sicker group of patients who remained in the hospital longer than nonusers and, not surprisingly, these were the costliest patients.