Comparison of diagnosis-related group based reimbursement and case-mix index within hospitalized patients before and after modified malnutrition diagnosis.

Background and objectives: Lack of professional and accurate diagnosis of malnutrition led to a reduction in Diagnosis Related Group (DRG) payment and a decrease in Case-Mix Index (CMI). The aim of this study was to explore the effects of adding a proper nutritional diagnosis and modifying complication groups on DRG payment and CMI.

Methods and study design: Retrospective analysis was performed on patients ad-mitted to the hospital from January to June 2022 who had received a nutritional assessment. Patients were diagnosed as well-nourished, mild malnutrition, moderate malnutrition or severe malnutrition according to patient-generated subjective global assessment (PG-SGA) scores within 24 hours of admission. CMI and DRG hospital internal control standards were recalculated and compared with the original values.

Results: A total of 254 patients were enrolled, including 40 patients with mild malnutrition, 74 patients with moderate malnutrition and 122 patients with severe malnutrition. Of all subjects, 111 changed complication groups. The median of the DRG hospital internal control standard (12006.09 vs. 13797.19, p=0.01) and the median of CMI (0.91 vs. 1.04, p=0.026) were significantly higher than those before the diagnostic change. In patients with inflammatory bowel disease (IBD), the CMI value, hospital control standard of DRG, and the classification of DRG were significantly different from those before diagnosis revision (p<0.001).

Conclusions: Fully identification and correct coding of malnutrition cases are conducive for hospitals to receive appropriate DRG compensation, and further contribute to the improvement of medical quality and the economic sustain-ability of hospitals.