Objective To analyze inpatient mortality cases in a tertiary general hospital in Beijing based on diagnosis-related groups (DRG), with the aim of providing references for healthcare quality management.

Methods We retrospectively collected DRG data of hospitalized patients admitted to a tertiary general hospital in Beijing from January 1, 2015, to December 31, 2023. Mortality cases were analyzed according to mortality risk stratification, with a focus on the temporal trends, departmental distribution, and DRG composition of low/medium-low mortality risk cases.

Results Among 927 304 DRG-classified hospitalizations, 2346 cases resulted in death (stratified into 130 low-risk, 209 medium-low-risk, 411 medium-high-risk, and 1596 high-risk cases), yielding an overall mortality rate of 0.25%. The mortality rates were 0.02% (130/680 939) in the low-risk group and 0.16% (209/130 449) in the medium-low-risk group. From 2015 to 2023, the mortality rate showed a significant downward trend (χ²=104.77, P < 0.001). Low/medium-low-risk mortality cases predominantly originated from the Medical Intensive Care Unit (MICU) and ICU (37.8%, 128/339). The most frequent DRG group among all mortality cases was RW29, while EC13 (Tuberculosis, Operating Room Procedure with Complications/Comorbidities) accounted for the majority of low/medium-low-risk deaths. The top three primary diagnoses were C34.101 (Malignant neoplasm of upper lobe of lung), J18.903 (Severe pneumonia), and J15.600x005 (Acinetobacter baumannii pneumonia).

Conclusions Critical care units accounted for the highest proportion of mortality cases, with surgical patients having complications/comorbidities representing the major DRG-related factors for low/medium-low-risk deaths. Hospitals should prioritize these findings by identifying areas for improvement, implementing multidisciplinary case reviews, and strengthening patient safety measures.