There are different reasons for day clinic and full inpatient hospital stays. In 2019, the most frequent cause of inpatient stays (stays of at least one night) in acute hospitals were diseases of the circulatory system. They were the primary discharge diagnosis in 13% of all hospital stays, followed by injuries and poisoning (12% of stays), diseases of the musculoskeletal system or the digestive system and cancer (about 10% of stays each).
Most of the diseases treated by inpatient day care were eye diseases, almost 37% of all discharge diagnoses can be attributed to this group of diseases. In about 11% of cases, a malignant neoplasm caused an inpatient "zero-day stay"; compared to 2016, this corresponds to a decrease of about 73% (from 165 734 to 44 463 admissions). This is primarily due to the fact that chemotherapies and radiotherapy are nowadays more frequently performed as an outpatient procedure.