Process-related predictors of readmissions and mortality following hip fracture surgery: a population-based analysis

PURPOSE: Readmissions are common and complicate recovery after hip fracture. The objective of this study was to study readmission rates, factors associated with readmissions and effects of orthogeriatric liaison service in a setting where patients are discharged typically on the first postoperative day from the operating tertiary care hospital to lower-level health care units. METHODS: A regionally representative cohort of 763 surgically treated hip fracture patients aged ≥ 50 years was included in this retrospective study, based on hospital discharge records. Primary outcome was a 30-day readmission, while the secondary outcome was a composite outcome, defined as readmission or death with a follow-up of 1 year at maximum. RESULTS: The 30-day readmission rate was 8.3% and 1-year mortality was 22.1%. Short length of stay did not lead to poorer outcomes. Delay from admission to surgery of ≥ 4 days and discharge to primary health care wards were associated with an increased 30-day readmission rate. Age ≥ 90 years, delay to surgery, postoperative length of stay of ≥ 2 days and discharge on a Saturday were associated with higher risk for the composite outcome. Use of orthogeriatric liaison service at the operating hospital was associated with a lower risk of 30-day readmissions (11.8% vs. 6.2%, P = 0.012) whereas in longer follow-up readmissions seemed to cumulate similarly independent of orthogeriatric contribution. Patients living in the largest community in the area were discharged to a secondary care orthogeriatric ward and had a lower risk of 30-day readmissions than other patients (4.8% vs. 10.2%, P = 0.009). CONCLUSION: Use of orthogeriatric liaison service and later care at secondary care orthogeriatric ward seem to be beneficial for hip fracture patients in terms of reducing readmissions and mortality. Of the other care-related factors, short delay from admission to surgery and short total length of stay in the operating hospital was also associated with these outcomes, which, however, may relate to the effects of patient characteristics rather than the care process.