The Long-Term Impacts of an Integrated Care Programme on Hospital Utilisation among Older Adults in the South of England: A Synthetic Control Study.

Introduction: Reducing hospital use is often viewed as a possible positive consequence of introducing integrated care (IC). We investigated the impact of an IC programme in North East Hampshire and Farnham (NEHF), in southern England, on hospital utilisation among older adults over a 55 months period.

Method: We used a Generalised Synthetic Control design to investigate the effect of implementing IC in NEHF between 2015 and 2020. For a range of hospital use outcomes, we estimated the trajectory that each would have followed in the absence of IC and compared it with the actual trajectory to estimate the potential impact of IC.

Results: Three years into the programme, emergency admission rates started reducing in NEHF relative to its synthetic control, particularly those resulting in overnight hospital stays. By year 5 of the study overall emergency admission rates were 9.8% lower (95% confidence interval: -17.2% to -0.6%). We found no sustained difference in rates of emergency department (ED) visits, and average length of hospital stay was significantly higher from year 2.

Conclusion: An IC programme in NEHF led to lower than estimated emergency admission rates; however, the interpretation of the impact of IC on admissions is complicated as lower rates did not appear until three years into the programme and the reliability of the synthetic control weakens over a long time horizon. There was no sustained change in ED visit rates.