Reducing Hospitalisations and Costs through a Medical Ambulatory Care Service

Authors: Pincombe, A.¹, Schultz, T.J.², Hofmann, D.³ and Karnon, J.⁴

1. Flinders Health and Medical Institute, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia; School of Public Health, Faculty of Health Sciences, The University of Adelaide, Adelaide, South Australia, Australia
2. Flinders Health and Medical Institute, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia
3. Flinders Health and Medical Institute, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia; Noarlunga General Internal Medicine Unit, Division of Medicine, Cardiac & Critical Care, Flinders Medical Centre, Bedford Park, South Australia, Australia
4. Flinders Health and Medical Institute, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia

Summary:

Increasing demand for hospital services can lead to overcrowding and delays in treatment, poorer outcomes and a high cost-burden and therefore there is an urgent need for programmes to help reduce unnecessary ED presentations and hospital admissions. The medical ambulatory care service (MACS), which has been operating since 2016 in the Southern Adelaide Local Health Network, provides out of hospital patient care, including diagnostic and therapeutic interventions for patients that require urgent attention, but which can be safely administered in the ambulatory environment. MACS accepts patient referrals from three sources: General Practitioners, Emergency Departments, and from Hospital Wards.

In this study, researchers evaluated the impact of the MACS programme on emergency department (ED) presentations, hospital admissions, length-of-stay and health service costs from a health system perspective, using a single group interrupted time series methodology with a multiple baseline approach. The researchers compared the utilisation of health services by patients grouped by referral stream over a 36 month period in order to compare patients’ hospitalisations pre and post their first admission to the MACS clinic.

In the absence of a comparison group of patients, researchers considered two counterfactual scenarios: a continuation of the increasing trend in health utilization based on pre-period predictions or a stabilization of utilization rates around the pre-MACS level. The effect of MACS on hospital admissions for the ED-referred group were inconclusive, but reductions in the rates of ED presentations following the patient’s first admission at MACS for the GP-referred group and reductions in the number of admitted bed days for the ED and Ward-referred groups were evident. The number of ED presentations reduced by around 0.36 ED presentations per 100 patients per 30 days, while the number of bed days declined by 1.56 and 3.70 days, per 100 ED-referred and ward-referred patients respectively. Under the two different counterfactual scenarios, the predicted net savings for MACS across three patient groups were $78,685 and $547,639 per 100 patients over 18 months.

MACS was found to be cost-effective for GP and ward-referred groups, but the expected impact on health service utilisation for ED-referred patients is sensitive to assumptions. Expansion of the service for GP-referred patients is expected to reduce hospitalizations the most and generate the largest net cost savings and further investigations into the types of patients for the service might prove to be the most effective and cost-effective are planned. The study adds to the small but growing literature on the economic evaluation of hospital avoidance programs.