Abstract
Introduction
New Zealand’s healthcare system is a mixed public and private system. The majority of healthcare is publicly-funded and provided. However, there is a significant private sector that is a major provider of elective care. For those able to access it, the existence of the private sector provides choice and flexibility, though it has been criticised as reinforcing inequitable practices in healthcare access.
Private hospitals in New Zealand do not generally offer a full complement of acute and emergency medical services. Consequently, some aspects of patient care must be provided and funded by the public system; for example, an acute admission to a public hospital following private treatment. Public readmissions following private care thus provide an identifiable way to measure the potential transfer of costs that are occurring between the two sectors. Questions are also raised around efficient and equitable use of public healthcare resources if considerable sums are being used to complete the medical care for privately-funded patients. This study aimed to explore this aspect of the public-private healthcare interface and estimate the cost of readmissions involved.
Methods
Routinely collected public and private hospitalisation data were used to identify patients with a private hospital admission between 1 July 2014 to 30 June 2019. Patients who were admitted to a public hospital within 7 and 28 days of being discharged from a private hospital were identified. Patient demographic characteristics and primary diagnoses were described for readmissions. Estimated costs to the public healthcare system were calculated using an assigned measure of resource use. Poisson and linear regression models were used to evaluate the effect of demographic variables on readmission rate and estimated cost respectively.
Results
Within the study’s inclusion criteria, 3% of private inpatient events resulted in a subsequent readmission to a public hospital within 7 days, and 5% within 28 days. The most common principal diagnosis for a public readmission was for complications of procedures. After controlling for demographic factors, older patients had much higher rates of readmission, along with patients living in high socioeconomic deprivation areas, and Māori and Pacific patients. The estimated public costs for all readmissions were approximately $20 million per year for 7-day readmissions and $30 million per year for 28-day readmissions. Older patients also had higher readmission costs per index private event after controlling for demographic characteristics.
Conclusions
The results of this study provide insight into the complex relationship between the public and private healthcare sectors in New Zealand. It reveals substantial cost-shifting from the private to public healthcare sectors arising from readmissions. Although the total estimated cost of the readmissions was a small percentage of the overall public budget for healthcare, public readmissions following private treatment are an ongoing cost to the health system and have significant implications for health policy and funding. The potential impact of cost-shifting should be considered when evaluating the efficiency and equitability of New Zealand’s healthcare system. The current healthcare reforms present an opportunity to assess this public-private relationship and endeavour towards a balance between patient choice and health equity.