Hospital at home for elderly acute patients: a study protocol for a randomised controlled trial

Abstract

Introduction

The increasing elderly population has led to a growing demand for healthcare services. A hospital at home treatment model offers an alternative to standard hospital admission, with the potential to reduce readmission and healthcare consumption while improving patients’ quality of life. However, there is little evidence regarding hospital at home treatment in a Danish setting. This article describes the protocol for a randomised controlled trial (RCT) comparing standard hospital admission to hospital at home treatment. The main aim of the intervention is to reduce 30-day acute readmission after discharge and improve the quality of life of elderly acute patients.

Methods and analysis

A total of 849 elderly acute patients will be randomised in a 1:2 ratio to either the control or intervention group in the trial. The control group will receive standard hospital treatment in a hospital emergency department while the intervention group will receive treatment at home. The primary outcomes of the trial are the rate of 30-day acute readmission and quality of life, assessed using the European Quality of Life-5 Dimensions-5-Level instrument. Primary analyses are based on the intention-to-treat principle. Secondary outcomes are basic functional mobility, resource use in healthcare, primary and secondary healthcare cost, incremental cost-effectiveness ratio, and the mortality rate 3 months after discharge.

Ethics and dissemination

The RCT was approved by the Ethical Committee, Central Denmark Region (no. 1-10-72-67-20). Results will be presented at relevant national and international meetings and conferences and will be published in international peer-reviewed journals. Furthermore, we plan to communicate the results to relevant stakeholders in the Danish healthcare system.

Trial registration number

NCT05360914.

Correspondence to Anne Marie Ladehoff Thomsen; [email protected]

STRENGTHS AND LIMITATIONS OF THIS STUDY

• This randomised controlled trial addresses a critical issue in healthcare with optimising care for the growing elderly population.

• By comparing hospital at home (HaH) treatment to standard hospital admission, this trial offers insights that can directly impact healthcare practices and resource utilisation.

• Our primary and secondary outcomes, including the rate of 30-day acute readmission, health-related quality of life, functional mobility, resource use and mortality rate, provide a comprehensive assessment of the impact of the HaH intervention.

• Blinding participants to the allocation is not feasible due to the nature of the intervention where patients are randomly allocated to either HaH or emergency department admission and treated in two different locations.

Introduction

Worldwide, there is a trend towards population ageing.¹ The Danish population that is above 65 years of age is expected to increase from 16% today to 25% in 2042, which will result in a larger demand for healthcare services.^{2 3} A substantial proportion of the elderly population will need care and treatment for acute medical conditions which in the majority of cases will be provided by the general practitioners (GPs). If patients’ condition needs further acute care, the patient will be referred to the emergency department (ED) at the hospital. This will result in an increased workload within the EDs and generally a growing demand for healthcare services in Denmark. For elderly, frail citizens an emergency admission is a stressful event and often means a great risk of infection, delirium and loss of functional ability, which takes a long time to regain.^4–6

The group of elderly medical patients is a broad group that demands a coherent and cross-sectoral treatment and is often only hospitalised for a short period of time. A Danish report about effective municipal prevention concluded that the hospitalisation of patients with rather uncomplicated treatment could possibly have been prevented if the collaboration between different primary and secondary sectors had been further improved.⁷ However, changing the standard patient pathway is challenging and requires collaboration between different sectors.

An alternative model of care that internationally has been identified as a possible solution is the hospital at home (HaH) treatment model. Several developed countries such as Spain and Australia provide HaH treatment.^{4 8 9} HaH is coordinated, multidisciplinary care in the home of the patient and offers active treatment of a condition that otherwise would have demanded emergency admission at a hospital and can be performed over a shorter period of time.^10–13 Studies have shown that it may be better for acute elderly patients to be treated at home with reduced risk of delirium and potential reduced risk of readmission,^14–16 where patients who are treated in their own home are more satisfied with their continuity of care.¹⁷ However, most of these studies were either prospective studies or randomised controlled trials (RCTs) that were inadequately powered to observe differences in the intervention and control groups.^14–17

An ED, emergency medical service (EMS), GPs, three municipalities, as well as different researchers, have organised an HaH treatment model for elderly acute patients in a Danish context in Central Denmark Region.⁹ It is expected that the patients will be able to play a more active role in their own treatment with increased quality of life, and that use of resources in the healthcare system will be optimised by avoiding unnecessary hospitalisations that impair and prolong treatment.¹⁸

Study objective

This article describes the protocol for an RCT that compares an HaH treatment model to standard care during admission in a Danish ED. The aim is to investigate the HaH intervention effect on the primary outcomes (30 days acute readmission and health-related quality of life (HRQoL) using European Quality of Life-5 Dimensions-5-Level (EQ5D-5L), and the secondary outcomes (functional mobility, mortality rate and health economic consequences) in acute elderly patients.

Hypotheses

We hypothesised that the HaH treatment model will be associated with a reduction in 30 days acute readmission, improvement in HRQoL, functional mobility and reduced healthcare resource use.

Methods and analysis

Study design and setting

We will conduct an open-label, RCT with a 1:2 allocation ratio of standard hospital admission versus HaH treatment. Assessments will be performed at admission (baseline), at discharge and 3 months after discharge. The trial will be conducted in collaboration between GPs, three municipalities (Viborg, Skive and Silkeborg), EMS and the ED at Viborg Regional Hospital, Regional Hospital Central Jutland, in the period between 1 June 2022 and 31 July 2026. To test the newly developed treatment model, a pilot phase was performed in Viborg and Skive municipalities, where we included 44 patients in the intervention group and 8 patients in the control group.

A steering group and a task force have been established in which all organisational units that are part of the research project are represented and actively participating in the meetings and in relevant decision-making.⁹ Steering group meets 3–4 times a year and receives monthly written updates on the progress of inclusion. At each meeting with the steering group, the strategies for achieving adequate participant enrolment to reach target sample size will be discussed, and if further action is needed, the decision will be made. Furthermore, cases of discontinuing HaH intervention will be discussed and appropriate strategies will be addressed.

Moreover, a project team consisting of researchers and authors of this article has been established to initiate and lead the trial. Changes to the protocol will be discussed within the project team and must receive approval from the steering group.

The protocol was designed in accordance with the Standard Protocol Items: Recommendations for Interventional Trials statement (please see online supplemental materials 1).¹⁹ The protocol is the first version and is registered at http://www.clinicaltrials.gov/, on 3 May 2022 (NCT05360914).

Eligibility criteria

Patients with an acute medical condition that is based on a clinical evaluation between the referring physician and the ED physician are capable of being randomised to HaH or ED admission.

Inclusion criteria are:

• 65 years old and above.

• Diagnosed with a stable acute medical conditions, for example, cystitis, erysipelas, pneumonia.

• Living in own home or a nursing home.

• Residing in one of the three municipalities (Viborg, Skive or Silkeborg).

• Visited at home by the GP, out-of-hours medical service or an EMS physician.

• Speaks and understands Danish.

• Informed consent to participate in the study.

Exclusion criteria include:

• Not being able to give written consent.

• The capacity of the municipal acute team care is fully used.

Recruitment process and informed consent

Patients will be identified through an emergency call by their referring physician (GP, out-of-hours medical service or EMS physician). Then the referring physician and the ED physician will jointly (through a conference call during the hospital visitation) evaluate, whether the patient can be included in the study. The conference call is a medical assessment of the patient to ensure that patient meets the inclusion criteria.

The ED physician will plan the acute treatment on the basis of the dialogue with the referring physician. After the conference call, the municipality acute team is called by the ED physician. At the first visit of the municipality acute team nurse, the patient gets an oral and written information about the project and informed consent is obtained.

Randomisation and blinding

Randomisation will be stratified by gender, municipality (Viborg, Skive or Silkeborg) and diagnosis (cystitis, erysipelas, pneumonia or other stable acute medical conditions). The participating patients are randomised to the intervention group or the control group. The randomisation process will be performed by the hospital visitation at the ED using REDCap.²⁰ Due to the nature of the intervention, where patients are treated in two different locations, there will be no blinding of the participants to the allocation, where the patients are randomly allocated to either HaH or ED admission.

Intervention

If the patient is randomised to the intervention group, the municipalities’ acute teams will start the treatment.

The acute team is a group of experienced nurses specialised in providing acute care at home. They can, for example, measure a patient’s vital signs, take venous blood samples, ECG, bladder scan and administer intravenous medications at home. If needed, the acute team takes blood samples and transports them to the hospital’s laboratory for processing. The acute team is available around the clock and visits patients whenever required under the supervision of the ED physician the treatment at home. The number of visits by the acute team or homecare nurse will depend on the patient’s condition.

There is no remote monitoring included in HaH treatment model. Patients are only monitored by the acute team who measure vital signs at each visit. The acute team contacts the ED physician if needed to discuss the patient condition. During the treatment daily course, the acute team and the specialist in emergency medicine discuss the treatment either over the phone or virtually on an iPad, where the patient is also involved. If the specialist wants to see the patient for a clinical examination or send the patient for an X-ray, he/she informs the acute team that the patient must undergo a short check-up in the ED. Here, the specialist examines the patient him/herself and assesses, whether the patient can continue to be treated at home, or whether the patient must be admitted to the hospital due to deterioration of the condition. If the patient is randomised to the control group, the patient will be admitted and receive the standard hospital treatment within the ED.

If the patient has any chronic diseases at the time of admission, it will be taken care of by the GP, who is the gatekeeper in the Danish healthcare system and has a record of patient chronic condition and medications. In addition, the ED physician will have a dialogue with the GP about chronic medications, so they handle and track the chronic medications in the acute treatment plan.

In case of an emergency at any time during the day, the patient has the opportunity to call the acute team who is available around the clock and will come and check on the patient. Alternatively, the patient can call 112, which is Denmark’s emergency number for life-threatening emergencies, and the EMS will visit the patient.

If the patient is randomised to the control group, the patient will be admitted and receive the standard hospital treatment within the ED. If patient needs medical services after they are discharged from hospital treatment or the HaH treatment, they will contact their GP for receiving services or contact EMS in case of an emergency.

Outcome measures

Our primary outcome parameters are the rate of 30-day acute readmission after discharge and the HRQoL. The rate of 30-day acute readmission will be obtained from the Danish National Patient Registry.²¹ We will use EQ5D-5L to measure HRQoL at admission, discharge and 3 months after discharge. We will use the Danish EQ5D-5L value set to give weights to different health states obtained from the EQ5D-5L instrument.²²

The secondary outcomes measures are functional mobility, resource use in primary and secondary sectors, cost estimation, and mortality rate. The functional mobility will be investigated using the ‘Timed Up and Go’ (TUG) test at admission, discharge and 3 months after discharge. TUG is often used to measure functional mobility in elderly populations to assess mobility skills and functional movements used in everyday life.²³ Box 1 provides an overview of the outcome measures that will be investigated in the project.

Box 1

Outcome measures

Primary outcomes

• Rate of 30-day acute readmission after discharge.

• Health-related quality of life using European Quality of Life-5 Dimensions-5-Level.

Secondary outcomes

• Functional mobility.

  • Timed Up and Go test (in seconds).

• Resource use in healthcare from randomisation to 3 months after discharge.

  • Number of hospital admissions within 1 and 3 months after discharge.

  • Length of hospital stay in days.

  • Number of bed days for intervention group.

  • Number of services provided at home for intervention group.

  • Number of outpatient visits.

  • Number of contact to the primary care (general physician, physiotherapist, etc).

  • Use of prescription medication outside hospital in defined daily doses.

• Costs from randomisation to 3 months after discharge (in Euro).

  • Costs of hospital admission.

  • Costs of outpatient visits.

  • Costs of municipal services.

  • Costs of primary care use.

  • Cost of prescription medication outside hospital.

  • Total costs per patient.

  • Incremental cost-effectiveness ratio which represents economic value of the intervention compared with control.

• Mortality rate 3 months after discharge.

Sample size

The primary outcome of the project is the rate of 30-day acute readmission after discharge, which is the outcome parameter used for the power calculation for the project. Levine et al show that the proportion of 30-day acute readmission for patients who have been treated in their own home is 0.07, while for patients in the hospital, it is 0.13.⁴ In order to show a difference in the proportion of acute readmissions with a significance level of 5% and 80% power and a ratio of 1:2, there must be 283 patients in the control group and 566 patients in the intervention group. Therefore, a total of 849 patients living in Viborg, Skive and Silkeborg municipalities will be included in the study.

Data

Data will be partly obtained from the Danish National Registries. The unique civil personal registration number assigned to all Danish citizens is obtained from The Danish Civil Registration System. The number encodes gender and date of birth and will enable accurate individual-level linkage between relevant Danish health registries.²⁴ Data on resource use in primary healthcare will be derived from the Danish National Health Service Register (number of primary care visits and related activity-based tariffs).²⁵ Data on resource use of secondary healthcare will be extracted from the Danish National Patient Registry and will be valued using tariffs of the Diagnostic-Related Grouping for inpatient admissions and the Danish Ambulatory Grouping System for outpatient admissions²⁶ while data on medicine use will be taken from the Danish National Prescription Registry.²⁷ Mortality rate will be estimated using the Register of Causes of Death.²⁸

Providing healthcare at home is a new patient pathway in Denmark, and there is no information about resource use in home setting. Therefore, a microcosting approach will be used to estimate the resource use and relevant cost of providing services in the municipalities. Microcosting is a method that provides crucial and detailed cost data. An accurate estimation of the cost of services provided at home at the microlevel is required to perform accurate economic analysis.²⁹ We intend to collect microcosting data for the first 100 patients and validate the quality of data. Should the data quality meet our standard, we will stop the data collection via microcosting and proceed to develop a tariff for HaH treatment model. Furthermore, we aim to write an article about our experience with microcosting and share the findings of resource use and cost of HaH treatment model. Data on resource use in municipalities, EQ-5D and TUG will be entered into dedicated databases and saved on a secure drive under Central Denmark Region. Data from the Danish registries will be analysed on the closed servers at Statistics Denmark. All data will be pseudonymised for analyses and will be handled and stored in accordance with the Danish Data Protection Agency requirements.

Statistical analysis

Statistical analyses will be based on ‘intention-to-treat’ principles to examine the effects of HaH treatment on primary and secondary outcome measures. Descriptive statistic of demographic and socioeconomic variables will be estimated using means and range for continues variables and percentages for categorical variables.

The rate of 30-day acute readmission and mortality rate will be investigated using Cox regression model. To analyse the TUG data, we will use Wilcoxon signed rank test to detect mean differences in time (in seconds) with 95% CIs within groups between admission and discharge in addition to discharge and 3 months after discharge.

The health economics analysis applies a healthcare perspective incorporating all the costs from the primary and secondary sectors. We will estimate the incremental monetary net benefit using a range of hypothetical threshold values for decision-makers’ willingness to pay for a quality-adjusted life-years (QALYs) and present the incremental costs and incremental QALYs visually in a cost-effectiveness acceptability curve (CEAC) using the net benefit regression framework. CEAC is used to illustrate the probability of the HaH care being cost-effective for a range of threshold values for willingness to pay for a QALY.^30–32 QALY will be estimated based on the obtained HRQoL scores. QALYs will be estimated as the area under the health utility curve over time using linear interpolation between observations.

In case of missing data, multiple imputation will be conducted for handling missing values. Sensitivity analyses will be conducted with adjustment for baseline variables including civil status, residency place. The effects are considered statistically significant at the 5% level. Data analysis will be performed by using STATA V.18 on Statistic Denmark’s server.

Patient involvement

During the pilot phase, four in-depth semistructured interviews were conducted to explore patients’ and relative’s preferences with regard to treatment site. Findings from the interviews were discussed at task force and steering group meetings to adjust the treatment pathway.

Safety considerations

The municipality acute team providing the treatment at home is in close contact with the ED specialist at the hospital (everyday they do ward rounds and the ED specialist is available for calls 24/7), and in case of any acute clinical deterioration of the patient’s condition at home, the patient will be transferred and admitted to the hospital immediately.

To ensure safety, audits are carried out continuously on all patients in the treatment pathway. Two ED physicians will independently evaluate each patient in the intervention group and assess, if the process of providing treatment is acceptable, or if there have been any delay or deficiencies in the treatment provided. The auditing findings will be continuously discussed with the participating ED physicians, the municipality acute teams, as well within the task force and the steering group. Moreover, in case of concerns of a patient’s condition, the treatment pathway for the patient will be discussed within a group consisting of the GP, the ED physician, the acute team at the municipality, the patient and patient’s relatives.

Time plan

Recruitment of patients to the RCT started on 1 June 2022 and randomisation will be terminated on 31 July 2026.

Ethics and dissemination

This study was approved by the Ethical Committee, Central Denmark Region (no. 1-10-72-67-20). Every eligible participant will be informed about the trial aims and procedures by a professional caregiver prior to informed consent, verbally and in writing. Confidentiality, voluntariness and freedom to withdraw from the study at any point will be stated.

We aim to present the results of the study at relevant national and international meetings and conferences, for example, emergency medicine congress’ and the world HaH congress. Findings from the research project will be communicated through a report, a conference and scientific publications in international peer-reviewed journals.

Discussion

Reducing hospital admissions among elderly patients and providing treatment closer to the patients’ homes is a crucial goal that several stakeholders in the Danish healthcare system have for achieving a ‘closer and cohesive healthcare system’.³³

Based on the Medical Research Council guidance, HaH intervention has all the features of a complex intervention.¹⁰ Intervention development in this study followed criteria of action research, where all the stakeholders were involved in designing the organisation of HaH treatment model through an iterative process.⁹ After designing the organisation of HaH treatment model using action research methods, we conducted a pilot study to ensure that the HaH treatment model would be suitable for elderly acute medical conditions in a cross-sectional setting and to define a suitable patient group for the RCT study. The pilot phase contributed in identifying practical barriers and facilitators to conduct the RCT.

We carefully considered, which outcome measures that would be used in the RCT. Most of the selected outcomes such as the primary outcome 30-day acute readmission and the secondary outcome mortality rate, will be obtained from the Danish registries that neither places a burden on participants nor depend on their ability to respond to questions from researchers. In the pilot phase of the study, we tested, whether the data collection for HRQoL as well as functional mobility (TUG test) were suitable for the participants, who may have cognitive impairments and could not be able to provide information. We found that the majority of the patients were able to respond to the EQ-5D and perform the TUG test, therefore, we will continue to collect this data during the RCT.

Given the fact that patients receive treatment in two different locations, we are unable to blind caregivers, participants and data collectors to the intervention with potential risk of detection and performance bias.³⁴ However, the primary outcome 30-day acute readmission rate and the secondary outcome mortality rate are unlikely to be affected by patients, caregivers and data collectors’ knowledge about the intervention.

This RCT study is one of the first to investigate HaH treatment model for elderly patients in a Danish setting and given the complexity of this intervention, it is recommended to be implemented and tested in local circumstances before being standardised and upscaled.¹⁰

The authors would like to thank the members of the task force and the steering group for their involvement, continuous support, and valuable input into designing the HaH treatment model. We also thank all the staff/personnel involved in the treatment model for their commitment to the project as well as contribution to data collection.

Ethics statements

Patient consent for publication

Consent obtained directly from patient(s).

Footnote

Contributors Each author has contributed significantly to the conception and trial design, formulating research questions and providing methodological expertise. ID is the project manager and played a pivotal role in collaborative efforts and ensuring the successful execution of the project. BO, CPN and HK provided overall guidance throughout the project. AMLT led the effect analysis and NT led the economic analysis aspect of the design. AMLT, ID and NT prepared the initial proposal for grant applications with input from BO, CPN and HK. AMLT and NT prepared the first draft of this study protocol. All authors had a key role in revising the manuscript and approved the final manuscript. AMLT and NT contributed equally to this manuscript and share joint first authorship.

Funding The project was funded by Health Foundation (HelseFonden, 20-B-0256), Novo Nordisk Foundation (NNF21OC0070180), Public Health Fund, Central Denmark Region (A4130) and The Quality and Training Committee, Central Denmark Region (1-30-72-29-19).

Competing interests None declared.

Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.

Provenance and peer review Not commissioned; externally peer reviewed.

Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.

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