Background
To identify the population level impact of a national pulse oximetry remote monitoring programme for COVID-19 (COVID Oximetry @home; CO@h) in England on mortality and health service use.
Methods
We conducted a retrospective cohort study using a stepped wedge pre- and post- implementation design, including all 106 Clinical Commissioning Groups (CCGs) in England implementing a local CO@h programme. All symptomatic people with a positive COVID-19 polymerase chain reaction test result from 1st October 2020 to 3rd May 2021, and who were aged ≥65 years or identified as clinically extremely vulnerable were included. Care home residents were excluded. A pre-intervention period before implementation of the CO@h programme in each CCG was compared to a post-intervention period after implementation. Five outcome measures within 28 days of a positive COVID-19 test: i) death from any cause; ii) any ED attendance; iii) any emergency hospital admission; iv) critical care admission; and v) total length of hospital stay.
Results
217,650 people were eligible and included in the analysis. Total enrolment onto the programme was low, with enrolment data received for only 5,527 (2.5%) of the eligible population. The period of implementation of the programme was not associated with mortality or length of hospital stay. The period of implementation was associated with increased health service utilisation with a 12% increase in the odds of ED attendance (95% CI: 6%-18%) and emergency hospital admission (95% CI: 5%-20%) and a 24% increase in the odds of critical care admission in those admitted (95% CI: 5%-47%). In a secondary analysis of CO@h sites with at least 10% or 20% of eligible people enrolled, there was no significant association with any outcome measure.
Conclusion
At a population level, there was no association with mortality before and after the implementation period of the CO@h programme, and small increases in health service utilisation were observed. However, lower than expected enrolment is likely to have diluted the effects of the programme at a population level.


What is already known on this topic
The COVID Oximetry @home (CO@h) programme was implemented in November 2020 to provide pulse oximeters to people with confirmed or suspected COVID-19 infection to support self-monitoring. A pilot of the programme was identified as being a safe pathway for patients but the effectiveness of the programme remains unknown.

What this study adds
Overall enrolment onto the programme in eligible people was low (2.5%). At a population level in England, there was no association with a change in mortality after implementation of the programme, and small increases in ED attendances and emergency hospital admissions.

How this study might affect research, practice or policy
Our findings suggest the CO@h programme is a safe pathway for patients with COVID-19, but due to low total enrolment at a population level, further research is needed to identify whether the programme is effective at an individual level.