The Alfred Health post‐COVID‐19 service, Melbourne, 2020–2022: an observational cohort study

To the Editor: Holland and colleagues reported on the Alfred Health post‐COVID‐19 service experience with the health of patients who had previously been hospitalised, or managed in a hospital‐in‐the‐home setting, with COVID‐19.1 Participants responded to an invitation to register for follow‐up, and then completed a questionnaire. The study also included a separate group (13% of the cohort) who were not necessarily admitted to Alfred Health but lived in the Alfred Health catchment — and might have been managed as outpatients or inpatients in another service but were referred by their local doctors to a specialist clinic targeted for patients with symptoms after initial COVID‐19, and subsequently completed the questionnaire.

Sixty per cent of respondents had at least one persistent symptom at eight weeks. The study reported apparently high prevalences of other symptoms, such as post‐traumatic stress disorder in 23%.

These results are derived from their cohort and may not be generally applicable. The authors caution: “We could not distinguish between new symptoms and those attributable to other health conditions. Our study did not include a contemporary control group”.1 More importantly, there was no control group of patients hospitalised from non‐COVID‐19 viral illness (with sufficient severe illness to lead to almost 5% spending time in an intensive care unit), who were then concentrated by an invitation, and then sufficiently motivated to fill out a questionnaire. Plausibly in such a group, at eight weeks, 60% would report at least one persistent symptom. Interpretation of their results is also obscured by the patients referred from the community, who came from a bigger population of patients with COVID‐19 concentrated to include only those who sought or agreed to a referral to a specialist follow‐up clinic.

The authors wisely identified weaknesses and they should be applauded for their review of their experience. More definitive conclusions about higher rates of persisting ill health caused by COVID‐19 (in comparison to similarly severe infectious illness) might be achieved if they can follow this up — as they perhaps recognise — with a prospective analytic design in a cohort of patients presenting with similar severity of viral illness comparing those with and without COVID‐19 over the long term.