September 28, 2021

expert reaction to study looking at incidence and co-occurrence of long COVID symptoms following COVID-19 infection and also after influenza

A study published in PLOS Medicine looks at incidence, co-occurrence, and evolution of long-COVID features following COVID-19 infection and influenza infection.

This Roundup accompanied an SMC Briefing.

Prof Amitava Banerjee, Professor of Clinical Data Science and Honorary Consultant Cardiologist, University College London, said:

“In a large, well-conducted and thorough study of electronic health records in the US, including over 270 000 COVID survivors in an overall population of 81 million, the authors had three novel aims. First, they investigated the impact on age, sex and other factors on the development of nine features of long COVID (chest/throat pain; abnormal breathing; abdominal symptoms; fatigue/malaise; anxiety/depression; pain; headache; cognitive dysfunction; and myalgia. Second, they studied the distribution and overlap between features of long COVID. Third, they compared new onset of these features following COVID-19 and following influenza.

“First, although incidence of long-COVID features was higher in older individuals, those with more severe initial COVID-19 illness, and in women, they also occurred in children and young adults with relatively mild illness, and in more than half of non-hospitalised patients. This supports the large-scale rollout of health services and specific research funding calls for observational studies and trials in non-hospitalised patients. Research such as the LOCOMOTION and STIMULATE-ICP studies in the UK will help in both respects(https://www.nihr.ac.uk/news/196-million-awarded-to-new-research-studies-to-help-diagnose-and-treat-long-covid/28205).

“Second, over half of patients (57%) had at least one long-COVID feature recorded in the 6 months after infection and one third (37%) in the 90 to 180 days after diagnosis. Importantly, the analyses suggest that the risk of long COVID features occurring, or co-occurring, continues to increase 6 months after initial illness.

“Third, the nine features were all more common after COVID-19 than for influenza, which is yet another arrow in the quiver against bogus “this is just like flu” claims.

“The authors do acknowledge most of the limitations in their report. There are some limitations inherent in electronic health record studies, such as quality of coding, and the completeness and the representativeness of the data. There are other limitations specific to this study. For example, although the 9 selected post-COVID symptoms are probably the most common in previous reports, it is well known that there are several other common symptoms and up to 200 symptoms reported by long COVID sufferers. Therefore, if anything, the reported incidence of symptoms after COVID infection is likely to be an underestimate.”

‘Incidence, co-occurrence, and evolution of long-COVID features: A 6-month retrospective cohort study of 273,618 survivors of COVID-19’ by Maxime Taquet et al. was published in PLOS Medicine at 19:00 UK time on Tuesday 28 September.

DOI: https://doi.org/10.1371/journal.pmed.1003773

All our previous output on this subject can be seen at this weblink:

www.sciencemediacentre.org/tag/covid-19

Declared interests

Prof Amitava Banerjee: “I am chief investigator of the STIMULATE-ICP study looking at long COVID.” https://www.stimulate-icp.org/

None others received.