The term long COVID, also known as post-COVID-19 condition, was coined in spring, 2020, by individuals with ongoing symptoms following COVID-19 in response to unsatisfactory recognition of this emerging syndrome by health-care practitioners. In September to November, 2020, clinical codes for persistent post-COVID-19 condition and related referrals were introduced and became available for use by health-care practitioners to record details of clinical encounters in electronic health records (EHRs) in England. EHRs, which cover a large proportion of individuals living in England, are increasingly used to help understand the epidemiology of disease alongside the effectiveness and safety of interventions. Many factors influence the completeness of information in EHRs, including help-seeking behaviour of patients and the discretion and data-recording behaviour of practitioners. Longitudinal population-based studies often include participant self-reports of illness; hence, these studies might be subject to reporting and participation biases. Comparing reported illness in studies to recorded illness in the EHRs of the same individuals might be helpful in understanding the epidemiology and clinical recognition of emerging conditions such as long COVID. We investigated whether individuals with self-reported long COVID between July, 2020, and October, 2021, had received a long COVID diagnosis or referral in the English health-care system after 20–32 months of follow-up (data cutoff: April, 2023), among 6405 participants of ten samples from longitudinal population-based studies that used COVID-19 survey data linked to EHRs in the UK Longitudinal Linkage Collaboration (LLC. Self-reported long COVID was defined as reporting 4 or more weeks of ongoing symptoms attributable to COVID-19, per National Institute for Health and Care Excellence 2021 guidelines. Seven of the ten samples from longitudinal population-based studies we used comprised reports of debilitating ongoing symptoms attributable to COVID-19, and the remaining three comprised reports of any ongoing COVID-19 symptoms, as described in our previous research and the. Long COVID-related health-care interactions were identified from International Classification of Diseases 10th edition and Systematized Nomenclature of Medicine Clinical Terms (known as SNOMED-CT) codes (listed in the from Hospital Episodes Statistics (the national database of English secondary care records) and General Practice Extraction Service Data for Pandemic Planning and Research (the national dataset of English COVID-19-relevant primary care records), respectively, for the period July, 2020, to April, 2023. Of 6405 participants with data on duration of COVID-19 symptoms and linkage to health records, 896 (14%) self-reported long COVID of any severity in longitudinal population-based study surveys. Among these 896 participants, just 48 (5·4%; 95% CI 4·1–7·0) were identified as having long COVID-related codes in EHRs, with codes assigned within a mean 5·4 months of symptom duration reporting. When restricting to individuals reporting a history of debilitating long COVID, this proportion was only marginally higher (6·3% [95% CI 4·3–9·2]; 25 of 395), with codes assigned within a mean 5·6 months of symptom duration reporting. In analyses of differences in coding by sociodemographic characteristics, likelihood of receiving a long COVID EHR code differed by age tertile, with the likelihood being highest among people of middle age (tertile 2; mean age 45·8 years) and lower in younger (tertile 1; mean age 25·2 years) and older (tertile 3;mean age 63·4 years) participants. Coding likelihood did not differ notably by sex or socioeconomic position. However, participants who reported they were of White ethnicity were more likely to receive a code than individuals of other ethnicities. LINK
The reasonable response would be to acknowledge that health records are a piss-poor source of data for this purpose, invalidating the studies that relied on this method, but as is tradition, it will instead be used to argue the opposite. Echoes of "we don't like to diagnose this" behind the 90% undiagnosed with ME. When of course the reality is that most people downplay and are in denial of symptoms in themselves as long as they can power through daily life, so it's actually an undercount that is hidden twice over by systemic failure to get serious with this problem. Missing 95% of anything is awful by any definition, but it's met with a shrug of indifference and more minimizing instead. So kind of missing from discussion, but this means about 6% reporting debilitating LC (395 out of 6405). This generally holds up rather well, but from memory early on this roughly 5-10% or so was more of the any type of Long Covid. 6% with debilitating looks about right from economic surveys, and that 14% with a wider but harder to notice effect. Numbers validated in many countries. Still the denial holds strong. Amazing. What a disaster the next pandemic will be, though. Literally all the wrong lessons learned. It's so bizarre to witness this.
