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What does the literature say about post-COVID syndrome? Is there any research quantifying the rates of organ-specific dysfunction in individuals with COVID-19 after discharge from the hospital?

Comment by InpharmD Researcher

A large-scale, retrospective analysis of British patients who were hospitalized (and discharged) with COVID-19 found an increased risk of mortality, readmission, and multiorgan dysfunction compared with similar individuals in the general population. This incidence was higher in older patients (>70 years) and was not uniform across ethnic groups. More research needs to be conducted to fully understand the risk factors for post-COVID syndrome to guide treatment to at-risk populations.

The National Institute of Health COVID-19 treatment guidelines state that there have been an increasing number of reports of patients who experience persistent symptoms and/or organ dysfunction after acute COVID-19. Data about the incidence, natural history, and etiology of these symptoms are emerging, and more research is needed to better understand the pathophysiology and clinical course of post-acute COVID-19 sequelae in order to identify management strategies. [1]

Persistent symptoms seen in COVID-19 patients after treatment include fatigue, dyspnea, and neuropsychological symptoms, and are seen in 35% of outpatient patients and 87% of hospitalized patients. While these symptoms are commonly reported, there is no certain way to diagnose the underlying reason as changes in metabolism, hormonal balance, and inflammatory messengers directed against one's own body and changes in brain function could contribute to the suffering of patients, especially those with fatigue.

Currently, it is too early to diagnose post-COVID syndrome. Symptoms must last at least six months, and those cases have not yet been reported. While a "post-COVID syndrome" cannot be diagnosed, it is possible that critically ill COVID-19 patients will have long term physical, cognitive, and psychological consequences once treatment is complete.

In conclusion, there is sufficient evidence for the possible existence of a post-COVID syndrome. [2]


1. COVID-19 Treatment Guidelines Panel. Coronavirus Disease 2019 (COVID-19) Treatment Guidelines. National Institutes of
Health. Available at Accessed [April 29, 2021].

2. Lamprecht B. Gibt es ein Post-COVID-Syndrom? [Is there a post-COVID syndrome?]. Pneumologe (Berl). 2020 Oct 8:1-4. German. doi: 10.1007/s10405-020-00347-0. Epub ahead of print. PMID: 33052198; PMCID: PMC7543035.

Literature Review

A search of the published medical literature revealed 1 study investigating the researchable question:

What does the literature say about post-COVID syndrome? Is there any research quantifying the rates of organ-specific dysfunction in individuals with COVID-19 after discharge from the hospital?

Please see Table 1 for your response.


Post-covid syndrome in individuals admitted to hospital with covid-19: retrospective cohort study


Retrospective, multicenter, observational, database analysis



To quantify rates of organ-specific dysfunction in individuals with COVID-19 after discharge from hospital compared with a matched control group from the general population.

Study Groups

COVID-19 (n=47,780)

Matched control (n=47,780)

Inclusion Criteria

Patients hospitalized with an episode of COVID-19 from January 1 to August 31, 2020

Controls: had at least one hospitalization record between January 1, 2019 to September 30, 2020; had not died before January 1 2020

Exclusion Criteria

Patients not discharged alive by August 31, 2020; unknown birthdate or sex; no matched controls


This was a retrospective review of the General Practice Extraction Service Data for Pandemic Planning and Research (GDPPR) database in the United Kingdom. Patients were followed from their discharge due to COVID-19 (index date) to September 30, 2020. Patients from the general population who were not hospitalized for COVID-19 were used as controls, and controls were matched to COVID-19 patients based on their index date.

Patients were also matched based on body mass index, age, smoking status, and comorbidities.


January 1 to September 30, 2020

Outcome Measures

Mortality, hospital readmission, major events

Baseline Characteristics


COVID-19 (n=47,780)

Matched control (n=47,780)

Age, years
















54.9% 54.9%

Body mass index, kg/m2
















71.9% 71.9%



COVID-19 (n=47,780)

Matched control (n=47,780)


12.3% 1.7%

Readmission to hospital

29.4% 9.2%

Respiratory disease






Events after discharge


Major adverse cardiovascular event

Chronic kidney disease

Chronic liver disease











Rates of all outcomes after discharge were greater in individuals with COVID-19 aged 70 or more than in those aged less than 70, whereas rates of all outcomes other than diabetes were greater in the white ethnic group than in the non-white group.

Adverse Events


Study Author Conclusions

Individuals discharged from hospital after COVID-19 had increased rates of multiorgan dysfunction compared with the expected risk in the general population. The increase in risk was not confined to the elderly and was not uniform across ethnicities. The diagnosis, treatment, and prevention of post-covid syndrome requires integrated rather than organ or disease-specific approaches, and urgent research is needed to establish the risk factors.

InpharmD Researcher Critique

While this is a large-scale database study, it is limited by lack of complete information and details regarding hospital readmission. Diagnoses were made by ICD-10 codes alone, which leaves room for assumptions and confounding variables. Due to the limited events in the control group, subgroup analyses could not be accurately conducted beyond age and race. 

The threshold for hospital admission with COVID-19 may have been lower than the controls, which may impact the rates of new diagnoses. Patients could be living with undiagnosed hypertension or diabetes before admission due to COVID-19, which may increase future admission rates. 

Additionally, these results only apply to patients hospitalized with COVID-19, not patients with mild or asymptomatic disease. Multiorgan post-COVID manifestations have been identified in individuals not admitted to hospital, which is beyond the scope of this study.


Ayoubkhani D, Khunti K, Nafilyan V, et al. Post-covid syndrome in individuals admitted to hospital with covid-19: retrospective cohort study. BMJ. 2021;372:n693. Published 2021 Mar 31. doi:10.1136/bmj.n693

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