UK study uses MRI scans to uncover organ impairment in long COVID

Many people with long COVID experience disabling symptoms. A source of frustration for patients and their doctors is that many routine blood tests and other assessments can be within the normal range despite the obvious suffering of patients. This hampers the ability of doctors to discover the drivers of long COVID.

Researchers at universities in the UK are conducting a study based on assessments, including MRI (magnetic resonance imaging) scans of key organs, of about 200 people who have long COVID.

Initial analysis of the data collected so far has found that many people with long COVID have ongoing health issues and reduced quality of life. What was novel about this study was its use of MRI scans. These scans helped researchers uncover that 70% of participants had at least one organ impaired in the months after they had been diagnosed with acute COVID-19. Key affected organs included the following:

  • liver
  • heart
  • lungs
  • kidneys
  • spleen

This study advances the field of long COVID research and shows that there is something happening deep within the body’s organs. Now other researchers need to confirm these findings of organ impairment. Also, researchers need to find out why different people with long COVID have different organs that have been impaired and what can be done about this.

Study details

There were 201 people who had acute COVID-19 in the past and who entered the present study nearly four months after their initial diagnosis.

The average profile of participants upon study entry was as follows:

  • age – 41 years
  • 71% women, 29% men
  • major ethno-racial groups: white – 88%; South Asian – 4%; Black – 2%
  • body mass index (BMI) – 26 kg/m2
  • 19% had been hospitalized with acute COVID-19

Among healthy people who had never been hospitalized for COVID-19, their average age was 39; 60% were men and 40% were women. This group’s average BMI was 23.


The most commonly reported symptoms of long COVID (whether or not people had been hospitalized) were as follows:

  • fatigue – 98%
  • shortness of breath – 88%
  • muscle ache – 87%
  • headache – 83%

According to the researchers, “99% of people [with long COVID] had four or more [symptoms] and 42% had 10 or more symptoms.”

MRI findings

Organ impairment was more common in people with long COVID than in healthy people. According to the researchers, 70% of people with long COVID “had impairments in at least one organ and 24% had multi-organ impairment, with overlap across multiple organs.”

Below are some of the findings from the MRI scans indicating the proportion of people with impairment of each organ and the type of impairment described by the researchers:

  • pancreas – 40%; inflammation, excess fat
  • liver – 28%; inflammation, excess fat
  • heart – 26%; inflammation, weakened pumping action
  • lungs – 11%; reduced ability to inhale/exhale
  • kidneys – 4%; inflammation
  • spleen – 4%; inflammation

Severe long COVID

Researchers found that people with severe symptoms of long COVID were more likely to report the following symptoms:

  • shortness of breath
  • headache
  • chest pain
  • abdominal pain
  • wheezing

People with severe long COVID were two times more likely to have heart inflammation than people who had moderate symptoms of long COVID.


As with several other research teams, the British researchers involved in the present study think that long COVID may be a syndrome with different manifestations in different people.

Bear in mind

The present study was imperfect; it could not prove that specific organ impairment resulted in specific symptoms. However, the study is an important step forward and has uncovered ongoing organ impairment in many people with long COVID. Why such impairment occurs and differs from one person to another is not clear.

Additional research is needed to find out more about the underlying biological issues that drive the symptoms associated with long COVID.

—Sean R. Hosein


Dennis A, Wamil M, Alberts J, et al. Multiorgan impairment in low-risk individuals with post-COVID-19 syndrome: a prospective, community-based study. BMJ Open. 2021 Mar 30;11(3):e048391.