Long Covid linked with more than 200 symptoms, study suggests

Long Covid is associated with more than 200 symptoms ranging from fatigue and aching joints to brain and heart conditions, a major new study has found.

In the largest international study to date on the long-term impact of coronavirus, researchers led by a team at University College London spoke to thousands of people, with many sufferers reporting symptoms persisting for many months.

The most common symptoms were fatigue (experienced by 98 per cent of respondents), post-exertional malaise (the worsening of symptoms after physical or mental exertion, experienced by 89 per cent), and cognitive dysfunction, often called brain fog (experienced by 85 per cent).

Other symptoms included visual hallucinations, tremors, itchy skin, changes to the menstrual cycle, sexual dysfunction, heart palpitations, bladder control issues, shingles, memory loss, blurred vision, diarrhoea, and tinnitus.

The study, which is published in the Lancet’s EClinicalMedicine journal, involved 3,762 participants from 56 countries – 1,020 of whom were confirmed cases and 2,742 who were suspected of having the illness.

Researchers identified a total of 203 symptoms in 10 organ systems, with 66 symptoms tracked for seven months.

The team behind the report, who have all had or continue to have long Covid, are calling for clinical guidelines on assessing affected patients to be widened beyond cardiovascular and respiratory function tests, to take account of a wider range of symptoms including those affecting neuropsychiatric and neurological function.

Dr Athena Akrami, a neuroscientist at the Sainsbury Wellcome Centre at UCL and senior author of the report, said: “While there has been a lot of public discussion around long Covid, there are few systematic studies investigating this population; hence relatively little is known about its range of symptoms, and their progression over time, the severity, and expected clinical course (longevity), its impact on daily functioning, and expected return to baseline health.

“In this unique approach, we have gone directly to ‘long haulers’ around the world in order to establish a foundation of evidence for medical investigation, improvement of care, and advocacy for the long Covid population. This is the most comprehensive characterisation of long Covid symptoms, so far.”

The study found that the probability of symptoms lasting beyond 35 weeks (eight months) was 91.8 per cent.

Among all of the respondents, 3,608 (96 per cent) reported symptoms lasting beyond 90 days, while 2,454 (65 per cent) experienced symptoms for at least 180 days.

Among those who were experiencing symptoms for at least six months, the most common included fatigue (80 per cent), post-exertional malaise (73 per cent), cognitive dysfunction (58 per cent), sensorimotor symptoms (56 per cent), headaches (54 per cent), and memory issues (51 per cent).

During their illness, participants reported an average of 55.9 symptoms (out of the longer list of 203 measured in the study), across an average of 9.1 organ systems.

Around nine in 10 (89 per cent) of the participants said their symptoms returned, with exercise, physical or mental activity, and stress listed as the main triggers.

Nearly half (45 per cent) said they had to reduce the number of hours they worked as a result of the illness and more than one in five (22 per cent) were not working at all at the time of the survey.

Dr Akrami said: “For the first time this study shines a light on the vast spectrum of symptoms, particularly neurological, prevalent and persistent in patients with long Covid.

“Memory and cognitive dysfunction, experienced by over 85 per cent of respondents, were the most pervasive and persisting neurologic symptoms, equally common across all ages, and with substantial impact on work.

“Headaches, insomnia, vertigo, neuralgia, neuropsychiatric changes, tremors, sensitivity to noise and light, hallucinations (olfactory and other), tinnitus, and other sensorimotor symptoms were also all common, and may point to larger neurological issues involving both the central and peripheral nervous system.

“Along with the well-documented respiratory and cardiovascular symptoms, there is now a clear need to widen medical guidelines to assess a far wider range of symptoms when diagnosing long Covid.

“There are likely to be tens of thousands of long Covid patients suffering in silence, unsure that their symptoms are connected to Covid-19.”

The authors did however caution that the retrospective nature of the study increased the possibility of recall bias, while the fact the survey was distributed in online support groups raised the risk of a sampling bias toward long Covid patients who joined support groups and were active participants of the groups at the time the survey was published.

The survey was also predominantly answered by English-speaking (92 per cent) and white (85 per cent) respondents, raising the possibility that some conditions experienced by other demographics may not have been recorded.