Sometimes scientists are surprised by their own findings, even though they might have anticipated them in the first place.
This is the case with a new study from the Harvard T.H. Chan School of Public Health.
The researchers found that people with psychological distress before catching COVID-19 were significantly more likely to develop ‘long COVID’ afterwards than those who didn’t experience psychological distress.
And the symptoms were fairly broad
They included depression and anxiety – which have been linked with more severe cases of the flu, common cold and other infections – but also “worry about COVID-19, loneliness and perceived stress”.
The study of more than 3000 people also found that distressed people were “more likely to experience impairments in daily life a year after COVID-19 infection”.
‘Long COVID’ is defined as experiencing COVID-19-related symptoms, such as fatigue, brain fog, or respiratory, heart, neurological or digestive symptoms, for longer than four weeks after infection.
Strikingly, the increased risk identified in the study was independent of smoking, asthma and other health behaviours or physical health conditions.
“We were surprised by how strongly psychological distress before a COVID-19 infection was associated with an increased risk of long COVID,” said Dr Siwen Wang, a researcher in the Department of Nutrition at Harvard Chan School who led the study.
“Distress was more strongly associated with developing long COVID than physical health risk factors such as obesity, asthma and hypertension.”
The study
The study was launched in the very early days of the pandemic.
Even then it was recognised that some patients took longer to recover than others.
In April 2020 the study enrolled more than 54,000 people, who were asked about their psychological distress, then followed for a year.
Over the next 12 months, more than 3000 participants contracted COVID-19, and the researchers asked participants about their COVID-19 symptoms and symptom duration.
By then, ‘long COVID’ was more recognised as a syndrome.
After analysing the responses and comparing those who developed long COVID to those who did not, the researchers determined that distress before COVID-19 infection was associated with a 32 to 46 per cent increased risk of long COVID.
Psychological distress was also associated with 15 to 51 per cent greater risk of daily life impairment due to long COVID.
“To the best of our knowledge, this is the first prospective study to show that a wide range of social and psychological factors are risk factors for long COVID and daily life impairment due to long COVID,” said Dr Andrea Roberts, senior research scientist in Harvard’s Department of Environmental Health and senior author of the new paper.
“We need to consider psychological health in addition to physical health as risk factors of long COVID-19. These results also reinforce the need to increase public awareness of the importance of mental health and to get mental health care for people who need it, including increasing the supply of mental health clinicians and improving access to care.”
How this might complicate public perception
As we reported in May, there’s an idea that people who complain of suffering from ‘long COVID’ – the syndrome where debilitating symptoms of the disease persist for months – are actually struggling with psychological issues.
In February, The Guardian ran a piece – ‘The great gaslighting: how COVID long-haulers are still fighting for recognition‘ – that looked at the plight of New York patients who struggled to get doctors to take them seriously.
There has been persistent scepticism about ‘long COVID’, partly because researchers are playing catch-up with developing a precise diagnosis for this complex condition – which in turn would allow an accurate count of sufferers.
Exactly why psychological distress should increase the risk of long COVID remains unclear, the Harvard scientists say, and future research should look into any potential biological basis for the link.
However, they point to the fact that acute respiratory tract infections, such as influenza or common cold, mental health conditions “are associated with greater severity and longer duration of symptoms”.
More broadly, the new research is another indication that mental health and physical illness have a complex and often debilitating relationship.
