A longitudinal study conducted during the pandemic has found evidence that people with greater psychological distress are not only more likely to get infected with COVID-19, but more likely to experience severe symptoms. The findings were published in the journal Annals of Behavioral Medicine.
A wealth of scientific findings have suggested an intricate link between mental and physical health. For example, previous viral challenge studies have exposed healthy volunteers to respiratory viruses and found that psychological stress is tied to the likelihood of catching a virus and also the severity of symptoms.
Study authors Kavita Vedhara and her colleagues recognized the COVID-19 pandemic as an opportunity to re-explore the link between psychological distress and susceptibility to illness. Given that the novel coronavirus appears to manifest itself differently in different people and to infect some and not others, the researchers proposed that psychological variables might explain some of this puzzling variability.
“I have always been interested in whether or not (and how) psychological factors influence health and, in particular, whether the effects on health are clinically relevant i.e., do they influence who gets a disease and/ or how we respond to disease,” said Vedhara, a professor of health psychology at the University of Nottingham
Throughout the coronavirus pandemic, the researchers collected three waves of data from UK residents. The data included assessments of depression, stress, anxiety, and positive mood. The surveys were completed in April 2020, during the first national lockdown, between July and September of 2020, alongside the easing of restrictions, and in November and December 2020, during the second national lockdown. A total of 1,087 participants responded during both the first and last waves.
At the third wave only, the respondents reported whether they had ever tested positive for COVID-19. They also reported whether they believed they had ever contracted COVID-19 regardless of whether they had taken a test. This second measure was included since limited testing capacity during some months of the pandemic meant that many respondents may not have had access to tests. Respondents additionally reported which COVID-19 symptoms they experienced and how severe their symptoms were.
The researchers conducted various regression analyses to explore whether reported psychological distress (lower positive mood and higher depression, anxiety, and stress) would predict reported COVID-19 infection and symptom severity. Importantly, they controlled for sociodemographic variables that might influence risk of infection, such as age, gender, COVID-19 risk category, and essential worker status.
The results revealed that participants who reported greater distress during April 2020 or during the summer of 2020 were more likely to report believing they had contracted COVID-19 when asked at wave 3. Moreover, they also reported a greater number of symptoms and reported symptoms that were more severe. The same pattern of findings held when the researchers used aggregated measures of psychological distress experienced in April and in the summer of 2020.
“We all know the effects of this pandemic on our emotional health have been brutal. But these findings show that, as has been observed many times before in the context of other viruses, that distress is not only a consequence of living with the risk of COVID-19, but may also be a risk factor for who gets it and how severe the disease is,” Vedhara told PsyPost.
When only analyzing participants who reported positive test results for COVID-19, findings trended in the same direction. However, the effect did not reach significance, possibly because the subgroup of respondents who tested positive for COVID-19 was small, at only 34 respondents.
The researchers theorize possible reasons why psychological distress might be associated with COVID-19 outcomes. On the one hand, it may be that psychological distress is impacting health behaviors, such as alcohol intake and sleep quality, which is in turn affecting vulnerability to infection. Alternatively, psychological distress may be triggering the release of cortisol, which could be suppressing the immune system and increasing the risk of contracting COVID-19. The authors note that this is only speculation, based on evidence suggesting elevated cortisol levels in people infected with COVID-19.
The findings were limited since the measure of COVID-19 infection was self-reported, and Vedhara and her colleagues mention “an urgent need to examine whether our results are replicated in cohorts where data on verified cases of infection are available.” They further suggest that, “future work focusing on laboratory assessment of antibodies to SARS-CoV-2 and/or verified test results would permit greater confidence in the associations described here.”
“We had to rely on self-reported COVID-19 infection in this study because at the time testing for the disease was not widely available,” Vedhara explained. “So the next step in this work would be to see if the relationships we have seen with self-reported infection are replicated when we look at verified infection.”
The study, “Psychological Predictors of Self-reported COVID-19 Outcomes: Results From a Prospective Cohort Study”, was authored by Kieran Ayling, Ru Jia, Carol Coupland, Trudie Chalder, Adam Massey, Elizabeth Broadbent, and Kavita Vedhara.