Following acute infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), many patients have reported long-standing symptomatology even after a reasonable period of convalescence. This has been dubbed long COVID and has been noted to occur in as many as 80% of patients at up to four months from the onset of acute symptoms.
A recent study, released as a preprint on the medRxiv* server, examines the correlation of these symptoms with the patient’s socioeconomic status (SES) and perception of social discrimination, along with other social factors. The researchers found that the first two factors are associated strongly with long-term symptoms of COVID-19.
Earlier studies have shown that fatigue and headache are the most common symptoms in long COVID-19, occurring in almost 60% and 45% of cases, respectively. Others include inattention, alopecia and breathlessness, in about a quarter of cases each.
These COVID long-haulers are being studied in two multicenter initiatives called the Researching COVID to Enhance Recovery (RECOVER) study in the USA, and the Post-Hospitalisation COVID-19 (PHOSP-COVID) study in the UK, as well as independent research in smaller subsets of patients.
Neurological long COVID
COVID-19 often produces persistent neurological symptoms, probably because of the immune response to the infection, coupled with secondary features of the illness, and the use of invasive treatment modalities. Some ex vivo studies indicate the aberrant state of the organism in COVID-19, including high pro-inflammatory cytokine levels, disturbances in coagulation, endothelial dysfunction and hyperimmune responses skewed towards non-protective self-harming T cell activation.
COVID-19 is well-known to have hit racial and ethnic minorities harder than others, but the contribution of delayed or limited healthcare access and poor SES has not been codified so far. Some studies have shown that when these factors are accounted for, the disproportionate involvement of these groups is no longer obvious.
The current study, available on the preprint medRxiv server, examines this area, especially how the individual feels – a subjective criterion – as opposed to objective measures of social and economic status. This is because perceptions of being discriminated against or economically insecure lead to stress that may prolong or intensify the physical and neurological symptoms of long COVID.
Mechanisms of discrimination-induced symptoms
Discrimination based on appearance, disability, sexual orientation, race or religion often cuts a person off from medical care, making it more likely that the illness will persist or that complications may set in. The consequences of such discriminatory experiences include less use of healthcare services, mistrust of such systems, and going in for treatment too late or not at all.
This situation is also productive of stress and, in turn, a chronic dysregulation of the organism. The heart, brain, blood vessels, endocrine regulation, and immune responses are all affected by this generalized state of stress, making the individual more vulnerable to disease and death.
Prevalence of long COVID
The study involved over 1,100 patients with long COVID, making up over 70% of participants. A fourth of them had cognitive problems, mostly short-term memory issues (70%), poor attention (60%) and learning difficulties (20%). A fifth reported persistent problems with mood, especially anxiety or feeling jittery, in about 60%, with one in five describing depressive symptoms and one in seven saying they were short-tempered or agitated.
About 40% had fatigue, approximately one in four reported taste disturbances and a fifth had smell abnormalities. Sleep was disturbed, breathlessness reported, confusion or dizziness, and changes in appetite, in 15-20%.
Early or late infection?
During the first wave, infections were more likely to be followed by severe illness, long-term symptoms, more anxiety and lower quality of life compared to those infected in the second wave.
The results show that both the frequency of discrimination and the stress associated with the events act on each other to modulate the severity and persistence of illness. The higher the frequency, and the greater the intensity of discrimination, the stronger the odds of severe and lasting illness, if the individual experienced stress due to such discrimination.
The stress of discrimination was observed to be specifically associated with these adverse outcomes rather than stress in general.
Again, when the individual did not feel that the care being given was optimal, the perception of discrimination was higher, mediating more severe illness. The scientists also observed that neurological symptoms tended to last longer when the person experienced discrimination, correlated with the frequency of such events, and when COVID-19 was perceived to have disrupted life significantly.
Long-term cognitive symptoms and anxiety were not predicted by discrimination frequency, but were more likely with perceived SES or life disruption by COVID-19. Mood symptoms were also found to show a trend in this direction.
What are the implications?
The report shows that long-haul symptoms are very common following acute COVID-19 and that both perceived discrimination and perceived SES play a large role in predisposing individuals to high health risks. The most likely system to be affected is the neurological pathway, as shown by the predominance of neurological, mood and cognitive symptoms.
The researchers also noted that those who contracted COVID-19 early in the course of the pandemic were at higher risk for prolonged symptoms relative to those who got it later on. Chronic discrimination appears to be predictive of such long-term symptoms, mediated by discrimination-specific stress.
It appears that frequent experiences of general discrimination place individuals at greater risk for becoming more ill when infected, and at greater risk for experiencing increased lasting health complaints after recovery,” the scientists conclude.
The study brings out the reality and relevance of subjective experiences of discrimination as well, since the individual’s perception of SES affected recovery more than the actual SES, both being valid determinants. Secondly, patients who perceived that they were getting quality medical care tended to modulate the experience of discrimination, providing an approach to enhance recovery in such high-risk individuals.
More research in this domain appears to be a priority, since, if perceptions drive health outcomes, knowing which perceptions have predictive importance and how they affect specific outcomes would help shape policies to support and manage those at high risk of adverse sequelae.
medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.