Study: Long COVID could involve factors other than SARS-CoV-2 infection
The authors said a range of factors–biological, psychological, or social–might trigger and maintain long COVID symptoms.
Researchers who compared rates of long COVID symptoms in young people with and without a history of mild SARS-CoV-2 infection found prevalence was equally high in the control group, suggesting contributions of other factors.
Researchers from Norway using a prospective cohort study design examined patients ages 12 to 25 from two counties who were enrolled between Dec 24, 2020 and May 18, 2021, a time when the Alpha variant was circulating. They included 404 people who tested positive for SARS-CoV-2 and 105 who tested negative. The team published its findings yesterday in JAMA Network Open.
The team evaluated the participants during the early convalescent stage and at 6-month follow-up. Study subjects underwent clinical exam, including pulmonary, cardiac, and blood tests to examine immunological and organ injury biomarkers. Researchers also conducted cognitive functional tests. They used the World Health Organization (WHO) definition for post COVID condition (PCC).
Prevalence of PCC 6 months after acute COVID infection was about 50%, but was equally high at 47% in the control group. The team didn’t find any biomarkers specific to viral infection at 6-month follow-up. The main risk factor for PCC was symptom severity at baseline. Two psychosocial factors stood out as risk factors for PCC: low physical activity and loneliness.
The researchers concluded that the findings question the usefulness of the WHO’s PCC case definition and suggest that factors labeled psychosocial should be considered as risk factors for persistent symptoms. “This does not imply that PCC is ‘all in the mind,’ or that the condition has a homogeneous, psychological etiology,” the authors wrote. “Rather, there might be heterogeneous biological, psychological, and social factors engaged in triggering and maintaining the symptoms of the individual.”
