Today in The Lancet Regional Health – Europe, a group of multinational researchers conclude that most Scandinavians who have long-COVID symptoms at 2 years had severe infections.
The observational study, led by Tongji University in China, compared the prevalence of 15 physical symptoms, assessed using the 15-item Patient Health Questionnaire (PHQ-15) among 64,880 adults with or without a COVID-19 diagnosis from Denmark, Iceland, Norway, and Sweden from April 2020 to August 2022. Participants were from four cohorts in the COVIDMENT Consortium.
Infected participants had 37% higher symptom rate
During up to 27 months of follow-up, 22,382 of 64,880 participants (34.5%) tested positive for COVID-19, and less than 1% were hospitalized. Relative to uninfected adults, those with COVID-19 had a 37% higher rate of severe physical symptoms (PHQ-15 score, 15 or higher; adjusted prevalence ratio [PR]).
The 9.6% of COVID-19 survivors who were bedridden for at least 7 days had the highest prevalence of symptoms (PR, 2.25), while those never bedridden had similar rates to uninfected participants (PR, 0.92). A higher prevalence was also noted in those hospitalized for their infections 2 to 22 months after diagnosis.
The prevalence of symptoms was significantly elevated among COVID-19 survivors for 8 of the 15 measured symptoms, including shortness of breath (PR, 2.15), dizziness (1.58), rapid heartbeat (1.55), headache (1.38), chest pain (1.34), back pain (1.10), low energy/fatigue (1.08), and sleep problems (1.04).
Our results show the long-term health consequences of the pandemic and highlight the importance of monitoring physical symptoms for up to two years after diagnosis, especially in people who experienced severe COVID-19.
Most participants had been partially or fully vaccinated against COVID-19, and the findings were comparable in analyses limited to vaccinated people. Symptoms were more prevalent among participants without depression or anxiety, which the study authors said indicates that the link between severe COVID-19 and the risks of long-term physical symptoms may be independent of mental symptoms.
"Long COVID has grown into a major public health problem since a large proportion of the global population has been infected," co-first author Emily Joyce, a doctoral student at Karolinska Institutet, said in an institute news release. "Our results show the long-term health consequences of the pandemic and highlight the importance of monitoring physical symptoms for up to two years after diagnosis, especially in people who experienced severe COVID-19."