Fifteen percent of healthcare workers at a Swedish hospital who recovered from mild COVID-19 at least 8 months before report at least one moderate to severe symptom disrupting their work, home, or social life, according to a research letter published yesterday in JAMA.
A team led by scientists at Danderyd Hospital, part of the Karolinska Institute in Stockholm, conducted the study from April 2020 to January 2021. The research involved obtaining blood samples and administering questionnaires to healthcare workers participating in the ongoing COVID-19 Biomarker and Immunity (COMMUNITY) study.
Symptoms for at least 2 months in 26%
Of the 323 participants who were seropositive, or had antibodies against SARS-CoV-2, indicating previous infection, 26% reported at least one moderate to severe symptom persisting for at least 2 months, compared with 9% of 1,072 seronegative participants (risk ratio [RR], 2.9). Similarly, 15% of seropositive and 3% of seronegative participants said they had a lingering symptom for 8 months or more (RR, 4.4).
Among the seropositive participants, 8% said that their lingering symptoms caused moderate to marked disruptions of their work life, compared with 4% of the seronegative group (RR, 1.8).
Likewise, 15% of seropositive participants said their persistent symptoms disrupted their social life to a moderate to marked degree, compared with 6% of the seronegative group (RR, 2.5). And 12% of the seropositive group reported disruptions to their home life, versus 5% of the seronegative group (RR, 2.3).
In addition to reporting at least one symptom lasting 8 months or longer, 11% of seropositive participants indicated a moderate to marked disruption in any category of the Sheehan Disability Scale, compared with 2% of the seronegative group (RR, 4.5).
Lower long-term quality of life
The most common symptoms lasting for at least 2 months in the seropositive group included fatigue, loss of smell or taste, and shortness of breath.
“However, we do not see an increased prevalence of cognitive symptoms such as brain fatigue, memory and concentration problems or physical disorders such as muscle and joint pain, heart palpitations or long-term fever,” senior author Charlotte Thalin, MD, PhD, said in a Karolinska Institute news release.
Seropositive group members who said they had no or mild previous symptoms had a median age of 43 years, and 83% were women, while median age in the seronegative group was 47 years, and 86% were women.
Among seropositive participants, 22% reported having chronic underlying conditions, compared with 24% of the seronegative group.
“The results of this study showed that a considerable portion of low-risk individuals with mild COVID-19 reported a diversity of long-term symptoms, and that these symptoms disrupted work, social, and home life,” the authors wrote. “Further research is needed to understand the mechanisms underlying COVID-19–related long-term sequalae.”
Lead author Sebastian Havervall, MD, said in the release that the findings illustrate the serious long-term consequences of COVID-19 after even mild illness. “Despite the fact that the study participants had a mild COVID-19 infection, a relatively large proportion report long-term symptoms with an impact on quality of life,” he said.
“In light of this, we believe that young and healthy individuals, as well as other groups in society, should have great respect for the virus that seems to be able to significantly impair quality of life, even for a long time after the infection.”